A Genetic Analysis of Chick Feathering and Its Influence on Growth Rate

TWO important characteristics of meat-type chickens are feathering and growth rate. These characteristics are important because they strongly influence economic returns in the production of poultry meat. Although both feathering and growth rate are complex physiological traits there appears to be a major difference in their mode of inheritance. In the case of feather growth, single gene effects have been identified. The action of the recessive early feathering sex-linked gene k, first reported by Serebrovsky (1922) and later by Warren (1925) is now well established. In addition, a multiple allelic series of genes, the Tardy-Retarded series, has been described in White Leghorns by Jones and Hutt (1946) and in White Leghorns and Rhode Island Reds by McGibbon and Halpin (1946). In the case of growth rate no single gene effects have as yet been isolated although Maw (1935) and Kaufman (1948) found some evidence for sex-linked genes depressing body size. . . .