The Influence of Age on Expression of Genes Controlling Rate of Chick Feathering

THE differences wich exist in rate of feathering of various breeds have become a major problem in the production of high quality broilers. The discrimination of the market against “bare backs” has influenced poultry breeders to endeavor to develop strains of heavy breeds that are well feathered at the broiler age. Observation of the growing chick has shown two major genetic types of feathering, namely, early and late. Serebrovsky (1922) reported evidence that a sex-linked gene affects the rate of feathering. Warren (1925) confirmed the findings of Serebrovsky. The dominant gene is late feathering which is typical of most heavy breeds, and its recessive allelomorph, early feathering, is found in the Mediterranean breeds. The gene controls the rate of feathering from hatching throughout the growing period. Warren (1933) described another type, retarded feathering, which behaves as a simple autosomal recessive factor. Its influence is to modify the number of secondaries . . .