The Relationship Between Embryonic and Postnatal Growth in Japanese Quail

Abstract

For many years, geneticists and physiologists have been interested in possible genetic and/or phenotypic correlations between day-old chick or embryo parameters and subsequent growth. Attempts have been made to correlate the small variations in individual egg weight/chick weight ratios with body weight ages after hatching (Godfrey and Jaap, 1952) but the slight correlations noted were without any significance. Other efforts, such as those of McNally and Byerly (1936), Byerly et al. (1938), Coleman et al. (1964) have been directed towards a study of the line or breed differences in the number of somites during early stages of incubation. Significant differences have been noted, but no correlations with postnatal growth have been observed. Since most of these studies involved non-pedigreed individuals, and since Zervas and Collins (1965) reported some significant sire and line differences in weight of chicken embryos at 14 days of incubation, a study was initiated in an effort…