S289: Factors Associated with Genetic and Phenotypic Variation in Poultry: Molecular to Populational

(Multistate Research Project)

Status: Inactive/Terminating

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SAES-422 Reports

Annual/Termination Reports:

[07/09/2004] [05/31/2005]

Date of Annual Report: 07/09/2004

Report Information

Annual Meeting Dates: 10/19/2003 - 10/20/2003
Period the Report Covers: 10/01/1999 - 09/01/2004

Participants

Aggrey, S. (saggrey@uga.edu) - University of Georgia; Anthony, N. (nanthony@uark.edu) - University of Arkansas; Berry, Wallace (berrywd@auburn.edu) - Auburn University; Barbato, G. (gfb1@psu.edu) - Penn State University; Grizzle, Judy (jgrizzle@utk.edu) - University of Kentucky; Maurice, D. (dmrc@clemson.edu) - Clemson University; Nahashon, Samuel (snahashon@tnstate.edu) - Tennesee State University; Peebles, D. (dep2@na.msstate.edu) - Mississippi State University; Smith, Edward (esmith@vt.edu) - Virginia Tech; Qureshi, Muquarrab (mqureshi@csrees.usda.gov) - CSREES/USDA

Brief Summary of Minutes

The 2003 meeting was called to order 9:00 am October 19th at the YMCA Blue Ridge Assembly, Blue Ridge, N. Carolina by Chair S. Aggrey (Georgia). This year?s meeting was hosted by the University of Tennessee (Grizzle). Representatives were present from 9 of 10 stations.

Administrative Reports:

Dr. Cherry was unable to attend this year due to a conflict with another meeting, so there was no report from the Administrative Advisor.

Dr. Muquarrab Qureshi, USDA Program Leader of the Animal Genetics program and our new USDA/CSREES representative presented current CSREES funding distribution. The National Research Initiative (NRI) research proposals have yet to be approved for distribution, but should be released soon. Earliest anticipated deadlines will be December, 2003. Proposals will move to a multi state, highly integrated approach utilizing research, education, and extension components. Further information can be obtained at the NRI web site http://www.reeusda.gov/nri.

The proposed 2004 CSREES budget is essentially flat. Appropriations for 2003 totaled 1.126 billion. The House of Representatives 2004 proposal is 1.120 billion while that of the senate is 1.129 billion. Lets hope that the Senate version persists.

Dr. Qureshi also gave us information on the National Information Management and Support System (NIMSS) and congressional funding for the Initiative for Future Agriculture and Food Systems (IFAFS). Funding for IFAFS is authorized, but not appropriated for FY 2004 - $140M, FY 2005 - $160M, and FY 2006 and beyond at $200M. NIMISS contains information on multi state projects both active and proposed and can be accessed through http://www.lgu.umd.edu (requires id and password).

Various CSREES staffing vacancies were discussed and the e-mail address for CSREES has been changed to csrees.usda.gov.

Station Reports:
Station reports were presented and will be posted on the project web site maintained by G. Barbato at http://gfb.cas.psu.edu. Representatives should send yearly summaries ( < 1 page), impact statements, and the full station report to Dr. Barbato as in years past, so that reports can be posted on the web site.

Business Meeting:
The business meeting was called to order by S. Aggrey. The primary order of business involved the revision/re-submission of the project in 2004. After discussion, the proposed title of the new project will be:

Integrative Functional and Physiological Genetics of Poultry.

Proposed objectives will include:

1. To determine the effects of selection, gene introgression and crossing on genetic homeostasis.

2. To determine the interactions among genetic and non-genetic factors
on mechanisms involved in expression of production phenotypes.

3. Evaluate individual loci and resultant protein expression on performance parameters.

Stations that expressed an interest in the new project were: Alabama, Arkansas, Georgia, Mississippi, Pennsylvania, South Carolina, Tennessee (University of Tennessee and Tennessee State University), and Texas. It was suggested that researchers at Ohio, Maryland, or Louisiana might be interested in participating in the project. Offers will be extended to interested parties to join the project.

President elect, L. Cartwright will assume responsibilities of the group in 2004. Election of a Vice Chair was not conducted since this is the first year of Dr. Cartwright?s 2 year Chairmanship. J. Grizzle will remain as secretary until next year.

The meeting was adjourned at noon, October 20th.

Minutes Attachment:

Attachment

Accomplishments

Publications

Impact Statements

Date of Annual Report: 05/31/2005

Report Information

Annual Meeting Dates: 10/30/2004 - 11/01/2004
Period the Report Covers: 09/01/1999 - 10/01/2004

Participants

S. E. Aggrey, Georgia; N. B. Anthony, Arkansas; W. D. Berry, Alabama; G. F. Barbato, Pennsylvania; A. L. Cartwright, Texas; J. G. Grizzle, Tennessee; D. V. Maurice, South Carolina; S. N. Nashoon, Tennessee; K. E. Nestor, Ohio; E. D. Peebles, Mississippi; P. B. Siegel, Virginia (retired); E. J. Smith, Tuskegee and Virginia

Brief Summary of Minutes

Accomplishments

The objectives of S-289 regional project were: 1). To determine the effect of selection, gene introgression and crossing on genetic homeostasis. 2). To determine the interaction of genetic and non-genetic factors on the mechanisms involved in the expression of performance phenotypes. 3). To evaluate ontogenic factors associated with developmental stability. Ontogenic, environmental, and nutritional factors affecting genetic expression of traits were project objectives for this proposal. Much has been learned about the physiological consequences to long term genetic selection for growth, reproduction, antibody response, and susceptibility to disease in chickens and turkeys. Comparison of genomic sequences, analysis of expressed sequence tags, and single nucleotide polymorphisms have attenuated gene discovery in chickens and turkeys. Numerous studies reaffirmed the environmental, nutritional, and managerial impacts on growth and reproductive performance in commercial chickens, turkeys, quail and guinea fowl. As a result, nearly 150 referred publications have come from collaborations and efforts of project members. Described below are accomplishments of the S-289 project group for the period of 1999-2004. Selection studies for growth and reproduction have been conducted at Ohio, Arkansas, Pennsylvania, and Virginia. At all stations selection projects have focused on an understanding of the physiological and reproductive complications associated with long-term selection for growth and carcass yield. In chickens, growth to different ages has different genetic architecture as compared to evaluation of body weight at a fixed age. Generally, selection studies for growth are and have been in response to industry concerns regarding depletion of genetic variability, and the continued pressure to select chickens at younger ages. In chickens fertility was positively correlated with growth to 14 days of age but negatively correlated with growth to 42 days of age. Differences were primarily due to negative correlations between exponential growth from 14 to 42 days of age, and reproductive phenotypes (Pennsylvania). Selection for growth reduced generation interval, days to slaughter age, and increased body weight. Muscle yields and feed conversion improved. Unfortunately, this genetic progress reduced meat quality (muscle texture and flavor) leading to muscle characteristics similar to those of pale-soft-exudative (PSE) in swine (Arkansas). White Plymouth Rock lines divergently selected for 56 day high (HH) and low (LL) body weight have been maintained at the Virginia station (Siegel) for over 40 generations. Prolonged selection has resulted in deviations from a typical chronological timeline for reproductive development. Line HH chickens of the 42nd generation of selection (S(42)) were heavier at 28, 56, 168, and 266 d of age, as well as at sexual maturity than those from line LL of the same generation, and commenced egg production at a younger age (188 d vs. 217 d). Once the LL chickens reached sexual maturity, 99.5% of their ovulations resulted in normal oviposits, in contrast to 94.6% for HH females. In turkeys long term selection for body weight at 16 weeks of age (F-Line) resulted in negative correlations in egg production and resistance to many diseases, while positive correlations were found in egg weight, and breast muscle morphology (Ohio). Studies involving crosses between the selected body weight line and commercial sire lines showed a strong maternal influence present on breast muscle morphology at 16 weeks of age. In Japanese quail, selection for increased body weight at 4 weeks of age was associated with an increase in smooth muscle tumors of the oviduct (Ohio). Long-term selection for egg production in turkeys (E-Line, Ohio) resulted in negative correlations in body and egg weight, and positive correlations in fertility, hatchability, and early poult flip-overs. Broilers divergently selected for high or low incidence of tibial dyschondroplasia (HTD, LTD) were studied to determine differences in intestinal calbindin-28kD mRNA and protein, intestinal vitamin D receptor mRNA, and plasma thyroid hormone (Alabama). Expression of calbindin-28 kD mRNA from HTD chicks fed 5 ¼g vitamin D3 from day of hatch was significantly lower at 4, 8, and 18 days of age than LTD chicks fed the same diet. There was no difference in mRNA expression of vitamin D receptor between HTD and LTD strains due to vitamin D supplementation (5 vs. 40 ¼g/kg diet). Circulating levels of total and free triiodothyronine concentrations were greater among LTD chicks than HTD chicks regardless of dietary vitamin D supplement. White Leghorn hens selected for high or low antibody (HA, LA respectively) response to sheep red blood cell (SRBC) injection have been maintained at the Virginia (Siegel) station for years. Changes in antibody titers to SRBC were monitored in hens divergently selected 24 generations for HA or LA antibody response to SRBC. HA hens had a higher antibody response (12.9 vs. 9.4), but also showed greater persistence in maintaining antibody levels than LA hens. As a result, HA hens exhibited higher antibody titers for the 180-d assay period than LA hens. Ascites resistant, relaxed, and susceptible lines were developed at Arkansas using sire family selection based on mortality data from siblings raised at 2900 m (9,500 feet) in hypobaric chambers. The effect of cold stress on broiler growth data from these lines was measured where birds were brooded at 32 and 30° C (week 1 and 2 respectively). Thereafter birds were reared at 14° C until 6 weeks of age. Six week body weights were not different between susceptible, relaxed, and resistant lines. Improvement in feed conversion and a lower incidence of ascites was found in the resistant line. Incidence of ascites in the resistant line was 1.6% as compared to 18.8 and 12.7% in susceptible and relaxed lines. Susceptible and relaxed lines showed a greater incidence of right ventricle hypertrophy than the resistant line. Additional studies were conducted to determine if mitochondrial electron transport chain (ETC) protein levels were different in resistant and susceptible ascites lines. Previous studies had shown that mitochondrial function was defective in birds with ascites in that oxygen use was less efficient. Several ETC proteins were present at higher levels in resistant birds without pulmonary hypertension syndrome (PHS) than in resistant line birds with PHS or in susceptible birds. One protein was present at higher levels in broilers without PHS than in birds with PHS in both genetic lines. Likewise one protein was present at lower levels in susceptible line birds without PHS than in susceptible birds with PHS, or in resistant line birds regardless of PHS incidence. Results suggest that higher levels of mitochondrial ETC proteins in the right ventricle may be correlated to ascites resistance in broilers. Multiple experiments to facilitate gene discovery and expression through use of expressed sequence tags (ESTs), single nucleotide polymorphisms (SNPs), and comparison of genomic sequences were conducted at the Tuskegee/Virginia (Smith) station. One SNP in every 470 bases was detected in a cDNA chicken library. Seventeen ESTs were mapped on the chicken genetic map, and represented significant resources for genome analysis. Following these studies, a survey of targeted genomic regions of EST sites in broiler and laying hen populations for single nucleotide polymorphisms was conducted (Virginia/Smith). Average heterozygosity within populations were between 0.15 and 0.48 with layers showing the highest heterozygosity. Relative frequency of SNPs in the targeted regions was higher than that reported for other regions scanned in other eukaryotic genomes. Divergent selection for phytate phosphorus bioavailabilty (PPB) among the Athens-Canadian randombred chicken population showed the apparent heritability of the trait to be 0.10 (Georgia). Correlations between PBA, body weight, body weight gain and feed conversion were moderate and indicated that increases in phytate bioavailability would affect growth without affecting feed conversion. Both calcium bioavailability and energy bioavailability were the major factors affecting PPB in males and females. In males, body weight contributed to PPB, but in females nitrogen availability also contributed to PPB. Faster growing birds tended to have a reduced feed retention time as compared to slower growing birds, and therefore utilized phytate phosphorus less. Birds that were able to utilize phytate phosphorus better were also able to release phosphorus for energy utilization, meaning that were better able to utilize energy. Comparative genomic sequences (CGS) were developed to facilitate genetic analysis of guinea fowl, Japanese quail and turkey (Virginia-Smith). CGS sequences were developed using primer pairs specific for reported unique chicken expressed sequence tags (EST). Percentage similarity of CGS was between 81 and 99%, and appeared to be a function of phylogenetic relatedness, and was higher for comparisons between the chicken, quail and turkey than between guinea fowl, chicken, quail and turkey. Much of the effort of the S-289 project focused on nutritional or environmental factors which impact growth, immune response, or reproduction phenotypes. Studies at Alabama, Arkansas, Georgia, Mississippi, South Carolina, two Universities in Tennessee, and Virginia addressed many aspects of nutrition to include fat, energy balance, ascorbic acid, vitamin E, and environmental contaminants. Antibodies against pre-adipocyte formation was studied as a means of reducing fat pad formation in broilers (Texas). The impact of sperm binding on fertility was studied at Pennsylvania. Studies to determine the effects of supplemental phytase on commercial broiler breeder performance were conducted at Alabama. Individually caged hens were fed 0.1or 0.3% available phosphorous and 2 levels of phytase, 0 and 300 phytase units/kg. Phytase increased overall hen-day egg production by 9.8% as compared to hens consuming a low phosphorus diet without phytase. Addition of phytase significantly reduced hen mortality regardless of available phosphorus level. Phytase improved bone mineral content and bone density of hens at both available phosphorus levels. The was no effect on egg weight or specific gravity attributed to phytase, however a negative interaction of phytase and 0.1 % available phosphorus on hatchability was found. Additional efforts at the Georgia station focused on the development of a model to study genotype-nutrition interactions. Because most existing growth models assume mature body weight, and because broilers are slaughtered before they attain mature body weight; most growth models are inappropriate. A modeling system was developed to analyze growth when data is truncated before attaining mature body weight, and has been used to determine how these models behave under different protein levels. At Mississippi, studies were conducted to determine effects of fat source on broiler breeders and their offspring. Broiler breeder performance was affected differently by both level and fat source varying in degree of saturation and linoleic acid content. Broiler chicks from fat fed hens at 35 and 51 wk performed best during growout, and supplemental corn oil in breeder hen diets improved subsequent 0 to 21 d body weight (BW) gain of broilers more efficiently than did supplemental poultry fat. Additional studies at Mississippi studied the effects of gluconeogenic supplementation, and blood parameters on early chick growth and survival. Gluconeogenic supplementation (GS) of broilers via injection at day of hatch facilitated early survivability and growth in chicks from immature breeder hens during the early transition from fat to carbohydrate-based nutrient uptake. Additional studies with young chicks studied the relationship between blood parameters, body weight (BW), and rectal temperature from 29-week old breeder hens. The relationship between rectal temperature and plasma refractive index at hatch and during brooding were opposite. Nevertheless, while chicks experienced increased BW and rectal temperature through 72 hours, dehydration, as indicated by increased refractive index and hematocrit, negatively impacted growth. Plasma refractive index was the only blood parameter that maintained a consistent correlation with BW at hatch and between 24 and 72 hours post-hatch. IL-2, T and B lymphocyte activity of HA and LA chickens was determined in birds from third generation matings of HA and LA lines, and typed for MHC genotypes B13/13, B13/21, and B21/21 (Virginia Siegel). Chickens from both lines carried all the three genotypes B13/13, B13/21, and B21/21. There was no difference in IL-2 like activity between HA and LA lines, however, the LA was significantly higher than HA in T- and B-cell mitogenic activity. The genotype B13/13 had significantly higher IL-2 like activity than the B21/21. The genotype B13/13 was also significantly higher in T- and B-cell mitogenic activity than the B21/21. Results indicate that although the birds were selected for high antibody production to SRBC, lymphocyte mitogenic activity was lower than those selected for low antibody production. Hence, humoral and cell-mediated immune responses appear to be under different genetic controls, and that selection for greater humoral response may be at the expense of cellular responses. These results also suggest differences in IL-2 like activity production between chickens carrying different MHC B-haplotypes, and that genetic control of such activity is possibly linked to the MHC genes. Immunological responses of cockerels fed diets containing either 10 or 300 mg/kg of vitamin E were measured in three commercial broiler nuclear lines representing 2 fast growing lines (A and B), and 1 slow growing line C (Virginia Siegel). Ratio of heterophils to lymphocytes increased, and cutaneous basophil hypersensitivity (CBH) response was depressed by feeding the higher vitamin E diet. For cockerels of Lines A and B, the higher level of vitamin E maintained primary and secondary SRBC antibody levels, whereas for Line C, levels were depressed. The effect of the higher vitamin E diet on IgG and IgM was also stock-dependent. The enhanced heterophil:lymphocyte ratio from feeding vitamin E suggests an improved phagocytic ability of the immune system. Relative asymmetries for toe-web skin thickness (CBH) and shank length were similar for the three lines. Effects of dietary vitamin E on responses to SRBC antigens and Escherichia coli (E. coli) infection were studied in chicks from the HA and LA White Leghorn lines selected for 24 generations. LA chicks were heavier than the HA chicks at 14 d of age and thereafter; and was not affected by vitamin E supplement (10 and 300 mg/kg diet). Antibody titers at 6 and 10 d after inoculation with SRBC were higher in HA than in LA chicks. At 6 and 10 d after inoculation with SRBC, antibody responses were lower in LA chicks fed the diet containing the higher vitamin E concentration than in those fed the diet containing the lower concentration of vitamin E. At 64 d of age, chicks were injected in the posterior thoracic air sac with 0.1 mL of 10(-2) or 10(-4) dilution of E. coli and scored for pericardial and air sac lesions. The HA chicks were more susceptible to E. coli infection than LA chicks as measured by lesion scores and body weight changes. Although dietary vitamin E had no effect on lesion scores in either line, body weight loss at 24 h after E. coli inoculation was significantly reduced in HA chicks fed the higher concentration of vitamin E. The dosage of E. coli had no effect on lesion scores and body weight changes. These results suggest that immune competence in relation to dietary vitamin E response might have been changed by genetic selection, and that optimum dietary vitamin E depends on genotype, among other factors. T-2 mycotoxin is suspected as a causative agent for declining wild bobwhite quail populations in the south (Univ. Tennessee). Pathological analysis of tissues from bobwhite quail dosed with 12, 15, and 18 mg/kg body weight T-2 toxin was conducted, and showed microscopic lesions present in spleen, liver, intestine, kidney, thymus, and bursa of Fabricius. In most tissues, this was characterized by a dose dependent increase in cellular apoptosis (death) characterized by pyknotic and karyorrhexic (non viable) nuclei, and a concurrent increase in lymphocyte infiltration. Lymphoid organs, particularly spleen, showed a dose dependent increase in lymphocyte necrosis and depletion, followed by accumulation of granulocytes and heterophils. Further studies at the Univ. Tennessee sought to determine if dietary antioxidants, or herbal nutriceuticals could be used as protective agents for avian macrophage function in the presence of T-2 toxin. Vitamin E, selenium, ginkgo biloba, and silymarin (milk thistle) were used in in vitro experiments to test their ability to preserve phagocytic function of avian macrophages (HD-11 cells). Phagocytosis of latex beads was significantly less among macrophages incubated with 16 ppm T-2 toxin versus controls. Co-incubation of macrophages with T-2 toxin and vitamin E or selenium did not restore phagocytosis to control levels. However, phagocytosis of macrophages treated with T-2 toxin and 0.1X ginkgo biloba (57.3%) or T-2 toxin and silymarin (62.9%) was not different from controls (62.7% and 67.3% for ginkgo and silymarin trials respectively) indicating that macrophage function was preserved in the presence of T-2 toxin. In turkeys, the effects of a caprine serum fraction (CSF-I2) on mortality and days to death in male and female F-line turkeys (Ohio) infected with Pasteurella multocida were determined (Mississippi). In challenged birds, CSF-I2 significantly reduced percentage mortality in Trial 2 and for both trials combined. Days to death were significantly longer for females in Trial 2 and in both trials combined. Furthermore, in both trials combined, CSF-I2 significantly increased days to death of infected males and decreased percentage mortality of infected females. Although F-line turkeys have become more susceptible to Pasteurella multocida, CSF-I2 conferred resistance to F-line turkeys when challenged with Pasteurella multocida. Timing and duration of feed restriction was studied as a means to reduce the incidence of ascites in broilers (Arkansas). Birds reared in hypobaric chambers simulating 2900 meters (9,500 feet) altitude were compared to birds reared at 390 meters (1,300 feet). Feed restricted broilers (8 hr/day for 6 weeks, 8h/day for 3 weeks followed by full feed, full feed for 3 weeks followed by feed 8 hr/day to 6 weeks of age) were compared against full fed controls to 6 weeks of age. All feed restriction treatments significantly reduced the incidence of ascites when compared to full fed controls. Feed restriction 8 hr/day for the full 6 weeks of the experiment resulted in significantly lighter body weights than all other treatments. Full fed control birds raised at local elevation were heavier than full fed controls raised at 2900 meters. In a companion study at Pennsylvania, it was determined that the incidence of ascitic mortality induced by cold stress was not altered by excess dietary methionine. In humans, familial primary pulmonary hypertension (FPPH) is similar to ascites or pulmonary hypertension syndrome (PHS) in chickens. Mutations in the bone morphogenetic protein receptor type II (BMPR2) have been linked to FPPH in humans. To determine if mutations in the chicken BMPR2 have a similar role in PHS susceptibility, BMRP-II mRNA from ascitic and nonascitic commercial broilers was sequenced and compared to the known White Leghorn sequence (Arkansas). While 12 single nucleotide polymorphisms were identified in the commercial broiler BMPR-II mRNA, no mutations unique to the ascites susceptible broilers were found in the coding, 5 or 3 untranslated regions. Analysis of BMPR2 gene expression as compared to ascitic and non ascitic BMPR-II mRNA expression was not different, and indicated that PHS in broilers was unlikely to be caused by mutations in the BMPR2 gene. South Carolina conducted experiments to determine dietary and non-dietary factors that influence ascorbic acid (AsA) synthesis (as measured by L-gulonolactone oxidase activity) in meat and egg laying strains of chickens, and Japanese quail. In immature broilers, changes in L-gulonolactone oxidase activity (GLO), the final step in biosynthesis, was best characterized by a segmented response function with a maximum value at 13 days followed by a linear decline from day 16. There was no evidence of an early lag period in synthesis. GLO levels were lower in males than females. Food and/or water deprivation up to 24 hrs did not affect GLO in chickens. Food deprivation for 48-72 hours reduced GLO and the response was greater in young birds compared to older birds. Kinetic constants (Km and Vmax) were similar to those reported for rats and similar fast and slow-growing strains of chickens. Strain by age, and diet by age interactions for GLO showed a significantly greater decline in synthetic capacity in commercial broiler strains fed supplemental AsA, than a slow-growing strain. In both strains dietary AsA markedly depressed biosynthesis. Supplemental AsA did not influence egg yield, shell porosity, fertility and hatchability of broiler breeders under field conditions in summer, and did not provide evidence of impaired AsA biosynthesis in newly hatched chicks. Brown egg and white egg strains of layers differed in GLO, but within strain, no differences were found between birds producing strong or weak eggshells. AsA synthesis or tissue concentration was not reduced in strains producing weak shell eggs. Continued studies at South Carolina measured effects of dietary contaminants on ascorbic acid concentration and biosynthesis. Dietary fluoride at 300 mg/kg neither influenced GLO nor depleted AsA in chick tissue. Cadmium and vanadium influenced growth with 50 mg/kg cadmium causing a significant depression in GLO. Oxidative stress induced by dietary iron up to 2000 mg/kg increased GLO synthesis. Ascorbic acid biosynthetic response was measured in response to ACTH infusion or injection, heat stress, dietary hyperthyroidism induced by triiodothyronine. Ascorbic acid biosynthesis was reduced by 60% in birds exposed to continuous ACTH infusion (8 IU/kg BW/day) for 7 days, and resulted in a 500 g loss in body weight, regression of the bursa, and hepatomegaly. Slow-acting ACTH (100g/kg BW/day intramuscularly) given for 3 days doubled plasma corticosterone, but did not decrease GLO. AsA biosynthesis was not reduced in broiler chicks exposed to acute heat stress at 3 weeks of age. Dietary induced hyperthyroidism depressed AsA biosynthesis, and was associated with ascites, but was reduced 10% by supplemental AsA. Antioxidant capacity may be used determine whether supplemental AsA is required. To determine the relationship between dietary antioxidants and AsA synthesis in avians, meat type chickens and mature male Japanese quail were fed diets low or deficient in vitamin E (South Carolina). Iron overload depressed AsA synthesis in chicks fed a practical diet without supplemental selenium and vitamin E. Under these conditions neither hepatic dehydroascorbic acid reductase nor N-acetyl-glucosaminidase was affected. A similar experiment was conducted with Japanese quail fed a corn starch-soy protein purified diet for 10 weeks to ascertain whether vitamin E deficiency up-regulated GLO activity and supplemental vitamin E down-regulated GLO activity. Ascorbic acid synthesis was depressed in birds fed a vitamin E deficient diet, and was further aggravated by the addition of supplemental ascorbic acid. Ascorbic acid biosynthesis increased with the addition of 10 IU vitamin E but down-regulation was not detected as vitamin E supplementation increased to 100 IU/kg. Based on these results there was no evidence of up or down-regulation of GLO in mature Japanese quail fed a vitamin E deficient or supplemented diets. The potential of guinea fowl (Numida meleagris) production for food and profit was studied at Tennessee State University. Studies were conducted to: 1) determine the growth pattern of the pearl grey guinea fowl, and 2) evaluate the dietary crude protein (CP) and metabolizable energy (ME) requirements of French guinea keet broilers. The Richards model was quite robust in estimating the growth pattern of the pearl grey guinea fowl, and estimated the age of maximum growth to be 5.8 weeks of age. Unlike chickens, quail and geese that exhibit sexual dimorphism for growth parameters, the pearl grey guinea fowl did not exhibit differences between sexes. At 0-4 Weeks of Age (WOA), French guinea keet broilers utilized more efficiently diets containing 3100-3150 ME kcal/kg diet and 23% CP; at 5-8 WOA, diets containing 3200 ME kcal/kg diet and 21% CP were efficiently utilized. Eviscerated carcass, breast and drumstick weights were improved in birds fed 3100 and 3150 ME kcal/kg diets and 23 and 25% CP diets. These findings will be utilized to design optimal diets for guinea fowl. The Texas station completed studies designed to reduce fat pad formation in broilers. Adipocyte precursors were obtained from an 18 day old chick embryo to investigate complement mediated cytotoxicity of preadipocytes. In vitro cell cultures of preadipocytes were induced to differentiate through co culture with 10% chicken serum. Administration of specific monoclonal antibodies (MAb) against adipocyte precursor antigens and rabbit complement resulted in a 40-60% reduction in fat cell clusters. Treatment with pools of 2 and 4 Mab decreased the total amount of Mab protein required to reduce fat cell cluster number. Four antibodies alone or in combination reduced fat cell cluster development in a complement dependent manner. Trials to determine if injection of Mab into the allantoic circulation of day 15 embryos would reduce the fat pad of resulting chicks at 42 days of age. High doses of in ovo Mab (0.2 and 0.4 mg) resulted in a significant reduction of abdominal fat pad at 42 days of age which was more than 28% without causing a subsequent reduction in body weight. Fat pad mass reduction occurred without affecting femoral or pectoral fat tissues, body weight, or feed intake. In the area of reproductive physiology, experiments were conducted at Pennsylvania Alabama, Arkansas, and Tennessee. The Pennsylvania station determined that in vitro sperm binding capacity had an additive genetic correlation of 0.75 with fertility. Culling of the 25% lowest roosters based on the sperm binding assay resulted in an increase of 10-25% live chicks produced per rooster. A protein isolated from the supernatant of cyryopreserved rooster sperm increased the capability of sperm to bind in vitro to the perivitelilne membrane, and increase fertility. This protein was named universal primary sperm-egg binding protein (UPSEBP), and is a fragment of prosaposin, which may have broad implications for cause and therapy of subfertility in chickens. Dietary protocols and crude protein levels were addressed as effectors of semen production and concentration of broiler breeders at Alabama. Initiation of skip a day feeding at 0.45 or 0.68 kg body weight were not important in improving semen production, whereas a low, 12 percent crude protein diet fed during the rearing period improved semen volume from 28-36 weeks of age vs. a 16% protein grower diet. Sperm concentration from 28-52 weeks of age was negatively correlated with body weight from 8-20 weeks, and showed that continued body weight gain after sexual maturity was necessary to optimize semen production. In bobwhite quail hens, date of puberty was delayed, by exposure to T-2 toxin during the prepuberal lighting period (Univ. of Tennessee). Overall hen-day egg production, and fertile hatchability of eggs were not affected. Fertility of eggs, egg specific gravity, and total hatchability of eggs was depressed as a result of exposure to T-2 toxin. In males, body weight change, testicular weight, length and diameter were all significantly less among males fed 16 mg/kg T-2 toxin for 28 days as compared to untreated controls. Mouth lesion scores were higher among birds fed 8 or 16 mg/kg T-2 toxin. Testicular melanin pigmentation, an indication of lack of spermatogenesis, increased among all birds fed T-2 toxin. Examination of histological samples showed a dose dependent increase in cellular destruction, and a decrease in spermatogenesis. Ultrasonography was used to characterize the ovarian status of chickens as a means to evaluate ovarian status noninvasively (Arkansas). Ultrasound images were used to determine the number and diameter of the large yellow follicles > 10 mm, as well as the presence of an egg in the oviduct. Ultrasound images were able to predict the number of large yellow follicles +/- 1 with 93.3- 96.3% accuracy. Diameter size of follicles was determined with 77.8 % accuracy. All regressed and regressing ovaries were correctly determined via ultrasound. The breadth and diversity of the S-289 members is readily seen from the station summaries above. Use of selected genetic lines and commercial stock to address principal concerns of the poultry industry, and to reveal genomes of economically important traits have all been goals of this group. It is the purpose of this project to continue to develop genetic, nutritional, and managerial protocols to improve growth, immune competence, and reproductive performance of traditional and non traditional poultry stocks.

Publications

Books Written or Edited: W. H. Muir and S. E. Aggrey, Editors. 2003. Poultry Genetics, Breeding and Biotechnology. CABI, U.K. 744pp. Book Chapters: Kuhnlein, U., S.E. Aggrey and D. Zadworny, 2003. Progress and prospects in resistance to diseases. Pg 283-292, In: Poultry Genetics, Breeding and Biotechnology, (W.H. Muir and S.E. Aggrey, Eds.) CABI, U.K. Kuhnlein, U., S.E. Aggrey, N. Kansaku and D. Zadworny, 2003. DNA polymorphism in functional genes. Pg 647-664, In: Poultry Genetics, Breeding and Biotechnology, (W.H. Muir and S.E. Aggrey, Eds.) CABI, U.K. Aggrey, S.E. and R. Okimoto, 2003. DNA marker technology: development, usage and application. Pg 419-438, In: Poultry Genetics, Breeding and Biotechnology, (W.H. Muir and S.E. Aggrey, Eds) ,CABI, U.K. Refereed journal articles: Acar, N., P.H. Patterson, and G.F. Barbato, 2001. 1. Appetite suppressant activity of supplemental dietary amino acids and subsequent compensatory growth of broilers. Poultry Sci. 80(8): 1215-1222. Acar, N., G.F. Barbato, and P.H. Patterson, 2001. 2. The effect of feeding excess methionine on live performance, carcass traits , and ascitic mortality. Poultry Sci. 80(11): 1589-1589. Aggrey, S. E., 2002. Comparison of three non-linear and spline regression models for describing chicken growth curves. Poultry Sci. 81:1782-1788. Aggrey, S. E., 2003. Dynamics of relative growth in Japanese quail lines divergently selected for early growth and their control. Growth, Dev. and Aging 67:47-54. Aggrey, S. E., 2004. Modeling the effect of nutritional status on pre-asymptotic- and relative growth- rates in a randombred chicken population. J. An. Breed. Gen. 121: 260-268 Aggrey, S. E. and H. L. Marks, 2002. Analysis of censored survival data in Japanese quail divergently selected for growth and their control. Poultry Sci. 81: 1618-1620. Aggrey, S. E., G. A. Ankra-Badu, and H. L. Marks, 2003. Effect of long-term divergent selection on growth characteristics in Japanese quail. Poultry Sci. 82:538-542. Ankra-Badu, G. A., S. E. Aggrey, G.M. Pesti, R.I. Bakalli, W. Zhang and H.M. Edwards, Jr., 2004. Modeling of parameters affecting phytate phosphorus utilization in growing birds. Poultry Sci. 83:1083-1088. Anthony, N. B., K. E. Nestor, D. A. Emmerson, Y. M. Saif, R. Vasilatos-Younken, and W. L. Bacon, 1999. Effect of feed withdrawal or challenge with Pasteurella multocida on growth, blood metabolites, circulating growth hormone, and insulin-like growth factor-I concentrations in eight-week old turkeys. Poultry Sci. 78:1268-1274. Anthony, N.B., K.E. Nestor, D.A. Emmerson, M.E. Emara, Y.M. Saif, R. Vasilator-Younken, and W.L. Bacon, 1999. Effect of Feed Withdrawal or challenge with Pasteurella multocida on growth, blood metabolites, circulating growth hormone, and insulin-like growth factor-I concentrations in eight-week-old turkeys. Poultry Sci. 77:1268-1274. Balog, J.M., Anthony, N.B., Cooper, M.A., Kidd, B.D., Huff, G.R., Huff, W.E. and Rath, N.C., 2000. Ascites syndrome and related pathologies in feed restricted broilers raised in a hypobaric chamber. Poultry Sci. 79:318-323. Balog, J.M., B.D. Kidd, N.B., Anthony, G.R. Huff, W.E. Huff, N.C. Rath, 2003. Effect of cold stress on broilers selected for resistance or susceptibility to ascites syndrome. Poultry Sci. 81:1383-1387. Barbato, G.F., 1999. Genetic relationships between selection for growth and reproductive effectiveness, Poultry Sci. 78(3): 444-452. Berry, W.D., 2003. The physiology of induced molting. Poultry Sci. 82(6):971-980. Berry, W.D., J.B. Hess, R.J. Lien, and D.A. Roland, 2003. Egg production, fertility and hatchability of breeder hens receiving dietary phytase. J. Appl. Poultry Res. 12(3):264-270. Boa-Amponsem, K., E. A. Dunnington, K. S. Baker, and P. B. Siegel, 1999. Diet and immunological memory of lines of White Leghorn chickens divergently selected for antibody response to sheep red blood cells. Poultry Sci. 78:165-170. Boa-Amponsem, K., C. T. Larsen, E. A. Dunnington, and P. B. Siegel, 1999. Immunocompetence and resistance to marble spleen disease of broiler- and layer-type pure lines of chickens. Avian Pathol. 28:379-384. Boa-Amponsem, K., E. A. Dunnington, F. W. Pierson, C. T. Larsen, and P. B. Siegel, 2000. Antibody responses to different dosages of sheep red blood cells in lines of chickens selected for high and low antibody response to sheep red blood cells. Poultry Sci. 79:159-162. Boa-Amponsem, K., S.E.H. Price, E. A. Dunnington, and P. B. Siegel, 2001. Effect of route of inoculation on humoral immune response of White Leghorn chickens selected for high or low antibody response to sheep red blood cells. Poultry Sci. 80:1073-1078 Bruzual, J. J., S. D. Peak, J. Brake, and E. D. Peebles, 2000. Effects of relative humidity during incubation on hatchability and body weight of broiler chicks from young breeder flocks. Poultry Sci. 79:827-830. Bruzual, J. J., S. D. Peak, J. Brake, and E. D. Peebles, 2000. Effects of relative humidity during the last five days of incubation and brooding temperature on performance of broiler chicks from young broiler breeders. Poultry Sci. 79:1385-1391. Burnham, M. R., E. David Peebles, C. W. Gardner, J. Brake, J. J. Bruzual, and Patrick D. Gerard, 2001. Effects of incubator humidity and hen age on yolk composition in broiler hatching eggs from young breeders. Poultry Sci. 80:1444-1450. Burt, D.W., D.R. Morrice, A. Sewalem, J. Smith, I.R. Patton, E.J. Smith, J. Bentley, P.M. Hocking, 2003. Preliminary linkage map of the turkey (Meleagris gallopavo) based on microsatellite markers. Anim. Genet. 34(6):399-409. Chen, S.-E., D. W. Long, K. E. Nestor, R. L. Walzem, V. L. Meuniot, H. Zhu, R. J. Hansen, and W. L. Bacon, 1999. Effect of divergent selection for total plasma phosphorus on plasma and yolk very low density lipoproteins and plasma concentrations of selected hormones in laying Japanese quail. Poultry Sci. 78:1241-1251. Christensen, V. L., W. E. Donaldson, K. E. Nestor, and J. P. McMurtry, 1999. Effect of genetics and maternal dietary iodide supplementation on turkey embryonic growth. Poultry Sci. 78:883-889. Christensen, V. L., W. E. Donaldson, K. E. Nestor, and J. P. McMurtry, 1999. Effect of genetics and maternal dietary iodide supplementation on glycogen content of organs within embryonic turkeys. Poultry Sci. 78:890-898. Christensen, V. L., W. E. Donaldson, and K. E. Nestor, 1999. Length of the plateau and pipping stages of incubation affects the physiology and survival of turkeys. Br. Poult. Sci. 40:297-303. Christensen, V. L., W. E. Donaldson, and K. E. Nestor, 1999. Effect of supplemental oxygen on blood plasma organic acids within embryos from selected lines of turkeys. Poultry Sci. 78:1601-1605. Christensen, V. L., J. P. McMurtry, W. E. Donaldson, and K. E. Nestor, 1999. Supplemental oxygen affects plasma insulin-like growth factors in embryos from selected lines of turkeys. Poultry Sci. 78:1606-1610. Christensen, V. L., D. O. Noble, and K. E. Nestor, 2000. Influence of selection for increased body weight, egg production, and shank width on the length of the incubation period of turkeys. Poultry Sci. 79:613-618. Christensen, V. L., J. P. McMurtry, W. E. Donaldson, and K. E. Nestor, 2001. Incubation temperature affects plasma insulin-like growth factors in embryos from selected lines of turkeys. Poultry Sci. 80:949-954. Christensen, V. L., G. S. Davis, and K. E. Nestor, 2002. Environmental incubation factors influence embryonic thyroid hormones. Poultry Sci. 81:442-450. Cisar, C.R., J.M. Balog, N.B. Anthony, A.M. Donoghue, 2003. Sequence analysis of bone morphogenetic protein receptor type II mRNAs from ascitic and non-ascitic commercial broilers. Poultry Sci. 81:1494-1499. Cisar, C. R., J. M. Balog, R. Okimoto, N. B. Anthony, and A. M. Donoghue, 2003. The chicken bone morphogenetic protein receptor type II (BMPR2) gene maps to chromosome 7. Animal Genetics 34:475-476. Cisar, C.R., J.M. Balog, N.B. Anthony, M. Iqbal, W.G. Bottje, and A.M. Donoghue, 2004. Differential expression of mitochondrial electron transport chain proteins in cardiac tissues of broilers from pulmonary hypertension syndrome resistant and susceptible lines. Poultry Sci. 83(8):1420-1426. Cogburn, L.A. X. Wang, W. Carre, T. E. Potter, S. E. Aggrey and J. Simon, 2003. System-wide chicken DNA chip, gene expression profiling and discovery of functional genes. Poultry Sci. 82:939-951. Cogburn, L. A., X. Wang, W. Carre, L. Rejto, S. E. Aggrey, M. Duclos, J. Simon and T. E. Porter, 2004. Functional genomics in chickens: Development of integrated systems microarrays for transcriptional profiling and discovery regulatory genes, 2004. Comp. Funct. Gen. 5: 253-261. Creel, L.H., D.V. Maurice, S.F. Lightsey, and L.W. Grimes, 2001. Stability of dietary ascorbic acid and the effect of supplementation on reproductive performance of broiler breeder chickens. Brit. Poultry Sci. 42: 96-102. Croom, W. J., Jr., J. Brake, B. A. Coles, V. L. Christensen, G. B. Havenstein, B. W. McBride, E. D. Peebles, and I. L. Taylor, 1999. Is intestinal absorption capacity rate-limiting for performance in poultry? J. Appl. Poult. Res. 8(2):242-252. Ding, S. T., Y. C. Li, K. E. Nestor, S. G. Velleman, and H. J. Mersmann, 2003. Expression of turkey transcription factors and acyl-coenzyme oxidase in different tissues and genetic populations. Poultry Sci. 82:17-24. Emmerson, D. A., S. G. Velleman, and K. E. Nestor, 2002. Genetics of growth and reproduction in the turkey. 15. Effect of long-term selection for increased egg production on the genetics of growth and egg production traits. Poultry Sci. 81:316-320. Gehad, A. E., M. M. Mashaly, H. S. Siegel, E. A. Dunnington, and P. B. Siegel, 1999. Effect of genetic selection and MHC haplotypes on lymphocyte proliferation and Interleukin-2 activity in chicken lines selected for high and low antibody production against sheep red blood cells. Vet. Immunol. & Immunopath. 68:13-24. Grizzle, Judith M. D. B. Kersten, M. D. McCracken, A. E. Houston, and A. M. Saxton. 2004. Determination of the acute 50% lethal dose (LD50) T-2 Toxin in adult bobwhite quail: additional studies on blood chemistry and the morphology of internal organs. Avian Dis. 48(2):392-399. Gross, W. B., P. B. Siegel, and F. W. Pierson, 2002. Effects of genetic selection for high or low antibody response on resistance to a variety of disease challenges and the relationship of resource allocation. Avian Dis. 46:1007-1010. Hammerstedt, R.H., P.G. Cramer, G.F. Barbato, R.P. Amann, J.S. OBrien, and M.D. Griswold, 2001. A fragment of prosaposin (SGP-1) from rooster sperm promotes sperm-egg binding and improves fertility in chickens. J. Androl. 22(3): 361-375. Hall, L.E., R.B. Shirley, R.I. Bakalli, S. E. Aggrey, G. M. Pesti and H.M. Edwards, Jr. 2003. Power of two methods for estimation of bone ash in broilers. Poultry Sci. 82:414-418. Hooper, C.L., D.V. Maurice, S.F. Lightsey, and J.E. Toler, 2000. Factors affecting ascorbic acid biosynthesis in chickens. I. Adaptation of an assay and the effect of age, sex and food deprivation. J. Anim. Physiol. Anim. Nutr. 84: 48-56. Hooper, C.L., D.V. Maurice, S.F. Lightsey, and J.E. Toler, 2000. Factors affecting ascorbic acid (AsA) biosynthesis in chickens. II. Effect of dietary AsA and strain of chicken. J. Anim. Physiol. Anim. Nutr. 86: 326-332. Huang, H.B., Y.Q. Song, M. Hsei, R. Zahorchak, J. Chiu, C. Teuscher, and E.J. Smith, 1999. Development and characterization of genetic mapping resources for the turkey (Meleagris gallopavo). J. Hered. 90(1):240-242. Keirs, Robert W., E. David Peebles, Sue Ann Hubbard, and Sharon K. Whitmarsh, 2002. Effects of supportive gluconeogenic substances on the early performance of broilers under adequate brooding conditions. J. Appl. Poult. Res. 11:367-372. Keirs, Robert W., E. David Peebles, and Patrick D. Gerard 2004. Systematic documentation of embryonic anomalies of broilers and their increased incidence in Mississippi. J. Appl. Poult. Res. 13(3):481-487. Keirs, R. W., E. D. Peebles, S. K. Whitmarsh, and P. D. Gerard, 2004. Associations of increased late embryo loss with incidences of anomalies and head disorientation toward the small end in broiler hatching eggs. Avian Poult. Biol. Rev.14:232-233. Kidd, M. T., E. D. Peebles, S. K. Whitmarsh, J. B. Yeatman, and R. F. Wideman, Jr., 2001. Growth and immunity of broiler chicks as affected by dietary arginine. Poultry Sci. 80:1535-1542. Kirby, Y.K., N.B. Anthony, J.D. Hughes, Jr., R.W. McNew, J.D. Kirby, and R.F. Wideman, Jr., 1999. Electrocardiographic and genetic evaluation of Giant Jungle fowl, broilers, and their reciprocal crosses following unilateral bronchus occlusion. Poultry Sci. 78:125-134. Kirby, Y.K., R.W. McNew, N.B. Anthony, J.D. Kirby, N.E. Marson, J.D. Hughes, Jr., and R.F. Wideman, Jr., 1999. Electrocardiographic evaluation of broilers following unilateral occlusion of an extrapulmonary primary bronchus. Poultry Sci. 78:242-254. Kuhnlein, U, R. Prasanejad, D. Zadworny, and S. E. Aggrey, 2003. Dynamics of genotype-phenotype in trait association. Poultry Sci. 82:876-881. Kuo, A. Y., J. C. Lee, P. B. Siegel, and D. M. Denbow, 2001. Differential cardiovascular effects of pharmacological agents in chickens selected for high and low body weight. Physiol. & Behav. 74:573-579. Latour, M. A., E. David Peebles, S. M. Doyle, and T. Pansky, 2001. Effects of broiler breeder hen age and dietary fat intake on circulating serum lipids. J. Appl. Anim. Res.19:73-84. Lee, J.T., C.A. Bailey, and A.L. Cartwright, 2003. Guar meal germ and hull fractions differently affect growth performance and intestinal viscosity of broiler chickens. Poultry Sci. 82(10):1589-1595. Lee, J.T., C.A. Bailey, and A.L. Cartwright, 2003. Beta mannanase ameliorates viscosity associated depression of growth in broiler chickens fed guar germ and hull fractions. Poultry Sci. 82(12):1925-1931. Li, Z., K. E. Nestor, Y. M. Saif, W. L. Bacon, and J. W. Anderson, 1999. Effect of selection for increased body weight on mitogenic responses in turkeys. Poultry Sci. 78:1532-1535. Li, Z., K. E. Nestor, Y. M. Saif, Z. Fan, M. Luhtala, and O. Vainio, 1999. Cross-reactive anti-chicken CD4 and CD8 monoclonal antibodies suggest polymorphism of the turkey CD8" molecule. Poultry Sci. 78:1526-1531. Li, Z., K. E. Nestor, Y. M. Saif, J. W. Anderson, and R. A. Patterson, 2000. Serum immunoglobulin D and M concentrations did not appear to be associated with resistance to Pasteurella multocida in a large-bodied turkey line and a randombred control population. Poultry Sci. 79:163-166. Li, Z., K. E. Nestor, Y. M. Saif, and M. Luhtala, 2000. Flow cytometric analysis of T lymphocyte subpopulations in large-bodied turkey lines and a randombred control population. Poultry Sci. 79:219-223. Li, Z., K. E. Nestor, Y. M. Saif, and J. W. Anderson, 2000. Antibody responses to sheep red blood cell and Brucella abortus antigens in a turkey line selected for increased body weight and its randombred control. Poultry Sci. 79:804-809. Li, Z., K. E. Nestor, Y. M. Saif, J. W. Anderson, and R. A. Patterson, 2001. Effect of selection for increased body weight in turkeys on lymphoid organ weights, phagocytosis, and antibody responses to fowl cholera and Newcastle disease-inactivated vaccines. Poultry Sci. 80:689-694. Liu, H.-K., K. E. Nestor, D. W. Long, and W. L. Bacon, 2001. Frequency of luteinizing hormone surges and egg production rate in turkey hens. Biol. Reprod. 64:1769-1775. Liu, X., K. E. Nestor, D. C. McFarland, and S. G. Velleman, 2002. Developmental expression of skeletal muscle heparan sulfate proteoglycans in turkeys with different growth rates. Poultry Sci. 81:1621-1628. Liu, X., D. C. McFarland, K. E. Nestor, and S. G. Velleman, 2003. Expression of fibroblast growth factor 2 and its receptor during muscle development from turkeys with different growth rates. Dom. Anim. Endocrinol. 25:215-229. Liu, X., D. C. McFarland, K. E. Nestor, and S. G. Velleman, 2004. Developmental regulated expression of syndecan-1 and glypican in pectoralis major muscle in turkeys with different growth rates. Dev. Growth Differ. 46:37-51. Liu, X., K. E. Nestor, and S. G. Velleman, 2004. The influence of selection for increased body weight and sex on pectoralis major muscle weight during the embryonic and posthatch periods. Poultry Sci. 83:1089-1092. Maurice, D.V., S.F. Lightsey, A. Abudabos, and J.E. Toler, 2000. Factors affecting ascorbic acid biosynthesis in chickens. III. Effect of dietary fluoride on L-gulonolactone oxidase activity and tissue ascorbic acid concentration. J. Anim. Physiol. Anim. Nutr. 86: 383-388. Maurice, D.V., S.F. Lightsey, and J.E. Toler, 2004. Ascorbic acid biosynthesis in hens producing strong and weak eggshells. Brit. Poultry Sci. 45:404-408. Maurice, D.V., S.F. Lightsey, and J.E. Toler, 2004. Factors affecting ascorbic acid biosynthesis in chickens. IV. Effect of cadmium and vanadium on L-gulonolactone oxidase activity and tissue ascorbic acid concentration. J. Anim. Physiol. Anim. Nutr. 88:427-433. Melnychuk, V.L., M.A. Cooper, J.D. Kirby, R.W. Rorie, and N.B. Anthony, 2002. Use of ultrasonography to characterize ovarian status in chickens. Poultry Sci. 81:892-895. Melnychuk, V.L., J.DZ. Kirby, Y.K. Kirby, D.A. Emmerson, and N.B. Anthony, 2004. Effect of strain, feed allocation program, and age at photostimulation on reproductive development and carcass characteristics of broiler breeder hens. Poultry Sci. 83(11):1861-1867. Nahashon, S. N., J. Bartlett, G. R. McDaniel, and E. J. Smith. 2000. Inheritance of tibial dyschondroplasia in a Single Comb White Leghorn strain cross. T. Horizons 11:26-27. Nahashon, S. N., C. O. Briles, S. Louis and J. R. Bartlett, 2000. Performance and adipose cellularity of female progeny of White Plymouth Rock dams and Commercial Broiler Breeder Sires. J. Animal and Feed Science 9:379-389. Nahashon, S.N., J. Bartelett, and E.J. Smith, 2004. Effect of the late feathering or early feathering genotypes on performance and carcass traits of broiler chickens. Livestock Prod. Sci. 91(1-2)83-94. Nestor, K. E., Y. M. Saif, J. W. Anderson, R. A. Patterson, and Z. Li, 1999. Variation in resistance to Pasteurella multocida among turkey lines. Poultry Sci. 78:1377-1379. Nestor, K. E., M. S. Lilburn, Y. M. Saif, J. W. Anderson, R. A. Patterson, Z. Li, and J. E. Nixon, 1999. Influence of body weight restriction in a body-weight-selected line of turkeys on response to challenge with Pasteurella multocida. Poultry Sci. 78:1263-1267. Nestor, K. E., J. W. Anderson, and R. A. Patterson, 2000. Effects of selection for increased body weight, egg production, and shank width on developmental stability in turkeys. Poultry Sci. 79:937-945. Nestor, K. E., J. W. Anderson, and R. A. Patterson, 2000. Genetics of growth and reproduction in the turkey. 14. Changes in genetic parameters over thirty generations of selection for increased body weight. Poultry Sci. 79:445-452. Nestor, K. E., J. W. Anderson, and S. G. Velleman, 2001. Genetic variation in pure lines and crosses of large-bodied turkey lines. 1. Body weight, walking ability, and body measurements of live birds. Poultry Sci. 80:1087-1092. Nestor, K. E., J. W. Anderson, and S. G. Velleman, 2001. Genetic variation in pure lines and crosses of large-bodied turkey lines. 2. Carcass traits and body shape. Poultry Sci. 80:1093-1104. Nestor, K. E., W. L. Bacon, S. G. Velleman, J. W. Anderson, and R. A. Patterson, 2002. Effect of selection for increased body weight and increased plasma yolk precursor on developmental stability in Japanese quail. Poultry Sci. 81:160-168. Nestor, K. E., J. W. Anderson, R. A. Patterson, and S. G. Velleman, 2004. Genetic variation in body weight and egg production in an experimental line selected long term for increased egg production, a commercial dam line, and reciprocal crosses between lines. Poultry Sci. 83:1055-1059. Noble, D. O., K. E. Nestor, and C. R. Polly, 1999. Factors influencing early poult flip-overs in experimental populations of turkeys. Poultry Sci. 78:178-181. Pavlidis, H. O., S. E. Price, and P. B. Siegel, 2002. Associations between egg production and clutch length in four selected lines of chickens. J. Appl. Poult. Res. 11:204-307. Peebles, E. David, Steven M. Doyle, Tomas Pansky, Patrick D. Gerard, Mickey A. Latour, Carolyn R. Boyle, and Tom W. Smith, 1999. Effects of breeder age and dietary fat on subsequent broiler performance. 1. Growth, mortality, and feed conversion. Poultry Sci. 78:505-511. Peebles, E. David, Steven M. Doyle, Tomas Pansky, Patrick D. Gerard, Mickey A. Latour, Carolyn R. Boyle, and Tom W. Smith, 1999. Effects of breeder age and dietary fat on subsequent broiler performance. 2. Slaughter yield. Poultry Sci. 78:512-515. Peebles, E. David, Lumu Li, Sherman L. Miller, Tomas Pansky, Sharon Whitmarsh, Mickey A. Latour, and Patrick D. Gerard, 1999. Embryo and yolk compositional relationships in broiler hatching eggs during incubation. Poultry Sci. 78:1435-1442. Peebles, E. David, C. D. Zumwalt, Steven M. Doyle, Patrick D. Gerard, Mickey A. Latour, Carolyn R. Boyle, and Tom W. Smith, 2000. Effects of dietary fat type and level on broiler breeder performance. Poultry Sci. 79:629-639. Awarded as the publication with the most relevance and potential impact to Mississippi Agriculture by the Mississippi Agricultural and Forestry Experiment Station (2000). Peebles, E. David, C. D. Zumwalt, Steven M. Doyle, Patrick D. Gerard, Mickey A. Latour, Carolyn R. Boyle, and Tom W. Smith, 2000. Effects of breeder age and dietary fat source and level on broiler hatching egg characteristics. Poultry Sci. 79:698-704. Peebles, E. David, C. W. Gardner, J. Brake, C. E. Benton, J. J. Bruzual, and Patrick D.Gerard, 2000. Albumen height and yolk and embryo compositions in broiler hatching eggs during incubation. Poultry Sci. 79:1373-1377. Peebles, E. David, Steven M. Doyle, C. D. Zumwalt, Patrick D. Gerard, Mickey A. Latour, Carolyn R. Boyle, and Tom W. Smith, 2001. Breeder age influences embryogenesis in broiler hatching eggs. Poultry Sci. 80:272-277. Peebles, E. David, M. R. Burnham, C. W. Gardner, J. Brake, J. J. Bruzual, and P.D. Gerard, 2001. Effects of incubational humidity and hen age on embryo composition in broiler hatching eggs from young breeders. Poultry Sci. 80:1299-1304. Peebles, E. David, J. Croom, W. R. Maslin, S. K. Whitmarsh, L. R. Daniel, and I. L. Taylor, 2001. In ovo peptide YY and epidermal growth factor administration and their effects on growth and yolk utilization in neonatal meat-type chickens (Gallus domesticus). Comp. Biochem. Physiol., Part A, 130(4):741-749. Peebles, E. D., C. D. Zumwalt, P. D. Gerard, M. A. Latour, and T. W. Smith, 2002. Market age live weight, carcass yield, and liver characteristics of broiler offspring from breeder hens fed diets differing in fat and energy contents. Poultry Sci. 81:23-29. Peebles, E. David, C. D. Zumwalt, T.W. Smith, P.D. Gerard, and M. A. Latour, 2002. Poultry fat and corn oil may be used to adjust energy in the diets of young breeder hens without affecting embryogenesis and subsequent broiler growout performance. J. Appl. Poult. Res. 11:146-154. Peebles, E. David., M. R. Burnham, R. L. Walzem, S. L. Branton, and P. D. Gerard, 2004. Effects of fasting on serum lipids and lipoprotein profiles in the egg-laying hen (Gallus domesticus). Comp. Biochem. Physiol., Part A. 138(3):305-311. Peebles, E. D., R. W. Keirs, L. W. Bennett, T. S. Cummings, S. K. Whitmarsh, and P. D. Gerard, 2004. Relationships among post-hatch physiological parameters in broiler chicks hatched from young breeder hens and subjected to delayed brooding placement. Int. J. Poultry Sci. 3(9):578-585. Peebles, E. D., R. W. Keirs, L. W. Bennett, S. K. Whitmarsh, and P. D. Gerard, 2004. Egg weight loss during incubation and relative hatching chick weight and their relationships to post-hatch blood glucose concentration, body temperature, visceral changes, and liver glycogen concentrations in nutrient restricted broilers. Avian Poult. Biol. Rev15:228-230. Picard, M., P. B. Siegel, C. Leterrier, and P. A. Geraert, 1999. 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Increased mortality in turkeys selected for increase body weight following vaccination with a live Newcastle disease virus vaccine. Avian Dis. 46:505-598. Shi, L. P. Drummond, S. De Kloet, G.E. Pimentel-Smith, and E.J. Smith, 2000. Comparative DNA sequence analysis of genetic variation in the African grey parrot, Psittacus erythacus. Genetica 110(3):227-230. Shi, L., G.E. Smith, and E.J. Smith, 2001. Linkage assignment of two novel expressed sequence tagged sites in the chicken. Animal Genetics 32(1):49-50. Shirley, R.B., A.J. Davis, M.M. Compton, and W.D. Berry, 2003. The expression of calbindin in chicks that are divergently selected for low or high incidence of tibial dyschondroplasia. Poultry Sci. 82(12):1965-1973. Siegel, P. B., 2002. Body weight, obesity, and reproduction in meat-type chickens. Poultry & Avian Biol. Rev. 13:209-213. Siegel, P. B. and J. H. Wolford, 2003. A review of some results of selection for juvenile body weight in chickens. J. Poultry Sci. 40:81-91. 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Impact Statements

Genetic selection for improved growth rates in chickens and turkeys reduced days to market age, but was negatively correlated with meat quality and reproduction. In chickens, fertility was positively correlated with growth to 14 days of age but negatively correlated with growth to 42 days of age. In turkeys selection for 16 week body weight resulted in negative correlations in egg production and resistance to disease, but positive correlations with egg weight, and breast muscle morphology.
The incidence of ascites, or pulmonary hypertension syndrome, a fatal disease of young birds was reduced by selection for resistance. Ascites resistant lines showed a positive correlation with feed conversion and a 17 percentage point reduction in ascites as compared to susceptible lines. Lines susceptible to ascites showed a greater incidence of right ventricle hypertrophy, however feed restriction was found to reduce the incidence of ascites as compared to conventional full fed controls.
Methods to facilitate gene discovery in chickens showed that the chicken genome contains 1 single nucleotide polymorphism (SNP) in every 470 DNA bases. Using SNPs to analyze targeted genomic regions, it was found that the heterozygosity between broilers and laying hens was between 0.15 and 0.48. Laying hens were determined to have the level of heterozygosity of genes, and therefore greater genetic variation as compared to broiler chickens.
Divergent selection for phytate phosphorus bioavailablity (PBA) in chickens to reduce organic phosphorus dependency showed the trait heritability was low, 0.10. PBA was affected by calcium and energy availability, and faster growing birds were less able to utilize phytate phosphorus. To counteract the low heritability of PBA, it was found that use of dietary phytase to increase phytate digestion, and reduce organic phosphorus dependency was successful in breeder birds.
Among strains of laying hens selected for high antibody response to sheep red blood cell injection, lymphocyte mitogenic activity was lower than those selected for low antibody production. Hence, humoral and cell-mediated immune responses appear to be under different genetic controls, and that selection for greater humoral response may be at the expense of cellular responses.
In modern strains of broiler breeder chickens, supplementing breeder diets with corn oil as compared to poultry fat improved 0-21 day body weight gain of broiler offspring. Reduced growth affected by dehydration during the first 72 hours post hatch in chickens was best predicted by reduced blood plasma refractive index and hematocrit.
Dietary antioxidants were found to have positive effects in avian species. Vitamin E protected hens selected for high antibody production against sheep red blood cell injection, and exposed to Escherichia coli infection. Ascorbic acid decreased the incidence of ascites induced by dietary hyperthyroidism. However, stress as induced by adrenocorticotropic hormone, caused a 60% reduction in ascorbic acid biosynthetic activity.
The guinea fowl was found to be a potential avian meat source. Optimal growth age was competitive with broiler chickens at 5.8 weeks of age and did not show sexual dimorphism as exhibited in chickens.
Injection of 15 day chick embryos with monoclonal antibodies against fat cell precursors resulted in fat pad formation of resulting chicks at 42 days of age. Fat pad reduction occurred without affecting body weight or feed intake. Use of antibodies against fat cell precursors may be a means to reduce fat pad formation in broiler chickens.
Bobwhite quail populations, in decline for 30 years may be negatively affected by fungal contamination of food sources. Specifically, T-2 toxin a contaminate of grain sources during cool wet seasons decreased fertility, spermatogenesis, hatchability, growth and livability of quail. Antioxidant herbs, ginkgo or silymarin were found to protect avian macrophage cells against T-2 toxin.
In broiler breeder chickens, sperm concentration was negatively correlated with body weight from 8-20 weeks of age, and showed that continued body weight gain after sexual maturity was necessary to optimize semen production. Sperm binding capacity was found to have an additive genetic correlation of 0.75 with fertility. A protein isolated from rooster sperm and found to increase sperm binding was identified as a fragment of prosaposin.