NC1007: Enteric Diseases of Swine and Cattle: Prevention, Control and Food Safety

(Multistate Research Project)

Status: Inactive/Terminating

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SAES-422 Reports

Annual/Termination Reports:

[10/01/2004] [02/09/2005] [10/10/2005] [12/27/2006]

Date of Annual Report: 10/01/2004

Report Information

Annual Meeting Dates: 11/08/2003 - 11/09/2003
Period the Report Covers: 10/01/2002 - 09/01/2003

Participants

Besser, Thomas E. - Washington
Duhamel, Gerald - Nebraska;
Francis, David H. - South Dakota;
Gebhart, Connie - Minnesota;
Isaacson, Richard _ Minnesota;
Joens, Lynn A.- Arizona;
Kaushik, Radhey S. - South Dakota;
Kuhlenschmidt, Mark - Illinois;
Maes, Roger - Michigan;
Moxley, Rodney A. - Nebraska;
Nietfeld, Jerome - Kansas;
Kaushik, Radhey S. - South Dakota;
Robertson, Donald C - Kansas;
Saif, Linda - Ohio;
Schultz, Bruce - Kansas;
Stromberg, Bert - Minnesota, Administrative Advisor;
Torrence, Mary - CSREES Representative;
Wyatt, Carol - Kansas;
Young, Alan - South Dakota;

Brief Summary of Minutes

Dr. Mark Kuhlenschmidt called the meeting to order at 8:50 am and new members and guests were introduced. Dr. Kuhlenschmidt then introduced Dr. Bert Stromberg as the new Administrative Advisor for NC1007. Dr. Stromberg presented his opening remarks, stressing that the North Central Regional Association emphasizes collaboration among members. This needs to be demonstrated by multi-institutional publications.
Dr. Mary Torrence presented the CREES report. She provided a recent CSREES Budget summary and announced currently available RFAs and deadlines for proposal submissions. She informed the group about new initiatives and new directives in NRI for this next year. There is a need to develop a consortium of top researchers to address these new initiatives and intervention and management strategies will be important issues as they will have more impact. She recommended that the NC1007 group organize a large, multi-state proposal. Dr. Stromberg suggested a food safety multi-state project, using the recent PRRS proposal that has an internal grant review process as an example. This would give the group the flexibility needed to move in different directions. He reminded the group that CSREES wants a minimum number of proposals with maximum expertise represented.
From 9:15 am on participants from the various experiment stations presented and discussed progress reports and principle accomplishments concerning their work on the NC-1007 project. In addition to the agenda were presentations by Dr. Besser on the epidemiology of antibiotic resistance and by Dr. Rahdy on establishment of a primary bovine fetal intestinal epithelial cell culture.
At 4:10 pm, after the presentation of progress reports, Dr. Torrence, CSREES representative, commented on the large pool of expertise and wide range of species of organisms represented by NC1007. She suggested potential collaborative proposals for submission for NRI or NIH funding. Also, she would like to see less time and energy focused on presentation of research and more discussion of collaborative projects. Ideas were presented and discussed for large collaborative research proposals, including a national clinical trial of E. coli intervention strategies, the affects of elimination of growth promotors on animal health and food safety, the interplay of viral plus bacterial pathogens in the intestine of animals on food safety and zoonosis/how pathogens cross species barriers. Dr. Torrence is willing to work with the NC1007 group to identify alternative sources of funding and/or matching funds. She suggested that the group put together a pre-proposal which she would present to funding agencies to assess the level of interest in the ideas presented. The meeting was adjourned at 5:00 pm.
The breakfast business meeting began at 8:05 am, November 9, 2003. We discussed the need for a new chair and co-chair for the CRWAD Enteric Disease Section and a keynote speaker for 2004. Dr. Stromberg volunteered to set up a ListServe for communication among NC1007 members.
The business meeting was officially called to order at 8:45 am by Dr. Kuhlenschmidt in the meeting room. Announcements were made. Two Enteric Disease session chairs will be needed next year. An Animal Health Symposium grant will be used to pay honoraria to keynote speakers. Dr. Joens provided an update on CRWAD Committee business. Dr. Saif announced that NRI is soliciting topics from NC groups and suggested we submit topics. We decided that excess dues would be deposited to a SDSU account for use for the Graduate Student Awards, that we needed to disseminate our NC1007 information in an outreach fashion, and that we needed to find a web administrator to set up and maintain a NC1007 web site. Further discussion was directed towards outreach possibilities and the topic of a Symposium on Food Safety and/or Zoonotic diseases in general was reintroduced. There was no further business and the business meeting was adjourned.
At 9:30 am new officers were elected. Both Drs. Maes and Besser were nominated to serve as Secretary. Dr. Besser declined nomination due to time constraints; Dr. Maes was unanimously voted new secretary.
Instead of individual state collaboration discussions, the group as a whole discussed some avenues for creative new collaboration at 9:45 am. We discussed the outreach objective from the grant and decided to investigate setting up an informative web page and/or a meeting targeted toward producers or veterinary groups, which would include enterics, food safety and maybe even bioterrorism topics.
More novel means of cooperative research that may result in collaborative grants were then discussed. Topics were discussed that would merge the groups expertise in and diversity of research. After discussion, group settled on the following general objectives:
1) What happens to the prevalence of zoonotic organisms in the presence/absence of growth promoters in animals?
2) What happens to the prevalence of animal pathogens in production animals grown in the presence and absence of growth promoters?
3) What happens to antimicrobial resistance profiles in zoonotic and animal pathogens in animals grown in the presence and absence of growth promoters?
4) What happens to therapeutic effect and disease rates with/without growth promoters, antibiotics, and on induced and native immunity?
Dr. Torrence will approach funding agencies with the listed objectives and if there is a positive response from the funding agencies, NC1007 members will reconvene early 2004 to have further discussions and add specifics to the proposal. Drs. Isaacson and Besser volunteered to co-chair the organization of this interdisciplinary project.
Dr. Saif announced that all station reports will need to be on CDs for preparation for the next project rewrite.
The meeting was adjourned at approximately 12:00pm.

Minutes Attachment:

Attachment

Accomplishments

Objective 1: Define mechanisms of pathogen-host-environmental interactions in enteric and food borne diseases Brachyspira NE investigated a laboratory mouse model of B. pilosicoli-host interaction. An NADH oxidase gene (nox) PCR-based RFLP method has been developed for rapid identification of pathogenic and commensal Brachyspira present in a wide range of hosts. Three penicillin-binding proteins (PBPs) homologous to the PBPs 1, 3 and 5/6 of Escherichia coli have been identified in the membrane of B. pilosicoli. Campyobacter AZ assessed the pathogenicity of Camplobacter jejuni in broiler chickens. Broiler cecal samples were collected from processed biruds n processing plants located in Kansas, Iowa, and Washington. To date 315 samples have been collected and processed and 120 positive samples have been isolated. Az also assessed the presence and potential virulence of C. jejuni isolated from food and companion animals. Bovine, canine, feline, and avian feces or intestinal swabs from carcasses were cultured for C. jejuni and identity confirmed using broth enrichment and selective plating and PCR. A total of 437 fecal swabs were evaluated and 13,8% of dogs, 5% of goats, 94.7% of cattle, and 1.7% of avian species were positive for C. jejuni. All positive isolates were found be of comparable pathogenicity to C. jejuni M129, a human clinical strain. None of the isolates were resistant to either erythromycin or gentamicin and only 2% were resistant to ciprofloxacin although 25.5% were resistant to tetracycline. Az reported the isolation of potentially novel virulence genes from C. jejuni by cell sorting of a GFP promoter library. Coronavirus KS has isolated coronavirus from a horse with diarrhea. The virus hemagglutinates mouse erythrocytes and cross reacts with bovine coronavirus in ELISA assays. Cryptosporidium IL has isolated and partially characterized the intestinal lipid component that inhibits sporozoite binding to host cells and is currently identifying sporozoite genes transcribed in response to exposure to this lipid and binding to host cell membrane vesicles. Escherichia coli NE demonstrated EAST1 expression by a porcine strain of enterotoxigenic E. coli (ETEC). Genes for EAST1, LT and STb were located on large plasmids; genes for the latter two enterotoxins occurred on the same plasmid, whereas those for EAST1 occurred on a separate plasmid. Specific anti-capsular antibodies mediated bactericidal activity of porcine serum against a serum resistant ETEC strain, and killing activity occurred via the alternative complement pathway. Vaccination alone or in combination with direct-fed microbial product significantly reduced the prevalence of E. coli O157:H7 in feedlot cattle in clinical trials. SD demonstrated that E. coli expressing K88 fimbriae targeting glycoprotein receptors display greater virulence than those strains with K88 fimbriae targeting glycolipid receptors. Fimbriae alone cannot account for successful colonization of piglet intestines by E. coli and virulence of O157:H7 E. coli strains is highly correlated with the amount of Shiga toxin 2 produced by the strain in vitro. Lawsonia intracellularis MN has followed the progression of gross and histologic lesions associated with Lawsonia intracellularis(LI) infection in pigs and has evaluated the production of mucosal secretory IgA specific against the bacteria. MN has completed sequencing and annotation of the genome of LI. Overall the LI genome is 1,719,350 bp in size with one chromosome and three plasmids encoding a total of 1,346 ORFs. Sequencing and annotation also revealed, among others, a very large (26 kb) unique protein composed almost entirely of a-helices, located on the large plasmid and comprises ~2% of the entire genome. The analyses also identified numerous genes involved in pathogenicity and toxin production, including a largely intact Type III secretion system and numerous flagellar genes. Newly Recognized Enteric Viruses and Caliciviruses MI determined that bovine noroviruses and toroviruses were very prevalent in diarrheic samples collected from Michigan and Wisconsin dairy farms. OH previously determined the effective factor in intestinal contents preparation (ICP) required for porcine enteric calicivirus (PEC) growth in cell culture is a protein (or peptide) of < 50 kDa and that replication of PEC may depend on a cAMP signaling pathway suggesting a novel pathway for replication of an intestinal virus. Capped RNA transcripts derived from a full-length cDNA of the tissue culture adapted (TC) Cowden PEC were infectious when transfected into LLC-PK cells but only in the presence of IC. The infectious clone had 4 amino acid point mutations throughout its genome compared to the parent TC-PEC. Futhermore, the infection of gnotobiotic pigs with TC or wild type PEC induced similar serum neutralizing and serum or intestinal IgM, IgA and IgG antibody responses and protection against diarrhea. Rotavirus IL has synthesized a neoglycolipid receptor mimetic and demonstrated its ability to protect newborn pigs from rotavirus disease when orally inoculated at the time of virus challenge. Il has also discovered a new asialoganglioside binding activity in the inner rotavirus capsid that may mediate binding to synthetic asialoneoglycolipid mimetics and inhibition of in vitro infectivity of sialic-acid independent rotaviruses. NE has determined that of five cross-reactive linear B-cell epitopes located within VP5* of bovine group A rotavirus, three had cross-neutralizing activity between bovine rotaviruses with P7[5] and P6[1] serotype [genotype]. Salmonella MN has studied the frequency of phase variation among different strains. Highly virulent isolates SL1344 and I4028 were able to phase vary from on to off at the same frequency. Phase variation from off to on, however, was 100-fold more frequent in the highly virulent strains SL1344 and I4028 as compared to strain 798. Thus, while 798 can be stably maintained in both phenotypic phases, SL1344 and I4028 tend to stay in the virulent on phase. Also, the degree of invasiveness is higher in 798 cells in the on phase compared to the off phase. Strain 798 in the on phase were more invasive than either SL1344 or I4028 and mutations in hilA knocked out invasiveness in all three strains. Transmissible Gastroenteritis Virus and Porcine Respiratory Coronavirus OH found 4 nucleotide changes between fecal and nasal PRCV strains, two of which result in amino acid changes. When the isolated strains were compared with reference strains, one amino acid change was found in all strains and would suggest that the loss of the respiratory tropism of the fecal isolate could be a consequence of the change in this amino acid. Torovirus OH determined the prevalence, fecal shedding patterns and association of Bovine Torovirus with diarrhea in veal calves in 2 0H farms. Calves seronegative or with low antibody titers to BoTV at arrival seroconverted to BoTV and were more likely to shed virus than those already seropositive at arrival. Objective 2. Develop and improve diagnostics, treatment, and preventative measures for enteric and food borne diseases Brachyspira NE has developed a new method for differentiation of Brachyspira species of intestinal spirochetes by cellular fatty acid analysis. NE has also assessed the specificity of the serum IgG response in the context of recovery from and persistent infection by Brachyspira. Coronavirus KS tested the ability of unique commercial decontamination formulations to inactivate bovine coronoviruses as a model system for SARS-like viruses. Cryptosporidium IL has demonstrated that vegetative buffer strips dramatically reduce surface runoff and near-surface flow of oocysts as compared to bare soil surfaces for all rainfall intensities and soil slope conditions. Escherichia coli NE has conducted a clinical trial to test the effectiveness of vaccinating feedlot cattle against enterohemorrhagic E. coli O157:H7 type III secreted proteins on the proportion of feedlot steers shedding the respective organism in the feces. NE also conducted a clinical trial to test the effectiveness of feeding a Lactobacillus acidophilus direct-fed microbial to prevent feedlot cattle from shedding Escherichia coli O157:H7 in the feces. SD has assessed the distribution and significance of EAST1 genes in enterotoxigenic E. coli. The results were very similar to the reported prevalence of EAST1 in Asia and Europe and suggested that EAST1 may not be a major contributor to virulence in ETEC infection in young pigs. SD studied antibody repertoire development in fetal and neonatal piglets. Lawsonia intracellularis MN has evaluated the efficacy of hyper-immunized chicken eggs for the passive immunization protection of hamsters against LI challenge. MN also comparatively evaluated the efficacies of on-label, in-feed antimicrobials for control of PE. All three medications (BMD plus Aureomycin, Tylan, Lincomix) gave significant numerical reductions in the incidence and severity of ileal/jejunal lesions compared to the nonmedicated controls. None of the medications significantly affected seroconversion or the incidence of immuohistochemical-positive pigs. All treatments prevented any PE-related mortality, while 15% of the nonmedicated pigs died. In further studies, MN showed that carbadox inhibited the development of long-term immunity in pigs while protecting them from disease during initial inoculation. Newly Recognized Enteric Viruses and Caliciviruses OH generated recombinant baculoviruses expressing the capsid gene of a bovine norovirus and confirmed that the expressed protein self-assembled into VLPs. The ELISA developed detected BEC antibodies from BEC infected calves. Real-time PCR assays were developed by MI for rapid and sensitive diagnosis of the NB-BEC. Genetic characterization of MI and WI bovine noroviruses by MI based upon sequence analysis of a variable portion of the capsid gene showed that five were Jena-like and seven were NA-2-like. Rotavirus IL has demonstrated that a synthetic receptor mimec of the natural porcine rotavirus receptor, GM3 ganglioside, was able to protect pigs from diarrheal disease when given orally. NE, in collaboration with SDSU, characterized the specificity of hybridoma supernatants containing monoclonal antibodies directed against each of the five VP5* epitopes of bovine RV identified in previous studies. Brachyspira NE further developed a NADH oxidase gene PCR-based RFLP method for identification of Brachyspira from different hosts. NE also determined penicillin binding proteins (PBPs) are present in B. pilosicoli using ampicillin conjugated to digoxigenin and immunoblot chemiluminescent assays. Objective 3. Provide training and continuing education opportunities and dissemination of information MN has given presentations and updates on PE at various scientific, veterinary, and diagnostic meetings in the previous year. In addition, they have presented two international workshops, including theoretical lectures and practical laborabories, on the diagnosis and control of PE. The L. intracellularis specific polyclonal and monoclonal antibodies have been made available to diagnostic laboratories and educational institutions for use in diagnosing PE. Students associated with the OH project are receiving training in the various research areas and with the pathogens specified. The techniques and primers for the RT-PCR assays for differentiation of PRCV and TGEV and detection of BoTV are being transferred to our state diagnostic veterinary laboratory for routine use. A talk on coronaviruses was presented to update veterinarians on bovine coronavirus and bovine torovirus enteric and respiratory disease problems in cattle in the field.

Publications

Publications jointly authored with other stations. Sargeant, J., and D. R. Smith. 2002. Chapter 15. The epidemiology of Escherichia coli O157:H7. In, Torrence, M.E. and R.E. Isaacson (eds.), Microbial Food Safety in Animal Agriculture: Current Topics. Iowa State University Press, pp. 131-141. Publications Berberov, E.M., Y. Zhou, D.H. Francis, M.A. Scott, S.D. Kachman, and R.A. Moxley. 2003. Relative importance of heat-labile enterotoxin in the causation of severe diarrheal disease in the gnotobiotic piglet model by a strain of Escherichia coli that produces multiple enterotoxins. Infection and Immunity (submitted) Bergner, D., TB Kuhlenschmidt and MS Kuhlenschmidt . Characterization of a Synthetic Receptor Mimetic for Group A Porcine Rotavirus (submitted). Burkey TE, Dritz SS, Nietfeld JC, Minton JE. Effect of dietary mannanoligosaccharide and sodium chlorate on the growth performance, acute phase response and bacterial shedding of weaned pigs challenged with Salmonella enterica Serotype Typhimurium. J Anim Sci (submitted). Butler, J.E., P. Weber, M. Sinkora, D. Baker, A. Schoenherr, B. Mayer and D. Francis. 2002. Antibody repertoire development in fetal and neonatal piglets. VIII. Colonization is required for newborn piglets to make serum antibodies to T-independent and type 2 T-independent antigens. J. Immunology. 169: 6822-6830. Chang, K.O., Y. Kim, K.Y. Green and L.J. Saif. 2002. Cell culture propagation of porcine enteric calicivirus mediated by intestinal contents is dependent on the cyclic AMP signaling pathway. Virology 304:302-310. Duhamel, G.E., C.J. Stryker, G. Lu, V.J. Wong, and R.P. Tarara. 2003. Colonic spirochetosis of colony-raised rhesus macaques associated with Brachyspira and Helicobacter. Anaerobe 9:45-55. Guedes, RM.C. and GebhaIt, C.J. 2003. Preparation and characterization of polyclonal and monoclonal antibodies against Lawsonia intracellularis. J. Vet. Diag. Investi. 15:438 446. Guedes, RM.C. and Gebhart, C.J. 2003. Comparison of pure culture of Lawsonia intracellularis and intestinal mucosa homogenate as challenge models for porcine proliferative enteropathy. Vet. Microbiol. 93:159 166 Guedes, RM.C. and Gebhart, C.J. 2003. Onset and duration of fecal shedding, cell mediated and humoral immune responses after challenge with a pathogenic isolate or a commercial vaccine of Lawsonia intracellularis. Vet. Microbiol. 91:135 145. Guedes, R.M.C., Winkelman, N L., and Gebhart, C.J. 2003. Relationship between the severity of porcme proFferative enteropathy and the infectious dose of Lawsonia intracellualaris. Vet. Rec. 153:432 433. Guo, M. and L.J. Saif. 2002. Pathogenesis of enteric calicivirus infections. In Viral Gastroenteritis, (U. Desselberg and J. Gray, eds.) Elsevier Science, Amsterdam, The Netherlands, pp. 489-504. Guo, M., J. Vinje and L.J. Saif. 2002. Caliciviruses and other potential foodborne viruses. In Current Topics in Food Safety in Animal Agriculture, (R. Isaacson and M.E. Torrence, eds.), Iowa State Univ. Press, Ames, Iowa, pp. 333-350. Johnson, JK, Schmidt, J,Gelberg, HB and Kuhlenschmidt MS. (2004) Microbial Adhesion of Cryptosporidium parvum sporozoites: Purification of an Inhibitory Lipid from Bovine Mucosa. J. Parasitol. (in press) Khaitsa, M.L, D.R. Smith, J.A. Stoner, A.M. Parkhurst, S. Hinkley, T.J. Klopfenstein, and R.A. Moxley. 2003. Incidence, duration and prevalence of Escherichia coli O157:H7 fecal shedding by feedlot cattle during the feeding period. Journal of Food Protection 66:1972-1977 Maes, R. K., D.L. Grooms, A.G. Wise, C. Han, V. Ciesicki, L.Hanson, M.L. Vickers and R. Holland. 2003. Evaluation of a Group A Rotavirus Assay for On-Site Detection of Bovine Rotavirus. J. Clin. Micro. 41; 290-294 Marsteller T.A., Annbruster, G., Bane, D.P., Gebhart, C.J., et al. 2003. Monitoring the prevalence of Lawsonia intracelluiaris IgG antibodies using serial sampling in grow~mg and breeding swine herds. J. Swine Health and Prod. 11:127 130. Moreno B, Bailey BN, Luo S, Martin MB, Kuhlenschmidt M, Moreno SN, Docampo R, Oldfield E. (2001) (31)P NMR of apicomplexans and the effects of risedronate on Cryptosporidium parvum growth. Biochem Biophys Res Commun. 284:632-7 Potter, A.A., S. Klashinsky, Y. Li, E. Frey, H. Townsend, D. Rogan, G. Erickson, S. Hinkley, T. Klopfenstein, R.A. Moxley, D.R. Smith, and B.B. Finlay. 2004. Decreased shedding of Escherichia coli O157:H7 by cattle following vaccination with type III secreted proteins. Vaccine Vol. 22, issues 3-4 (In press) Raphael, B.H. and L.A. Joens, 2004. Ferrous lron Uptake if Independent of FeoB in Campylobacter jejuni. Can. J. of Micro. In press. Ristevski, B., Young, A.J., Dudler, L., Cahill, R.N.P., Kimpton, W., Washington, E., Hay, J.B. (2003) Instantaneous labeling of the total blood leukocyte pool to track the development and migration of rare cell types in vivo. International Immunol. 15(2):159-165. Secomb, T.W., Konderding, M.A., West, C.A., Su, M., Young, A.J., Mentzer, S.J. (2003) Microangiectasias: Structural regulators of lymphocyte transmigration in inflammatory skin. Proc. Nat. Acad. Sci. 100(12):7231-7234. Smith, D.R., J. Gray, R. Moxley, S. Younts, M. Blackford, S. Hinkley, L. Hungerford, T. Milton, T. Klopfenstein. 2004. A novel diagnostic strategy to classify feedlot pens by the percentage of cattle shedding Escherichia coli O157:H7. Epidemiology and Infection (in press) Su, M., West, C.A., Young, A.J., He, C., Konerding, M.A., Mentzer, S.J. (2003) Dynamic deformation of migratory efferent lymph-derived cells "trapped" in the inflammatory microcirculation. J. of Cell. Physiol. 194(1):54-62. Trask, JR, Kalita, PK, Kuhlenschmidt, MS, Smith, RD and TL Funk. Overland and Near-surface Transport of Cryptosporidium parvum. 2004. Environ. Qual. (in press) Wise, A.G., S.S. Monroe, L.E. Hanson, D.L. Grooms, D. Sockett and R.K. Maes. 2003. Molecular characterization of noroviruses detected in diarrheic stools of Michigan and Wisconsin dairy calves: Circulation of two distinct subgroups. (submitted). Young, A.J., Holzgreve, W., Dudler, L., Schoeberlein, A., Surbek, D. (2003) Engraftment of human cord blood-derived stem cells in preimmune ovine fetuses after ultrasound-guided in- utero transplantation. .Am. J. Gynecol. Obstet. (In Press) Theses Burkey TE. Effect of dietary mannanoligosaccharide and sodium chlorate on the growth performance, acute phase response and bacterial shedding of weaned pigs challenged with Salmonella enterica Serotype Typhimurium. Thesis for Master of Science. Department of Animal Sciences and Industry, Kansas State University, Manhattan, KS 2003. Brands, D.A. 2003. Thesis. The prevalence and molecular characterization of Salmonella spp. in oysters. University of Arizona, Tucson. Lee, M.K. 2003. Thesis. Presence, potential virulence and antibiotic susceptibility of Campylobacter jejuni isolated from food and companion animals. University of Arizona, Tucson. Pitts, T.M. 2001. Thesis. Intra-macrophage survival of Carn~ylobacter jejuni and maturation of C. jejuni containing phagosomes. University of Arizona, Tucson. Raphael, B.H.. 2002 Thesis. Iron uptake systems of Campylobacter jejuni. University of Arizona, Tucson. Zhang, R., MS Thesis, 2003, University of Nebraska-Lincoln, Comparative analysis of membrane proteins of human and animal Brachyspira species. Book Chapters: Moxley, R.A. 2003. Detection and diagnosis of Escherichia coli O157:H7 in food-producing animals. In, Torrence, M.E. and R.E. Isaacson (eds.), Microbial Food Safety in Animal Agriculture: Current Topics. Iowa State University Press, pp. 143-154. Abstracts/Proceedings: Al Ghamdi, G.M., R.M.C. Guedes, T.R Ames, and C.J. Gebhart. 2002. Reproduction of proliferative enteropathy in foals after challenge with Lawsonia intracellularis infected porcine mtestinal mucosa homogenate. Proc. 83rd Conf. Res. Workers An. Dis., St. Louis, MO, November 10 12 Alsop, J., J. Harding, V. Costantini, P. Lewis and L.J. Saif. A trial to determine true TGE status in a multiplier herd. Int. Pig Vet. Symposium, Ames, IA, June 2-5, 2002. Baker, D.R., R.A. Moxley and D.H. Francis. 2003. Amount of Shiga toxin type 2 (Stx2) expressed by Escherichia coli O157:H7 strains in vitro is correlated with virulence in the gnotobiotic piglet model. Proceedings, 84 Annual Meeting of the Conference of Research Workers in Animal Diseases. Chicago, IL. Beckler, D.C., C. Mahlum Wees, RM.C. Guedes, and C.J. Gebhart. 2003. Development and comparison of tests for detecting fecal shedding of Lawsonia intracellularis. 34th Annual Mtg. Am. Assoc. Swine Veterinarians, March 8 11, Orlando, FL. Carvajal, A., M.L. De Arriba, H. Rodriguez, A.B. Vidal, G.E. Duhamel, and P. Rubio. 2003. Prevalence of Brachyspira hyodysenteriae and B. pilosicoli infections among spanish swine herds with diarrhoea. 2nd International Conference on Colonic Spirochaetal Infections in Animals and Humans, Edinburgh, United Kingdom, April 2-4, p. 43. Chang, K-O., S. Sosnovtsev, G. Belliot, L.J. Saif, and K.Y. Green. 2003. Generation and characterization of infectious RNA transcripts of porcine enteric calicivirus in cell culture. 22nd Annual Meeting of the Conference of American Society for Virology, Davis, CA, Abst. July 12-16, 2003. Costantini, B., F. Loisy, J. Joens, F. LeGuyader and L.J. Saif. Calicivirus survey in U.S. Market oysters: preliminary findings. 22nd Annual Meeting of the Conference of American Society for Virology, Davis, CA, Abst. July 12-16, 2003. Dassanayake, R.P., N.E. Caceres, G. Sarath, and G.E. Duhamel. 2003. Biochemical properties of membrane-associated proteases of Brachyspira pilosicoli isolated from humans with intestinal disorders. 2nd International Conference on Colonic Spirochaetal Infections in Animals and Humans, Edinburgh, United Kingdom, April 2-4, p. 37. Dassanayake, R.P., G. Sarath, and G.E. Duhamel. 2003. Identification of penicillin-binding proteins (PBPs) in membrane extracts of Brachyspira pilosicoli. 84th Annual Meeting Conference Research Workers in Animal Diseases, St. Louis, Missouri, November 9-11, P (Poster). Duhamel, G.E. 2003. Diagnostic procedures for colonic spirochaetal infections, where have we been and where are we going? 2nd International Conference on Colonic Spirochaetal Infections in Animals and Humans, Edinburgh, United Kingdom, April 2-4, p.13. Duhamel, G.E., and K. Tarasiuk. 2003. Phenotypic and genotypic characterization of Brachyspira pilosicoli isolated from humans with intestinal disorders. 2nd International Conference on Colonic Spirochaetal Infections in Animals and Humans, Edinburgh, United Kingdom, April 2-4, p. 27. Duhamel, G.E., T.K. Jensen, M. Boye, and K. Møller. 2003. Comparative pattern of spirochetal colonization in naturally-occurring swine dysentery and porcine colonic spirochetosis. 2nd International Conference on Colonic Spirochaetal Infections in Animals and Humans, Edinburgh, United Kingdom, April 2-4, p. 48. Duhamel, G.E., K. Sestak, C.J. Stryker, G. Lu, and A.A. Lackner. 2003. Colonic spirochetosis of colony-raised rhesus macaques is a polymicrobial disease associated with multiple species of Brachyspira and Helicobacter. 84th Annual Meeting Conference Research Workers in Animal Diseases, St. Louis, Missouri, November 9-11, O (Oral). Duhamel, G.E., C. Fellström, C.J. Stryker, M. Alexander, A. Gunnarsson, and G. Osterhout. 2003. Characterization of canine Brachyspira by cellular fatty acid analysis and pulse-field gel electrophoresis. 2nd International Conference on Colonic Spirochaetal Infections in Animals and Humans, Edinburgh, United Kingdom, April 2-4, p. 34. Duhamel, G.E., C.J. Stryker, and Y.J. Zhou. 2003. Demonstration of Brachyspira pilosicoli association with canine colonic spirochetosis and B. canis as a non-pathogenic commensal. 2nd International Conference on Colonic Spirochaetal Infections in Animals and Humans, Edinburgh, United Kingdom, April 2-4, p. 20. Duhamel, G.E., L. Ganley, B.C. Barr, J.P. Whipple, R.W. Nordhausen, R.L. Walker, and H.J. Van Kruiningen. 2003. Colonic spirochetosis of North American opossums (Didelphis virginiana): A potential reservoir of infection for humans and animals. 2nd International Conference on Colonic Spirochaetal Infections in Animals and Humans, Edinburgh, United Kingdom, April 2-4, p. 42. Fegan N, Higgs GM, Vanderlinde P, Desmarchelier P, Smith DR. 2003. Pen test devices for detection of E. coli O157 and Salmonella in cattle. VTEC 2003. Edinburgh, Scotland, UK. June 8-11, 2003. Poster Folmer, J., C. Macken, R. Moxley, D. Smith, M. Brashears, S. Hinkley, G. Erickson, and T. Klopfenstein. 2003. Intervention strategies for reduction of E. coli O157:H7 in feedlot steers. 2003 Nebraska Beef Report. Agricultural Research Division, University of Nebraska Cooperative Extension, Institute of Agriculture and Natural Resources, University of Nebraska-Lincoln, pp. 22-23, http://animalscience.unl.edu/beef/beef.htm. Gebhart, C J., Winkolmm, N, Deen, J , and Gramm~ B. 2003. Development of mmmity to Lawsonia intracellulans in pigs fed carbadox. 34th Aunual Mtg. Am. Assoc. Swine Veterinarians, March 8 11, Orlando, FL. Gebhart, C.J., L.L. Li, Q. Zhang, L.L. Heron, and V. Kapur. 2002. A genomic sequence survey of Lawsonia intracellularis identifies numerous genes of relevance to diagnosis, virulence, and immunoprophylaxis. Proc. 83rd Conf. Res. Workers An. Dis., St. Louis, MO, November 10 12. Graybill, M.D., Elmubaruk, G., DeRycke, M.S., Young, A.J. 2003. Role of soluble CD14 in the regulation of neonatal ovine B cell differentiation and expression. Proceedings, Autumn Immunology Conference. Chicago, IL Guedes, RM.C. and C.J. Gebhart. 2003. Progression of Lawsonia intracellularis infection and mucosa immune response in pigs. 34th Annual Mtg. Am. Assoc. Swine Veterinarians, March 8 11, Orlando, FL. Guedes, R.M.C., C. J. Gebhart, and G.A. Armbruster. 2002. Progression of Lawsonia intracellularis infection in experimentally infected pigs. Proc. 83rd Conf. Res. Workers An. Dis., St. Louis, MO, November 10 12. Guedes, R.M.C. and C.J. Gebhart. 2002. Production and characterization of new polyclonal and monoclonal antibodies for Lawsonia intracellularis. 29th Allen D. Leman Swine Conference, Minneapolis, MN, September 15 17. Gwyn, C.B., and G.E. Duhamel. 2003. Porcine colonic spirochetosis caused by Brachyspira pilosicoli. Swine Health Symposium, Stratford, Ontario, Canada, May 16-18, p. 5-12. Han, M.G., Q. Wang, J.R. Smiley and L.J. Saif. 2003. Self-assembly of recombinant capsid proteins of a bovine norovirus into virus-like particle (VLP). 22nd Annual Meeting of the Conference of American Society for Virology, Davis, CA, Abst. July 12-16, 2003 Hoet, A.E., S. Sreevatsan and L.J. Saif. Molecular analysis of the 5' end of the spike gene of bovine torovirus (breda virus) field strains. Am. Soc. Virol., Lexington, KY, July 20-24, 2002. Johansson, K.E., G.E. Duhamel, B. Bergsjö, E.E. Olsson, M. Persson, B. Pettersson, and C. Fellström. 2003. Phylogeny of canine intestinal spirochetes based on 16S rDNA analysis. 2nd International Conference on Colonic Spirochaetal Infections in Animals and Humans, Edinburgh, United Kingdom, April 2-4, p. 33. Kinsley, K., C. J. Gebhart, N. WinkeEnan, and R.M.C. Guedes. 2003. Passive immunization of hamsters using hyperimmunized chicken eggs to control Lawsonia intracellularis infection: a model for growing swine. 34th Aonual Mtg. Am. Assoc. Swine Veterinarians, March 8 11, Orlando, FL. Kolappaswamy, K., Y.J. Zhou, and G.E. Duhamel. 2003. Attachment of Brachyspira pilosicoli to cultured intestinal epithelial cell lines. 34th Midwest Student Biomedical Research Forum, Omaha, Nebraska, February 21-22, P-14 (Poster). Moxley1, R.A., D. R. Smith1, T. J. Klopfenstein2, J. D. Folmer2, C. N. Macken2, G. E. Erickson2, S. Hinkley1, A. A. Potter3, and B. B. Finlay4. 2003. Vaccination and direct-fed microbials as intervention strategies to reduce the prevalence of Escherichia coli O157:H7 in feedlot cattle. 1Dept. of Vet. & Biomed. Sci., 2Dept. of Animal Sci., U. of Nebraska, Lincoln, NE. 3Vaccine & Infectious Disease Org., U. of Saskatchewan, Saskatoon, Saskatchewan, Canada. 4Biotechnology Laboratory, U. of British Columbia, Vancouver, BC, Canada. 84th Annual Meeting Conference Research Workers in Animal Diseases, Chicago, Illinois, Nov. 9-11. Abstract 82 (Oral). Moxley, R.A. 2003. Escherichia coli O157:H7: an update on intestinal colonization and virulence mechanisms. Dept. of Vet. & Biomed. Sci., U. of Nebraska, Lincoln, NE. 84th Annual Meeting Conference Research Workers in Animal Diseases, Chicago, Illinois, Nov. 9-11. Abstract 92 (Oral, keynote). Nielsen, P.R., Y. Kim, K.O. Chang and L.J. Saif. Passive protection of neonatal calves against challenge with bovine rotavirus by colostrum supplements from cows vaccinated with a combination of bovine rotavirus-like particles against one or both prevalent U.S. serotypes. Conference for Research Workers in Animal Disease. St. Louis, MO, November 10-12, 2002. Rice MA, Fang Y, Ambagala APW, Ambagala TC, Srikumaran S, Nelson EA, Duhamel GE. 2003.Characterization of monoclonal antibodies specific for linear B-cell epitopes located within bovine group A rotavirus VP5* . 84th Annual Meeting Conference Research Workers in Animal Diseases, St. Louis, Missouri, November 9-11, P (Poster). Rohlik, A., DeRycke, M., Young, Alan J. 2003. Identification and Characterization Of Leukocyte Populations In Hoofstock; A tool for the study of Chronic Wasting Disease (CWD) Proceedings, Autumn Immunology Conference. Chicago, IL Ruesch, L.L., R.L. VanderVeen and D.H. Francis. 2003. Enteroaggregative Escherichia coli heat-stable enterotoxin 1 (EAST1) and its occurrence in enterotoxigenic E. coli strains causing diarrheal disease. Proceedings, 84 Annual Meeting of the Conference of Research Workers in Animal Diseases. Chicago, IL. Saif, L.J., M. Guo and J. Smiley. Enteric caliciviruses in pigs and calves and their relationship to human caliciviruses. Brazil Soc. Virol., Caldas Novas, Goias, Brazil, Nov. 25-28, 2001. Saif, L.J. 2002. Coronaviruses: Update on diagnosis, pathogenesis and control of bovine coronavirus-associated calf diarrhea, winter dysentery and shipping fever. Abst. Iowa Veterinary Medical Association Meeting, September 12, 2002, Ames, Iowa. Smiley, J.R., K.O. Chang, and L.J. Saif. Complete genome sequence of a bovine enteric calicivirus genogroup. Conference of Research Workers in Animal Disease, Abst. #117, St. Louis, MO, Nov. 12-13, 2001. Smiley, J., K. Chang, J. Vinje and L.J. Saif. Genomic characterization of the enteropathogenic bovine caliciviruses: CV95/OH, CV186/OH and NB strain-a prototype virus of a new calicivirus genogroup. Am. Soc. Virol., Lexington, KY, July 20-24, 2002. Smith DR. 2003. Feedlot epidemiology of E. coli O157H7 bridging the gaps. Second Governor's Conference on Escherichia coli. Lincoln, NE. April 7-8, 2003. Oral. Thomas, C., A.E. Hoet, J. Smiley, P. R. Nielsen, T. Wittum and L.J. Saif. Association of bovine torovirus with veal calf diarrhea. Conference for Research Workers in Animal Disease. St. Louis, MO, November 10-12, 2002. Trask, JR, Kalita, PK, Kuhlenschmidt, MS, Smith, RD and TL Funk. Overland and Near-surface Transport of Cryptosporidium parvum. 2001. Annual American Society For Agricultural Engineering, Paper Number 01-2104. Wang, Q.H., M.G. Han, A.E. Hoet, and L.J. Saif. Hemagglutination by Cowden porcine enteric calicivirus and development of hemagglutination-inhibition test. Conference for Research Workers in Animal Disease. St. Louis, MO, November 10-12, 2002. Wang Q.H., M. Guo and L. J. Saif. 2003. Serum neutralizing and isotype antibody responses in gnotobiotic (Gn) pigs inoculated orally with tissue culture-adapted (TC) or wild type (WT) porcine enteric calicivirus (PEC). 22nd Annual Meeting of the Conference of American Society for Virology, Davis, CA, Abst. July 12-16, 2003. Ward, J.J., RD. Smith, MS Kuhlenschmidt. 2002. Evaluation of Factors Contributing to Environmental Contamination with Cryptosporidium parvum from a Dairy Herd. International Conference on Emerging Infectious Diseases, March 2002, Atlanta, Ga. Whitney, M.H., G.C. Shurson, R.M.C. Guedes, and C.J. Gebhart. 2002. The relationship between distiller's dried grains with solubles (DDGS) and ileitis. Min. Nutrition Conf ~ Pre Conf Symposium: Rendering a foundation for food security. Eagan, MN, p.244 256. Winkelman, N., Gebhart, C.J., Wolff, T., and Skinner, J. 2003. An evaluation of BMD plus Aureomycm chlortetracycline (CTC), Tylan or Lmcomix for control of challenge induced PPE m swine. 34th Annual Mtg. Am. Assoc. Swme Veterioarians, March 8 11, Orlando, FL. Winkehman, N., Gebhart, C.J., Deen, J., and Gramm, B. 2003. Correlation of clinical signs and diagnostic indicators of ileitis in pigs fed carbadox. 34th Aunual Mtg. Am. Assoc. Swine Veterinarians, March 8 11, Orlando, FL Wise, A. G., L. Hanson, D. Grooms and R. Maes. 2002. Detection and molecular characterization of bovine Norwalk-like viruses in diarrheie stools collected from Michigan and Wisconsin dairy calves. Proc. of the American Association of Veterinary Laboratory Diagnosticians 45th Annual Meeting, St. Louis, MO 2002. p. 9. Young, A.J., Richt, J., Hamir, A. 2003. A potential role for B cell subsets in the pathogenesis of Prion Disease. Proceedings, 84 Annual Meeting of the Conference of Research Workers in Animal Diseases. Chicago, IL. Zhang, W., J. Freeling, E. Berberov, R. Moxley and D. Francis. 2003. Development of a model for the assessment of the contributions of E.coli enterotoxins to the pathogenesis of porcine colibacillosis. Proceedings, 84 Annual Meeting of the Conference of Research Workers in Animal Diseases. Chicago, IL. Zhang, R., and G.E. Duhamel. 2003. Comparative analysis of pathogenic and commensal porcine Brachyspira species membrane proteins. 2nd International Conference on Colonic Spirochaetal Infections in Animals and Humans, Edinburgh, United Kingdom, April 2-4, p. 46.

Impact Statements

Work by NC-1007 members during the past year added to the understanding of pathogenic mechanisms and immunity to several enteric pathogens. Specifically, identification of virulence genes, production of strains with mutations in these genes, sequencing the genome, and pathogenesis studies added to our understanding of how B. pilosicoli, Escherichia coli, C. parvum, C. jejuni, porcine coronaviruses, and rotavirus are able to colonize and invade mucosal surfaces, cause disease, and survive in mac
NC-1007 researchers identified compounds that hold promise in prevention and treatment of disease caused by agents such as B. hyodysenteriae, rotavirus, C. parvum, E. coli L. intracellularis and Salmonella.
Studies have helped to define the immune responses to agents such as B. hyodysenteria, L. intracellularis, E. coli O157:H7, C. parvum, and rotavirus which will help in designing and developing vaccines, control measures, and improved diagnostic assays.

Date of Annual Report: 02/09/2005

Report Information

Annual Meeting Dates: 11/13/2004 - 11/14/2004
Period the Report Covers: 10/01/2003 - 09/01/2004

Participants

Technical Committee Members and Attendees - Institution or Station;

Lynn A. Joens* - Arizona;
(Mark Kuhlenschmidt*) -Illinois;
Sanjay Kapil, Bruce Schultz, Frank Blecha, Don Robertson - Kansas;
Roger Maes* - Michigan;
Connie Gebhart* (Chair), Richard Isaacson - Minnesota;
Rodney Moxley* - Nebraska;
Srinard Sreevastsan (for Linda Saif*) - Ohio;
David Francis* - South Dakota;
Thomas Besser - Washington;

Bert Stromberg - Administrative Advisor;
Mary Torrence - CSREES Mary;

Not represented: Illinois, Indiana, Iowa, Missouri;
*Voting member of Technical Committee

Brief Summary of Minutes

Agenda:

Saturday, November 13
8:00 AM Registration and Continental Breakfast
8:30 AM Meeting Call to Order and Introduction of Members and
Guests
8:45 AM Opening Remarks by Dr. Bert Stromberg, NC 1007 Administrative Advisor
9:00 AM CSREES Report by Dr. Mary Torrence
9:15 AM Interdisciplinary Project Report and Planning Session, led by Dr. Isaacson
10:00 AM Break
10:30 AM Rushmore Conference Update and Planning Session, led by Dr. Francis

Progress Reports and Principal Accomplishments
11:00 AM Coronavirus, Rotavirus, Other Viral Enteric Pathogens
Moderator: Dr. Kapil
11:30 AM: Campylobacter, Lawsonia
Moderator: Dr. Joens
12:00 PM: Lunch
1:00 PM: Brachyspira
Moderator: Dr. Gebhart
1:20 PM: Salmonella
Moderator: Dr. Isaacson
1:40 PM: Escherichia coli
Moderator: Dr. Moxley
2:10 PM Break
2:40 PM Cryptosporidium
Moderator: Dr. Gebhart
3:00PM Discussion of Strategic Concerns
5:00PM Adjourn

Saturday, November 14
8:00 AM Business meeting of Technical Committee Members
9:00AM Announcements
9:30 AM Discussion of Cooperative Research for Next Year
12:00 PM Adjourn

Summary of the Meeting:

Saturday November 13, 2004
The meeting was called to order by Dr. Gebhart at 8:30 AM. The list of NC1007Station Representatives and Collaborators was circulated for updates. The minutes from last years meeting were distributed and approved. The Fall 2004 NCRA Regional Update Newsletter was distributed. Meeting dues were briefly discussed. It was decided to keep the dues at $50.00.

Under the heading old business, there was discussion on the need for industry support and the fact that this issue should be re-addressed.

Dr. Stromberg presented his opening remarks. Two years from now we have a project rewrite. He stressed that project review has been changed. It will be very important to show that there is true collaboration between stations, not merely sharing of reagents. The expectation will be that real sharing is evident in the research, for example by multi-institutional publications or multi-state proposals. Another important consideration will be meeting attendance. Participants should focus on presenting rationale and impact of their work. Through discussion, we should define our longer term goal and ways to effectively interact. He suggested submission of a multi-state proposal to NRI. Realizing this agencys restricted funding, it would be important to know which entities they want to focus on.

Dr. Mary Torrence, CSREES representative, stated that the focus of her agency is food safety. The NRI budget has increased slightly and the number of priority areas has been reduced from 8 to 3-4. This will have a positive impact on the size of the awards. She reiterated her suggestion to submit a large collaborative research proposal to either NRI or NIH. Another possibility would be to apply for a CAP award. The focus of the CAP or network awards is currently also on food safety, at the expense of the epidemiology program. Flexibility towards emerging issues is important. She pointed to the success of the PRRS group in obtaining a CAP award and said that this committee had the same potential for obtaining this type of award. What is important to be successful in these endeavors is to think differently, to de-emphasize individual grants and to focus on impact and outcome.

Dr. Isaacson led a discussion aimed at generating ideas for a group project. He emphasized that it will be necessary to think big and think different. He mentioned that he sent out an e-mail message to solicit input for a pre-proposal, but that the response from the group was very limited. Despite this, he said that he did submit a proposal on changes in the microflora of the gut in response to antibiotics. The proposal was not funded, but will be resubmitted with a revised epidemiological component. It was pointed out that important elements for the success of the PRRS group in obtaining a grant were the formation of partnerships leading to real collaboration, a multistate approach, looking at outcomes and bringing in the Pork Producers organization. Dr. Isaacson pointed out that it is important to come up with things that unite us. Dr. Gebhart suggested to focus on a few areas of expertise, with 1-2 investigators per area. Dr. Torrence mentioned that some groups use a piece-by- piece approach, rather than submitting an all-encompassing proposal. Dr. Gebhart suggested looking at antibiotics in the feed versus the problem of taking antibiotics out of the feed. After some further discussion, Dr. Isaacson focused on what appeared to be the most productive idea: definition of the normal gut flora in the presence or absence of antibiotics. Dr. Torrence mentioned that CDC involvement might be feasible for this type of project. Dr. Isaacson then gave a brief overview of the approaches he had taken to gather preliminary data for this type of project. Dr. Stromberg asked how we would all fit in. Dr. Isaacson suggested to use the remainder of the day for further brainstorming.

Dr. David Francis announced that the Third International Rushmore Conference will be held on September 30 and October 1, 2005 at the Rushmore Plaza Hotel in Rapid City, SD. The suggested conference title is: Strategies in the Prevention of Enteric Disease and Dissemination of Food-Borne Pathogens Currently secured funds total $15,000. This meeting is to be viewed as an important part of the outreach component of the NC-1007 group. The focus of this meeting will be less on mechanisms of disease than what are we going to do about it. Four sessions are proposed. Each session will be composed of a keynote address and one or more internal and external invited presentations. The following points were made on meeting format and proceedings:
-Not every speaker has to be interested in enteric diseases.
-The focus of the meeting should not be limited to veterinary medicine.
-Oral presentations should primarily be given by the invited speakers. These will be of the overview type. Most other presentations, except for 4-5, which will be converted to oral presentations, will be presented as posters.
-Dr. David Francis will put the conference grant together.
-Does the series Advances in Experimental Medicine still exist?
-A draft of the meeting format was distributed.
-Nominations are needed for speakers. The names of potential speakers should be submitted to Dr. Francis via e-mail.
-Dr. Francis suggested inviting people from major granting agencies to come talk to us in conjunction with this meeting.
-A website would be very useful.

From 11:00 AM on participants from the stations represented at the meeting discussed overview presentations of progress and principal accomplishments made during the last year on the project(s) they were associated with.

Starting at 3 PM, the discussion of strategic concerns was continued. Dr. Isaacson recapped the morning discussion and acted as a facilitator. He proposed to brainstorm ideas and get them on the table. He stressed that responsibilities needed to be defined and an action plan had to be formulated.
Various ideas were put forward, the two main themes being the effects of antibiotics on colonization and the alteration of the gut microflora in response to antibiotics.

General comments
All bacterial pathogens spend most of their life cycle as commensals. What do we know about their relationship with the host? All our efforts are focused on disease aspects, not on the bacterial-host interaction.
Do we have to focus our efforts at the whole animal level?
Growth promoters produce changes in the microflora and enhance/optimize metabolic activity. This enhances the health of an animal in a general sense.
A consortium grant could focus on host factors and individual grants on virulence factors.

Colonization-related ideas
Dr. Joens said that pathogenesis and colonization are the strengths of this group.
Dr. Joens commented on the host-dependent effect of colonization with Campylobacter. Dr. Moxley indicated that E.coli O:157 receptors are present only on certain cell types in cattle, explaining why cattle do not show disease. Dr. Joens mentioned that the host response should not be overlooked and that we have the advantage of animal models of foodborne disease within the group.
Dr. Francis said that biofilm formation, resulting in resistance to antibiotics, is a form of colonization.
Dr. Moxley mentioned quorum sensing in the gut.
Dr. Gebhart proposed colonization as the central theme. Different environmental conditions (presence or absence of antibiotics in the food) and differences between pathogens could be tested within this framework.
Dr. Joens mentioned several angles that could be explored within the colonization framework:
-Receptors versus no receptors.
-Bacterial by-products.
-Tissue environment.
-Expression of bacterial proteins.
-Colonization factors have been studied for more than 30 years.
-What would be new in colonization? To be relevant, what is being proposed has to lead to an intervention strategy.

Alteration of the gut microflora
-Changes in microbial flora are the result of changes in glycosylation.
Dr. Isaacson stated that there are 500-1000 bacterial species in the gut, with tremendous concentration variation between them. Entire population measurement is important
-Healthy animals grow better. Is this a microflora shift?
-Ohio said that a population shift may be difficult to predict, but that the effect of a population shift can definitely be studied
-Because of changes in antibiotic use regulations in Europe, more antibiotics have to be used there now to treat sick pigs.
-Are the tools available to focus the proposal around microflora changes?

Sunday, November 14, 2004
The business meeting of technical committee members was started at 8AM.
The committee decided that the next NC-1007 meeting will take place in Rapid City, SD, after the conclusion of the Rushmore Conference.
The Conference is fulfilling our obligation to disseminate information.
There was discussion on ways to involve industry and commodity groups. One possibility would be to invite representatives from industry and relevant commodity groups to the conference and have an open evening session with them.
Dr. Francis will send out a list of potential invitees. An attempt will be made to get Dr. Gerberding from CDC as a speaker.

The general meeting was started at 9:00AM.

New business
Dr. Gebhart announced the meeting date/place for the next NC-1007 meeting.
Judges were selected for the poster session of the enteric disease section of the CRWAD meeting.
Dr. Joens announced that a new chair will need to be appointed for the Enteric Disease Session of CRWAD. Nominations should be submitted by e-mail by May, 2005.
A keynote speaker is needed for next years Enteric Disease Session. Dr. Linda Saif was mentioned as a potential speaker.

Proposal(s)

1. Microflora
Dr. Gebhart suggested to pursue the microflora approach as our main proposal, since it has already been submitted once by Dr.Isaacson. The objectives would be to look at the effect of growth promoters on gut microflora and the relationship to public health. Dr. Isaacson has contacted another group for a swine model. This group would be specifically mentioned in the proposal.
Other Producer groups (beef, dairy, poultry) should be focused upon.
Dr. Isaacson said that the existing proposal can only be changed in the area of epidemiology.
Dr. Francis said that it is unlikely that everyone from the group is a participant in this proposal.

2. Colonization
Dr. Joens proposed seeking seed money for the colonization approach related to antibiotics (~$50,000) from producer groups. Data obtained with this money could be used to write an NIH proposal.
Dr. Gebhart indicated that she is willing to help in getting industry support for this approach.
Dr. Francis thought that USDA is not likely to fund this type of proposal. He was in favor of seeking industry support and said that we could take advantage of the presence of industry people at next years Rushmore conference. Dr. Gebhart concurred.
Dr. Isaacson said that it would be OK to have a stakeholders meeting during the Rushmore Conference.
Dr. Joens said that the concept was to get seed money so that more people would be involved. Subgroups within the committee could then submit grants, either to NIH or USDA.

3. Conclusions
-Dr. Isaacson will resubmit the microflora proposal.
-Small group collaboratives are planned for next year.
-The group will seek seed money for research, both from industry and producer groups.
-A stakeholders meeting will be held in conjunction with the Rushmore Conference.

Publications
Dr. Stromberg re-emphasized the need for shared publications.

The meeting was adjourned at approximately 12:00 PM.

Next meeting Information:
Location: Rapid City, SD
Date: October 2, 2005

Respectfully submitted,
Roger Maes
NC-1007 Secretary

Accomplishments

Objective 1 Define mechanisms of pathogen-host-environmental interactions in enteric and food borne diseases: Brachyspira The biochemical properties of membrane-associated proteases of B. pilosicoli were investigated by NE. Campylobacter The cytolethal distending toxin (CDT) of Campylobacter species was characterized by NE. Although cdtB gene sequences are present in both C. jejuni and C. coli, production of CDT correlated positively only with C. jejuni. AZ is assesing the pathogenicity of C. jejuni in broilers. Their studies indicate that isolates from poultry exhibit a wide range of virulence traits and suggest that only certain clusters of isolates, a minority, from poultry may be virulent and capable of causing disease in humans. AZ has also isolated novel virulence genes from C. jejuni using a green fluorescence protein promoter library. They continue to explore the environmental factors associated with C. jejuni biofilm development on abiotic surfaces, focusing on the early stages of biofilm development and attachment to surfaces. Lawsonia MN has performed a metabolic reconstruction of Lawsonia based on information derived from the whole genomic sequence. This information may help define necessary nutritional components for cell-free growth of this obligately intracellular bacterium. Also, they have cloned, expressed, and purified a flagellar protein of Lawsonia, FliC. Escherichia coli NE, as a result of preliminary experiments conducted at SD, has constructed a single knockout STb- strain of E. coli using the lambda red recombinase-based linear transformation technique. This will be used to construct double and triple-knockout mutants in porcine origin enterotoxigenic E. coli in order to delete the antibiotic resistance markers following the inactivation of each gene. SD has investigated the factors influencing F18+ E. coli receptor expression in weanling pigs. Their findings suggest that diet and microbial flora may be at least partially responsible for inducing F18+ receptor expression in these pigs. They continue to characterize the receptor specificity of D88ac fimbriae. To date, observations of these studies suggest that several regions of the FaeG genes are likely involved in receptor recognition, with the region from aa133 to 156 imparting variant receptor specificity. WA is studying E. coli O157:H7 excretion over 12 months in dairy heifers with the aim of identifying high versus low shedders, concentrations, and persistence of excretion. They are also examining the role of RAJ colonization in influencing feedlot E. coli epidemiology. This work aims to identify E. coli O157:H7 super-shedders and examine how their presence within a feedlot pen influences the E. coli excretion of in-contact cattle in the same pen. Samples from retail beef and raw milk within WA State for sampled for non-O157:H7 STEC. Isolates obtained have been characterized on the basis of virulence marker possession and serogroup. These food non-O157:H7 isolates are being compared to local human isolates based on genotype, serogroup, and virulence marker profiles. Salmonella Research examining maintenance and transmission of multi-drug resistant S. Newport in dairy herds has been completed by WA. Data indicate that separation of hospital pens and maternity pens is an effective intervention for reducing the prevalence and persistence of these organisms. Also, a new DNA microarray approach has been used for molecular fingerprinting of Salmonella R- plasmids. Porcine Enteric Calicivirus OH identified bile acids as the active factor in intestinal content fluid required for PEC growth. They propose a novel mechanism for enteric calicivirus growth dependent on bile acids, ubiquitous molecules present in the intestine at the site of the virus replication that involves the PKA cell-signaling pathway and a possible down-regulation of innate immunity. Porcine Group A Rotavirus IL pursued a receptor therapeutic approach for porcine rotavirus disease, based on previous studies showing that gangliosides are required by sialic acid-dependent strains for enterocyte infectivity. Since infection of enterocytes is preceded by attachment of virus to the cell surface, it follows that an understanding of the biology of this interaction is seminal to prophylactic or therapeutic intervention. Bovine Coronavirus Several methods were used to detect bovine coronavirus in soil samples by KS and they concluded that this virus was inactivated in the soil environment. They also assessed the effectiveness of several disinfectants on emerging and enteric viruses in the environment, concluding that RNA was relatively more stable than viral proteins and needed longer and higher concentration treatments for complete inactivation. Cryptosporidium parvum IL found that mucins, plasma membrane vesicles and fractioned cell membranes inhibited binding of sporozoites to host cells. They have purified and partially characterized this membrane inhibitory activity which has led to the discovery of a bovine intestinal-derived lipid fraction that inhibits sporozoite infectivity of host cells. Using suppressive subtractive hybridization, they identified a small number of candidate genes that appear to be differentially expressed. These are being cloned and sequenced. Finally, IL has determined the Cryptosporidium oocysts are effectively retarded from overland transport by vegetative filter strips and that the mechanism of this retardation is specific adhesion to the clay particles of the soil that occurs as a consequence of reduced flow over a vegetated surface as compared to bare soil. Objective 2 Develop and improve diagnostics, treatment, and preventative measures for enteric and food-borne diseases: Escherichia coli NE is performing clinical trials to test the effect of an enterohemorrhagic E. coli (EHEC) type III secreted protein vaccine on prevalence of E. coli O157:H7 in a research beef feedyard. The data suggest that vaccinating against EHEC type III secreted proteins has a significant effect on E. coli O157:H7 colonization of the terminal rectum of cattle. NE is also performing a clinical trial testing the effect of a direct-fed microbial product on prevalence of E. coli O157:H7 in a research beef feedyard. This study shows that feeding a combination of Lactobacillus crispatus and Propionibacterium freudenreichii direct-fed microbial product was not effective in reducing the probability of E. coli O157:H7 fecal shedding or colonization of the terminal rectum by this organism. A large-scale clinical trial that tested the effect of EHEC type III secreted protein vaccine and direct-fed microbials on the prevalence of E. coli O157:H7 in commercial beef feedyards was conducted. Vaccination of cattle within commercial feedlots was effective for reducing the probability of detecting E. coli O157:H7 from ROPES and might be beneficial as a pre-harvest intervention strategy against E. coli O157:H7. The effect of the EHEC type III secreted protein vaccine in weanling calves on the ranch was tested for reduction of the prevalence of E. coli O157:H7 in feedlot cattle. They concluded that the prevalence of E. coli O157:H7 during fall weaning was minimal on the Montana ranches tested, and the low level of shedding persisted throughout the feeding period. Therefore, the effect of vaccination as a pre-harvest food safety intervention strategy for backgrounders and feeders could not be determined. SD has developed an optimized multiplex PCR to detect virulence genes in Enterotoxigenic E. coli (ETEC). This test appears to eliminate or substantially reduce incidence of false positive test results. Salmonella AZ examined oysters from U.S. coastal waters for the prevalence of fecal coliforms and Salmonella. S. Newport was the major pathogen isolated at a prevalence rate of 7.8%. Virtually all isolates were resistant to ampicillin and tetracycline. Campylobacter WA performed a survey of thermophilic Campylobacter prevalence on Pacific NW cattle farms of various types. Overall detected prevalence of C. jejuni was about 40% and of C. coli less than 10%. C. coli expressed antimicrobial resistance and multiple antimicrobial resistance much more frequently than did C. jejuni. Lawsonia MN evaluated the effectiveness of hyper-immunized chicken eggs for controlling Lawsonia infection in growing swine and found that these antibodies significantly affected the reduction in average daily gain during a Lawsonia infection. MN also developed and tested a method for molecular epidemiologic typing of Lawsonia. This Variable Number Tandem Repeat typing method was shown to be stable and conserved in individual Lawsonia isolates under various conditions. MN developed and compared two methods for measuring the viability of Lawsonia and found that there was no significant difference between flow cytometry or a direct count method for determining Lawsonia viability. Finally, MN compared the agreement of two Lawsonia serology tests, an indirect fluorescence antibody test and an immunoperoxidase monolayer assay, for sensitivity and specificity in diagnosis of field cases of ileitis. There was an excellent level of agreement between the tests, with a Kappa value of 0.87. Enteric Calicivirus OH conducted a cross-sectional study in normal adult pigs to investigate the prevalence of porcine sapovirus Cowden and porcine noroviruses. The prevalence of porcine Norovirus was 23% and that of porcine Sapovirus was 30%. The high prevalence of these Noroviruses raises the question of whether pigs may be reservoirs for certain strains of human Noroviruses. To determine risk assessments for occurrence of human and animal caliciviruses in U.S. market oysters and to develop strategies to reduce viral gastroenteritis associated with their consumption, OH surveyed regional oyster harvests for caliciviruses. The results confirm the presence of human caliciviruses in raw oysters and suggest that they should be considered a risk factor in outbreak inveastigations. OH also determined both antigenic and genetic relationships of bovine noroviruses to human noroviruses and found that they do not share significant antigenic and genetic relationships. Bovine Coronovirus OH compared bovine coronovirus shedding patterns and antibody titers in two groups of calves after shipment to a feedlot and commingled at arrival. Based on the findings, they suggest vaccination of feedlot calves against bovine coronovirus at least 3 weeks prior to shipping to feedlots. KS recommends using the monoclonal (8F2), which has been fully developed and characterized, for immunohistochemical staining of intestinal sections for bovine coronaviruses. Objective 3 Provide training and continuing education opportunities and dissemination of information to students, producers, consumers, veterinarians and diagnostic laboratories: Information on E. coli O157:H7 research, which included the results of clinical trials with the vaccine and direct-fed microbial was disseminated to the public by NE in the form of extension publications; extension meetings with producers, youth groups, and veterinarians; a release to the Associated Press which was covered by 51 newspapers and magazines in the U.S. and Canada; lectures to students in animal science and microbiology classes at UNL (two different courses). Groups in which extension presentations were given included: the Beef Quality Workshop (Mitchell, NE); Nebraska Beef Youth (Lincoln, NE); Northeast Equipment and Farm Show (Madison, NE); Nebraska Veterinary Medical Association (Lincoln, NE); Nebraska Beef Council (Lincoln, NE); and Nebraska Cattlemens Animal Health and Nutrition Committee (Lincoln, NE). The Principle Investigators, Graduate and Post-Graduate Students, and Veterinary Students involved in the MN project have given presentations and updates on ileitis at various scientific, veterinary, and diagnostic meetings in the previous year, including the Conference of Research Workers in Animal Disease, the Leman Swine Conference, the International Pig Veterinary Society and the American Association of Swine Veterinarians. They have disseminated new information, reagents, and procedures to producers, industries, veterinary diagnostic laboratories and veterinarians. In addition, they have presented two international workshops, including theoretical lectures and practical laboratories, on the diagnosis and control of ileitis in pigs.

Publications

Arizona Konkel, M.E. and L.A. Joens: Campylobacter : Molecular and Cellular Biology. Chapter 22. Horizon Press. 2004. Konkel, M.E., Monteville, M.R., Klena, J.D., Joens, L.A.: Microbial Foiod Safety in Animal Agriculture: Current Topics by M.E. Torrence and R.E. Isaacson. Chapter 21, Iowa Atate Press. June, 2003. Lee, M.K., S.J. Billington, L.A. Joens. Potential Virulence and Antimicrobial Resistance in Campylobacter jejuni Isolates Obtained from Food and Companion Animals. In Press. Foodborne Path. Dis. 2004. Raphael, B.H. and L.A. Joens, 2004. Ferrous Iron Uptake is independent of FeoB in Campylobacter jejuni. Can. J. of Micro. In Press. Brands, D.A. A. Inman, C.H. Gerba, J.Mare, S.J. Billington, L.Saif, J.Levine, and L.A. Joens. 2004. The Prevalence of Salmonella spp. In United States oysters. In Press. App. Envir. Micro 2005. Brands, D.A., S.J. Billington, J.F. Levine, and L.A. Joens. Genotypes and antibiotic Resistance of Salmonella Newport Isolates from U.S. Market Oysters. In Press Foodborne Path. Dis. 2005 Illinois J Trask, S. McLaughlin, MS Kuhlenschmidt and P. Kalita 2004 Overland and Near-surface Transport of Cryptosporidium parvum. Environ. Qual. 33:984-983. Johnson, JK, Schmidt, Gelberg, HB, and Kuhlenschmidt MS. 2004. Microbial Adhesion of Cryptosporidium parvum sporozoites: Purification of an Inhibitory Lipid from Bovine Mucosa. J. Parasitology 90:980-990. Kansas Barkey, T.I., Dritz, S.S., Nietfeld, J.C., Johnson, B.J., Minton, J.E. 2004. Effect of dietary nannoligosaccharide and sodium chlorate on the growth performance, acute-phase response, and shedding of weaned pigs challenged with Salmonella enteric serotype Typhimurium. J Anim. Sci. 2004;82:397-404. Minnesota Gebhart, C.J. and R.M.C Guedes. 2004. Lawsonia intracellularis. In C.L. Gyles, et al, (ed.), Pathogenesis of Bacterial Infections in Animals, 3rd ed. Blackwell Publishing, Ames, IA. Walter, D., C.J. Gebhart, J. Kroll, J.T. Holck, and W. Chittick. 2004. Serologic profiling and proper vaccination timing. J. Swine Health Production. (in press). Guedes, R.M.C. and C. J. Gebhart. 2003. Polyclonal and monoclonal antibodies for diagnosis of proliferative enteropathy. J. Vet. Diag. Investi. 15:438-446. Nebraska Berberov, E. M., Y. Zhou, D. H. Francis, M. A. Scott, S. D. Kachman, and R. A. Moxley. 2004. Relative importance of heat-labile enterotoxin in the causation of severe diarrheal disease in the gnotobiotic piglet model by a strain of Escherichia coli that produces multiple enterotoxins. Infect. Immun. 72:3914-3924. Dassanayake, R. P., N. E. Caceres, G. Sarath, and G. E. Duhamel. 2004. Biochemical properties of membrane-associated proteases of Brachyspira pilosicoli isolated from humans with intestinal disorders. J. Med. Microbiol. 53:319-323. Dassanayake, R. P., Y. Zhou, S. Hinkley, C. J. Stryker, G. Plauche, J. T. Borda, K. Sestak, and G. E. Duhamel. Characterization of cytolethal distending toxin of Campylobacter species isolated from captive macaque monkeys. J. Clin. Microbiol., in press. De Cock, H. E. V., S. L. Marks, B. A. Stacy, T. Zabka, J. Burkitt, G. Lu, D. J. Steffen, and G. E. Duhamel. 2004. Ileocolitis associated with Anaerobiospirillum in cats. J. Clin. Microbiol. 42:2752-2758. Folmer, J. D., C. N. Macken, R. A. Moxley, D. R. Smith, S. Hinkley, G. E. Erickson, A. A. Potter, B. B. Finlay, and T. J. Klopfenstein. 2004. Vaccination and direct-fed microbials as intervention strategies for reduction of E. coli O157:H7 in feedlot steers. 2004 Nebraska Beef Cattle Report, University of Nebraska Cooperative Extension MP 80-A, pp. 68-71. Johansson, K. E., G. E. Duhamel, B. Bergsjö, E. O. Engvall, M. Persson, B. Pettersson, and C. Fellström. 2004. Identification of three clusters of canine intestinal spirochaetes by biochemical and 16S rDNA sequence analysis. J. Med. Microbiol. 53:345-350. Moxley, R. A. 2004. Escherichia coli O157:H7: an update on intestinal colonization and virulence mechanisms. Anim. Health Res. Rev. 5:15-33. Potter, A. A., S. Klashinsky, Y. Li, E. Frey, H. Townsend, D. Rogan, G. Erickson, S. Hinkley, T. Klopfenstein, R. A. Moxley, D. R. Smith, and B. B. Finlay. 2004. Decreased shedding of Escherichia coli O157:H7 by cattle following vaccination with type III secreted proteins. Vaccine 22:362-369. Smith, D. R., J. T. Gray, R. A. Moxley, S. M Younts-Dahl, M. P. Blackford, S. Hinkley, L. Hungerford, C. T. Milton, and T. J. Klopfenstein. 2004. A diagnostic strategy to determine the Shiga toxin-producing Escherichia coli status of pens of feedlot cattle. Epidemiol. Infect. 132:297-302. Yang, Z., J. Kovar, J. Kim, J. Nietfeldt, D. R. Smith, R. A. Moxley, M. E. Olson, P. D. Fey, and A. K. Benson. 2004. Identification of common subpopulations of non-sorbitol-fermenting, $-glucuronidase-negative Escherichia coli O157:H7 from bovine production environments and human clinical samples. Applied Environ. Microbiol. 70:6846-6854. Ohio Chang, K.O., S.V. Sosnovtsev, G. Belliot, Y. Kim, L.J. Saif, K.Y. Green. 2004. Bile acids are essential for porcine enteric calicivirus replication in association with down-regulation of signal transducer and activator of transcription 1. Proc Natl Acad Sci USA. Jun 8; 101(23):8733-8. Han, M.G., J.R. Smiley, C. Thomas, L.J. Saif. 2004. Genetic Recombination between Two Genotypes of Genogroup III Bovine Noroviruses (BoNVs) and Capsid Sequence Diversity among BoNVs and Nebraska-Like Bovine Enteric Caliciviruses. J. Clin. Microbiol. 42: 5214-5224. Han, M.G., Q. Wang, J.R. Smiley, K.O. Chang, L.J.Saif. 2004. Self-assembly of the recombinant capsid protein of a bovine norovirus (BoNV) into virus-like particles and evaluation of cross-reactivity of BoNV with human noroviruses. J. Clin. Microbiol. (in press). Saif, L. J. 2004. Bovine Coronavirus Infections. In Infectious Diseases of Livestock, (Coetzer, J.A.W., Thomson, G.R.) Oxford Univ. Press, Oxford, England. Saif, L.J. 2004. Comparative biology of animal coronaviruses: Lessons for SARS. In: SARS The first new plague of the 21st century (M. Peiris, ed), Blackwell Pub., Oxford, UK (in press). Saif, L.J. 2004. Animal Coronaviruses: Lessons for SARS. In: Learning from SARS: Preparing for the next disease outbreak. SARS workshop sponsored by the Institute of Medicine of the National Academy of Sciences, Washington, DC, Sept. 30-Oct. 1, 2003. (in press). Hodgins, D. C., L. Yuan L., V. Parreno, L.B. Corbeil, and L.J. Saif. Mucosal Veterinary Vaccines. In: Mucosal Immunology. Third Edition. Edited by McGhee J. R. Mestecky, J. et al., Academic Press. 2004 (in press). Yuan, L., G. Stevenson and L.J. Saif. Rotavirus and Reovirus. (2004). In: Diseases of Swine. 9th Edition. Edited by Zimmerman, J. J. et al. Ames, Iowa: Iowa State University Press (in press). Saif. L.J. 2004. Animal coronaviruses: what can they teach us about the severe acute respiratory syndrome? Rev. Sci. Tech. Off. Int. Epiz., 23(2): (in press). Saif, L.J. 2004. Animal coronaviruses vaccines: Lessons for SARS. In: Control of Infectious Animal Diseases by Vaccination (Schudel A., M. Lombard, eds). Dev. Biol. Basel, Karger, vol. 119 (in press). South Dakota Berberov, E.M, Y. Zhou, D.H. Francis, M.A. Scott, S.D. Kachman and R.A. Moxley. 2004. Relative importance of heat labile enterotoxin in the causation of severe diarrheal disease in the gnotobiotic piglet model by a strain of enterotoxigenic Escherichia coli that produces multiple enterotoxins. Infect Immun 72: 3914-3924 Washington Bae, W, KN Kaya, DD Hancock, DR Call, YH Park, and TE Besser. Accepted. Prevalence and antimicrobial resistance of thermophilic Campylobacter sp. from cattle farms in the Northwestern United States. Applied and Environmental Microbiology. Borucki, MK, SH Kim, DR Call, S. Smole, and F. Pagotto. Accepted. Discrimination of Listeria monocytogenes epidemic strains using a mixed-genome DNA microarray. Journal of Clinical Microbiology. Cobbold, R. N. and Desmarchelier, P. 2003. In vitro studies on the colonization of bovine colonic mucosa by Shiga-toxigenic Escherichia coli (STEC). Epidemiology and Infection. 132: 87-94. Cobbold, R.N.; Rice, D.H.; Szymanski, M.; Call, D. R.; Hancock, D.D.. 2004. Comparison of Shiga-toxigenic Escherichia coli (STEC) prevalence between dairy, feedlot and cow-calf herds in Washington State. Applied and Environmental Microbiology. 70 (7): 4375-4378. DeFrancesco, K.A.; Cobbold, R.N.; Rice, D.H.; Besser, T.E.; Hancock, D.D.. 2004. Antimicrobial Resistance of Commensal Escherichia coli from Dairy Cattle Associated With Recent Salmonellosis Outbreaks. Veterinary Microbiology. 98 (1): 55-61. González, SF, MJ Krug, ME Nielson, Y. Santos, and DR Call. 2004. Simultaneous detection of marine fish pathogens using multiplexed PCR and DNA microarrays. Journal of Clinical Microbiology 42:1414-1419. Khachatryan, AR, DD Hancock, TE Besser, and DR Call. 2004. The role of calf-adapted Escherichia coli in maintenance of antibiotic resistance in dairy calves. Applied and Environmental Microbiology 70:752-757. Lahmers, S, Y Wu, DR Call, S. Labeit, and H. Granzier. 2004. Developmental control of titin isoform expression and passive stiffness in fetal and neonatal myocardium. Circulation Research 94:505-513. Lane, S., J. Evermann, F. Loge and D.R. Call. 2004. Secondary structure prevents target hybridization to oligonucleotide microarrays. Biosensors and Bioelectronics. ORourke KI, Spraker TR, Hamburg LK, Besser TE, Brayton KA, Knowles DP. 2004. Panicker, G, DR Call, MJ Krug, and AK Bej. Accepted. Detection of pathogenic Vibrio spp. in shellfish and Gulf of Mexico water using multiplex PCR and DNA-array hybridization. Applied and Environmental Microbiology. Straub, TM, Quinoñez Díaz, MD, CO Valdez, DR Call, and DP Chandler. 2004. Using DNA microarrays to detect multiple pathogen threats in water. Water Science and Technology: Water Supply 4:107-114. Warsen, A, MJ Krug, S LaFrentz, DR Stanek, FJ Loge, and DR Call. 2004. Simultaneous discrimination between 15 fish pathogens using 16S rDNA PCR and DNA microarrays. Applied and Environmental Microbiology 70:4216-4221. Willse, A, TM Straub, S. Wunschel, JA Small, DR Call, D Daly, and DP Chandler. 2004. Quantitative oligonucleotide microarray fingerprinting of closely related Salmonella enterica isolates. Nucleic Acid Research 32:1848-1856. Woodford, NL, DR Call, DG Remick, and R Rochford. 2004. A model of angiogenesis in SCID mice xenoengrafted with Epstein-Barr virus transformed B cells. Comparative Medicine 54:209-215.

Impact Statements

Brachyspira - Pathogenesis of Brachyspira pilosicoli, a major cause of colonic spirochetosis, a polymicrobial inflammatory bowel disease that affects humans and a wide range of animal species is being elucidated.
Campylobacter - The discovery of the htrA gene in C. jejuni maybe a key component in future virulence studies. Virulence genes of C. jejuni effect initial and late biofilm development. Results from this study could further future vaccine studies as well as novel approaches for sanitation of farms and food processing plants. The majority of Campylobacter isolates present in poultry appear to be non-pathogenic, as indicated by their inability to survive and/or invade in vitro.
Lawsonia #1 - Information derived from the metabolic reconstruction of Lawsonia may be used to define necessary nutritional components for enhanced cell culture or cell-free growth of the organism. Characterization of the gene products from Lawsonia may assist studies to identify the mechanism that influences the progression of infection and identify proteins for use in serodiagnosis of ileitis.
Lawsonia #2- Specific egg antibodies are capable of controlling the reduction in average daily gain during a Lawsonia infection and are cheaper and less controversial feed additives given the current concerns surrounding feed-grade antibiotics. Analysis of VNTR profiles is method of rapidly detecting Lawsonia and tracing specific isolates may allow rapid identification of the source and transmission pattern of this organism through epidemiological investigations.
Escherichia #1 - The finding that heat-labile enterotoxin may play an important role in colonization is a novel discovery, and provides new foundational knowledge related to the biology and host-pathogen interactions of this important pathogen. Vaccination with type III secreted proteins of enterohemorrhagic E. coli results in a significant reduction in E. coli O157:H7 terminal rectum colonization and detection on rope sampling devices in pens suggests that vaccination should be a useful and eff
Escherichia #2 - Current work represents a rational approach to identification of conditions favorable to development of a disease outbreak. This knowledge could lead to management practices limiting disease susceptibility and/or development of a reproducible model with which to test efficacy of vaccines to be developed in the future. Identification of receptor-binding domains in the major protein subunit of E. coli K88 will enable development of an ETEC subunit vaccine targeted for the product
Porcine Enteric Calicivirus - Since PEC/Cowden causes disease and induces similar intestinal lesions as HuCV infections in humans, it is possible to use PEC/Cowden as a model to investigate the pathogenesis of enteric caliciviruses. Identification of factors in intestinal contents promoting growth of PEC may assist in development of cell culture systems for other fastidious enteric viruses. Characterization of pig sapos and noros will reveal the strains circulating in pigs and their genetic rela
Bovine Enteric Calicivirus - The BEC virus-like particles can be used for serological tests to detect BEC antibodies in cattle and for the identification of serogroups of enteric caliciviruses. Our newly designed primers should provide higher detection rates for BEC in calves including NB-like strains, providing new epidemiological information on their prevalence in cattle. Theses results can be applied for epidemiological surveillance of BEC.
Rotavirus-Group A rotaviruses are among the most important agents associated with severe diarrhea in the young of both animals and people. Since infection of enterocytes is necessarily preceded by attachment of virus to the cell surface, it follows that an understanding of the biology of this interaction is seminal to prophylactic or therapeutic intervention.
Cryptosporidium-Development of assay systems for Cryptosporidium that are biologically relevant and can precisely measure the interactions between the infectious agent and the host cell can help identify and synthesize molecules that are essential for this interaction to occur. Such an approach could benefit not only animal health but would reduce the likelihood of zoonotic spread of C. parvum through contamination of the water supply from domestic livestock operations.

Date of Annual Report: 10/10/2005

Report Information

Annual Meeting Dates: 09/29/2005 - 10/02/2005
Period the Report Covers: 10/01/2004 - 09/01/2005

Participants

NC1007 Members in Attendance: Thomas Besser, Washington State University; Gerald Duhamel, University of Nebraska - Lincoln; Connie Gebhart, University of Minnesota; Richard Isaacson, University of Minnesota; David Francis, South Dakota State University, Lynn Joens, University of Arizona; Rodney Moxley, University of Nebraska Lincoln; Jerome Nietfeld, Kansas State University; Donald Robertson, Kansas State University; Linda Saif, The Ohio State University; and Bert Stromberg (Administrative Advisor for NC1007), University of Minnesota.

Brief Summary of Minutes

The meeting was called to order at 8:10 A.M. by the Chair, Dr. Connie Gebhart.

Linda Saif, with a second by Don Robertson, moved for approval of the 2004 minutes. The minutes were approved by a unanimous vote. Connie Gebhart announced that dues were being accepted by her for all NC1007 members in attendance.

Considerable discussion on the amount of dues followed and is summarized below:
Lynn Joens suggested that dues should be higher to cover the costs of the Gastroenterology awards presented at the CRWAD since the awards are already less that those given by other award committees.

Dave Frances indicated that $50.00 would cover the cost of the meeting room and refreshments.

More discussion followed regarding the lack of attendance by some stations and whether all stations should pay dues if a representative does not attend the meeting.

Richard Isaacson moved that NC1007 should obtain industrial support for the Gastroenterology awards at the CRWAD meeting. In the discussion that followed, it was suggested that we ask for $thousands, and not $hundreds, to support these awards and meetings such as the Rushmore Conference.

Richard Isaacson and Lynn Joens volunteered to draft a white paper that will explain and justify industrial support of awards and meetings sponsored by NC1007 such as the Rushmore Conference. The proposal was adopted with unanimous support.

Lynn Joens then moved to thank Dave Francis for all his hard work and the success of the Rushmore Conference, which was met with enthusiastic approval.

The NC1007 administrative advisor, Bert Stromberg made several comments.
Bert also complemented Dave Francis and all those at South Dakota State University who contributed to the success of the Rushmore conference.

He reported that the project reporting format had changed and SAE form 422 must be filed by him within 90 days after the current meeting. The report should include: 1) accomplishments, and 2) impacts of the work done by members of NC1007. Station reports should be included as an appendix. Publications should be separated into: 1) those from each participating station and 2) publications resulting from collaborative efforts. Dr. Stromberg expressed concern about the low number of publications resulting from collaborative stations in NC1007.

He also informed us that NC1007 will sunset in 2007, if not renewed. A brief letter is needed by the end of 2005 or by the end of February at the latest, 2006, which should include a vision of 3-6 sentences and at least 3 objectives for the future. This information will be distributed to all Experiment Station Directors in an attempt to increase the number of members and station participation in NC1007. The final renewal proposal must be completed by November of 2006.

Richard Isaacson expressed concern that it is difficult to show the impact of the work done by NC1007, which is also supported by Hatch projects that pay salaries of principal investigators. More important, the progress report and impact statements do not indicate the amount of infrastructure that is necessary to do the work.

Since the issue of awards was not resolved before Bert Strombergs comments, discussion continued on the matter.
Lynn Joens raised the issue whether industry should be asked to support travel , banquets and other functions associated with the mission of NC1007. The discussion returned to the nature of the awards presented at the CRWAD meeting. The following issues were resolved:
1. The award will retain the NC1007 name.
2. Industry partners will be recognized in the program at presentation ceremonies.
3. The amount given each year will fluctuate depending on available funds.
4. The awards for graduate students will be included and highlighted in the NC1007 renewal proposal.

The issue not resolved was whether NC1007 should present a Food Safety award at the CRWAD meeting. Since Richard Isaacson is the Food Safety Award committee and Lynn Joens is in charge of the Gastroenterology awards, each will talk with their respective committees and come back with a recommendation at the 2006 meeting on whether NC 1007 should present a Food Safety Award.

Dave Francis moved that Connie Gebhart appoint a committee to write a brief synopsis of the Rushmore conference so that it can be included in the SAE 422 report and in support of a future meeting to be proposed in the renewal. The committee members are Lynn Joens (Chair), Dave Francis, and Richard Isaacson, with input by Roy Curtiss.
Officers for the coming two years were elected by acclamation. Tom Besser will be Chair for the next two years and Don Robertson will serve as Secretary.

Discussion continued on the focus of the NC1007 renewal proposal.

Linda Saif suggested that the focus should be on Common Pathogenic Mechanisms of Zoonotic and Emerging Diseases. This focus could take advantage of much of the expertise in NC1007 on viruses, Camplobacter, Salmonella and diarrheagenic E. coli.

Dave Francis suggested that we should not forget the need for better animal models in the renewal proposal.

Other suggested topics include the importance of the turnover rate of intestinal epithelial cells and the impact on host-parasite relationships.

Discussion continued to return to innate resistance and its impact on changes in virulence due to interspecies transfer coupled with the use of antibiotics in this process.

Richard Isaacson suggested that one objective of the NC1007 renewal proposal should be to organize a colloquium that will identify needs and gaps in studies on Emerging Diseases and Effects of Interspecies Transfer on Virulence based on his positive experience with the Food Safety meeting recently held in Scotland.

Summary of action items from meeting.

1. A summary of the Rushmore conference will be drafted and submitted to a journal such as the Journal of Infectious Disease, which routinely publishes such articles.
2. Richard Isaacson will approach the Academy of Microbiology to determine their level of interest in supporting and organization of a meeting dealing with Common Pathogenic Mechanisms of Zoonotic and Emerging Infectious Diseases including changes of virulence due to interspecies transfer and the importance of innate immunity.
3. Tom Besser will coordinate drafting a vision statement and objectives for the NC1007 renewal and will call a meeting of those committee members present at the 2005 CRWAD meeting in St. Louis.

Tom Besser moved to adjourn the meeting with a second by Don Robertson.

Accomplishments

Accomplishments Objective 1 Define mechanisms of pathogen-host-environmental interactions in enteric and food borne diseases. Campylobacter species AZ has shown that many C. jejuni isolates recovered from non-poultry animal sources have the capacity to cause disease if transmitted to humans. They further assessed the in vitro and in vivo pathogenicity of C. jejuni isolates from broiler chickens and reported the presence of a novel pilus expressed by C. jejuni under biofilm conditions. Clonal strain types of C. coli carrying multiple antimicrobial resistance characterized by PFGE (two enzymes), plasmid profiles and resistance genotyping have been identified as accounting for most of the multiply drug resistant thermophilic Campylobacter sp on WA cattle farms, and related clonal types have been identified on CA cattle farms. Salmonella species AZ reported that an emerging pathogen, S. Newport, has higher survival rates in oysters than E. coli and S. Typhimurium. WA is continuing S. enterica surveillance with collection of isolates from both bovine and human sources from around WA. Antimicrobial resistance profiles are used as a means to putatively match isolates and this latter subset is further evaluated using PFGE. To date numerous matches between strains originating from human and bovine sources have been identified. Lawsonia species MN has demonstrated expression and immunogenicity of ten proteins encoded by the genome of L. intracellularis. Escherichia coli NE is evaluating disruption of enterotoxin genes of enterotoxigenic Escherichia coli by allelic exchange using lambda Red-mediated recombineering. They have optimized the lambda Red recombineering technology for use in ETEC, as demonstrated by the precise disruption of the heat-stable enterotoxin-b (estB) and heat-labile enterotoxin (eltAB) genes, results which encourage further use of this technology in studies aimed at the elucidation of gene function. WA has continued research on the role of the bovine recto-anal junction (RAJ) as a site of colonization for E. coli O157:H7 and how this host-bacterial interaction is involved in the epidemiology of E. coli O157:H7 within cattle populations. Final data analysis confirmed the RAJ colonization and super-shedder findings that were presented in the previous NC-1007 progress report. These were complemented by further analyses including PFGE characterization and comparison studies of isolates. RAJ and fecal isolates matched by animal and date are usually identical or very closely related, suggesting that the RAJ is a significant source of fecal strains. Final data analysis has been performed by WA for another E. coli O157:H7 RAJ project that aimed to examine if bovine immunogenetic parameters were associated with E. coli O157:H7 colonization susceptibility. No associations between the likelihood of an individual heifer to be either E. coli O157:H7-positive or negative and the measured immunological parameters were noted. A project investigating the prevalence and public health risk of non-O157 STEC in foods has been completed. A total of 1440 cattle and 1079 food samples originating from within WA State were examined. From these, a total of 126 bovine and 110 food STEC isolates were characterized, along with 121 regionally and temporally-matched human clinical isolates. A large proportion of bovine-derived food samples had evidence of STEC contamination, based on presence of stx or isolated STEC, indicating a notable likelihood for human exposure, even with post-harvest processing procedures in place. Helicobacter species NE demonstrated that the cytolethal distending toxin B sub-unit of H. hepaticus is a Ca2+- and Mg2+-dependent neutral nuclease. They also showed that it localizes to the nucleus and is the main determinant for intoxication of eukaryotic cells. Enteric Viruses A porcine enteric calicivirus, Cowden strain, can be propagated in a porcine kidney continuous cell line (LLC-PK) in the presence of bile acids in the cell culture medium. OH generated a full-length cDNA infectious clone of this Cowden strain and the capped RNA transcripts derived from this clone were infectious when transfected into LLC-PK cells. The recovered virus retained its ability to infect piglets when administered by the oral route and showed an attenuated phenotype similar to that of the tissue culture-adapted parental virus. To determine the occurrence of human and animal enteric caliciviruses in U.S. market oysters, OH surveyed regional markets. Oysters were collected from different growing areas in the Atlantic and Pacific Oceans and the Gulf coast during summer 2002 and winter of 2002-2003. Animal enteric caliciviruses were detected in 15 samples (33%) by RT-PCR. Bovine noroviruses were detected in 2 samples. Different seasonal and state distributions were detected for human and animal enteric caliciviruses. The presence of animal enteric caliciviruses was associated with states (Oregon, Washington) with major livestock production. Objective 2 Develop and improve diagnostics, treatment, and preventative measures for enteric and food borne diseases. Campylobacter species NE is characterizing a novel Campylobacter cytolethal distending toxin from C. hyointestinalis subsp. hyointestinalis isolated from humans and pigs. Comparative phylogenetic analysis of partial nucleotide and amino acid sequences of cdtB revealed that human and porcine C. hyointestinalis subsp. hyointestinalis formed a cluster distinct from other ECS. Light and confocal laser scanning microscopic examinations of HeLa and INT-407 cells incubated with whole-cell lysates of C. hyointestinalis showed characteristic cytoplasmic and nuclear enlargements indicative of CDT activity. NE, in collaboration with MN, IA, and SC, found that US porcine C. coli isolates are negative for cytolethal distending toxin activity. They examined the reference C. coli strain ATCC 49941 and 40 C. coli strains isolated from pigs on commercial farms in Iowa (n=10), Minnesota (n=10), Nebraska (n=10), and North Carolina (n=9) for the presence of cdtB gene and CDT activity. The cdtB gene was present in all of the strains by PCR amplification of a partial sequence using degenerate and gene-specific oligonucleotide primers. Co-incubation of either HeLa or H407 cells with whole-cell lysates obtained from each strain did not elicit cellular changes characteristic of CDT activity, as determined by either examination using light microscopy or quantitative G2/M phase cell cycle arrest using flow cytometry. Group A Rotavirus IL is investigating receptors as therapeutic approaches to control rotavirus infections. Results suggest that specific oligosaccharide/isoflavone mixtures or profiles may be engineered to provide a deliverable nutriceutical approach to the treatment and prevention of rotavirus disease across susceptible animal species and humans. Cryptosporidium IL has determined the cryptosporidium oocysts are effectively retarded from overland transport by vegetative filter strips (VFS) and that the mechanism of this retardation is specific adhesion to the clay particles of the soil that occurs as a consequence of reduced flow over a vegetated surface as compared to bare soil. Lawsonia species MN evaluated various methods of biochemical augmentation and modification of culture conditions for enhanced growth of L. intracellularis in cell culture. Enhancement of growth in various types of cell cultures (cell types; monolayer and suspension) was evaluated. We also attempted to establish appropriate culture conditions for axenic growth of Lawsonia intracellularis. Despite these efforts, L. intracellularis continues to be an obligate intracellular organism, culturable only in cells in vitro. MN developed an enzyme-linked immunosorbent assay for the diagnosis of proliferative enteropathy in pigs. Analysis of variable number tandem repeat regions (VNTR) in the L. intracellularis genome by MN has provided a means for the differentiation of isolates. This method was demonstrated to be stable, reproducible, and applicable to samples from field outbreaks of proliferative enteropathy. Escherichia coli NE is investigating the role of the Tir protein in Escherichia coli O157:H7 intestinal colonization of adult cattle. Their results suggest that serologically detectable responses to Tir are associated with the level of intestinal infection; however, more studies will be required to determine the relative importance of Tir for E. coli O157:H7 colonization of the adult bovine gastrointestinal tract. NE is evaluating vaccination against type III secreted proteins as a strategy to control Escherichia coli O157:H7 in cattle. In commercially fed cattle, the two-dose vaccine regimen reduced the probability of E. coli O157:H7 colonization of the terminal rectum, and reduced pen-level contamination. Collectively, their clinical trials provide scientific evidence that vaccination with type III secreted proteins is an effective pre-harvest intervention strategy for the control of E. coli O157:H7 in feedlot cattle. Brachyspira species NE is examining B. pilosicoli for the presence of penicillin-binding proteins (PBPs) in comparison with known PBPs of E. coli. Five PBPs of slightly different molecular masses (94-, 62-68-, 42-50-, 25-, and 22-kDa) were identified in a human and two porcine B. pilosicoli strains. Spirochetes that were identified as B. pilosicoli were found by NE to be present in the ceca of 7.5- to 18-week-old commercial turkeys with cecal spirochetosis and typhlitis. Enteric Viruses OH performed a prevalence study of porcine noroviruses and GIII sapoviruses in US swine using newly developed RT-PCR-hybridization assays. The porcine noroviruses were detected exclusively from finisher pigs in 4 of 7 farms and 1 slaughterhouse with an overall prevalence of 20% in finisher pigs. Porcine GIII sapoviruses were detected from all ages of pigs. The prevalence of porcine GIII sapoviruses was 62% overall, lowest in nursing pigs (21%) and highest in post-weaning pigs (83%). Mixed infections of noroviruses and sapoviruses were common in finisher pigs with an overall prevalence of 27% among norovirus- or sapovirus-positive pigs. Two types of BEC have been identified in cattle: the bovine noroviruses (BoNoV) that belong to Genogroup III NoVs and the NB-like BEC more similar to lagoviruses and sapoviruses and which may represent a new calicivirus genus. OH evaluated antibody responses to BoNoV virus-like particles (VLPs) and protection against challenge with virulent homologous BoNoV in gnotobiotic calves. Virus shedding was detected post-challenge on days 1-5 by antigen-capture ELISA. By RT-PCR, virus was detected from all challenged calves for 1-10 days post-challenge. No association between serum and fecal immune responses and protection was observed except in calves immunized intranasally with VLPs in the presence of mLT that had fecal IgA antibodies to BoNoV and showed partial protection to diarrhea after challenge. Bovine coronavirus (BCoV) is a pneumoenteric, cultivable, enveloped, single-stranded RNA virus of positive polarity in the Coronavirus genus within the Coronaviridae family and the Nidovirales order. OH compared the shedding patterns and antibody responses to BCoV in two groups of feedlot calves: those shipped from a single ranch versus those from a sale barn and to evaluate the role of BCoV in disease and on performance. Results suggest that the replication and shedding of BCoV may start in the upper respiratory tract and spread to the gut with viral transmission via the nasal or fecal/oral routes. Vaccination of calves with an effective BCoV vaccine, pre-shipping to feedlots, to induce ELISA serum IgG antibody GMT of >1860, may provide protection against BCoV infection and its combined effects with other pathogens and factors in the induction of respiratory disease. Objective 3 Provide training and continuing education opportunities and dissemination of information to students, producers, consumers, veterinarians and diagnostic laboratories. Minnesota Principle Investigators, Graduate and Post-Graduate Students, and Veterinary Students involved in the project have given presentations and updates on proliferative enteropathy at various scientific, veterinary, and diagnostic meetings in the previous year; including the Conference of Research Workers in Animal Disease, the Leman Swine Conference, ANAPORC (Spain), the Rushmore Conference (sponsored by NC-1007) and the American Association of Swine Veterinarians. They have disseminated new information, reagents, and procedures to producers, industries, veterinary diagnostic laboratories and veterinarians. In addition, they have presented an international workshop, including theoretical lectures and practical laboratories, on the diagnosis and control of proliferative enteropathy in pigs. Nebraska Information on E. coli O157:H7 research, which included the results of clinical trials with the vaccine and direct-fed microbial was disseminated to the public in the form of meetings with producers, veterinarians, and food service industries. Groups in which extension presentations were given included: private meat processing groups, food service industry representatives, the Canadian Cattlemen's Association, Ontario Cattlemens Association, and the National Cattlemens Beef Association. Information on a systems approach to controlling neonatal calf diarrhea was presented in extension programs to cattle producers and veterinarians in Nebraska, South Dakota and Kansas. A lecture was provided on animal production food safety to an undergraduate Foods and Sanitation course. Washington MicroPad, A European FP5 Program, Molecular ecology workshop entitled, Detection of microbial biodiversity in environmental samples, Camerino, Italy, 19-21 September 2005. Call, Assessing intra-specific genetic diversity for bacteria and genetic diversity between plasmids using DNA microarrays. WA-DOE, Colville River TMDL Advisory Group, Colville, WA, 19 July 2005. Call, Microbial source tracking: an update on genetic markers, presentation. U.S. Environmental Protection Agency, Cincinnati, OH, Feasibility of Using DNA/RNA Microarrays and Related Technologies for High Through-put Detection of Waterborne Pathogens, 22-23March 2005. Call, A Primer on Microarrays and the Prospects and Challenges for Pathogen Detection WA State Beef Commission Board Meeting invited speaker. Leavenworth, Washington. 11th August 2004. The role of recto-anal junction E. coli O157:H7 intestinal colonization in influencing feedlot cattle E. coli O157:H7 dynamics. Washington Cattlemans Association General Meeting. Pasco, Washington. 12th November 2004. The Role of Super-shedders in the Epidemiology of E. coli O157:H7 in Feedlot Cattle. Cattle Industry Meeting. San Antonio, Texas. 4th Feb 2005. Dynamics of recto-anal junction colonization and associated fecal shedding of Escherichia coli O157:H7 in feedlot cattle. Beef Industry Safety Summit. Orlando, Florida. 20th April 2005. Dynamics of recto-anal junction colonization and associated fecal shedding of Escherichia coli O157:H7 in feedlot cattle. Pacific Northwest Food Safety Farm to Table Conference 2005. Campylobacter in the Food Supply. Moscow ID. 05/25/05.

Publications

Publications 2005 AZ Thesis & Dissertations Law, B.F. Assessment of the Pathogenicity of Campylobacter jejuni from Broiler Chickens. Doctorial Dissertation, University of Arizona, Tucson, AZ. 2005. Reeser, Ryan. Campylobacter jejuni: Characterization of a microbial Biofilm on Abiotic Surfaces. Masters Thesis, University of Arizona, Tucon, AZ. 2005. Refereed Publications Lee, M.K., S.J. Billington, L.A. Joens. Potential Virulence and Antimicrobial Resistance in Campylobacter jejuni Isolates Obtained from Food and Companion Animals. Foodborne Path. Dis. 1:223-230. 2004. Brands, D.A., A.E. Inman, C.P. Gerba, C.j. Mare, S.J. Billington, L. Saif, J.F. Levine, L.A. Joens. The Prevalence of Salmonella spp. In U.S. oysters. App. Env. Mic. 71:893-897. 2005 Brands, D.A., S.J. Billington, J.F. Levine, L.A. Joens. Genotyping and Resistance Determination of Salmonella Newport Isolates Obtained from U.S. Market Oysters. Foodborne Path. Dis. 2:111-114. 2005. Book Chapters Joens, L.A.: Campylobacter: Molecular and Cellular Biology by M.E. Konkel. Chapter 22, p 415-420. Horizon Press. 2004. IL Kuhlenschmidt MS, Rolsma MD, Kuhlenschmidt T, Gelberg HB. Characterization of a Porcine Enterocyte Receptor for Group A Rotavirus. In: Mechanisms in the Pathogenesis of Enteric Diseases. ed., Paul PS, Francis DH, Benfield DA., pp. 135-143, Plenum Press, New York, N.Y., 1997. MD Rolsma, TB Kuhlenschmidt., HB Gelberg and MS Kuhlenschmidt (1998) Structure and Function of a Porcine Enterocyte Ganglioside Receptor for Group A Rotavirus. Journal of Virology 72:9079-9091. TB Kuhlenschmidt. B Hanafin and MS Kuhlenschmidt (1999) Sialic Acid Dependence and Indpendence of Group A Rotavirus. Adv. In Experimental Biology and Medicine 473:309-317 Gelberg HB, Thulin JD, Kuhlenschmidt MS. Application of Intestinal Xenografts to the Study of Enteropathogenic Infectious Disease. In: Mechanisms in the Pathogenesis of Enteric Diseases. ed., Paul PS, Francis DH, Benfield DA., pp. 31-35, Plenum Press, New York, N.Y., 1997. Rolsma MD, Kuhlenschmidt TK, Gelberg HB, Kuhlenschmidt MS. 1998 Structure and function of a ganglioside receptor for porcine group A rotavirus. J. Virol. 72:9079-9091) Moreno B, Bailey BN, Luo S, Martin MB, Kuhlenschmidt M, Moreno SN, Docampo R, Oldfield E. (2001) (31)P NMR of apicomplexans and the effects of risedronate on Cryptosporidium parvum growth. Biochem Biophys Res Commun. 284:632-637. J Trask, S. McLaughlin, MS Kuhlenschmidt and P. Kalita 2004 Overland and Near-surface Transport of Cryptosporidium parvum. Environ. Qual. 33:984-983. Johnson, JK, Schmidt, Gelberg, HB, and Kuhlenschmidt MS. 2004. Microbial Adhesion of Cryptosporidium parvum sporozoites: Purification of an Inhibitory Lipid from Bovine Mucosa. J. Parasitology 90:980-990. Wetzel DM., Schmidt J, Kuhlenschmidt MS., Dubey JP, and Sibley LD. 2005.Gliding motility leads to active cellular invasion by Cryptosporidium parvum sporozoites. Infection and Immunity 73:5379-5387. Abstracts: Johnson JK, Kuhlenschmidt MS, Gelberg HB. Glycoconjugates and plasma membrane vesicles inhibit Cryptosporidium parvum sporozoite-host cell recognition. Vet Pathol 34:509, 1997. JK Johnson, HB Gelberg, and MS Kuhlenschmidt (1999) - Partial Purification of a Cryptosporidium parvum Sporozoite Host Cell Receptor from Plasma Membrane Vesicles. Second Annual Conference on New and Re-Emerging Infectioius Diseases. JK Johnson, HB Gelberg and MS Kuhlenschmidt (1999) - Partial Purification of a Cell Surface Receptor for Cryptosporidium parvum sporozoite Attachment. Proceedings: American College of Veterinary Pathologists, 50th Annual Meeting, Chicago, IL. MS Kuhlenschmidt, JK Johnson, and HB Gelberg. 1998. Glycoconjugates and Plasma Membrane Vesicles Inhibit Cryptosporidium parvum Sporozoite-Host Cell Recognition. Second International Rushmore Conference on Mechanisms in the Pathogenesis of Enteric Disease. JJ Ward, RD Smith, and MS Kuhlenschmidt (1999) Evaluation of the Premier Cryptosporidium by Meridian Diagnostics for the detection of C. parvum in dairy cattle. Conference for Research Workers in Animal Diseases Proceedings. JJ, Smith RD, and Kuhlenschmidt, MS (1999).Critical control points for reducing environmental contamination with Cryptosporidium parvum oocysts from dairy cattle, Proceedings, 9th Symposium of the International Society for Veterinary Epidemiology and Economics, Aug 6-11, 2000; Breckenridge, CO. JJ Ward, Smith RD, and Kuhlenschmidt, MS. (2000) Simulation model to predict environmental contamination with Cryptosporidium parvum oocysts from a dairy herd,Proceedings, 81st Annual Meeting of the Conference of Research Workers on Animal Diseases (CRWAD). Nov 12-14, 2000; Chicago, IL. Trask, J. R., P. K. Kalita, M. S. Kulhenschmidt, R. D. Smith, and T. L. Funk. 2001. Overland and Near-surface Transport of Cryptosporidium parvum. ASAE Annual International Meeting 01-2104: 1-14. JJ Ward, RD. Smith, MS Kuhlenschmidt. 2002. Evaluation of Factors Contributing to Environmental Contamination with Cryptosporidium parvum from a Dairy Herd. International Conference on Emerging Infectious Diseases, March 2002, Atlanta, Ga. Salto, M.L., Kuhlenschmidt, T., Kuhlenschmidt, M., de Lederkremer, R. M., and Docampo, R. 2004. Lipid composition of acidocalcisomes of Trypanosoma cruzi. 7th Annual Conference on New and Re-Emerging Infectious Diseases. Urbana, April 15-16, p. 23. http://www.cvm.uiuc.edu/idc/ Ochonicky K, Donovan, S, Kuhlenschmidt T. and Kuhlenschmidt M. 2005. Inhibitory effects of human and porcine milk oligosaccharides on sialic acid dependent and sialic acid independent strains of rotavirus. American Dairy Science Association Annual Meeting, Cincinatti, OH, July 24-28, 2005. Ochonicky K, Donovan S. Kuhlenschmidt T, Jimenez-Flores R, Kuhlenschmidt M. 2005. Inhibitory activity of bovine milk fat globule membrane against sialic acid-dependent and independent strains of rotavirus American Dairy Science Association Annual Meeting, Cincinatti, OH, July 24-28, 2005. Andres A., Donovan S.M., Kuhlenschmidt T.B., Kuhlenschmidt M.S. 2005. Isoflavones at concentrations present in soy-based infant formula inhibit rotavirus infectivity in vitro. The FASEB Journal 2005;19: A446. MN Book Chapter S. McOrist and Gebhart, C.J. 2005. Proliferative Enteropathies. In B. Straw, et al, (ed.), Diseases of Swine, Ninth Edition. Blackwell Publishing, Ames, IA. Journal Article Wattanaphansak, S., C.J. Gebhart, M. Olin, and J. Deen. 2005. Measurement of the viability of Lawsonia intracellularis. Can. J. Vet. Res. (in press). Abstracts Beckler, D.C., V. Kapur and C.J. Gebhart. 2004. Molecular epidemiologic typing of Lawsonia intracellularis. Proc. 85th Conf. Res. Workers An. Dis., Chicago, IL, November 14-16. Nuntaprasert, A, K. Kaur, C.J. Gebhart and V. Kapur. 2004. Expression and purification of a flagellar protein of Lawsonia intracellularis. Proc. 85th Conf. Res. Workers An. Dis., Chicago, IL, November 14-16. Wattanaphansak, S. , K. Kinsley, J. Deen and C. Gebhart. 2004. Comparative agreement of indirect fluorescence antibody test and immunoperoxidase monolayer assay for serological diagnosis of field cases of porcine proliferative enteropathy. Proc. 85th Conf. Res. Workers An. Dis., Chicago, IL, November 14-16. Wattanaphansak, S, C. Gebhart, M. Olin, A. Nuntraprasert and J. Deen. 2004. Measurement of the viability of Lawsonia intracellularis. Proc. 85th Conf. Res. Workers An. Dis., Chicago, IL, November 14-16. Beckler, D.C., N.L. Weber and C.J. Gebhart. 2005. Typing of Lawsonia intracellularis isolates by analysis of variable number tandem repeat profiles. Proc. Am. Assoc. Swine Pract., Toronto, Canada Wattanaphansak, S., T. Asawakarn, J. Deen, and C. Gebhart. 2005. Development of an enzyme-linked immunosorbent assay for the diagnosis of porcine proliferative enteropathy. Proc. Allen D. Leman Swine Conf. vol. 32, St. Paul, MN Asawakarn, T., A. Nuntaprasert, K. Kaur, V. Kapur, S. Wattanaphansak, and C. Gebhart. 2005. Expression of recombinant Lawsonia intracellularis proteins. Proc. Allen D. Leman Swine Conf. vol. 32. , St. Paul, MN Wattanaphansak, S., T. Asawakarn, J. Deen, and C. Gebhart. 2005. Development of an enzyme-linked immunosorbent assay for the diagnosis of porcine proliferative enteropathy. Rushmore Conference, Sept. 29-Oct.2, Rapid City, SD Asawakarn, T., A. Nuntaprasert, K. Kaur, V. Kapur, S. Wattanaphansak, and C. Gebhart. 2005. Expression and immunogenicity of proteins encoded by the genome of Lawsonia intracellularis. Rushmore Conference, Sept. 29-Oct.2, Rapid City, SD NE Extension Reports: Peterson, R. E., D. R. Smith, R. A. Moxley, T. J. Klopfenstein, S. Hinkley, and G. E. Erickson. Large-scale clinical trial to evaluate an experimental Escherichia coli vaccine. 2006 Nebraska Beef Report. University of Nebraska Cooperative Extension . Peterson, R. E., D. R. Smith, R. A. Moxley, T. J. Klopfenstein, S. Hinkley, and G. E. Erickson. Vaccination for Escherichia coli O157:H7 in market ready feedlot cattle. 2006 Nebraska Beef Report. University of Nebraska Cooperative Extension. Journal Articles: Carvajal, A., M.L. De Arriba, H. Rodriguez, A.B. Vidal, G.E. Duhamel, and P. Rubio. 2005. Brachyspira hyodysenteriae is relatively more prevalent than B. pilosicoli among commercial pig farms with diarrhoea in Spain. Vet. Rec., in press. Dassanayake, R.P., M.A. Griep, and G.E. Duhamel. 2005. The cytolethal distending toxin B sub-unit of Helicobacter hepaticus is a Ca2+- and Mg2+-dependent neutral nuclease. FEMS Microbiol Lett 251:219-225. Dassanayake, R.P., G. Sarath, and G.E. Duhamel. 2005. Penicillin-binding proteins in the pathogenic intestinal spirochete Brachyspira pilosicoli. Antimicrob. Agents Chemother. 49: 1561-1563. Dassanayake, R.P., Y. Zhou, S. Hinkley, C.J. Stryker, G. Plauche, J.T. Borda, K. Sestak, and G.E. Duhamel. 2005. Characterization of cytolethal distending toxin of Campylobacter species isolated from captive macaque monkeys. J. Clin. Microbiol. 43:641-649. Smith, D. R., R. A. Moxley, S. L. Clowser, J. D. Folmer, S. Hinkley, G. E. Erickson, and T. J. Klopfenstein. 2005. Use of rope-devices to describe and explain the feedlot ecology of Salmonella by time and place. Foodborne Pathog. Dis. 2:61-69. Smith, D. R., R. A. Moxley, S. L. Clowser, J. D. Folmer, S. Hinkley, G. E. Erickson, and T. J. Klopfenstein. 2005. Use of rope-devices to describe and explain the feedlot ecology of Escherichia coli O157:H7 by time and place. Foodborne Pathog. Dis. 2:50-60. Shivaprasad, H.L., and G.E. Duhamel. 2005. Cecal spirochetosis caused by Brachyspira pilosicoli in commercial turkeys. Avian Dis., in press. Book Chapters: Hampson, D.J., and G.E. Duhamel. 2005. Porcine colonic spirochetosis/Intestinal spirochetosis. In: Diseases of Swine. 9th ed. Straw BE, DAllaire S, Mengeling WL, and Taylor DJ (eds). Iowa State University Press, Ames, Iowa, pp. 755-767. Other Presentations and Published Abstracts: Bretschneider, G., E. M. Berberov, and R. A. Moxley. 2005. Role of the Tir protein in Escherichia coli O157:H7 intestinal colonization of adult cattle. Nebraska Symposium on Interdisciplinary Graduate Science Research, University of Nebraska-Lincoln, Lincoln, NE, Sept. 27 (Poster). Bretschneider, G., E. M. Berberov, and R. A. Moxley. 2005. Role of the Tir protein in Escherichia coli O157:H7 intestinal colonization of adult cattle. Third International Rushmore Conference on Enteric Diseases, Rapid City, SD, Sept. 29-Oct. 1 (Poster). Dassanayake, R.P., C.J. Stryker, R.K. Johnson, C.J. Gebhart, K.W. Post, S. Hinkley, W.T. Muraoka, I.V. Wesley, and G.E. Duhamel. 2005. The US porcine Campylobacter coli are negative for cytolethal distending toxin activity. 85th Annual Meeting Conference Research Workers in Animal Diseases, St. Louis, Missouri, November 6-8, (Poster). Dassanayake, R.P., and G.E. Duhamel. 2005. The cytolethal distending toxin B sub-unit of Helicobacter hepaticus localizes to the nucleus and is sufficient for intoxication of eukaryotic cells. 3rd international Rushmore Conference on Enteric Diseases, Rapid City, South Dakota, September 29 - October 1, (Poster). Dassanayake, R.P., C.J. Stryker, R.K. Johnson, W.T. Muraoka, I.V. Wesley, and G.E. Duhamel. 2005. Characterization of a novel Campylobacter cytolethal distending toxin from Campylobacter hyointestinalis subsp. hyointestinalis isolated from humans and pigs. 3rd international Rushmore Conference on Enteric Diseases, Rapid City, South Dakota, September 29 - October 1, (Poster). Dassanayake, R.P., M.A. Griep, and G.E. Duhamel. 2005. The cytolethal distending toxin B subunit of Helicobacter hepaticus is a nuclear localizing Ca2+- and Mg2+-dependent endonuclease. 105th General Meeting of the American Society for Microbiology, Atlanta, Georgia, June 5-9, Abst. B-008, p. (Poster). Duhamel, G.E. 2005. Efficacy of antimicrobial agents for PCS control. Pig Progress, Enteric Diseases Special III., p. 6-8. Duhamel, G.E. 2005. Understanding of colitis in swine improved. Section 4 in Perspectives on Swine Disease Management, Novartis Animal Health, Basel, Switzerland, p. 1-6. Duhamel, G.E. 2005. In vitro and in vivo efficacy of antimicrobial agents for control of porcine colonic spirochaetosis. Section 5 in Perspectives on Swine Disease Management, Novartis Animal Health, Basel, Switzerland, p. 1-6. Erume, J., E. M. Berberov, and R. A. Moxley. 2005. Disruption of enterotoxin genes of enterotoxigenic Escherichia coli by allelic exchange using lambda Red-mediated recombineering. Nebraska Symposium on Interdisciplinary Graduate Science Research, University of Nebraska-Lincoln, Lincoln, NE, Sept. 27 (Oral). Erume, J., E. M. Berberov, and R. A. Moxley. 2005. Disruption of enterotoxin genes of enterotoxigenic Escherichia coli by allelic exchange using lambda Red-mediated recombineering. Third International Rushmore Conference on Enteric Diseases, Rapid City, SD, Sept. 29-Oct. 1 (Poster). Smith DR. 2005. The future of E. coli O157:H7 intervention in live cattle. Cardinal Meats Conference on Food Safety. Toronto, Ontario, Canada. June 24, 2005 (Oral) Smith DR. 2005. Can vaccination reduce the probability that feedlot cattle shed Escherichia coli O157:H7? Invited seminar, University of Guelph, Ontario Veterinary College. Guelph, Ontario, Canada. Apr 29, 2005 (Oral) Smith DR, Moxley RA, Klopfenstein TJ, Peterson RE, Erickson GE. 2005. Population-based strategies for monitoring food safety pathogens in feedlot cattle. Beef Industry Food Safety Council (BIFSCO). Orlando, FL. April 20, 2005. (Oral) Smith DR. 2005. Can vaccination reduce the probability that feedlot cattle shed Escherichia coli O157:H7? Beef Industry Food Safety Summit. Orlando, FL. April 19, 2005. (Oral) Smith DR. 2005. Multidrug-resistant Salmonella: the bovine practitioners role in public health. National Conference on Ground Beef Contaminated with Multidrug-Resistant Salmonella, Including S. Typhimurium DT104: An Emerging Public Health Concern. Tufts University School of Veterinary Medicine, Grafton, MA. March 7-8, 2005. (Oral) Smith DR. 2005. Preventing calf scours with the Sandhills Calving System. Cattlemens Seedstock Showcase. Phillipsburg, KS. Feb 7, 2005. (Oral) Smith DR. 2005. Preventing calf scours with the Sandhills Calving System. UNL Gudmundsen Sandhills Laboratory, Whitman, NE. Jan 4, 2005 (Oral) Smith DR. 2005. Preventing calf scours with the Sandhills Calving System. UNL Extension, Holt County, ONeill, NE. Feb 18, 2005. (Oral) Smith DR. 2005. Preventing calf scours with the Sandhills Calving System. UNL Extension, Brown, Rock, KeyaPaha Counties, Ainsworth, NE. Feb 17, 2005. (Oral) Smith DR. 2005. Preventing calf scours with the Sandhills Calving System. UNL Extension, Custer County. Broken Bow, NE Feb 3, 2005. (Oral) Smith DR. 2005. Preventing calf scours with the Sandhills Calving System. Montrose /Dell Rapids Veterinary Clinic Client Education Meeting, Dell Rapids, SD, Jan 27, 2005. (Oral) OH Book Chapters 1. Saif, L.J. 2005. Comparative biology of animal coronaviruses: Lessons for SARS. In: Severe Acute Respiratory Syndrome. (M. Peiris, et al ed), Blackwell Pub., Oxford, UK, pp. 84-99. 2. Saif, L.J. 2004. Animal Coronaviruses: Lessons for SARS. In: Learning from SARS: Preparing for the next disease outbreak. SARS workshop sponsored by the Institute of Medicine of the National Academy of Sciences, Washington, DC, Sept. 30-Oct. 1, 2003, pp 138-148. 3. Yuan, L., G. Stevenson and L.J. Saif. 2005. Rotavirus and Reovirus. In: Diseases of Swine. 9th Edition. Edited by Zimmerman, J. J. et al. Ames, Iowa: Iowa State University Press (in press). 4. Saif. L.J. and K. Sestak. 2005. TGEV and PRCV. In: Diseases of Swine. 9th Edition. Edited by Zimmerman, J. J. et al. Ames, Iowa: Iowa State University Press (in press). 5. Costantini, V. and L.J. Saif. 2006. Calicivirus and Rotaviruses. In: Fate and transport of zoonotic bacterial, viral and protozoan pathogens during swine manure storage, treatment, and land application, Council for Agricultural Science & Technology, NPB, (submitted). Refereed Journal Articles 1. Chang, K. O., S. S. Sosnovtsev, G. Belliot, Q. Wang, L. J. Saif, and K. Y. Green. 2005. Reverse genetics system for porcine enteric calicivirus, a prototype sapovirus in the Caliciviridae. J Virol 79:1409-16. 2. Wang, Q., M. G. Han, S. Cheetham, M. Souza, J. A. Funk, and L. J. Saif. 2005. Porcine noroviruses: genetic and antigenic relationships to human noroviruses. Emerg Infect Dis.(in press). 3. Wang, Q., M. K. Han, J. A. Funk, G. Bowman, and L. J. Saif. 2005. Genetic diversity and recombination of porcine sapoviruses. J Clin Microbiol. (in press). 4. Wang, Q., K. O. Chang, M. K. Han, S. Sreevatsan, and L. J. Saif. 2005. Development of a new microwell hybridization assay and an internal control RNA for the detection of porcine noroviruses and sapoviruses by reverse transcription-PCR. J Virol Methods. (in press). 5. Han, M.G., S. Cheetham, M. Azevedo, C, Thomas, and L. J. Saif. 2005. Immune responses to bovine norovirus-like particles with various adjuvants and analysis of protection in gnotobiotic calves. Vaccine. (in press). 6. Thomas, C., A. Hoet, S. Sreevatsan, T. Wittum, R. Briggs, G. Duff and L.J. Saif. 2005. Field transmission of bovine coronavirus and herd immunity against associated respiratory disease in feedlot cattle. AJVR (submitted). 7. Costantini, V., F. Loisy, L. Joens, F.S. LeGuyader and L.J. Saif. 2005. Human and animal enteric caliciviruses in oysters from different coastal regions of the U.S. Appl. Envir. Microbiol. (submitted). Abstracts 1. Wang, Q., M. G. Han, S. Cheetham, M. Souza, J. Funk and L. J. Saif. 2005. Detection of porcine noroviruses (PoNoV) from US swine and their genetic and antigenic relationships to human noroviruses (HuNoV). To be presented at the 86th Conference of Research Workers in Animal Diseases, St. Louis, Missouri, December 4-6, 2005. 2. Costantini, V., F. Loisy, J. Joens, F. LeGuyader and L.J. Saif. 2005. Update on calicivirus survey of U.S. market oysters: animal enteric calicivirus. 24th Annual Meeting of the Conference of American Society for Virology, University Park, Pennsylvania, U.S. Abst. #50-10. June 18-22, 2005. Thesis Thomas, C. 2005. Bovine enteric and respiratory viruses: Studies of bovine enteric calicivirus and bovine coronavirus. MS Thesis, The Ohio State University. SD Butler, J. E., D. Francis, J. Freeling, P. Weber, J. Sun, K. L. Nielsen and A. M. Krieg. 2005. Antibody repertoire development in fetal and neonatal piglets. IX. Three PAMPs act synergistically to allow germfree piglets to respond to TI-2 and TD antigens. J. Immunol. 175: 6772-6785. Boots, RE, DH Francis and J. Freeling. Factors Influencing F18+ Escherichia coli Receptor Expression in Weanling Pigs. Abstract. Third International Rushmore Conference on Enteric Diseases. Rapid City, SD. Christie A., V Sebastien, S Gibson, D Francis and V Brozel. 2005. Proteomic analysis of Escherichia coli O157:H7 growing in soil organic matter reveals a unique phenotype. Abstract. Third International Rushmore Conference on Enteric Diseases. Rapid City, SD. Francis D, A Erickson, R Moxley, W Zhang and E Berberov. 2005. Use of germ-free pigs in modeling enterotoxigenic E. coli infections. Invited Presentation. Third International Rushmore Conference on Enteric Diseases. Rapid City, SD. Kaushik R, S George, A Young, and D Francis. 2005. Lectin binding profile of porcine intestinal epithelial cell lines. Abstract. Conference of Research Workers in Animal Diseases, Annual Mtg. St Louis MO. Kaushik RS, S George, A Young, and D Francis. 2005. Lectin binding profile of porcine intestinal epithelial cell lines. Abstract. Third International Rushmore Conference on Enteric Diseases. Rapid City, SD. Koh S, S George, V Brözel, D Francis and R Kaushik. 2005. Porcine Intestinal Epithelial Cell Lines as an in vitro Model for Studying Pathogenesis of Enterotoxigenic Escherichia coli. Abstract. Conference of Research Workers in Animal Diseases, Annual Mtg. St Louis MO. Koh SY, S George, V Brozel, D Francis and RS Kaushik. 2005. Porcine intestinal epithelial cell lines as an in vitro model for studying pathogenesis of enterotoxigenic Escherichia coli. Abstract. Third International Rushmore Conference on Enteric Diseases. Rapid City, SD. Lindblom SJ, SJ Vilain, VS Brozel, RS Kaushik, S George, HH Stein, C Pedersen, D Francis, AJM Rosa. 2005. Characterization of microbial communities in weanling pigs using 16S rRNA gene sequences. Abstract. Third International Rushmore Conference on Enteric Diseases. Rapid City, SD. Zhang W, M Zhao, and D Francis. 2005. Mapping the Binding Domains of K88ac Fimbrial Adhesin. Abstract. Conference of Research Workers in Animal Diseases, Annual Mtg. St Louis MO. WA 1. Bae, W, KN Kaya, DD Hancock, DR Call, YH Park, and TE Besser. 2005. Prevalence and antimicrobial resistance of thermophilic Campylobacter sp. from cattle farms in the Northwestern United States. Applied and Environmental Microbiology 71:169-174. 2. Borucki, MK, J Reynolds, DR Call, T Ward, B Page, and J Kadushin. 2005. Suspension arrays for direct and high throughput subtyping of Listeria monocytogenes from genomic DNA. Journal of Clinical Microbiology 43:3255-3259. 3. Call, DR. 2005. Challenges and opportunities for pathogen detection using DNA microarrays. Critical Reviews in Microbiology 31:91-99. 4. Call, DR, MS Kang, J Daniels, and TE Besser. Accepted. Assessing genetic diversity in plasmids from Escherichia coli and Salmonella enterica using a mixed-plasmid microarray. Journal of Applied Microbiology. 5. Wright JG, Tengelsen LA, Smith KE, Bender JB, Frank RK, Grendon JH, Rice DH, Thiessen AM, Gilbertson CJ, Sivapalasingam S, Barrett TJ, Besser TE, Hancock DD,Angulo FJ. 2005. Multidrug-resistant Salmonella Typhimurium in four animal facilities. Emerg Infect Dis. 11(8):1235-41. 6. Besser TE, LeJeune JT, Rice DH, Berg J, Stilborn RP, Kaya KN, Bae W, Hancock DD. 2005. Increasing prevalence of Campylobacter jejuni in feedlot cattle through the feeding period. Appl. Environ Microbiol. In press. 7. Cobbold, R.N.; Rice, D.H.; Davis, M.A.; Besser, T.E.; Hancock, D.D. Long-term Persistence of Multi-drug resistant (MDR) Salmonella enterica Serovar Newport in Two Washington Dairy Herds. Journal of the American Veterinary Medical Association. In press. 8. Borucki, MK, CC Gay, J Reynolds, KL McElwain, SH Kim, DR Call, DP Knowles. Genetic diversity of Listeria monocytogenes strains from a highly contaminated dairy farm. Applied and Environmental Microbiology. In press.

Impact Statements

NC1007 is defining the mechanisms of pathogen-host-environmental interactions in enteric and food borne diseases.
NC1007 has developed and/or improved diagnostics, treatment, and preventative measures for enteric and food borne diseases.
NC1007 has provided training and continuing education opportunities to students, producers, consumers, veterinarians, and diagnostic laboratories.
NC1007 hosted the Third International Rushmore Conference on Enteric Diseases which sought to integrate the perspectives and knowledge of veterinary and medical scientists in dialogue on the development of strategies for preventing infectious enteric disease and reducing or eliminating dissemination of food-borne pathogens such as Salmonella, E. coli, Campylobacter, Rotavirus and prions. Global impact of enteric disease, animal models, strategies for mucosal immune stimulation, experimental vaccine development, passive immunotherapy and non-immunological methods in disease control were discussed.

Date of Annual Report: 12/27/2006

Report Information

Annual Meeting Dates: 12/02/2006 - 12/03/2006
Period the Report Covers: 10/01/2005 - 09/01/2006

Participants

David Francis, South Dakota State University;
Connie Gebhart, University of Minnesota;
Richard Isaacson, University of Minnesota;
Lynn Joens, University of Arizona;
Radhey Kaushik, South Dakota State University;
Rod Moxley, University of Nebraska;
Donald C. Robertson, Kansas State University;
Bruce Schultz, Kansas State University;
Bert Stromberg, Administrative Advisor for NC-1007;
Mark Robinson, USDA National Program Leader

Brief Summary of Minutes

2006 Meeting of the NC 1007 Regional Research Technical Committee Enteric Diseases of Swine and Cattle: Prevention, Control and Food Safety

Date: December 2 and 3, 2006

Location: Chicago Marriott Downtown Magnificent Mile

NC-1007 Members in Attendance: David Francis, South Dakota State University: Connie Gebhart, University of Minnesota; Richard Isaacson, University of Minnesota; Lynn Joens, University of Arizona, Radhey Kaushik, South Dakota State University; Rod Moxley, University of Nebraska; Donald C. Robertson, Kansas State University; Bruce Schultz, Kansas State University; Bert Stromberg (Administrative Advisor for NC-1007) and Mark Robinson, USDA National Program Leader.

The meeting was called to order at 8:00 A.M. by Dr. Donald Robertson, Secretary of NC-1007, in the absence of the Chair, Dr. Tom Besser

Connie Gebhart, with a second by David Francis, moved for approval of the 2005 minutes.

The NC-1007 Administrative Advisor, Dr. Bert Stromberg, made several comments:
He reminded us that NC-1007 will sunset in 2007 unless the renewal is submitted in a timely fashion and that considerable work on the renewal needs to be done at the meeting.

He expressed concerned at the decline in attendance at NC-1007 meetings and that something should be done to recruit new members. Suggestions by Dr. Stromberg included sponsorship of a one-half day mini-syposium at the CRWAD meeting and encourage attendance by graduate students at both the mini-symposium and the annual meeting of NC-1007.

He reminded the members that meeting minutes should be submitted 30 days after the annual meeting and that the SAE form 422 must be filed by him within 90 days after conclusion of the meeting. The report should include: 1) accomplishments, and 2) impacts of the work done by members of NC -1007. Station reports should be included as an appendix. Publications should be separated into: 1) those from each participating station and 2) publications resulting from collaborative efforts. The limited collaborative efforts of the group is a major concern and should be addressed in the future if NC-1007 is to remain a viable unit.

Since the NC -1007 renewal proposal was the first order of business, there were no formal station reports. Instead, the discussion and efforts were focused on the content and assignment for the renewal proposal. The major sections of the proposal will include:
1. Statement of issues(s) and justification
2. Related, current and previous work
3. Objectives

Discussion of the last two sections was extensive. The following assignments were made after discussion of options and potential collaborations in order to expedite writing of the proposal.

1. Statement of Issue(s) and Justification (T. Besser and D. Robertson)

2. Related, Current, and Previous Work
a. enteric viruses (L. Saif)
b. ETEC and EHEC (D. Francis, R. Moxley, and D. Robertson)
c. Camplobacter spp. and Lawsonia intracellularis (Lynn Joens and C. Gebhart)
d. Salmonella (D. Isaacson and L. Joens)
e. Brachyspira spp. (G. Duhamel)
f. Cryptosporidium parvum and other parasites (M. Kuhlenschmidt and L. Mansfield)

3. Objectives
a. Focus on emerging diseases Identify, characterize, and develop improved detection methods related to newly recognized novel or emerging causes of enteric diseases and enteric pathogens of cattle and swine
1) enteric viruses (L. Saif and Mark Kuhlenschmidt)
2) bacterial diseases
a) changes in disease patterns/trends of recognized pathogens appearance of new/novel virulence factors (D. Francis and L. Joens)
b) EHEC on farm control, transmission, runoff and other environmental issues (T. Besser and T.G. Nagaraja)
c) Salmonella Newport (Tom Besser and Lynn Joens)
b. Focus on effective interventions Develop and improve interventions and preventive measures to reduce the incidence and prevalence of infections of cattle and swine with enteric and food borne disease agents
1) ETEC, EAEC, and EHEC
a) enterotoxins and colonization (D. Francis),
b) effect(s) of multiple enterotoxins on virulence and secretory response (D. Francis, Rod Moxley, D. Robertson and B. Schultz)
c) ETEC vaccines role of LT (D. Francis and L. Joens)
d) EHEC vaccines (R. Moxley)
e) development of probiotics (T.G.Nagaraja)
2) pathogenesis and molecular typing of Lawsonia spp. (C. Gebhart and L. Joens)
3) Campylobacter intervention strategies (T. Besser and L.Joens)
4) Brachyspira spp. (G. Duhamel )
5) viral receptors and intervention ( M. Kuhlenschmidt ??)
6) parasitology ( M. Kuhlenschmidt and L. Mansfield)

c. Focus and dissemination of knowledge Provide training and continuing education opportunities and dissemination of information to student, producers, veterinarians, and diagnostic laboratories (T. Besser, D. Francis, R. Isaacson and Don Robertson)
1) mini-syposium to be held in conjunction with CRWAD
2) 4th International Mount Rushmore conference
3) Focus on Ag - extension related activities
4) Presentation(s) at AAVLD meeting detection of emerging pathogens
5) Colloquium sponsorship by AAM

Richard Isaacson moved to adjourn the meeting with a second by David Francis.

Accomplishments

Publications

A. Journal Articles and other Outputs: jointly authored by multiple NC-1007 stations. Zhang, W., E. M. Berberov, J. Freeling, D. He, R. A. Moxley, and D. H. Francis. 2006. Significance of heat-stable and heat-labile enterotoxins in porcine colibacillosis in an additive model for pathogenicity studies. Infect. Immun. 74:3107-3114. Wang, Q., K. O. Chang, M.G. Han, S. Sreevatsan, and L. J. Saif. 2006. Development of a new microwell hybridization assay and an internal control RNA for the detection of porcine noroviruses and sapoviruses by reverse transcription-PCR. J. Virol. Meth. 132:135-45. Wang, Q.H., M. Souza, J.A. Funk, W. Zhang, and L.J. Saif. 2006. Prevalence of noroviruses and sapoviruses in swine of various ages determined by reverse transcription-PCR and microwell hybridization assays. J. Clin. Microbiol. 44:1575-1578. Costantini, V., F. Loisy, L. Joens, F.S. LeGuyader and L.J. Saif. 2006. Human and animal enteric caliciviruses in oysters from different coastal regions of the U.S. Applied and Environmental Microbiology 72:1800-9. NC Collaborator Joens, AZ B. Journal Articles from NC-1007 stations: Bae W, Hancock DD, Call DR, ParkYH, Berge ACB, Finger RM, Sischo WM, Besser TE. Dissemination of Clonal Strains of Campylobacter coli Resistant to Multiple Antimicrobial Drugs among Washington State and California Cattle. In press, Veterinary Microbiology, 2006. Besser TE, Shaikh N, Holt NJ, Tarr PI, Konkel ME, Malik-Kale P, Whittam T, Bono J.. 2007. Greater Diversity of Shiga toxin-encoding Bacteriophage Insertion Sites among Escherichia coli O157:H7 Isolates from Cattle than from Humans. Appl. Environ. Microbiol. 73:671-9. Bretschneider, G., E. M. Berberov, and R. A. Moxley. Reduced intestinal colonization of adult beef cattle by Escherichia coli O157:H7 tir deletion and nalidixic acid-resistant mutants lacking flagellar expression. Appl. Environ. Microbiol. (Submitted) Call DR, Kang M-S, Daniels J, Besser TE. 2006. Assessing genetic diversity in plasmids from Escherichia coli and Salmonella enterica using a mixed-plasmid microarray. Journal of Applied Microbiology 100(1):15-28. Carvajal, A., M.L. De Arriba, H. Rodriguez, A.B. Vidal, G.E. Duhamel, and P. Rubio. 2006. Prevalence of Brachyspira species in pigs with diarrhoea in Spain. Vet. Rec. 158:700-701. Clark, N. M., E. M. Berberov, M. Wang, and R. A. Moxley. 2006. Anti-capsular antibodies activate killing of Escherichia coli O8:K87 by the alternate complement pathway in porcine serum. Vet. Immunol. Immunopathol. 114:185-191. Cobbold RN, Hancock DD, Rice DH, Berg J, Stilborn R, Hovde CJ, Besser TE. 2007. Recto-anal Junction Colonization of Feedlot Cattle with E. coli O157:H7 and its Association with Super-shedders and Excretion Dynamics. In press. Appl Environ Microbiol. Cobbold RL, Rice DH, Davis MA, Besser TE, Hancock DD: 2006. Long-term persistence of muli-drug resistant (MDR) Salmonella enterica Serovar Newport in two Washington dairy herds. Journal of the American Veterinary Medical Association 228:585-91. Davis MA, Hancock DD, Besser TE, Daniels JB, Kaya K, Call DR. 2007. Antimicrobial resistance in Salmonella enterica serovar Dublin isolates from beef and dairy sources. Vet Microbiol. 31:221-30. Davis MA, Rice DH, Sheng H, Hancock DD, Besser TE, Cobbold R, Hovde CJ: 2006. Comparison of cultures from rectoanal junction mucosal swabs and feces for detection of Escherichia coli O157 in dairy heifers. Applied and Environmental Microbiology 72:3766-70. Deprez, P., K. Chiers, C. J. Gebhart. 2005. Lawsonia intracellularis infection in a 12-month-old colt in Belgium. Vet. Rec. 157:774-776. Han, M.G., S. Cheetham, MS.P. Azevedo, C. Thomas and L. J. Saif. 2006. Immune responses to bovine norovirus-like particles with various adjuvants and analysis of protection in gnotobiotic calves. Vaccine 24:317-26. Han, M.G., D-S. Cheon, X. Zhang and L.J. Saif. 2006. Cross-protection in gnotobiotic calves between a human enteric coronavirus and a virulent bovine enteric coronavirus. J. Virol.80:12350-6. Kang M-S, Besser TE, Call DR. 2006. Diversity of Genetic Contexts of the blaCMY-2 ²-Lactamase Gene in Escherichia coli and Salmonella enterica plasmids that confer resistance to expanded-spectrum cephalosporins. Antimicrobial Agents and Chemotherapy 50):1590-3. Khachatryan AR, Hancock DD, Besser TE, Call DR: 2006. Antimicrobial drug resistance genes do not convey a secondary fitness advantage to calf-adapted Escherichia coli. Applied Environmental Microbiology 72:443-8. LeJeune JT, Hancock DD, Besser TE: 2006. Sensitivity of Esherichia coli O157 detection in bovine feces using broth enrichment followed by immunomagnetic separation and direct plating methodologies. Journal of Clinical Microbiology 44:872-5. Lim JY, Li J, Sheng H, Besser TE, Potter K, Hovde CJ. 2006. Colonization of Escherichia coli O157:H7 at the recto-anal junction of long-duration culture-positive cattle. Appl Environ Microbiol. In press, 2006. McOrist, S., C. J. Gebhart and B. Bosworth. 2006. Evaluation of porcine ileum models of enterocytes infection by Lawsonia intracellularis. Can. J. Vet. Res. 70:155-159. Petersen, R. E., T. J. Klopfenstein, G. E. Erickson, J. Folmer, S. Hinkley, R. A. Moxley, and D. R. Smith. 2007. Effect of Lactobacillus acidophilus strain NP51 on Escherichia coli O157:H7 fecal shedding and finishing performance in beef feedlot cattle. J. Food Prot. 70: (in press). Peterson, R. E., T. J. Klopfenstein, R. A. Moxley, G. E. Erickson, S. Hinkley, G. Bretschneider, E. M. Berberov, D. Rogan, and D. R. Smith. Effect of a type III secreted protein vaccine on Escherichia coli O157:H7 fecal shedding and rectal colonization of feedlot cattle. J. Food Prot. (Submitted) Peterson, R. E., T. J. Klopfenstein, R. A. Moxley, G. E. Erickson, S. Hinkley, D. Rogan, and D. R. Smith. Evaluation of dose response and herd immunity from a vaccine against Escherichia coli O157:H7 for feedlot cattle. J. Food Prot. (Submitted) Wang, Q-H., V. Costantini, and L.J. Saif. 2007. Porcine and human enteric caliciviruses: Comparative diagnosis, epidemiology and genetic and antigenic relatedness. Vaccine (in press). Wattanaphansak, S., C.J. Gebhart, M. Olin and J. Deen. 2005. Measurement of the viability of Lawsonia intracellularis. Can. J. Vet. Res. 69:265-271. Extension Reports: Peterson, R.E., D.R. Smith, R.A. Moxley, T.J. Klopfenstein, S. Hinkley, and G.E. Erickson. 2006. Vaccination for Escherichia coli O157:H7 in market ready feedlot cattle. 2006 Nebraska Beef Report, Agricultural Research Division, University of Nebraska Cooperative Extension, Institute of Agriculture and Natural Resources, University of Nebraska-Lincoln, MP88-A. pp. 68-69. Peterson, R.E., D.R. Smith, R.A. Moxley, T.J. Klopfenstein, S. Hinkley, and G.E. Erickson. 2006. Large-scale clinical trial to evaluate an experimental Escherichia coli O157:H7 vaccine. 2006 Nebraska Beef Report Agricultural Research Division, University of Nebraska Cooperative Extension, Institute of Agriculture and Natural Resources, University of Nebraska-Lincoln, MP88-A. pp. 70-71. Book Chapters: Hampson, D.J. and G.E. Duhamel. 2006. Porcine colonic spirochetosis/Intestinal spirochetosis. In: Diseases of Swine. 9th ed. Straw, B.E., J.J. Zimmerman, S. DAllaire, and D.J. Taylor (eds). Blackwell Publishing Ltd, Ames, Iowa, pp. 755-767. Duhamel, G.E. Neonatal calf enteric disease vaccines. In: Large Animal Internal Medicine. 4th ed., Smith, B.P. (ed). Mosby, Inc., St. Louis, Missouri, in press. McOrist, S. and C.J. Gebhart. 2005. Genus Lawsonia. In G.E. Garrity, et al, (ed.), Bergeys Manual of Systematic Bacteriology, 2nd ed. Williams and Wilkins, Baltimore, MD. McOrist, S. and C.J. Gebhart. 2005. Porcine proliferative enteropathies. In B.E. Straw, et al. (ed), Diseases of Swine, 9th ed. Iowa State University Press, Ames, IA. Other Presentations and Published Abstracts: The effect of regional vaccination within the feedyard on Escherichia coli O157:H7 colonization, fecal shedding, and hide contamination. Smith, D.R., R.A. Moxley, T.J. Klopfenstein, G.E. Erickson. National Cattlemens Beef Association, Beef Industry Safety Summit, Jacksonville, Florida, April 18-20, 2006, Oral. Published - Beef Industry Safety Summit Executive Summary, Beef Industry Food Safety Council, pp. 10-11. Effect of vaccinating against type III secreted proteins of E. coli O157:H7 on its pre- and post-harvest occurrence on cattle hides. Peterson, R.E., D.R. Smith, T.J. Klopfenstein, G.E. Erickson. Joint Meeting of the American Dairy Science Association (ADSA) and American Society of Animal Science (ASAS) Minneapolis, Minnesota, July 9-13, 2006, Oral. Published - abstract no. 269, J. Anim. Sci. Vol. 84, Suppl. 1/J. Dairy Sci. Vol. 89, Suppl. 1, page 250. Effect of vaccination within the feedyard on Escherichia coli O157:H7 colonization, fecal shedding, and hide contamination. Moxley, R.A., D.R. Smith, T.J. Klopfenstein, G.E. Erickson. Cattle Industry Summer Conference, Beef Safety Committee, Reno, Nevada, July 12, 2006, Oral - no publication. Does vaccinating cattle against type III secreted proteins of Escherichia coli O157:H7 prevent colonization? Smith, D.R., R.E. Peterson, R.A. Moxley, T.J. Klopfenstein, G.E. Erickson, S. Hinkley. International Symposium on Veterinary Epidemiology and Economics (ISVEE XI), Cairns, Australia, Aug. 6-11, 2006, Poster - published abstract. Vaccination to control Escherichia coli O157:H7 in feedlot cattle. Moxley, R.A. Invited Seminar Speaker, Department of Veterinary Science and Department of Biology/Microbiology, Molecular and Cellular Biology Seminar Series, South Dakota State University, Brookings, South Dakota. Oct. 13, 2006. Reduced intestinal colonization of adult beef cattle by Escherichia coli O157:H7 tir deletion and nalidixic acid -resistant mutants lacking flagellar expression. Bretschneider, G., E.M. Berberov, R.A. Moxley. 6th International Symposium on Shiga Toxin (Verocytotoxin) Producing E. coli Infections (VTEC 2006), Melbourne, Australia, Oct. 29-Nov. 1, 2006, poster no. P09.1.04 - published abstract. Effect of Lactobacillus acidophilus strain NP51 on Escherichia coli O157:H7 fecal shedding and finishing performance in beef feedlot cattle. Moxley, R.A., D.R. Smith, T.J. Klopfenstein, G.E. Erickson, J.D. Folmer, R.E. Peterson, S. Hinkley. 6th International Symposium on Shiga Toxin (Verocytotoxin) Producing E. coli Infections (VTEC 2006), Melbourne, Australia, Oct. 29-Nov. 1, 2006, poster no. P11.2.05 - published abstract. Effect of a type III secreted protein vaccine on Escherichia coli O157:H7 fecal shedding and rectal colonization of feedlot cattle. Moxley, R.A., D.R. Smith, T.J. Klopfenstein, G.E. Erickson, R.E. Peterson, S. Hinkley, G. Bretschneider, E.M. Berberov, D. Rogan. 6th International Symposium on Shiga Toxin (Verocytotoxin) Producing E. coli Infections (VTEC 2006), Melbourne, Australia, Oct. 29-Nov. 1, 2006, poster no. P11.2.06 - published abstract. A large-scale clinical trial evaluating an Escherichia coli O157:H7 type III secreted protein vaccine for cattle in commercial feedlot systems. Smith, D.R., R.A. Moxley, R.E. Peterson, T.J. Klopfenstein, G.E. Erickson, S. Hinkley, G. Bretschneider, E.M. Berberov. 6th International Symposium on Shiga Toxin (Verocytotoxin) Producing E. coli Infections (VTEC 2006), Melbourne, Australia, Oct. 29-Nov. 1, 2006, poster no. P12.1.04 - published abstract. Effect of dosage number of an Escherichia coli O157:H7 type III secreted protein vaccine on fecal shedding and herd immunity in feedlot cattle. Smith, D.R., R.A. Moxley, R.E. Peterson, T.J. Klopfenstein, G.E. Erickson, S. Hinkley, D. Rogan. 6th International Symposium on Shiga Toxin (Verocytotoxin) Producing E. coli Infections (VTEC 2006), Melbourne, Australia, Oct. 29-Nov. 1, 2006, poster no. P12.1.05 - published abstract. Serological IgG responses against Escherichia coli O157:H7 type III secreted proteins, intimin and O157 lipopolysaccharide in adult beef cattle following experimental infection. Bretschneider, G., E.M. Berberov, R.A. Moxley. Conference of Research Workers in Animal Diseases, Chicago, Illinois, Dec. 3-5, 2006, poster, published - abstract no. P65. Effect of regional vaccination within the feedyard on Escherichia coli O157:H7 rectal colonization, fecal shedding, and hide contamination. Smith, D.R., R.A. Moxley, T.J. Klopfenstein, G.E. Erickson. Conference of Research Workers in Animal Diseases, Chicago, Illinois, Dec. 3-5, 2006, oral, published - abstract no. 110. Wattanaphansak, S.W., T. Asawakarn, C.J.Gebhart and J. Deen. 2006. Development and validation of an ELISA for the diagnosis of PPE. Proc. 19th IPVS, Denmark. Wattanaphansak, S.W., T. Asawakarn, C.J.Gebhart and J. Deen. 2006. Use of the recombinant protein FliC for development of an elisa for the diagnosis of PPE. Proc. 19th IPVS, Denmark. Guedes, R.M.C. and C. Gebhart. 2006. Enterocyte proliferation and apoptotic changes in ileum samples from pigs experimentally infected with Lawsonia intracellularis. Proc. 19th IPVS, Denmark. Gebhart, C. 2006. Lawsonia intracellularis infections (Invited Key Note Lecture). Proc. 19th IPVS, Denmark. Kinsley, K, N. Winkelman, and C. Gebhart. 2006. Elimination of Lawsonia intracellularis from pigs fed carbadox. Proc. Am. Assoc. Swine Vet., Kansas City, MO.

Impact Statements

The effect of regional vaccination within the feedyard on Escherichia coli O157:H7 colonization, fecal shedding, and hide contamination. Smith, D.R., R.A. Moxley, T.J. Klopfenstein, G.E. Erickson. National Cattlemens Beef Association, Beef Industry Safety Summit, Jacksonville, Florida, April 18-20, 2006, Oral.
Effect of vaccinating against type III secreted proteins of E. coli O157:H7 on its pre- and post-harvest occurrence on cattle hides. Peterson, R.E., D.R. Smith, T.J. Klopfenstein, G.E. Erickson. Joint Meeting of the American Dairy Science Association (ADSA) and American Society of Animal Science (ASAS) Minneapolis, Minnesota, July 9-13, 2006, Oral.
Effect of vaccination within the feedyard on Escherichia coli O157:H7 colonization, fecal shedding, and hide contamination. Moxley, R.A., D.R. Smith, T.J. Klopfenstein, G.E. Erickson. Cattle Industry Summer Conference, Beef Safety Committee, Reno, Nevada, July 12, 2006, Oral
Does vaccinating cattle against type III secreted proteins of Escherichia coli O157:H7 prevent colonization? Smith, D.R., R.E. Peterson, R.A. Moxley, T.J. Klopfenstein, G.E. Erickson, S. Hinkley. International Symposium on Veterinary Epidemiology and Economics (ISVEE XI), Cairns, Australia, Aug. 6-11, 2006
Vaccination to control Escherichia coli O157:H7 in feedlot cattle. Moxley, R.A. Invited Seminar Speaker, Department of Veterinary Science and Department of Biology/Microbiology, Molecular and Cellular Biology Seminar Series, South Dakota State University, Brookings, South Dakota. Oct. 13, 2006.
Reduced intestinal colonization of adult beef cattle by Escherichia coli O157:H7 tir deletion and nalidixic acid -resistant mutants lacking flagellar expression. Bretschneider, G., E.M. Berberov, R.A. Moxley. 6th International Symposium on Shiga Toxin (Verocytotoxin) Producing E. coli Infections (VTEC 2006), Melbourne, Australia, Oct. 29-Nov. 1, 2006
Effect of Lactobacillus acidophilus strain NP51 on Escherichia coli O157:H7 fecal shedding and finishing performance in beef feedlot cattle. Moxley, R.A., D.R. Smith, T.J. Klopfenstein, G.E. Erickson, J.D. Folmer, R.E. Peterson, S. Hinkley. 6th International Symposium on Shiga Toxin (Verocytotoxin) Producing E. coli Infections (VTEC 2006), Melbourne, Australia, Oct. 29-Nov. 1, 2006
Effect of a type III secreted protein vaccine on Escherichia coli O157:H7 fecal shedding and rectal colonization of feedlot cattle. Moxley, R.A., D.R. Smith, T.J. Klopfenstein, G.E. Erickson, R.E. Peterson, S. Hinkley, G. Bretschneider, E.M. Berberov, D. Rogan. 6th International Symposium on Shiga Toxin (Verocytotoxin) Producing E. coli Infections (VTEC 2006), Melbourne, Australia, Oct. 29-Nov. 1, 2006
A large-scale clinical trial evaluating an Escherichia coli O157:H7 type III secreted protein vaccine for cattle in commercial feedlot systems. Smith, D.R., R.A. Moxley, R.E. Peterson, T.J. Klopfenstein, G.E. Erickson, S. Hinkley, G. Bretschneider, E.M. Berberov. 6th International Symposium on Shiga Toxin (Verocytotoxin) Producing E. coli Infections (VTEC 2006), Melbourne, Australia, Oct. 29-Nov. 1, 2006
Effect of dosage number of an Escherichia coli O157:H7 type III secreted protein vaccine on fecal shedding and herd immunity in feedlot cattle. Smith, D.R., R.A. Moxley, R.E. Peterson, T.J. Klopfenstein, G.E. Erickson, S. Hinkley, D. Rogan. 6th International Symposium on Shiga Toxin (Verocytotoxin) Producing E. coli Infections (VTEC 2006), Melbourne, Australia, Oct. 29-Nov. 1, 2006
Serological IgG responses against Escherichia coli O157:H7 type III secreted proteins, intimin and O157 lipopolysaccharide in adult beef cattle following experimental infection. Bretschneider, G., E.M. Berberov, R.A. Moxley. Conference of Research Workers in Animal Diseases, Chicago, Illinois, Dec. 3-5, 2006
Effect of regional vaccination within the feedyard on Escherichia coli O157:H7 rectal colonization, fecal shedding, and hide contamination. Smith, D.R., R.A. Moxley, T.J. Klopfenstein, G.E. Erickson. Conference of Research Workers in Animal Diseases, Chicago, Illinois, Dec. 3-5, 2006
Wattanaphansak, S.W., T. Asawakarn, C.J.Gebhart and J. Deen. 2006. Development and validation of an ELISA for the diagnosis of PPE. Proc. 19th IPVS, Denmark.
Wattanaphansak, S.W., T. Asawakarn, C.J.Gebhart and J. Deen. 2006. Use of the recombinant protein FliC for development of an elisa for the diagnosis of PPE. Proc. 19th IPVS, Denmark.
Guedes, R.M.C. and C. Gebhart. 2006. Enterocyte proliferation and apoptotic changes in ileum samples from pigs experimentally infected with Lawsonia intracellularis. Proc. 19th IPVS, Denmark.
Gebhart, C. 2006. Lawsonia intracellularis infections (Invited Key Note Lecture). Proc. 19th IPVS, Denmark.
Kinsley, K, N. Winkelman, and C. Gebhart. 2006. Elimination of Lawsonia intracellularis from pigs fed carbadox. Proc. Am. Assoc. Swine Vet., Kansas City, MO.