A Comparative Study On Meat Performance,Meat Quality Of Beef Cattle Of Different Breeds Under The Same Feeding Conditions

The purpose of the article was to investigate the differences of meat production,meat quality and the mechanism of different breeds under the same feeding conditions.The experiments contained two parts:(1)The comparison of meat production,meat quality of three different breeds.(2)The mechanism of differences of meat quality of different breeds.Experiment 1:Six healthy beef cattle of each different breeds with similar age(six months)and body condition were chosen,including Simmental crossbred cattle(Simmental×Xuanhan yellow cattle),Cattle-yaks(Jersey×Yak)and Xuanhan yellow cattle to compare the meat performance,meat nutritional quality of different breeds.(1)The dry performance and carcass index such as liveweight,carcass weight of Simmental crossbred cattle was higher than those of Cattle-yaks and Xuanhan yellow cattle significantly(P<0.05).The fat depth of Simmental crossbred cattle and Cattle-yaks were higher than that of Xuanhan yellow cattle(P<0.05).(2)The carcass characteristics of Simmental crossbred cattle,such as carcass length or others,were higher than those of Cattle-yaks and Xuanhan yellow cattle significantly(P<0.05).(3)The primal cut of Simmental crossbred cattle,except longissimus dorsi,were higher than those of Cattle-yaks and Xuanhan yellow cattle(P<0.05).(4)The intramuscular fat of Xuanhan yellow cattle was higher than that of Cattle-yaks,the Cattle-yaks was higher than Simmental crossbred cattle(P<0.05).The protein of longissimus dorsi of Cattle-yaks was higher than that of Simmental crossbred cattle and Xuanhan yellow cattle(P<0.05).The ash of longissimus dorsi of Simmental crossbred cattle was higher than that of Cattle-yaks and Xuanhan yellow cattle(P<0.05).(5)The water holding capacity of Xuanhan yellow cattle was higher than that of Simmental crossbred cattle and Cattle-yaks(P<0.05).The L~*、a~*and b~*of longissimus dorsi of Cattle-yaks was higher than that of Simmental crossbred and Xuanhan yellow cattle(P<0.05).(6)The flavor contents of longissimus dorsi of Cattle-yaks was higher than that of Simmental crossbred and Xuanhan yellow cattle(P<0.05).The mineral contents of longissimus dorsi of Simmental crossbred cattle was higher than that of Cattle-yaks and Xuanhan yellow cattle(P<0.05).The amino acids contents and composition of Cattle-yaks were greater than those of Simmental crossbred and Xuanhan yellow cattle(P<0.05).The fatty acid composition of Simmental crossbred cattle was greater than those of Xuanhan yellow cattle and Cattle-yaks(P<0.05).Experimental 2:The mechanism of differences of meat quality of different breeds.(1)The diameter of muscle fiber of Xuanhan yellow cattle was smaller than that of Simmental crossbred cattle and Cattle-yaks(P<0.05).(2)The My HCⅠgenes expression of Simmental crossbred and Xuanhan yellow cattle were higher than that of Cattle-yaks(P<0.05).The My HCⅡa andⅡx genes expression of Cattle-yaks were higher than those of Simmental crossbred and Xuanhan yellow cattle(P<0.05).(3)The genes related to intramuscular fat synthesis of Xuanhan yellow cattle,such as FAS and GPAT1,were higher than those of Cattle-yaks and Simmental crossbred cattle(P<0.05).The genes related to intramuscular fat transport of Xuanhan yellow cattle and Cattle-yaks,such as CD36 and LPL were higher than those of Simmental crossbred cattle(P<0.05).The genes related to intramuscular fat resolve of Simmental crossbred cattle,such as HSL and MGL,were higher than those of Cattle-yaks and Xuanhan yellow cattle(P<0.05).In conclusion,the dry performance and meat performance of Simmental crossbred cattle were higher than those of Cattle-yaks and Xuanhan yellow cattle significantly.The intramuscular fat and tenderness of Xuanhan yellow cattle were higher than those of Simmental crossbred cattle and Cattle-yaks.The flavor contents and protein levels of Cattle-yaks were higher than those of Simmental crossbred cattle and Xuanhan yellow cattle.The My HC I genes and genes related to intramuscular fat synthesis such as FAS and GPAT1 of Xuanhan yellow cattle were the highest,and that might be the reason of higher tenderness of meat of Xuanhan yellow cattle.