Study On Changes Of Structural Characteristics Of Muscle Fiber During Development Of Wuzhumuqin Sheep

Muscle fibers were the basic composition of skeletal muscle. The histology characteristics of muscle fibers directly influenced the muscle quality. The natural grazing Wuzhumuqin sheeps, from1to18mo. of age, were employed in the study. And used the histochemical methods, HE and EVG, to analysis the changes of intramuscular connective tissue during the growth of Wuzhumuqin sheep. The changes of the muscle fiber types were determined by method of ATPase. The method of SDS-PAGE was employed to separated myosin heavy chain isoforms (MyCH). There are main conclusions as follow:The diameter of skeletal muscle fibers were increasing during the growth of Wuzhumuqin sheep. The diameter of LD was increased slowly. In general, the diameter of skeletal muscle fibers achieved a best stage in9month-age.The thickness of endomysium was increasing during the growth of Wuzhumuqin sheep. The thickness of perimysium in DAO and LD were increasing with growth of Wuzhumuqin sheep. But The thickness of perimysium of TB、ST and BF were decreasing during9momth-age to12momth-age,and then increasing.On the whole, the content of type I and type II a (red muscle) in skeletal muscle was relatively abundant. Particularly, in LD, the vast majority of muscle was red. the content of type II a in ST was up to64.13%. So this stage is the best time to promote muscle growth.This study explains the features of connective tissue and muscle fibers in skeletal muscle of Wuzhumuqin sheeps during growth of sheep. Based on our study, we can provide a reliable reference data to guide livestock production and meat processing.