Chicken breeding study reveals limits of selecting for extreme body weight
Researchers crossed chickens bred for decades to be either very large or very small, expecting offspring to show intermediate traits. Instead, the crossbreds displayed unexpected genetic effects that could reshape how poultry producers approach selective breeding. The findings suggest current breeding strategies may hit biological constraints earlier than anticipated.
Originaltitel: Research Note: Phenotypic trends for the multigenerational advanced intercross of the Virginia body weight lines of chickens
<p>Random samples from generation S41 of the Virginia high and low 8-week body weight lines formed the base population for producing a multigenerational reciprocal intercross population. Although genetic mapping from this intercross has been reported, lacking are phenotypic trends across multiple generations. Here, we provide phenotypic information for the parental base population, the F1 reciprocal cross, and subsequent segregating recombinant generations F<sub>2</sub> to F<sub>17</sub>. Heterosis for the selected trait in the F<sub>1</sub> was negative for both reciprocal crosses. Phenotypic correlations for the selected trait in the recombinant generations were essentially nil for both males and females as was percent sexual dimorphism and coefficients of variation.</p>