Study on the histological features and growth characteristics of muscle of Longdong beef cattle during fattening

In order to make clear of the histological features and changes of muscle of Longdong beef cattle,psoas major,longissimus dorsi and biceps femoris of cow carcass were taken from three different body weights(300～400kg,400～500kg and 500～600kg).The experiment was studied by paraffin embedding and H E staining,the result was observed and analyzed under the microscope.The results indicated that the muscle fiber diameter of psoas major,longissimus dorsi and biceps femoris were(29.04±6.99) μm,(43.60±12.61)μm and(45.95±13.63)μm.The muscle fiber density of Psoas major,Longissimus dorsi and Biceps femoris were(441.07±38.30)n/mm2,(238.1±19.80)n/mm2 and(191.88±49.89) n/mm2.The results showed that,as body weight increased,muscle fiber diameter and connective tissue increased,but muscle fiber density had no significant differences(P0.05).Among psoas major,longissimus dorsi and biceps femoris,the muscle fiber diameter of psoas major was the smallest and the muscle density was the largest.The connective tissue of longissimus dorsi and biceps femoris were much richer than that of psoas major.