不同蛋白源对8～16月龄肉牛肥育效果的研究

Effect of Different Protein Sources on the Performance of Fattening Beef Cattle during 8～16 Month of Age

试验采用单因子完全随机设计 ,将 18头 8月龄西门塔儿杂种小公牛随机分为Ⅰ、Ⅱ、Ⅲ组 ,进行了 2 70d肥育试验。试验分前期 (12 0d)、中期 (90d)和后期 (6 0d) 3期。3期饲粮精粗比分别为 35∶6 5、5 5∶4 5和 6 5∶35。饲粮补充蛋白源为豆粕或玉米酒精糟。其中Ⅰ组在整个试验期全部饲喂以大豆粕为主要蛋白源的饲粮 ;Ⅱ组在前期和中期饲喂以大豆粕为主要蛋白源的饲粮 ,在后期饲喂以玉米酒精糟为主要蛋白源的饲粮 ;Ⅲ组在整个试验期全都饲喂以玉米酒精糟为主要蛋白源的饲粮。试验结果显示 :Ⅰ、Ⅱ、Ⅲ组的全期平均日增重分别为 919g、936g和 970 g。饲粮蛋白源未影响饲粮干物质、粗蛋白质、粗纤维、粗脂肪、无氮浸出物表观消化率。Ⅰ、Ⅱ、Ⅲ组牛肥育期内纯收入分别为 196 6 0元、2 6 1 78元和 5 2 2

Eighteen Simmental male cattle, 18 months of age, were randomly allocated into 3 groups and fed for 270 days in 3 stages (ie. Earlier stage (120 days), middle stage (90 days) and later stage (60 days). The ratios of concentrate to roughage in diets were 35∶65, 55∶45 and 65∶35 for groups Ⅰ, Ⅱ and Ⅲ, respectively. Soybean meal was used as protein supplement in diet throughout the experimental period for group Ⅰ and during earlier and middle stages for group Ⅱ; corn dried distillers grains (CDDG) was used as protein supplement in diets during later stage for group Ⅱ and throughout the experimental period for group Ⅲ. The results showed that the average daily weight gains throughout the experimental period were 919, 936 and 970 g for groups Ⅰ, Ⅱ and Ⅲ, respectively. The apparent digestibilities of dry matter, crude protein, coarse fiber, ether extract and nitrogen free extract in experimental diets were not affected by protein sources. The net incomes during fattening period were 196.60, 261.78 and 522.99 yuan (RMB) for groups Ⅰ, Ⅱ and Ⅲ, respectively.