湘西黄牛杂交组合育肥及肉质性能研究

选取18月龄湘西黄牛、西本（西门塔尔牛×湘西黄牛）、利本（利木赞牛×湘西黄牛）、西西本（西门塔尔牛×西本）、利西本（利木赞牛×西本）共24头,于舍饲条件下补饲精料,进行70d的育肥试验。结果表明：利西本三元杂交牛的增重水平和育肥效益明显优于其他组合和湘西黄牛,利西本三元杂交牛的日增重1.21 kg;屠宰率58.44%,净肉率47.68%;胴体质量与产量等级评定表明：利西本三元杂交牛牛肉指标达到了特级标准;产量达到了国内优质高档牛肉的重量标准。肉质特性测定表明：利本杂交牛肉品大理石纹较为丰富,利西本杂交牛肉品较细嫩、柔软;各组合间氨基酸含量差异不显著（P〉0.05）,而利西本和湘西黄牛臀肌总氨基酸含量、必需氨基酸含量显著高于背肌（P〈0.05）,其他组合间差异不显著（P〉0.05）。

Fattening Performance and Meat Quality of Hybridized Combinations of Xiangxi Cattle

A total of 24 Xiangxi yellow cattle and its different hybridized combinations at the age of 18-month-old were selected and divided into five groups（Xiangxi cattle,Simmental × Xiangxi cattle,Limousin × Xiangxi cattle,Simmental × Simmental × Xiangxi cattle,Limousin × Simmental × Xiangxi cattle）,fattened forcefully under barn feeding condition for 70 ds,for studying their fattening performance,carcass characteristic and meat quality.The results showed that the body weight gain（BWG） level and fatten benefit of three-way cross of Limousin × Simmental × Xiangxi cattle were obviously superior to the other groups,with the average daily gain（ADG）1.21 kg,dressing percentage 58.44 %,pure meat percentage 47.68 %.The grade estimation of carcass quality and output indicated that,the index of Limousin × Simmental × Xiangxi cattle reached the special grade,and the beef yield reached the weight standard for domestic top-grade beef.The measurement of meat performance suggested that the marbling of Limousin × Xiangxi cattle were rich,and the meat of Limousin × Simmental × Xiangxi cattle tasted more tender and soft.The determination of amino acids showed that there was no significant difference among the groups（P 0.05）,while the total amino acids and essential amino acids in gluteus of Limousin × Simmental × Xiangxi cattle and Xiangxi cattle were significantly higher than those in back muscle（P0.05）,no significant difference among other combinations.