添加酵母硒对乌珠穆沁羊生长性能的影响

Effect of Dietary Supplementation of Selenium-enriched Yeast on Growth Performance of Wuzhumuqin Sheep

[目的]探讨放牧条件下内蒙古锡林郭勒地区乌珠穆沁羊日粮中酵母硒的适宜添加量。[方法]将240只乌珠穆沁羊随机分为4组,其中Ⅰ组为对照组,日粮中添加无机硒(亚硒酸钠)0.3 mg/(kg·DM),Ⅱ~Ⅳ组为酵母硒添加组,日粮中分别添加0.3、0.6、0.9 mg/(kg·DM)的酵母硒。预饲期15 d,正饲期60 d。于试验第0天、第30天、第60天分别测定各组羊只的空腹体重,记录各组耗料量,计算并比较各组的平均日增重、平均日采食量及增重耗料比;同时,每组随机选取12只羊(每个重复2只)进行静脉采血,测定并比较各组的血清生长激素(GH)含量。[结果]在0~30 d和30~60 d,Ⅲ组和Ⅳ组的平均日增重显著高于Ⅰ组和Ⅱ组(P<0.05),而试验期间(0~60 d)各组平均日采食量、增重耗料比均无显著差异(P>0.05);在试验第30天和第60天,酵母硒添加组(Ⅱ~Ⅳ组)的血清GH含量均显著高于无机硒添加组(Ⅰ组)(P<0.05)。[结论]锡林郭勒地区自然放牧条件下,乌珠穆沁羊日粮中酵母硒的最适添加量为0.6 mg/(kg·DM)。

[Objective]To determine the appropriate dietary supplementation level of selenium-enriched yeast for Wuzhumuqin Sheep in Xilingol region under grazing condition. [Method]A total of 240 Wuzhumuqin Sheep were randomly assigned into one of the four groups: groupⅠserved as control group and the basil diet was supplemented with 0.3 mg/(kg·DM) of sodium selenite,groups Ⅱ to Ⅳ were experimental groups and the basil diet was supplemented with 0.3, 0.6, 0.9 mg/(kg·DM) of selenium-enriched yeast, respectively. The pre-experiment lasted for 15 days and the formal experiment lasted for 60 days. The empty body weight of the sheep were determined at the 0, 30^(th), 60^(th) day of the experiment, the feed consumption of the sheep was recorded, the average daily weight gain, average daily feed intake, and gain to feed ratio were calculated and statistically evaluated; twelve sheep were selected(two sheep for each repeat) from each group and their venous blood samples were collected to determine the serum content of growth hormone(GH). [Result]During 0-30 d and 30-60 d of the experiment, the average daily weight gain of group Ⅲ and group Ⅳ was found significantly increased compared to group Ⅰ and group Ⅱ(P <0.05), while no significant differences in average daily feed intake and gain to feed ratio between different groups were observed during the whole experimental period(0-60 d)(P>0.05); at the 30^(th) and 60^(th) day of the experiment, the serum content of GH of the seleniumenriched yeast supplementation groups(groupⅡ-Ⅳ) was significantly higher than inorganic selenium supplementation group(group Ⅰ)(P <0.05). [Conclusion]The recommended dietary supplementation of selenium-enriched yeast for Wuzhumuqin Sheep in Xilingol League under grazing condition was 0.6 mg/(kg·DM).