Development of breast muscle and meat quality in Arbor Acres broilers, Jingxing 100 crossbred chickens and Beijing fatty chickens.

The objective of this experiment was to examine development of breast muscle and myofiber of M. pectoralis superficialis in three chicken breeds. Commercial broiler chickens (Arbor Acres broilers, AA), crossbred chickens (Jingxing 100 crossbred chickens, JXC) and Chinese native chickens (Beijing fatty chickens, BJF) were grown up to 98d to estimate myofiber density, and size (area, and diameter of myofibers) in P. superficialis. At 42, 56, 70, 84, and 98d of age, Pectoralis muscle was used to evaluate breast muscle weight, breast yield, and tenderness (shear force value). Results indicate that commercial broilers have higher breast weight, and higher shear force value than crossbred chickens and Chinese native chickens, that may be due to an increased myofiber diameter and area in Pectoralis muscle. It is suggested that histological properties of myofibers play an important role in increasing the shear force value of meat.