Influence of increasing breast meat yield on muscle histology and meat quality in the chicken.

The histological characteristics, ie, myofibre types and cross-sectional areas (CSA), of pectoralis major and sartorius muscles of 20 male chickens from two lines (ten birds from each line) divergently selected for breast meat yield were compared. Moreover, some quality parameters (ie, drip loss, ultimate pH value and meat colour) of the breast muscle were recorded. The animals from both lines displayed identical pectoralis major myofibre types and CSA. A slight difference in typology, but not in myofibre CSA, was observed in the sartorius muscle: animals with the highest breast meat yield tended to have a more pronounced glycolytic character. No significant difference was observed in the quality of breast meat (pH, colour and drip loss).