Sex-Linked Feathering Alleles (K, k+) in Chicks of Diverse Genetic Backgrounds

Effects of the sex-linked feathering alleles K and k+ on body weight, surface and cloacal temperature of chickens were examined. In chicks from a broiler parent stock, k+/w females were slightly heavier (P<.10) than K/w chicks from 21 to 31 days of age and had higher surface temperatures on Days 17, 21, and 24 of age (P<.05). The K allele was also introduced into early-feathering lines selected for high (HW) and low (LW) 8-week body weight and a line selected for high antibody response to sheep erythrocytes (HA) through the use of K/k+ sires from the broiler stock, resulting in chicks of genotypes K/k+, k+/k+, K/w, and k+/w. Surface temperatures were consistently higher (P<.05) and cloacal temperatures were similar to, or lower, in chicks from dam line HW than HA or LW. Surface temperatures were higher (P<.05) on Days 13, 16, and 20, and cloacal temperatures were lower (P<.05) on Days 13, 16, 23, and 27 in a warmer than in a cooler environment. The lack of interactions between dam line and feathering genotype indicated that rate of feathering did not act differently in these diverse genomes.