Carcass traits, abdominal fat deposition and chemical composition of commercial meat type chicken during a twenty week growing period

Arbor Acres Regular broilers were reared on litter floor till 20 weeks of age. At 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18 and 20 weeks of age 10 birds per sex were slaughtered. Carcass weight, weight of the thigh and drumsticks with bone and skin, weight of the breast (P. major, P. minor) with bone and skin, breast fillet and abdominal fat were measured. For total body chemical composition analysis 5 birds per sex were used from all age groups as stated above. Dry matter, crude protein, crude fat and crude ash was determined for the whole body. The yield of the thighs and drumsticks rose in a linear manner in both sexes till 9 weeks of age. In male broilers the percentage proportion of the thighs and drumsticks related to liveweight peaked at 26% at 20 weeks of age, in females at 22%. Abdominal fat deposition till 5 weeks of age was low in both sexes. After 5 weeks of age female broilers deposited abdominal fat at a faster rate as males. Till 20 weeks of age the females deposited 5.9% (264 g) abdominal fat, males only 2.4% (130 g). Crude fat content in the dry matter of the whole body at 5, 12 and 20 weeks in males and females respectively were 12.0% and 11.6%, 14.7% and 11.4%, 18.7% and 30.6%. Crude protein and crude ash content of the whole body showed significantly less age and sex effects as crude fat. The differences between sexes in dry matter content and its changes with age were influenced for the most by crude fat content of the body.