Carcase characteristics, meat quality, nutrient composition, serum biochemistry and oxidant/antioxidant status in white striping-affected broiler chickens fed diets based on maize-soybean meal.

1. Effects of the incidence of white striping (WS) in relation to carcase weights and yields, breast meat quality and composition, serum biochemistry and oxidant/antioxidant status of breast meat in broiler chickens were investigated.2. The study consisted of 180, one-d-old male broiler chickens fed maize-soybean meal-based starter, grower, finisher and withdrawal diets identical to commercial chicken diets. On d 49, all the birds were slaughtered and breast fillets were visually scored for the incidence of WS. Breast meat and blood samples were collected and categorised based on the presence or absence of WS.3. The study revealed greater slaughter weight, carcase and breast fillet weights and yields, lower pHu and higher cooking loss of breast meat with WS lesions (P < 0.05). WS-affected breast fillets had greater fat and lower crude protein contents in comparison with normal meat (P < 0.001). Serum creatine kinase levels were greater in broilers with WS (P = 0.011), whereas oxidant/antioxidant status of breast meat remained unaffected.4. Taken together, the presence of WS on breast muscle altered the quality and nutrient composition of breast fillets and serum creatine kinase levels in broiler chickens fed diets based on maize-soybean meal. Nevertheless, WS was more common in heavier broilers having higher breast weight and yield.

True metabolisable energy values of some feedingstuffs.

1. The apparent metabolisable energy (AME) and the true metabolisable energy (TME) contents of some feedingstuffs were determined with cockerels. The test materials consisted of feed-grade lentil, lentil bran and wild vetch seed. 2. The average values of nitrogen lost, endogenous energy losses (EEL) and endogenous energy losses corrected to zero-nitrogen balance (EELN) were found to be 1.18 g, 62.13 kJ and 21.51 kJ/bird/48h, respectively, from adult cockerels given an energy supply as 50 g glucose during starvation. 3. The nitrogen-corrected apparent metabolisable energy (AME(N)) values for feed-grade lentil, lentil bran and wild vetch seed, respectively, were 6.84, 3.05 and 14.31 kJ/g dry matter. The nitrogen-corrected true metabolisable energy (TMEN) values for the respective feedingstuffs were 7.44, 3.65 and 14.90 kJ/g dry matter.