Genotype‐environment interactions in genetically diverse meat‐type stocks of Chickens¹

This investigation was conducted as part of the Southern Regional Poultry Breeding Project (S‐68), a cooperative study involving agricultural experiment stations in the Southern Region and supported in part by Regional Research Funds and Poultry Research Branch Funds of the United States Department of Agriculture.

Synopsis

Six experimental stocks were evaluated in two trials at seven locations to determine if genetically diverse meat‐type stocks would be useful in identifying specific causes of genotype‐environment interactions.

Stock differences in body weights (at 1, 5 and 8 weeks) were significant and responsible for 55 to 80% of the total phenotypic variation. Location effects were also significant, while trial effects were significant only at 1 and 5 weeks of age. Stock‐location interactions were significant (P < 0.01) for body weight at 1 and 5 weeks of age in both sexes while male 8‐week body weight and shank length differences were also significant (P< 0.05). The importance of stock‐location interactions for juvenile body weight decreased with age, being reponsible for 3% of the total phenotypic variation at 1 week and less than 1 % at 8 weeks of age.

These data support previous reports indicating stock‐location interactions are of minor importance for juvenile body weights in broiler stocks and responsible for less than 2% of the total phenotypic variation in 8‐week body weight. Utilisation of genetically diverse stocks did not materially increase the importance of or aid in identifying these interactions.

Notes

This investigation was conducted as part of the Southern Regional Poultry Breeding Project (S‐68), a cooperative study involving agricultural experiment stations in the Southern Region and supported in part by Regional Research Funds and Poultry Research Branch Funds of the United States Department of Agriculture.

Coordinator, Southern Regional Poultry Breeding Project, ASR, ARS, USD A, Athens, Georgia 30601.

Technical Committee Members (S‐68) from the Agricultural Experiment Stations located in Alabama, Arkansas, Louisiana, Mississippi, North Carolina, Texas and Virginia, respectively.