Genetic Correlations Between Six- and Seven-Week-Old Broilers

The genetic relationship between carcass traits in broiler chickens at 6 and 7 weeks of age was determined. Two-hundred and sixteen male broilers from 42 sires and 108 dams with 2 full sibs/dam were slaughtered at 41 and 48 days of age. One offspring per dam was slaughtered at each age. Means of 41-day-old birds are presented first and 48-day-old birds second: live weights 1435, 1872 g; carcass weights 877, 1200 g; abdominal fat weights 23.4, 41.7 g; percent abdominal fat/live weight 2.04, 2.22; percent abdominal fat/carcass weight 3.30, 3.47. Genetic correlations between weeks were: .58 (live weight), .66 (carcass weight), .48 (abdominal fat), .45 (% abdominal fat/live weight), and .42 (% abdominal fat/carcass weight). Records obtained on 6-week-old full sibs might be useful in a selection program to improve traits in 7-week-old birds.