Regression of Abdominal Fat in Broilers on Abdominal Fat in Spent Parents

A total of 261 pedigreed broilers out of 10 sires and 27 dams from a high fat line and 378 pedigreed broilers out of 11 sires and 34 dams from a low fat line were probed in the vent at 8 weeks of age as an indirect measure of abdominal fat. The broilers were weighed alive, slaughtered, and eviscerated. Abdominal fat, eviscerated carcass without giblets, and carcass shell weights were taken for each chicken. The correlations between caliper measurements and abdominal fat were below +.2. The sires and dams of the two lines were weighed alive at 14 months of age, slaughtered, eviscerated, and the same carcass measurements taken as for their broiler progeny. Sixteen of 21 sires had no measurable abdominal fat. The dams averaged 3.44% abdominal fat of live body weight compared with 1.55% for their female broiler progeny. The coefficient of variation for abdominal fat as a percentage of live weight of dams was 28%. Regressions of daughters and sons on midpoint of parents for abdominal fat as a percentage of live weight was +.305 and +.204, respectively, and were significant (P≤.05). The regression of daughters on dams and of sons on dams for abdominal fat as a percentage of live weight was +.186 and +.154, respectively, and both were significant (P≤.01).