Annual/Termination Reports:

[06/29/2005] [01/13/2006] [12/20/2006] [11/28/2007] [01/03/2008] [11/04/2008] [12/01/2009]

Report Information

Participants

Bahr, Janice - University of Illinois - Guest Speaker; Pizzari, Tom - University of Leeds - Guest Speaker; Christensen, Vern (vern_christensen@ncsu.edu) - North Carolina State University; Froman, David (david.froman@oregonstate.edu) - Oregon State; Grizzle, Judy (jgrizzle@utk.edu) - University of Tennessee; El Halawani, Mohamed (elhal001@umn.edu) - University of Minnesota; Johnson, Paul; Kirby, John (jkirby@uark.edu) - University of Arkansas; Long, Julie - USDA ARS; Millam, Jim (jrmillam@ucdavis.edu) - University of California - Davis; Mirando, Mark - CSREES; Proudman, John (johnp@anri.barc.usda.gov) - Biotechnology and Germplasm Lab; Rhoads, Doug (drrhoads@uark.edu) - University of Arkansas; Satterlee, Dan (dsatterlee@agcenter.lsu.edu) - Louisiana State University; Siopes, Tom (tom_siopes@ncsu.edu) - North Carolina State University; Wilson, Jeanna (jeannaw@uga.edu) - University of Georgia

Brief Summary of Minutes

The meeting was held at the Heathman Lodge in Vancouver, Washington on October 21 and 22, 2004.

October 21:

Female control of fertility in the domestic fowl. Tom Pizzari, University of Leeds (Guest Speaker)

Avian infectious bronchitis virus and male fertility. Janice Bahr, University of Illinois (Guest Speaker)

Is chicken FSH secretion regulated by GnRH? John Kirby, University of Arkansas

Genetic analysis of sperm dysfunction degeneration (SDD) in broiler breeders. Doug Rhoads, University of Arkansas

Deduction of a model for sperm storage in the hen's oviduct. David Froman, Oregon State University

Lectin characterization of surface carbohydrates in poultry spermatozoa. Julie Long, USDA, ARS, Beltsville

Embryo growth may affect metabolic health of turkeys. Vern Christensen, NCSU

When does programming for photorefractoriness occur in the turkey hen? John Proudman, USDA, ARS, Beltsville

Alterations in ovarian folliculogenesis in broiler breeder hens actively immunized against chicken inhibin. Dan Satterlee, LSU

October 22:

Station Report, Tom Siopes, NCSU

Station Report, Jim Milam, UC Davis

Station Report, Mohamed El Halawani, University of Minnesota

Administrative update, Mark Mirando, CSREES

Business meeting, D. P. Froman, Chair

1) An announcement was made that station reports were to be filed within 60 d of the meeting.

2) Due to a catastrophic hard disk failure, the proposal must be reconstructed. This effort was to be performed by D. P. Froman with detailed input from members. Input was requested by November 30th. Proposal reconstruction would begin in December 2005.

3) The proposed site for the 2005 meeting was Las Vegas, Nevada. Tentative meeting dates were identified: October 27 and 28 or November 3 and 4. Jim Milam agreed to host the meeting.

Accomplishments

DC305 was formed for the purpose of transitioning between S-285 Reproductive Efficiency of Turkeys into a regional project that addressed reproductive efficiency of poultry in general. This goal was realized as evidenced by retention of core scientists who participated in the prior project and the addition of new scientists whose specialties enhance the expertise of the group. As such, the group of scientists within the new project have the capability of addressing the range of problems encountered in commercial poultry reproduction, which includes laying hens and broiler breeders in addition to turkeys. While fundamental expertise was retained with respect to the study of photorefractoriness and broodiness in turkeys, significant expertise has been added with respect to broiler breeders. This is noteworthy due to the per capita consumption of broiler meat within the U.S.

Publications

None as the objectives of DC305 was the development of a new multistate project as opposed to the completion of experimental objectives as evidenced by peer-reviewed journal articles.

Impact Statements

1. The intended outcome of DC305 is the preparation of a new regional project to be completed in early 2005. The potential impact of this effort will be the formal alignment of the foremost U.S. scientists who study poultry reproduction, a biological process that underlies a multi-billion dollar industry within the U.S.

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Report Information

Participants

Bahr, Janice (jbahr@uiuc.edu) - University of Illinois; Cherry, Jerry (agresch@uga.edu) - The University of Georgia; El-Halawani, Mohamed (elhal001@umn.edu) - University of Minnesota; Estevez, Inma (iestevez@umd.edu) - University of Maryland; Froman, David (David.Froman@oregonstate.edu) - Oregon State University; Johnston, Paul(paul_johnston@byu.edu) - Brigham Young University; Kirby, John (jkirby@uark.edu) - University of Arkansas; Kuenzel, Wayne (wkuenzel@uark.edu) - University of Arkansas; Millam, Jim (jrmillam@ucdavis.edu) - UC Davis; Mirando, Mark (mmirando@csrees.usda,gov) - CSREES, USDA; Proudman, John (johnp@anri.barc.usda.gov) - ARS Beltsville, MD;
Ramachandran, Ramesh (RameshR@psu.edu) - The Pennsylvania State University;
Rhoads, Doug (drhoads@uark.edu) - University of Arkansas; Satterlee, Dan (dsatterlee@agctr.lsu.edu) - Louisiana State University; Siopes, Tom (tom_siopes@ncsu.edu) - North Carolina State University; Wilson, Jeanna (jeannaw@uga.edu) - The University of Georgia

Brief Summary of Minutes

The business meeting with an industry perspective provided by Don McIntyre (Hybrid Turkeys). Whereas increasing industry attendance and participation was acknowledged as a group goal, there is value in keeping the number of participants relatively small in order to foster participant interaction. Favorable remarks were made about the format and the value of maintaining an ordered, and yet informal meeting. Participants were encouraged to apply for grant applications through the USPEA.

The remainder of the business meeting was chaired by David Froman. In spite of project approval, there were two outstanding issues that needed resolution. The first was addressing how S1020 meets national research priorities. This question was answered, in part, by the fact that many participants have active grants from the NRICGP, which by definition, defines national research priorities affecting agriculture. Another consideration was the fact that the S1020 group includes a majority of US scientists who conduct research with turkeys. The second issue pertained to integration of extension. Perhaps a broader goal would be commercial application rather than extension activities per se; for a number of S1020 hold US patents and have, to some extent, been involved with technology transfer. However, it must be remembered that the application of any technology is often constrained by regulatory, legal, or commercial interests beyond the control of either scientists or extension specialist.

Dr. Cherry agreed to facilitate any outstanding editing of the project related to these issues.

Clarification was sought pertaining to filing station reports. Each member who participates as a leader of an Agricultural Experiment Station project needs to file an AD-421 form through his or her Experiment Station. This effort eventually entails filing an individual termination report. Nonetheless, annual and termination reports must also be filed for the group. David Froman agreed to collect input from participants and then edit input for submission to NIMSS.

The site for the 2006 annual meeting was discussed. Annual meetings were held on the West Coast for 2004 (Portland, OR) and 2005 (San Francisco, CA). Therefore, it was proposed to hold the next meeting in the East. Potential sites included coastal Georgia, Puerto Rico, or the US Virgin Islands. Doug Rhoads agreed to investigate Caribbean options. Should these prove to be too expensive, Jeanna Wilson agreed to investigate sites on the Georgia coast. A location was to be defined early in 2006 for the purpose of advance planning, in particular, inviting key R&D VPs or their representatives.

David Froman volunteered to serve as Project Chair for 2006 in order to expedite and complete the transition from S285 to S1020. This proposal was so moved, seconded, and approved by acclimation.

The meeting adjourned with a thanks to Jim Millam for organizing and hosting the meeting. Positive remarks were also made by Mark Mirando and Jerry Cherry about the quality of the meeting and the accomplishments of the group.

Accomplishments

Countering a long-term decline in the fertility of meat-type chickens.<br /> <br /> This effort addressed two broad factors affecting reproductive success: gamete quality and behavior. In turn, the investigation of each factor warranted diverse experimental approaches. In the case of gamete quality, these included the search for: (1) a gene that compromises sperm viability prior to ejaculation (Arkansas and Oregon); (2) a vaccine against avian infectious bronchitis virus that does not compromise epididymal function (Illinois and Arkansas); and (3) the basis for phenotypic variation in sperm mobility, a primary determinant of male fertility (Oregon and Arkansas). <br /> <br /> Doug Rhoads led the effort directed at finding the gene that induces a condition in which males ejaculate large percentages of dead sperm. This condition is called sperm degeneration dysfunction (SDD) because premature sperm degeneration appears to be due to a dysfunction of the male reproductive tract. Whereas this problem was attributed to a single dominant gene after the completion of breeding experiments in the late 20th century, this gene has proven difficult to find. Pedigreed populations of chickens have been produced using replicate affected broiler breeder males as founding sires. Birds from these populations were used to map the trait to a 3 Mbp region of chromosome 7 in one family. The same trait was mapped to chromosome 1 in a different family. Future work will be aimed at refining the map and developing a genetic test for SDD, i.e. a test based upon DNA rather than sperm cell viability. <br /> <br /> Janice Bahr led the investigation of the interaction between vaccination against avian infectious bronchitis virus (AIBV) and epididymal function. Chickens are routinely vaccinated against AIBV to prevent disease. Unfortunately, one unwanted side effect in males is compromised epididymal function. Specifically, stones form within the excurrent ducts of the testis. This phenomenon is analogous to kidney stones within the urinary tract. Roosters were immunized with a killed virus in order to determine whether stone formation was dependent upon live virus particles entering and then replicating within ciliated epithelial cells (the type of cell this virus attacks regardless of location). However, time course of stone development was comparable to that of controls vaccinated with live, attenuated AIBV. Thus, an autoimmune condition may result in which anti-AIBV antibodies, sperm agglutination, and stone formation are related. In any event, immunization of commercial flocks with killed AIBV is not a solution. Whereas killed AIBV does induce a stong immune response, the deleterious side effect persists.<br /> <br /> David Froman led the investigation of mechanisms underlying phenotypic variation in sperm mobility. Previous work had established that mitochondrial function was pivotal to phenotypic expression. Thus, experiments were designed to identify the reason for compromised mitochondrial function in low mobility sperm, i.e. sperm that are viable  perhaps even motile  but nonetheless lack an ability to move against resistance at body temperature. A model was proposed that accounts for the phenotypic range observed in broiler breeders. Seminal plasma glutamate enabled calcium uptake via NMDA receptors prior to ejaculation. Excessive calcium uptake triggers formation of the mitochondrial permeability transition pore, a prelude to mitochondrial demise. Sperm mobility is lost in proportion to the size of the subpopulation in which the mitochondrial permeability transition pore has formed.<br /> <br /> The importance of sperm mobility to broiler breeder performance was corroborated by a comparative assessment of males within two modern meat strains and the Athens random bred meat strain (Georgia and Oregon State). This effort was led by Jeanna Wilson. It is noteworthy that the Athens random bred males approximate founder stock from the 1950s. As evidenced by the magnitude of sperm mobility measurements and proportions of males within strains characterized by poor sperm mobility, it appears that sperm mobility has been compromised as broiler breeders have been selected for fast, efficient growth. <br /> <br /> In summary, advances were made relative to genetic and environmental factors that affect sperm quality. Likewise, advances were made in understanding how behavior affects broiler breeder reproductive efficiency (Maryland and USDA Beltsville). This effort was led by Inma Estevez. Specifically, reduced male mating frequency was not a cause of reduced fertility, although as expected, mating frequency depended upon the level of male-male competition within the mating system and was plastically adjusted accordingly. Variation in sperm quality did not appear to be a significant factor. The reasons why high mating frequency and sperm quality were poor predictors of fertility remain unresolved. Nonetheless, results strongly support the hypothesis that low male reproductive success may be related to poor male mating efficiency. Thus, there is a distinction between attempted copulation (mating frequency) and successful copulation (mating effectiveness).<br /> <br /> Developing an adaptive, comprehensive understanding of turkey egg hatchability that can be applied by commercial hatcheries.<br /> <br /> Due to large number of eggs that pass through hatcheries, correlation studies are highly suited to elucidating key variables that affect embryonic development and successful hatching. Likewise, the properties of the eggshell itself afford limitations and therefore insight into how eggs should be handled. For example, transport of gases, e.g. oxygen, through the eggshell is affected by egg weight, eggshell conductance, and the duration of embryonic development. Theoretically, embryo livability can be improved by changing egg weight, the properties of the eggshell, or incubation period. Of these three variables, only incubation period can be controlled by an operator. And complications arise because functional egg characteristics vary among lines of turkey hens and between hens at different ages within a line under any given set of conditions. Nonetheless, an advance was made by proving embryonic cardiac function to be a critical and useful variable for correlation analyses. This effort was led by Vern Christensen (NCSU) working in conjunction with Paul Johnston (BYU).<br /> <br /> Discovering the basis for photorefractoriness in turkeys.<br /> <br /> This effort was performed by Jim Millam (UC Davis), John Proudman (ARS, Beltsville) and Tom Siopes (NCSU). Understanding the neuronal circuitry controlling photorefractoriness is important in developing means to reduce photorefractoriness. Research at UC Davis advanced the understanding of neural control of photorefractoriness by narrowing the possibilities as to where a photorefractory block occurs within the brain. Research at Beltsville tested the efficacy of lighting programs aimed at retarding the onset of photorefractoriness. Manipulation of the photoperiod to prolong egg production must be done prior to 8 weeks after photostimulation (increased daylength). Ironically, daylength programs the brain to begin and end reproduction. The programming that serves to end reproduction appears to occur between 9 and 12 weeks after photostimulation. Therefore, timely reduction in photoperiod may prolong lay. Research at NCSU assessed the potential of light intensity as a management tool for controlling photorefractoriness. The threshold light intensity for photorefractoriness seems to be higher than that for photoperiodic drive. Collectively, these results suggest that modulation of timing and intensity may serve to affect the brain in a desirable manner.<br /> <br /> Explaining the CNS integration that drives the hypothalamic-pituitary-gonadal axis.<br /> <br /> Avian reproduction is entrained by photoperiod. In other words, encephalic photoreceptors ultimately affect the secretion of gonadotropin releasing hormone (GnRH). Consequently, the location and structure of neuronal networks are critical pieces of information relative how reproduction is controlled by the brain (Arkansas, Minnesota, UC Davis) In addition, the flow of information within the hypothalamic-pituitary-gonadal axis is another key area of study. This includes gene transcription in addition to the interaction of either neurotransmitters or hormones and their receptors (Arkansas, Louisiana State, Penn State).<br /> <br /> Wayne Kuenzel led an effort related to encephalic photoreception. When electrolytic lesions were made in the circumventricular organ, the development of the reproductive system was attenuated relative to intact controls. This region of the forebrain is known to contain photoreceptors. Thus, greater definition was given to the region of the brain that initiates and regulates the effect of photoperiodicity in birds. Likewise, a study was completed in which GnRH neurons were mapped and counted. Seven nuclei were observed within the forebrain and diencephalon that contain these crucial neurons. In addition, six terminal fields were identified. A second accomplishment was demonstrating a cost effective means of inducing molt that does not compromise animal welfare.<br /> <br /> In addition to neurons that secrete GnRH, the CNS contains neurons that secrete gonadotropin-inhibiting hormone. Ramesh Ramachandran discovered that neurons containing GnIH are located exclusively in hypothalamic paraventricular nuclei. The density of these neurons was comparable between egg-type chickens that were either in or out of lay. However, real-time quantitative PCR revealed a significant increase in GnIH mRNA in the diencephalons when hens were out of lay. In related work, GnIH depressed LH secretion from pituitary cells cultured in vitro. Finally, cDNA encoding the chicken GnIH receptor was cloned from a chicken pituitary cDNA library. Sexually immature egg-type chickens were found to have more GnIH receptor mRNA in their pituitary glands when compared to laying hens.<br /> <br /> FSH, like LH, is a pituitary hormone that affects gonadal function. However, the role of FSH is less understood. John Kirbys lab advanced FSH biology by cloning and expressing of the FSH beta proximal promoter from the domestic fowl. Computer-based analysis of bases within this region revealed in excess of 50 common DNA binding motifs. Sequential deletion mutants were intiated for further characterization.<br /> <br /> Regulation of the hypothalamic-pituitary-gonadal axis historically has been viewed in terms of environmental factors or chemical agents (exogenous or endogenous) acting upon an individual animal. However, Dan Satterlee demonstrated that the hypothalamic-pituitary adrenal axis of a dam can affect the hypothalamic-pituitary-gonadal axis of her male offspring. The agent that passes from dam to offspring is the steroid hormone corticosterone. Lines of Japanese quail have been selected for either low stress (LS) or high stress (HS). Reproductive traits were evaluated for male offspring from control or corticosterone-treated hens in each line. Cloacal foam production is a classic secondary sexual characteristic that is androgen dependent. Foam production at 8 weeks of age was staggered as follows: LS control > LS corticosterone > HS control > HS corticosterone. Consequently, genetic selection and maternal corticosterone appear to affect the hypothalamic-pituitary-gonadal of progeny.

Publications

Bilcik, B., and I. Estévez. 2005. Impact of male-male competition and morphological traits on mating strategies and reproductive success in broiler breeders. Appl. Anim. Behav. Sci. 92:307-323.<br /> <br /> Bilcik, B., I. Estévez, and E. Russek-Cohen. 2005. Reproductive success of broiler breeders in natural mating systems: The effect of male-male competition, sperm quality, and morphological characteristics. Poult. Sci. 84:1453-1462. <br /> <br /> Froman, D. P., and A. J. Feltmann. 2005. Fowl (Gallus domesticus) sperm motility depends upon mitochondrial calcium cycling driven by extracellular sodium. Biol. Reprod. 72:97-101<br /> <br /> Froman, D. P., and J. D. Kirby. 2005. Sperm mobility: Phenotype in roosters (Gallus domesticus) determined by mitochondrial function. Biol. Reprod. 72:562-567.<br /> <br /> Kang, S.W., A. Thayananuphat, I. Rozenboim, J. R. Millam, J. A. Proudman and M. E. El Halawani. 2005. Expression of hypothalamic GnRH-I mRNA in the female turkey at different reproductive states and following photostimulation. General and Comparative Endocrinology (In press.)<br /> <br /> Proudman, J. A., and T. Siopes. 2005. Thyroid hormone and prolactin profiles in male and female turkeys following photostimulation. Poult. Sci. 84:942-946.<br /> <br /> Rathiam, T., and W. J. Kuenzel. 2005. Attenuation of gonadal response to photostimulation following ablation of neurons in the lateral septal organ of chicks. Brain Res. Bull. 64:455-461.<br /> <br /> Scanes, G. G., S. Jeftinija, A. Glavaski-Joksimovic, J. A. Proudman, and C. Aramburo. 2005. The anterior pituitary gland: Lessons from livestock. Domestic Anim. Endocrinol. 29:23-33.<br /> <br /> Siopes, T. 2005 Spontaneous recovery of photosensitivity by turkey breeder hens given prolonged exposure to long day lengths. Poult. Sci. 84:1470-1476.<br /> <br /> Wilhelms, K. W., S. A. Cutter, J. A. Proudman, L. L. Anderson, and C. G. Scanes. Atrazine and the hypothalamo-pituitary-gonadal axis in sexually maturing precocial birds: Studies in male Japanese quail. Toxicological Sci. 86:152-160.

Impact Statements

1. There exists a dogma that selection for growth necessarily compromises reproduction. However, this has yet to be demonstrated by genomics The reproductive traits under investigation, be they the behavior of a sperm cell or a bird, will serve to help interpret the chickens genome. Therefore, detailed characterization of broiler breeder reproduction, in conjunction with the chicken genome, will provide primary breeders with new insights applicable to sustainable breeding practices.
2. Commercial turkey production is depends on artificial incubation. However, efficacy is determined by the conditions under which eggs are incubated as well as the nature of the egg itself. This latter fact complicates the attempt to maximize hatchability because egg properties are subject to genetic selection and vary amongst commercial stock. Therefore, characterizing the interaction between incubators and eggs will provide adaptable schemes for technical advances.
3. Photorefractoriness is the single largest biologic impediment limiting production of turkey hatching eggs. Discovering how environmental light fits into a temporal scheme that affects the hypothalamo-pituitary-gonadal axis will define new management schemes applicable to the induction and the maintenance of lay in turkey hens.
4. Whereas the hypothalamo-pituitary-gonadal axis controls reproduction, neurosecretion from hypothalamic neurons is controlled by neurons elsewhere within the brain and these neurons, in turn, are affected by environmental stimuli. Thus, describing how reproduction is controlled by the central nervous system will identify precise control points for environmental variables used to managed reproduction in poultry.

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Report Information

Participants

Brief Summary of Minutes

2006 Business Meeting

Report Information:
· Annual Meeting Dates: 10/26/06 and 10/27/06
· Period the Report Covers: 01/2006 to 12/2006

Participants:

· Wallace, Berry (berrywd@auburn.edu)  Auburn University
· El-Halawani, Mohamed (elhal001@umn.edu)  University of Minnesota
· Froman, David (David.Froman@oregonstate.edu)  Oregon State University
· Grizzle, Judy (jgrizzle@utk.edu)  University of Tennesee
· Hagler, Winston (winston_hagler@ncsu.edu)  North Carolina State University
· Jurkevich, Alexander (ajurkev@uark.edu)
· Kuenzel, Wayne (wkuenzel@uark.edu)  University of Arkansas
· Millam, Jim (jrmillam@ucdavis.edu)  UC Davis
· Mirando, Mark (mmirando@csrees.usda.gov)  CSREES, USDA
· Proudman, John (miles-to-go@prodigy.net)  ARS Beltsville, MD (retired)
· Rhoads, Doug (drhoads@uark.edu)  University of Arkansas
· Satterlee, Dan (dsatterlee@agctr.lsu.edu)  Louisiana State University
· Siopes, Tom (tom_siopes@ncsu)  North Carolina State University
· Wood, Ben (ben.wood@hybridturkeys.com)  Hybrid Turkeys

Brief Summary of Minutes of Annual Meeting:

The business meeting was chaired by David Froman using the following outline: (1) a thanks to Doug Rhoads, (2) future leadership, (3) participation in annual meetings, (4) meeting organization, (5) annual reports, and (6) the 2007 annual meeting. Doug Rhoads was thanked for his organizing the 2006 annual meeting in St. Croix, US Virgin Islands. The quality of accommodations and the meetings structure were enjoyed by all. With respect to group leadership, D. P. Froman agreed to continue as chair. Meeting organization has assumed to forms to date. Whereas the traditional approach has been to share research results by experiment station or experimental objectives, a topical approach also has been used. In view of the groups goal for increased industry participation (preferably VPs of research and development or their representatives), an argument was made in favor of a topical approach; for this affords industry personnel an overview of subjects to be discussed well in advance of the annual meeting. Thus, a compromise approach is to organize presentations by topic within project objectives as was done during the 2006 annual meeting.

With respect to the S1020 annual report, members were reminded that a single report is to be submitted to NIMSS from the group through the chair to Dr. Hagler. This report entails a synthesis of accomplishments. Thus, members were encouraged to first read the 2005 annual report on-line at NIMSS and then write their contributions with an emphasis on integration as well as the advancement of the projects goals. Only pertinent publications were to be included. Data summaries such as graphs and tables are not acceptable for preparation of the annual report. It is the responsibility of each member to succinctly summarize accomplishments using language that can be understood by a wide audience.

The advantages and disadvantages of several potential meeting sites were discussed. However, a consensus arose with respect to coastal Georgia as a first choice. Thus, the chair agreed to contact Dr. Jeanna Wilson upon his return to work. Tentative meeting dates were either the 25th and 26th of October or the 1st and 2nd of November, 2007.

Both Dr. Hagler and Dr. Mirando deemed the level of participation to be acceptable even though a number of participants were unable to attend the annual meeting. This concerned the chair in that the primary objective of the project is collaboration. In view of the distribution of participants throughout the US, the annual meeting may be the only time some participants see each other during the course of a year.

Accomplishments

<br /> <br /> Report Information:<br /> · Annual Meeting Dates: 10/26/06 and 10/27/06<br /> · Period the Report Covers: 10/2005 to 10/2006<br /> <br /> Participants:<br /> <br /> · Wallace, Berry (berrywd@auburn.edu)  Auburn University<br /> · El-Halawani, Mohamed (elhal001@umn.edu)  University of Minnesota<br /> · Froman, David (David.Froman@oregonstate.edu)  Oregon State University<br /> · Grizzle, Judy (jgrizzle@utk.edu)  University of Tennesee<br /> · Hagler, Winston (winston_hagler@ncsu.edu)  North Carolina State University<br /> · Jurkevich, Alexander (ajurkev@uark.edu)<br /> · Kuenzel, Wayne (wkuenzel@uark.edu)  University of Arkansas<br /> · Millam, Jim (jrmillam@ucdavis.edu)  UC Davis<br /> · Mirando, Mark (mmirando@csrees.usda.gov)  CSREES, USDA<br /> · Proudman, John (miles-to-go@prodigy.net)  ARS Beltsville, MD (retired)<br /> · Rhoads, Doug (drhoads@uark.edu)  University of Arkansas<br /> · Satterlee, Dan (dsatterlee@agctr.lsu.edu)  Louisiana State University<br /> · Siopes, Tom (tom_siopes@ncsu)  North Carolina State University<br /> · Wood, Ben (ben.wood@hybridturkeys.com)  Hybrid Turkeys<br /> <br /> Brief Summary of Minutes of Annual Meeting:<br /> <br /> The business meeting was chaired by David Froman using the following outline: (1) a thanks to Doug Rhoads, (2) future leadership, (3) participation in annual meetings, (4) meeting organization, (5) annual reports, and (6) the 2007 annual meeting. Doug Rhoads was thanked for his organizing the 2006 annual meeting in St. Croix, US Virgin Islands. The quality of accommodations and the meetings structure were enjoyed by all. With respect to group leadership, D. P. Froman agreed to continue as chair. Meeting organization has assumed to forms to date. Whereas the traditional approach has been to share research results by experiment station or experimental objectives, a topical approach also has been used. In view of the groups goal for increased industry participation (preferably VPs of research and development or their representatives), an argument was made in favor of a topical approach; for this affords industry personnel an overview of subjects to be discussed well in advance of the annual meeting. Thus, a compromise approach is to organize presentations by topic within project objectives as was done during the 2006 annual meeting.<br /> <br /> With respect to the S1020 annual report, members were reminded that a single report is to be submitted to NIMSS from the group through the chair to Dr. Hagler. This report entails a synthesis of accomplishments. Thus, members were encouraged to first read the 2005 annual report on-line at NIMSS and then write their contributions with an emphasis on integration as well as the advancement of the projects goals. Only pertinent publications were to be included. Data summaries such as graphs and tables are not acceptable for preparation of the annual report. It is the responsibility of each member to succinctly summarize accomplishments using language that can be understood by a wide audience.<br /> <br /> The advantages and disadvantages of several potential meeting sites were discussed. However, a consensus arose with respect to coastal Georgia as a first choice. Thus, the chair agreed to contact Dr. Jeanna Wilson upon his return to work. Tentative meeting dates were either the 25th and 26th of October or the 1st and 2nd of November, 2007. <br /> <br /> Both Dr. Hagler and Dr. Mirando deemed the level of participation to be acceptable even though a number of participants were unable to attend the annual meeting. This concerned the chair in that the primary objective of the project is collaboration. In view of the distribution of participants throughout the US, the annual meeting may be the only time some participants see each other during the course of a year. <br /> <br /> Accomplishments:<br /> <br /> Countering a long-term decline in the fertility of meat-type chickens<br /> <br /> Doug Rhoads and David Froman completed their initial analysis of RNAs expressed in the chicken reproductive tract. This effort identified 475 novel genes and thereby afforded a new technical paradigm for the application of genomics to the study of reproductive efficiency in poultry. For example, this advance should expedite mapping genes that are major determinants of reproductive efficiency. Rhoads also described a rapid and inexpensive method for DNA isolation suitable for high throughput genotype analysis in poultry.<br /> <br /> Wayne Kuenzel reported pilot studies addressing the role of male broiler breeder behavior in flock fertility. This effort complemented that of Inma Estevez, who addressed the role of environmental enrichment on broiler breeder behavior, male-female aggression in particular. Dr. Estevez performed studies on five commercial broiler breeder farms wherein reproductive performance was measured for control and treated flocks. Environmental enrichment was achieved by allocation of panels, which serve to subdivide space within the house. Environmental enrichment increased egg production by nearly 2%. Likewise, incidence of floor eggs was reduced by 30%. Finally, male home range increased with environmental enrichment. This affords any given male increased potential to meet and then copulate with a larger number of females. Enhanced reproductive performance was attributed to decreased female stress.<br /> <br /> Reproduction in males is compromised by routine vaccination with avian infectious bronchitis virus (AIBV). Janice Bahr continued her investigation of underlying mechanism whereby vaccination induces epididymal dysfunction. Western blot analysis demonstrated that anti-AIBV antibodies bind to sperm. The consequence of antibody binding awaits explanation.<br /> Research conducted by Dan Satterlee demonstrated a link between the hypothalamic-pituitary-adrenal (HPA) axis of dams and the reproductive performance of their female offspring. In this case, lines of quail selected for either low or high stress were used as experimental animals. In other words, experimental birds are characterized by a reduced or heightened reaction of the HPA to a common stressor. The HPA serves to elevate circulating corticosterone in response to environmental stressors. Elevated corticosterone has a negative effect on reproductive efficiency by its action upon the hypothalamic-pituitary-gonadal axis. Whereas this effect has been understood for several decades with respect to birds exposed to an environmental stressor, evidence is emerging that parental stress can adversely affect the reproductive performance of adult offspring. This is attributed, in part, to the fact that corticosterone is a lipid-soluble hormone. Thus, the hormone can move from the bloodstream into the oocytes yolk. Such transmission sets the stage for a maternal hormone altering the performance of progeny. In this case, the fertility of female offspring was determined for the following dams: low stress controls, low stress dams implanted with corticosterone, high stress controls, and high stress dams implanted with corticosterone. The fertility of female offspring was ranked as follows. Fertility of females hatched from eggs laid by low stress control dams was equivalent to that of females hatched from eggs laid by low stress dams implanted with corticosterone. The fertility of these two groups of females was greater than that of females hatched from eggs laid by high stress dams, which in turn, was greater than the fertility of females hatched from eggs laid by high stress dams implanted with corticosterone.<br /> <br /> Research conducted by Judy Grizzle addressed the deleterious role of fungal mycotoxins on reproduction. Though suboptimal fertility is typically attributed to variables such as intense genetic selection for body growth or heat stress, mycotoxin contamination of feed grains is estimated to be 25%. Currently, there are no methods for detoxification of infested grain or ameliorating the effect of ingested infected grain. Work in progress is testing an intervention strategy against mycotoxin exposure in commercial chickens. Likewise, the effect of mycotoxin on postnatal testis development and semen quality will be studied.<br /> <br /> <br /> Developing an adaptive, comprehensive understanding of turkey egg hatchability that can be applied to commercial hatcheries<br /> <br /> Vern Christensen used genetic crosses to evaluate the relationship between cardiac function, embryonic viability, and lines of turkeys. Experimental lines included those selected for body weight and egg production in addition to randombred turkeys. Both sires and dams contribute to cardiac growth and function. This is important because commercial turkey breeding entails crossing a line selected for egg production with a line selected for rapid growth in order to produce commercial breeders.<br /> <br /> <br /> <br /> <br /> Discovering the basis for photorefractoriness in turkeys<br /> <br /> It is well established that thyroid hormone is essential for photosexual stimulation of domestic turkeys. One biological role for thyroid hormone is inducing retraction of glial end-feet that ensheath the terminals of axons from GnRH I. It is also known that photostimulation of photosensitive hens leads to immunoreactive protein expression within the hypothalamus. Such proteins are related to c-fos (known collectively as fos-related antigens; FRA), an immediate early gene associated with neuronal activation. Jim Millam and Tom Siopes tested the hypothesis that thyroid hormone is essential for photo-induced immunoreactive FRA. Turkey hens were fed propylthiouracil (PTU) prior to photostimulation. PTU inhibits thyroid hormone synthesis. Treated and control hens were sacrificed 48 hr after photostimulation. When brain tissue was examined, there was no difference in immunoreactive FRA between treated and control hens. This outcome demonstrated that photo-induced immunoreactive FRA in the turkey hypothalamus is not induced by thyroid hormone. In other words, thyroid-critical events in photostimulation are downstream from induction of immunoreactive FRA. Previous research demonstrated that immunoreactive FRA expression does not occur in photostimulated, photorefractory turkey hens. Consequently, limited GnRH 1 secretion rather than inadequate thyroid hormone most likely accounts for the absence of immunoreactive FRA expression in photostimulated, photorefractory hens.<br /> <br /> <br /> Explaining the CNS integration that drives the hypothalamic-pituitary-gonadal axis<br /> <br /> GnRH is a key neuropeptide affecting the hypothalamic-pituityary-gonadal axis. Wayne Kuenzel reported the completion of a study in which the distribution of GnRHergic neurons was mapped within the chicken brain. In addition, exposure to a long-day photoperiod induced an increase in the number of neurons positive for GnRH with a major nucleus wherein GnRHergic neurons are found. <br /> <br /> A relatively new signal molecule within the hypothalamic-pituitary-gonadal axis is gonadotropin inhibitory hormone (GnIH). Ramesh Ramachandran cloned and characterized cDNA encoding the chicken GnIH receptor. In addition, the polymerase chain reaction (PCR) was used to detect GnIH mRNA within the chicken diencephalon (the central region of the vertebrate brain in which the hypothalamus is found), the anterior pituitary gland, and ovary. GnIH mRNA was not detected within the liver. Real-time PCR demonstrated that GnIH mRNA was greatest within the diencephalon. These experimental outcomes afford the means whereby control points for GnRH secretion can be assessed within a physiological context.<br /> <br /> <br /> Impact Statements:<br /> <br /> 1. The validation of a rapid and inexpensive method for DNA isolation suitable for high throughput genotype analysis will expedite and standardize genomic analyses. Likewise, characterization of the transcriptome within the reproductive tract affords a new tool suitable for the characterization of gene networks that affect reproductive efficiency.<br /> <br /> 2. Critical environmental factors affecting flock performance include diet, photoperiod, and temperature. However, social factors affect reproductive efficiency as well. Environmental enrichment, as outlined by researchers at the University of Maryland, is predicted to yield an additional 24,000 chicks per house per production cycle. Based upon pilot studies conducted on breeder farms owned by one company, this business would produce nearly 14 million additional chicks per year by making a marginal investment in environmental enrichment. <br /> <br /> 3. Apart from genetic effects, the determinants of poultry reproductive efficiency have historically been viewed as factors affecting birds on hand. However, research with quail has demonstrated that stressors acting upon a dam can affect the reproductive performance of adult offspring in the next generation. This realization affords a new paradigm in the analysis of reproductive performance of poultry. This paradigm is applicable to primary breeders; for the degree to which the hypothalamic-pituitary-adrenal axis responds to stressors may warrant consideration in addition to production traits.<br /> <br /> 4. Photorefractoriness is a primary factor limiting production of turkey hatching eggs. Research explaining a series of hormone-driven events continues to refine critical control points within the brain that affect photorefractoriness.<br /> <br /> Publications:<br /> <br /> Bahr, J. M., M. Dalponte, S. J. Janssen, and M. Nakai. 2006. Ion transporters for fluid resorption in the rooster (Gallus domesticus) epididymal region. Animal. Reprod. Sci. 95:331-337.<br /> <br /> Boltz, D. A., C. R. Zimmerman, M. Nakai, D. Bunick, G. Scherba, and J. M. Bahr. 2006. Epididymal stone formation and decreased sperm production in roosters vaccinated with a killed strain of avian infectious bronchitis virus. Avian Diseases (in press).<br /> <br /> Christensen, V. L., J. L. Grimes, R. D. Rowland, and D. T. Ort. 2006. Effect of chelated calcium proteinate fed in the maternal diet of turkey breeders on embryo cardiac physiology. Int. J. Poult. Sci. 5:337-343.<br /> <br /> Christensen, V. L., L. G. Bagley, T. Olson, J. L. Grimes, R. D. Rowland, and D. T. Ort. 2006. Shell thickness of turkey eggs affects cardiac physiology and embryo survival. Int. J. Poult. Sci. 5:796-803.<br /> <br /> Froman, D. P., J. D. Kirby, and D. D. Rhoads. 2006. An expressed sequence tag analysis of the chicken reproductive tract transcriptome. Poult. Sci. 85:1438-1441.<br /> <br /> Jackson, U., D. A. Boltz, M. Nakai, D. Bunick, G. Scherba, and J. M. Bahr. 2006. Prepubertal exposure to the avian infectious bronchitis virus induces epididymal stones in the rooster after puberty. Poult. Sci. 43:280-285.<br /> <br /> Kuenzel, W. J., and C. D. Golden. 2006. Distribution and change in number of gonadotropin-releasing hormone-1 neurons following activation of the photoneuroendocrine system in the chick (Gallus gallus). Cell Tissue Res. 325:501-512.<br /> <br /> Proudman, J. A., and T. D. Siopes. 2006. Potential role of thyroid hormones and prolactin in the programming of photorefractoriness in turkey hens. Poult. Sci. 85:1457-1461.<br />

Publications

Impact Statements

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Report Information

Participants

Bartel, Paul (pab43@psu.edu),The Pennsylvania State University; Berry, Wallace (berrywd@auburn.edu),Auburn University; Bramwell, Keith (bramwell@uark.edu)  University of Arkansas; Froman, David (David.Froman@oregonstate.edu),Oregon State University; Grizzle, Judy (jgrizzle@utk.edu)  University of Tennesee; Hagler, Winston (winston_hagler@ncsu.edu)  N.C.State University; Johnston, Paul (paul_johnston@byu.edu),Brigham Young University;McIntyre, Don (Don.McIntyre@hendrix-genetics.com); Millam, Jim (jrmillam@ucdavis.edu),UC Davis; Mirando, Mark (mmirando@csrees.usda.gov),CSREES, USDA; Navara, Kristien (knavara@uga.edu),University of Georgia; Ramachandran, Ramesh (rameshr@psu.edu),The Pennsylvania State University; Rhoads, Doug (drhoads@uark.edu),University of Arkansas; Satterlee, Dan (dsatterlee@agctr.lsu.edu),Louisiana State University; Settar, Petek (PSettar@hyline.com),Hy-Line International; Siopes, Tom (tom_siopes@ncsu),North Carolina State University; Wilson, Jeanna (jeannw@uga.edu),The University of Georgia

Brief Summary of Minutes

Annual meeting 11-01-2007-11/02/2007.

The business meeting was chaired by David Froman using the following outline: (1) a thanks to Jeanna Wilson, (2) leadership options, (3) the importance of participation in annual meetings, (4) the S1020 annual report, and (5) options for the location of the 2008 annual meeting. Dr. Jeanna Wilson was thanked for her finding an excellent venue for the 2007 annual meeting. The locale and accommodations were enjoyed by all. With respect to leadership, the chair inquired as to whether any other member was interested in such service. There was a consensus that David Froman continue to serve as S1020 chair. As such, the chair requested that Doug Rhoads continue to serve as secretary. With respect to the annual meeting, the chair reiterated the importance of complying to email in a timely fashion. This is the means whereby our business and reporting is conducted, timely flow of information enables the timely construction of a meetings agenda, and such a document can be instrumental in attracting key industry participants. With respect to the annual report, the chair encouraged each member to visit the NIMSS website prior to preparing his or her report. The group was reminded that the primary objective of the project is collaboration. Members were asked to format their accomplishments, impact statements, and publications using language and style consistent with website and the projects express experimental goals. The importance of each participants effort in this regard was reinforced remarks from both Winston Hagler and Mark Mirando. The chair requested input by December 15th so that the annual report could be finalized by years end. Three options were considered for the 2008 annual meeting: western North Carolina / eastern Tennessee, the gulf coast in Alabama, and New Orleans. Due to Dan Satterlees projected short-term participation in the project, it seemed reasonable that New Orleans be given priority. The chair agreed to host the meeting on the West Coast should New Orleans prove to be problematic by winter of 2008. The next annual meeting is scheduled for all day on October 30th and the morning of October 31st. This arrangement should afford reasonable time for presentations and minimize meeting expenses.

Accomplishments

Publications

Impact Statements

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Report Information

Participants

· Bartel, Paul (pab43@psu.edu)  The Pennsylvania State University
· Berry, Wallace (berrywd@auburn.edu)  Auburn University
· Bramwell, Keith (bramwell@uark.edu)  University of Arkansas
· Froman, David (David.Froman@oregonstate.edu)  Oregon State University
· Grizzle, Judy (jgrizzle@utk.edu)  University of Tennesee
· Hagler, Winston (winston_hagler@ncsu.edu)  N.C. State University
· Johnston, Paul (paul_johnston@byu.edu) Brigham Young University
· McIntyre, Don (Don.McIntyre@hendrix-genetics.com)
· Millam, Jim (jrmillam@ucdavis.edu)  UC Davis
· Mirando, Mark (mmirando@csrees.usda.gov)  CSREES, USDA
· Navara, Kristien (knavara@uga.edu)  The University of Georgia
· Ramachandran, Ramesh (rameshr@psu.edu)  The Penn. State University
· Rhoads, Doug (drhoads@uark.edu)  University of Arkansas
· Satterlee, Dan (dsatterlee@agctr.lsu.edu)  Louisiana State University
· Settar, Petek (PSettar@hyline.com)  Hy-Line International
· Siopes, Tom (tom_siopes@ncsu)  North Carolina State University
· Wilson, Jeanna (jeannw@uga.edu)  The University of Georgia

Brief Summary of Minutes

The business meeting was chaired by David Froman using the following outline: (1) a thanks to Jeanna Wilson, (2) leadership options, (3) the importance of participation in annual meetings, (4) the S1020 annual report, and (5) options for the location of the 2008 annual meeting. Dr. Jeanna Wilson was thanked for her finding an excellent venue for the 2007 annual meeting. The locale and accommodations were enjoyed by all. With respect to leadership, the chair inquired as to whether any other member was interested in such service. There was a consensus that David Froman continue to serve as S1020 chair. As such, the chair requested that Doug Rhoads continue to serve as secretary. With respect to the annual meeting, the chair reiterated the importance of complying to email in a timely fashion. This is the means whereby our business and reporting is conducted, timely flow of information enables the timely construction of a meetings agenda, and such a document can be instrumental in attracting key industry participants. With respect to the annual report, the chair encouraged each member to visit the NIMSS website prior to preparing his or her report. The group was reminded that the primary objective of the project is collaboration. Members were asked to format their accomplishments, impact statements, and publications using language and style consistent with website and the projects express experimental goals. The importance of each participants effort in this regard was reinforced remarks from both Winston Hagler and Mark Mirando. The chair requested input by December 15th so that the annual report could be finalized by years end. Three options were considered for the 2008 annual meeting: western North Carolina / eastern Tennessee, the gulf coast in Alabama, and New Orleans. Due to Dan Satterlees projected short-term participation in the project, it seemed reasonable that New Orleans be given priority. The chair agreed to host the meeting on the West Coast should New Orleans prove to be problematic by winter of 2008. The next annual meeting is scheduled for all day on October 30th and the morning of October 31st. This arrangement should afford reasonable time for presentations and minimize meeting expenses.

Accomplishments

Countering a long-term decline in the fertility of meat-type chickens<br /> <br /> Doug Rhoads published his technique outlining a rapid and inexpensive method for isolation of DNA from poultry tissue samples. This advance  along with a full genome evaluation for single nucleotide polymorphisms (SNPs) -- sets the stage for genomic analysis of male chickens characterized with one of two distinct phenotypes known to limit male fertility. In other words, the capability now exists to discover chromosomal regions to be used as quantitative trait loci (QTLs) for semen quality. Doug Rhoads and David Froman obtained an industry award for this purpose. Their point of application will be pedigree line broiler breeder males. Doug Rhoads continued his study of novel RNAs within the chicken reproductive tract. Many of these RNAs appear to be non-coding, polyadenylated gonad-specific RNAs whose appearance within male and female poultry is coincident with onset of meiosis. Historically, gametogenesis has been described in terms of hormone signaling within the hypothalamo-pituitary-gonadal axis. However, the discovery of novel RNAs may enable description of gametogenesis in terms of the interplay between hormones and gonadal gene networks.<br /> <br /> Fertility in meat-type chickens is, in part, determined by effective copulation. To date, male physical well-being, social dominance, male age and experience, as well as cryptic female choice have been identified as contributing variables. Consequently, a pilot study conducted by the Kuenzel laboratory was significant in that a link was sought between neural structures and male sexual behavior. Specifically, males were characterized as aggressive or non-aggressive based upon their mating behavior. Thereafter, the following variables were measured: fertility, blood plasma testosterone, and immunostaining for gonadotropin releasing hormone 1 (GnRH-1) along with arginine vasotocin (AVT) within selected neural structures. Initially, aggressive males were subfertile and had lower blood plasma testosterone in comparison to non-aggressive males. However, this effect was not independent of time. AVT immunostaining may prove to be a more useful variable that blood plasma testosterone because a significant positive correlation was found (r =0.81) between AVT fiber density within the lateral septum and mounting attempts. In contrast, no difference was observed with respect to the density of GnRH-1 neurons within the bed nucleus of the pallial commissure, the primary nucleus in which GnRH-1 neurons are located.<br /> <br /> Dan Satterlees quail model continues to provide interesting insights between the responsiveness of the hypothalamo-pituitary-adrenal axis and reproductive performance. Specifically, genetic selection for exaggerated hypothalamic-pituitary-adrenal responsiveness within a high stress line quail (HS) yields dams whose male offspring are characterized by diminished reproductive capacity as evidenced by secondary sexual characteristics and testis weight. Thus, the status of a dams hypothalamo-pituitary-adrenal axis has been shown to affect the reproductive potential of female and male offspring alike. This effect is attributed to transmission of the lipid-soluble stress hormone corticosterone from the dam into the yolk of the egg from which a chick develops. Male mating behavior was also found to differ between HS and low stress (LS) lines as evidenced by a two-way choice test. Based upon direction of first travel, affiliation preference, and time spent near a female, sexually mature but naïve LS males preferred an LS hen as a companion  as did comparable HS males. In contrast, more time was spent near HS females when male test subjects were produced by dams implanted with corticosterone. This effect was observed with treated hens from both the LS and HS lines. <br /> <br /> In review, the collective work of David Froman, Doug Rhoads, and Dan Satterlee is enabling new insights into the effect of genes on reproductive potential. Likewise, the collective work of Wayne Kuenzel and Dan Satterlee is enabling new questions to be asked about the effect of gene-environment interaction reproductive potential. However, reproductive potential can also be affected by dietary factors  sometimes in an unexpected and uncontrolled manner. In this regard, research conducted by Judy Grizzle and Wallace Berry addressed T-2 toxin detoxification and effects of phytoestrogens, respectively.<br /> <br /> Molds are ubiquitous in nature and the extent to which mycotoxins contaminate grain crops is difficult to control. Judy Grizzle investigated a potential intervention strategy for trichothethene poisoning. The enzyme 3-O-acetyltransferase can acetylate T-2 toxin and thereby appreciably reduce toxicity. The efficacy of this approach was tested in vitro by exposing chicken macrophages to levels of T-2 toxin comparable to those found within field grains. Macrophages were unaffected when co-incubated with 1 nM purified 3-O-acetyltransferase and then challenged with 200 nM T-2 toxin. The protective effect of the enzyme was lost when macrophages were exposed to a 10-fold increase in T-2 toxin even though the enzymes concentration was increased to 5 nM. Field studies will follow. As evidenced by collaborative work with Dan Satterlee, low level mycotoxin contamination of feed is expected to exacerbate the poor reproductive performance of males characterized by elevated blood corticosterone.<br /> <br /> Unlike mycotoxins, phytoestrogens are inherent to poultry diets. For example, chickens of all ages are exposed to relatively potent estrogenic isoflavones by virtue of eating a soy-based diet. Previous work from Wallace Berrys laboratory confirmed genistein as the principal soybean isoflavone with the potential to affect chick oviduct development. Therefore, an experiment was performed testing the effect of genistein on traits subject to estrogen. Day-old female chicks were fed a diet in which dried egg white served as the protein source. This eliminated any confounding effect from dietary genistein. Sesame oil and diethylstilbesterol served as negative and positive controls. All experimental compounds were administered daily by gavage to one group of chicks and by subcutaneous injection to another. The presence of genistein within blood plasma was confirmed by HPLC. The estrogenic effect of diethylstilbesterol was mimicked by genistein as both compounds increased oviduct weight as a percentage of body weight, induced hepatic vitellogenin synthesis, and altered behavior. In summary, should bloodstream genistein concentration reach a threshold, then brain and liver functions are subject to the effect of phytoestrogen as is oviduct development.<br /> <br /> Discovering the basis for photorefractoriness in turkeys<br /> <br /> James Millam used double-label immunochemistry to document the appearance of proteins within the turkey hens tuberal hypothalamus in response to photostimulation. In general, brain tissue is a mixture of neurons  or bundles of their axons that project towards neurons at other sites within the brain or spinal cord  and glial cells. The proteins induced by photostimulation are known collectively as fos-related antigens (FRA) in which fos- pertains to the gene c-fos. The expression of FRA was largely restricted to cells that also expressed glial acidic fibrillary protein (GFAP), which serves as a marker for glial cells such as astrocytes and tanycytes. Fos-related antigens do not appear within the hypothalamus of photorefractory turkeys. Therefore, the GFAP-positive cells comprise a neurological locus of failure in photorefractoriness. Related experimentation entailed the localization of the enzyme deiodinase II in newly photostimulated turkey hens. As evidenced by immunohistochemistry, deiodinase II co-localized with staining for FRA and GFAP. The significance of this discovery can be explained as follows. A critical signal within the hypothalamo-pituitary-gonadal axis is gonadotropin releasing hormone (GnRH). This neuropeptide is secreted from hypothalamic neurons, enters the bloodstream, and then acts downstream on cells within the pituitary gland. Deiodinase II is required for the conversion of the prohormone tetraiodothyronine to the active hormone triiodothyronine. Thus, within a few hours of exposure to long day length, local production of triiodothyronine induces production of growth factors that ultimately lead to the retraction of glial end-feet. These end-feet cover the ends of axons from which GnRH is secreted. In other words, the triiodothyronine signal serves to remove a physical barrier that may limit entry of GnRH into the bloodstream. Moreover, immunoreactivity to deiodinase II was absent from the rostral and central regions of the tuberal hypothalamus in photorefractory hens. In summary, cessation of egg production in photorefractory hens can now be traced back to the failure of deioidinase II to appear within GFAP-positive cells within the tuberal hypothalamus.<br /> <br /> As explained above, long day length and thyroid hormones are required for egg production in the turkey. However, these factors are also linked with programming for photorefractoriness, which serves to limit egg production. Programming for photorefractoriness is believed to occur soon after onset of photostimulation. Tom Siopes and James Millam explored the possibility that thyroid hormones serve to enable programming for photorefractoriness. This experiment was performed by treating hens with propylthiouracil for 12 weeks following photostimulation. As evidenced by the concentration of thyroid hormones in the bloodstream of treated and control hens, propylthiouracil was efficacious as an anti-thyroid agent. As expected, egg production commenced once hens were no longer treated with propylthiouracil. However, the pattern at which the egg production of treated hens declined with time was comparable to that of control hens. Therefore, thyroid hormones do not appear to be essential for programming for photorefractoriness during the first 12 weeks of photostimulation.<br /> <br />

Publications

Bailes, S., J. Devers, J. D. Kirby, and D. D. Rhoads. 2007. An inexpensive, simple protocol for DNA isolation from blood for high throughput PCR or restriction endonuclease-based genotyping. Poult. Sci. 86:102-106.<br /> <br /> Lábaque, M. C., D. G. Satterlee, D. A. Guzman, and R. H. Marin. 2007. Ontogeny of the cloacal gland in male Japanese quail classified in a T-maze. Poult. Sci. 86:2013-2119.<br /> <br /> Madison, F. N., A Jurkevich, and W. J. Kuenzel. 2007. Sex differences in plasma corticosterone release in undisturbed chickens (Gallus gallus) in response to arginine vasotocin and corticotrophin releasing hormone. Gen. Comp. Endocrinol. (in press), available on line:doi:1016/j.ygen.2007.08.014.<br /> <br /> Perrin, S. L., J. Lin, and J. M. Grizzle. 2007. The iosolation and purification of tricothethene 3-O-acetyltransferase for protection against T-2 toxin. Department of Animal Science Research Report, University of Tennessee. http://animalscience.ag.utk.edu/pdf/Reports/2007/IsolationPurification-SLP-JL.pdf<br /> <br /> Satterlee, D. G., C. A. Cole, and S. A. Castille. 2007. Maternal corticosterone further reduces the reproductive function of male offspring hatched from eggs laid by quail hens selected for exaggerated adrenocortical stress responsiveness. Poultry Sci. 86: 572-581.<br /> <br /> Satterlee, D. G., M. Tong, S. A. Castille, and R. H. Marin. 2007. Cloacal gland growth differences in high and low plasma corticosterone stress response line male quail reared under short daylengths. Poultry Sci. 86: 1213-1217.<br /> <br /> Siopes, T. D. 2007. Lighting for summer egg production in turkeys: Day length and light intensity. Poult. Sci. 86:2413-2419.

Impact Statements

1. Specific chromosomal regions have been associated with traits that determine semen quality: sperm viability and mobility of viable sperm. The development of genetic tests for these regions should enable the identification of alleles affecting semen quality as well help determine the relative importance of individual alleles within a group. As such, this effort should eventually help primary breeders use DNA from sexually immature individuals to select for adult male fitness.
2. A relationship was described between a specific region of the brain and male copulatory behavior. If this relationship can be confirmed, then a means will be gained for exploring two related novel questions. First, can copulatory behavior be explained in terms of specific groups of CNS neurons? And if so, what variables serve to affect the nature or organization of such neurons within males?
3. The relationship between a dams hypothalamo-pituitary-adrenal axis and the reproductive potential of her progeny warrant attention from primary breeders. Likewise, breeder hen management may warrant change for the express purpose of minimizing laying hen stress and thereby corticosterone content within hatching eggs. In this regard, egg yolk corticosterone may prove to serve as a useful criterion for geneticists and flock managers alike.
4. Enzymatic detoxification of T-2 mycotoxin demonstrated the potential for enhancing flock performance by treating field grain prior to ration formulation. Should this approach prove effective in field trials, then a novel and environmentally safe solution may be found that limits the effect of a toxic feed contaminant.
5. The dietary content of phytoestrogens may warrant consideration in the overall assessment of feed quality.
6. Photorefractoriness limits annual egg production per turkey hen. Immunocyto- chemistry has demonstrated that failure to express mRNA for an enzyme within a specific type of brain cell results in a failure of the brain to stimulate the pituitary gland, which in turn compromises egg production. The experimental outcomes presented in this report are the first known to link a specific cell type within a specific region of the brain with an abortive physiological process in poultry.
7. Whereas thyroid hormones enable egg production in response to photostimulation, they do not play a concomitant role in programming photorefractoriness at the onset of photostimulation. Therefore, programming may depend upon the interaction between encephalic photoreceptors and glial cell function within the hypothalamus.

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Report Information

Participants

Bramwell, Keith (bramwell@uark.edu)  University of Arkansas;
El Halawani, Mohamed (elhal001@umn.edu)  University of Minnesota;
Froman, David (David.Froman@oregonstate.edu)  Oregon State University;
Grizzle, Judy (jgrizzle@utk.edu)  University of Tennessee;
Hagler, Winston (winston_hagler@ncsu.edu)  North Carolina State University;
Huisinga, Jared (jared.huisinga@life-scienceinnovations.com)  Life Science Innovations;
Johnson, Pat (paj1@cornell.edu)  Cornell University;
Jurkevich, Alexander (ajurkev@uark.edu)  University of Arkansas;
Kuenzel, Wayne (wkuenzel@uark.edu)  University of Arkansas;
McIntyre, Don (Don.McIntyre@hendrix-genetics.com);
Millam, Jim (jrmillam@ucdavis.edu)  UC Davis;
Mirando, Mark (mmirando@csrees.usda.gov)  CSREES, USDA;
Poe, Bob (bob.poe@life-scieneinnovations.com)  Life Science Innovations;
Rhoads, Doug (drhoads@uark.edu)  University of Arkansas;
Satterlee, Dan (dsatterlee@agctr.lsu.edu)  Louisiana State University;
Siopes, Tom (tom_siopes@ncsu)  North Carolina State University

Brief Summary of Minutes

Brief Summary of Minutes of Annual Meeting:

The business meeting was chaired by David Froman using the following outline: (1) a thanks to Dan Satterlee, (2) leadership options within S1020, (3) the importance of participation in annual meetings, (4) the need to draft a new multistate project should there be a consensus to do so, (5) S1020 annual report, and (6) options for the location of the 2008 annual meeting. Dr. Dan Satterlee was thanked for his finding a lively venue for the 2008 annual meeting. With respect to leadership, the chair once again inquired as to whether any other member was interested in such service. Doug Rhoads (S1020 secretary) questioned his further participation. Doug is not recognized as a formal participant by the Arkansas Experiment Station and therefore receives no compensation for his attending the annual meeting. Whereas the position of S1020 secretary was not resolved, David Froman agreed to continue as S1020 chair. In view of the impending project rewrite, the chair reiterated the importance of responding to email in a timely fashion. This form of communication enables the project to operate. With respect to annual reports, Mark Mirando encouraged each member to condense annual reports sent to the S1020 chair. Specifically, members were asked to be sure to distinguish between accomplishments and impact statements and then format these items as well as publications using language and style consistent with NIMSS website. Once again, the importance of each participants effort in this regard was reinforced remarks from both Winston Hagler and Mark Mirando. The S1020 chair is requesting input no later than December 5th in this regard.

The chair read a prepared statement drafted prior to the annual business meeting. This statement follows:

S1020 may be viewed as either the reinvention or remnant of a long-existing project that addressed turkey reproduction. The change in the projects scope, i.e. poultry rather than turkey reproduction, enabled long-term participants to continue and new participants to join. One of the groups challenges 4 to 5 years ago was loss of critical mass. While some gains were made  most noticeably from the University of Arkansas  this challenge remains a substantive one.

One advantage to participation is that our meeting offers more science (in poultry reproduction) than the annual meeting of PSA and more camaraderie (for poultry scientists) than the annual meeting of SSR. Our meetings are short in duration and, on the average, have been held in interesting places. Nonetheless, attendance is a chronic issue. This is felt most keenly by those who stage our annual meeting; for these people are asked to assure that a block of rooms will be filled and asked in a contractual manner. Granted, once this is done, the responsibility is not as burdensome as it first appears, and yet it is a serious commitment that warrants ones attention and effort.

As is true for any human group or effort, members of our group can be categorized. We have stalwarts, off-and-ons, and some no-shows, even though their names are listed within the NIMSS websites Appendix E. In short, attendance matters. Our annual roster represents the tip of the ice berg, this ice berg is supposed to be collaboration between Experiment Stations, and whether you embrace global warming or not, our ice berg may be shrinking. We have reached another turning point . . . .

Though it was questioned whether a multistate project in poultry reproduction continue, there seemed to be a consensus that an attempt be made to draft a new project. In part, this was based upon the value of the groups efforts as seen by Winston Hagler and Mark Mirando. Consequently, the chair proposed three broad topical areas to be addressed as objectives within a new multistate project: (1) photoperiodicity, (2) gametes, and (3) the neural basis for reproductive behavior. These areas were chosen a priori based upon outstanding problems within the poultry industry, research interests of S1020 participants at large, and the value of poultry species as experimental animals in the field of reproductive biology. With respect to a writing committee, it was agreed that Mohamed El Halawani and Tom Siopes would lead the draft for the first objective. Pat Johnson volunteered to help the chair draft the second objective, and Wayne Kuenzel agreed to lead the draft of the third objective.

It was decided that the next annual meeting of S1020 would be held in San Francisco, California. Jim Millam (UC Davis) agreed to host the meeting. Optional dates included the last two weeks in October and the first week in November 2009. This approach was used to allow Jim Millam time to assess local accommodations and minimize scheduling conflicts for participants who must attend other meetings in this time frame.

Accomplishments

Publications

Impact Statements

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Report Information

Participants

El Halawani, Mohamed (elhal001@umn.edu) University of Minnesota;
Froman, David (David.Froman@oregonstate.edu) Oregon State University;
Hagler, Winston (winston_hagler@ncsu.edu) North Carolina State University;
Johnson, Pat (paj1@cornell.edu) Cornell University;
Jurkevich, Alexander (ajurkev@uark.edu) University of Arkansas;
Kuenzel, Wayne (wkuenzel@uark.edu) University of Arkansas;
McIntyre, Don (Don.McIntyre@hendrix-genetics.com);
Millam, Jim (jrmillam@ucdavis.edu) UC Davis;
Mirando, Mark (mmirando@csrees.usda.gov) CSREES, USDA;
Rhoads, Doug (drhoads@uark.edu) University of Arkansas

Brief Summary of Minutes

The business meeting was chaired by David Froman using the following outline: (1) a thanks to Jim Millam, who served as host, (2) meeting site for 2010, (3) a discussion of the disconnect between the number of project participants and the number of people that attend the annual meeting, (4) a rationale for eliminating two objectives within the new project in order to make the number of attendants commensurate with the number of participants, (5) industry input, and (6) an impromptu discussion about experiment station maintenance of facilities critical to poultry research.

Once again, Jim Millam did an excellent job as our host in San Francisco. Unfortunately, the meeting was poorly attended, which caused some uncertainty about the magnitude of the registration fee per participant. Nonetheless, the meeting was deemed productive, and a decision was made to have the 2010 meeting at the University of Arkansas in Fayetteville, AR. Doug Rhoads agreed to serve as host. This choice was based upon a central location within the U.S., a reduced meeting cost, and a minimal financial constraint placed upon the host in advance of the meeting.

Additional discussion about participation resulted in a suggestion that the membership be surveyed relative to their interest level in the project. The chair agreed to draft, disseminate, and compile responses. Though this effort was subsequent to the annual meeting, the results of this survey are included in this report because they are pertinent to much of the discussion within the 2009 business meeting.

Each person who requested to act in the capacity of a scientist within the new project (n = 16) was sent a survey with 5 questions. Each person had approximately 3 weeks to respond. The response rate was 56%. The questions asked about: (1) interest level in collaboration as defined by the project, (2) interest level in the projects annual meeting, (3) the feature of the annual meeting most valued, (4) the reason why the 2009 meeting was not attended if the person was not in attendance, and (5) whether one would be more likely to attend the projects annual meeting if this meeting were held in conjunction with the annual meeting of the Poultry Science Association.

There were clear majorities with respect to the first three questions. Eighty-nine percent of respondents expressed a high level of interest in collaboration within the context of a multistate project. Sixty percent of respondents had a high level of interest in attending the annual meeting. The remaining 40% had a medium interest level. Thus, all respondents were interested in attending the annual meeting, and 72% deemed networking, discussing experimental outcomes, and planning experiments to be the most important feature of the meeting. Therefore, these collective outcomes were consistent with the nature of the project and the purpose of the annual meeting.

In contrast to the first three questions, there was no clear response to the last two questions. Only two people responded to the fourth question, and these were split between inadequate funds and a schedule conflict.

With respect to funding, a portion of Hatch funds are designated for multistate projects but such funds are used differently by different experiment stations. If the bulk of appropriated dollars are used for faculty salaries, then very little money may be available for out-of-state travel. In contrast, other experiment stations pay for one faculty member from that institution to attend an annual meeting. Consequently, it is incumbent upon each participant to determine their situation, e.g. availability of experiment station funds, grant money, willingness to use personal frequent flyer miles, etc., and then use this knowledge to assess the likelihood of participating in the new project.

Finally, respondents were split with respect to having the annual meeting in conjunction with PSA: 55% answered yes, 45% answered no. It is interesting to note that 50% of those who answered no have served as the chair and secretary/treasurer of the project since it began in 2004 and who, at present, appear to be trapped in these incarnations for the foreseeable future. Consequently, any such change in the annual meeting will require a regime change.

Accomplishments

Click on Copy of Minutes above for Accomplishments report

Publications

Bailes, S., J. Devers, J. D. Kirby, and D. D. Rhoads. 2007. An inexpensive, simple protocol for DNA isolation from blood for high throughput PCR or restriction endonuclease-based genotyping. Poult. Sci. 86:102-106.<br /> <br /> Bahr, J. M., M. Dalponte, S. J. Janssen, and M. Nakai. 2006. Ion transporters for fluid resorption in the rooster (Gallus domesticus) epididymal region. Animal. Reprod. Sci. 95:331-337.<br /> <br /> Bilcik, B., and I. Estévez. 2005. Impact of male-male competition and morphological traits on mating strategies and reproductive success in broiler breeders. Appl. Anim. Behav. Sci. 92:307-323.<br /> <br /> Bilcik, B., I. Estévez, and E. Russek-Cohen. 2005. Reproductive success of broiler breeders in natural mating systems: The effect of male-male competition, sperm quality, and morphological characteristics. Poult. Sci. 84:1453-1462. <br /> <br /> Boltz, D. A., C. R. Zimmerman, M. Nakai, D. Bunick, G. Scherba, and J. M. Bahr. 2006. Epididymal stone formation and decreased sperm production in roosters vaccinated with a killed strain of avian infectious bronchitis virus. Avian Diseases 50:594-598.<br /> <br /> Christensen, V. L., J. L. Grimes, R. D. Rowland, and D. T. Ort. 2006. Effect of chelated calcium proteinate fed in the maternal diet of turkey breeders on embryo cardiac physiology. Int. J. Poult. Sci. 5:337-343.<br /> <br /> Christensen, V. L., L. G. Bagley, T. Olson, J. L. Grimes, R. D. Rowland, and D. T. Ort. 2006. Shell thickness of turkey eggs affects cardiac physiology and embryo survival. Int. J. Poult. Sci. 5:796-803.<br /> <br /> El Halawani, M., S. W. Kang, B. Leclerc, S. Kosonsiriluk, and Y. Chaiseha. 2009. Dopamine-melatonin neurons in the avian hypothalamus and their role as photoperiodic clocks. Gen. Comp. Endocrinol. 163:123-127.<br /> <br /> Froman, D. P., and A. J. Feltmann. 2005. Fowl (Gallus domesticus) sperm motility depends upon mitochondrial calcium cycling driven by extracellular sodium. Biol. Reprod. 72:97-101<br /> <br /> Froman, D. P., and J. D. Kirby. 2005. Sperm mobility: Phenotype in roosters (Gallus domesticus) determined by mitochondrial function. Biol. Reprod. 72:562-567.<br /> <br /> Froman, D. P., J. D. Kirby, and D. D. Rhoads. 2006. An expressed sequence tag analysis of the chicken reproductive tract transcriptome. Poult. Sci. 85:1438-1441.<br /> <br /> Jackson, U., D. A. Boltz, M. Nakai, D. Bunick, G. Scherba, and J. M. Bahr. 2006. Prepubertal exposure to the avian infectious bronchitis virus induces epididymal stones in the rooster after puberty. Poult. Sci. 43:280-285.<br /> <br /> Jurkevich, A. L. R. Berghman, L. E. Cornett, and W. J. Kuenzel. 2008. Immunohistochemical characterization of chicken pituitary cells containing the vasotocin VT2 receptor. Cell Tiss. Res. 333:253-262.<br /> <br /> Kang, S.W., A. Thayananuphat, I. Rozenboim, J. R. Millam, J. A. Proudman and M. E. El Halawani. 2006. Expression of hypothalamic GnRH-I mRNA in the female turkey at different reproductive states and following photostimulation. Gen. Comp. Endocrinol. 146:91-99.<br /> <br /> Kuenzel, W. J., and C. D. Golden. 2006. Distribution and change in number of gonadotropin-releasing hormone-1 neurons following activation of the photoneuroendocrine system in the chick (Gallus gallus). Cell Tissue Res. 325:501-512.<br /> <br /> Lábaque, M. C., D. G. Satterlee, D. A. Guzman, and R. H. Marin. 2007. Ontogeny of the cloacal gland in male Japanese quail classified in a T-maze. Poult. Sci. 86:2013-2119.<br /> <br /> Li, H., J. Proudman, and W. J. Kuenzel. 2009. Differential regulation of gene expression and release of FSH and prolactin by long day and sulfamethazine in chicks. Gen. Comp. Endocrinol. 161:262-266.<br /> <br /> Madison, F.N., A. Jurkevich, and W. J. Kuenzel. 2008. Sex differences in plasma corticosterone release in undisturbed chickens (Gallus gallus) in response to arginine vasotocin and corticotrophin releasing hormone. Gen. Comp. Endocrinol. 155:566-573.<br /> <br /> <br /> Madison, F. N., A Jurkevich, and W. J. Kuenzel. 2008. Sex differences in plasma corticosterone release in undisturbed chickens (Gallus gallus) in response to arginine vasotocin and corticotrophin releasing hormone. Gen. Comp. Endocrinol. 155:566-573.<br /> <br /> Perrin, S. L., J. Lin, and J. M. Grizzle. 2007. The iosolation and purification of tricothethene 3-O-acetyltransferase for protection against T-2 toxin. Department of Animal Science Research Report, University of Tennessee. http://animalscience.ag.<br /> utk.edu/pdf/Reports/2007/IsolationPurification-SLP-JL.pdf<br /> <br /> Proudman, J. A., and T. Siopes. 2005. Thyroid hormone and prolactin profiles in male and female turkeys following photostimulation. Poult. Sci. 84:942-946.<br /> <br /> Proudman, J. A., and T. D. Siopes. 2006. Potential role of thyroid hormones and prolactin in the programming of photorefractoriness in turkey hens. Poult. Sci. 85:1457-1461.<br /> <br /> Rathiam, T., and W. J. Kuenzel. 2005. Attenuation of gonadal response to photostimulation following ablation of neurons in the lateral septal organ of chicks. Brain Res. Bull. 64:455-461.<br /> <br /> Satterlee, D. G., C. A. Cole, and S. A. Castille. 2007. Maternal corticosterone further reduces the reproductive function of male offspring hatched from eggs laid by quail hens selected for exaggerated adrenocortical stress responsiveness. Poultry Sci. 86: 572-581.<br /> <br /> Satterlee, D. G., M. Tong, S. A. Castille, and R. H. Marin. 2007. Cloacal gland growth differences in high and low plasma corticosterone stress response line male quail reared under short daylengths. Poultry Sci. 86: 1213-1217.<br /> <br /> Scanes, G. G., S. Jeftinija, A. Glavaski-Joksimovic, J. A. Proudman, and C. Aramburo. 2005. The anterior pituitary gland: Lessons from livestock. Domestic Anim. Endocrinol. 29:23-33.<br /> <br /> Schmidt, J. B., C. A. Cole, R. B. Zanes, and D. G. Satterlee. 2009. Length of incubation and hatchling body weight in quail selected for reduced or exaggerated adrenocortical responsiveness to brief restraint. Brit. Poult. Sci. 50:266-271.<br /> <br /> Siopes, T. 2005 Spontaneous recovery of photosensitivity by turkey breeder hens given prolonged exposure to long day lengths. Poult. Sci. 84:1470-1476.<br /> <br /> Siopes, T. D. 2007. Lighting for summer egg production in turkeys: Day length and light intensity. Poult. Sci. 86:2413-2419.<br /> <br /> Siopes, T. D, and J. A. Proudman. 2008. Exposure duration to long day lengths associated with the expression of photorefractoriness in turkey hens. Poult. Sci. 88:191-198.<br /> <br /> Steinman, M. Q., S. C. Dinius, T. D. Siopes, and J. R. Millam. 2008. Photostimulated expression of type 2 iodothyronine deiodinase mRNA is greatly attenuated in the rostral tuberal hypothalamus of the photorefractory hen. J. Neuroendocrinol. 20:1260-1269.<br /> <br /> Wilhelms, K. W., S. A. Cutter, J. A. Proudman, L. L. Anderson, and C. G. Scanes. 2005. Atrazine and the hypothalamo-pituitary-gonadal axis in sexually maturing precocial birds: Studies in male Japanese quail. Toxicological Sci. 86:152-160.<br /> <br /> <br /> <br />

Impact Statements

1. Traditionally, hatching egg quality has been viewed in terms of egg size, embryonic genetic potential, shell quality, and incubation conditions. However, a dams predisposition towards stressor-induced adrenocortical responsiveness is a new variable for poultry breeders, flock managers, and hatchery operators to consider.
2. Response to stress, courtship behavior, and agonistic behavior can now be understood in terms of gene expression within specific sets of neurons within the brain. This enables the identification of neural networks underlying specific types of behavior.
3. The identification of glial cell phenotypes associated with photorefractoriness will enable the development of a new generation of hypotheses directed towards the precise mechanism by which photorefractoriness develops under long-day photostimulation and how it dissipates under short-day photostimulation

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