复合营养素对扎布耶盐山羊育肥效果和肉品质的影响

研究复合营养素对育肥扎布耶盐山羊的产肉性能和肉品质的影响。选取60只体重相近的2岁龄扎布耶盐山羊羯羊,随机分为空白对照组、试验Ⅰ组、试验Ⅱ组和试验Ⅲ组。在试验期间,每组每日均按照农牧民放牧习惯自由放牧,晚上补饲精料颗粒料,添加量为280 g/d,燕麦青干草为自由采食;试验Ⅰ组、试验Ⅱ组和试验Ⅲ组分别添加复合营养素Ⅰ、复合营养素Ⅱ和复合营养素Ⅲ各20 g/只;分别在试验第56天的早晨测定所有实验羊活重,计算其在育肥期间的增重率;从各试验组和对照组中分别随机选取10只羊进行屠宰,测定其产肉性能指标以及背最长肌肉品质指标。结果显示,育肥扎布耶盐山羊的补饲日粮中添加复合营养素可使其生长速度加快,3个复合营养素添加组的活体增重和增重率极显著高于对照组（P〈0.01）,屠宰率显著或极显著高于对照组（P〈0.05或P〈0.01）。3个复合营养素添加组的背最长肌水分含量降低（P〉0.05）,但脂肪含量增加（P〈0.01）,剪切力下降（P〉0.05）,表明肌肉的口感明显提升;多不饱和脂肪酸、必需氨基酸、VA、VB_1、VB_（12）含量显著或极显著增加（P〈0.05或P〈0.01）,胆固醇含量降低（P〉0.05）,表明其营养价值明显提高。研究结果为今后在饲草料相对缺乏的藏北牧区开展扎布耶盐山羊的短期育肥提供了技术支撑。

Effects of Dietary Supplementation with Compound Nutrients on Fattening Performance and Meat Quality of Zabuye Goats

The objective of this study was to evaluate the effects of dietary supplementation with compound nutrients on meat productivity and quality of Zabuye goats. A total of 60 2-year-old Zabuye wether goats with similar body weight were randomly assigned into control group, experimental Ⅰ group, experimental Ⅱ group and experimental Ⅲ group. During the experimental period, the goats were freely grazed daily according to the herdsmen′ grazing habit; supplementary feeding was made with 280 g of pelleted concentrate for each goat per day at night; fresh grass and hay of oat were fed to appetite; the diet of experimental Ⅰ,Ⅱand Ⅲ groups was supplemented with 20 g of compound nutrients Ⅰ, Ⅱ and Ⅲ per goat, respectively; on the morning of the 56 th day of the experiment, the live weight of the goats was determined and their weight gain rate during the fattening period was calculated; 10 goats were randomly selected from the control group and each experimental group, respective, they were subsequently slaughtered and the indicators associated with meat productivity and longissimus dorsi meat quality were calculated and statistically analyzed. The results showed that the dietary supplementation with compound nutrients promoted the growth of fattening Zabuye goats; the 3 compound nutrients supplementation groups had extremely significantly higher live weight gain and weight gain rate compared to the control group（P〈0.01）, and had significantly or extremely significantly higher dressing percentage to the control group（P〈0.05 or P〈0.01）. Reduced moisture content（P〈0.05）, increased fat content（P〈0.01） and decreased shear stress（P〈0.05） of the longissimus dorsi were observed in the 3 compound nutrients supplementation groups,indicating that the taste of the meat was obviously improved. Furthermore, the contents of polyunsaturated fatty acids, essential amino acids, VA, VB_1 and VB_（12） of the longissimus dorsi in the 3 compound nutrients supplementation groups were found significantly or extremely significantly elevated（P〈0.05 or P〈0.01）, while the content of cholesterol were found reduced（P〈0.05）, indicating that the nutritive value of the meat was also obviously improved. Our results provide technical support for the short term fattening of Zabuye goats in the northern Tibetan pastoral areas where forage is relatively deficient.