内蒙古包头地区玉米秸秆黄贮调制技术及其对育肥羊饲喂效果的研究

Yellow Silage Preparation Technology of Maize Straw and Its Feeding Effect on Fattening Sheep in Baotou Area of Inner Mongolia

旨在研究适合内蒙古包头地区玉米秸秆黄贮发酵的最佳条件,并评价玉米黄贮秸秆配方日粮对育肥羊的饲喂效果。采用三因素三水平正交试验,对黄贮发酵菌剂、发酵周期和发酵辅料等进行实验室研究,筛选最佳发酵组合;依据GB/T 20807—2006《绵羊用精饲料》标准,配制含不同比例秸秆黄贮的配方日粮,开展育肥羊饲喂试验,比较传统育肥羊饲料和玉米黄贮秸秆配方饲料对小尾寒羊的育肥效果。结果表明,3个因素对秸秆黄贮pH值影响的顺序为:发酵辅料>发酵菌剂>发酵周期,黄贮发酵条件最佳的组合为EM如金菌液秸秆发酵剂+发酵25 d+食盐。饲喂基础日粮中添加不同比例玉米秸秆黄贮的2个试验组羊只,其活体重、胴体重、单块眼肌面积显著大于饲喂传统育肥饲料的对照组羊只(P<0.05);饲喂基础日粮中黄贮添加比例为40%的试验组羊只,其饲料转化率显著高于对照组羊只(P<0.05);饲喂基础日粮中黄贮添加比例为20%的试验组羊只,其屠宰率显著高于对照组羊只(P<0.05);2个试验组羊只的日增重、大腿肌肉厚度、腰部肌肉厚度、系水力与对照组相比差异均不显著(P>0.05)。综合考虑饲喂效果以及饲喂成本因素,在基础饲料中添加40%的玉米黄贮秸秆对小尾寒羊的育肥效果最佳。

In order to study the optimum conditions for yellow silage fermentation of maize straw in Baotou region of Inner Mongolia, and to evaluate the feeding effect of the formula diet with supplementation of the prepared yellow silage on fattening sheep. Laboratory experiments on microbial fermentation agent, fermentation time duration and fermentation excipients were carried out using a three-factor and three-level orthogonal test to screen the best fermentation combination; according to GB/T 20807-2006 Concentrate for Sheep standard, the formula diet containing different proportions of yellow silage was prepared, and a feeding experiment was carried out to compare the fattening effect of traditional fattening sheep feed and formula diet supplemented with yellow silage of maize straw on Small-tailed Han sheep. The results showed that the order of the three factors influencing the pH value of yellow silage was as follows： fermentation excipient〉fermentation microbial agent〉fermentation time duration; the best combination of fermentation conditions was liquid EM fermentation microbial agent ＋fermentation 25 d＋salt; the live weight, carcass weight and single ocular muscle area of the sheep fed with different proportions of yellow slige in basal diet were significantly higher than those fed with traditional fattening diet （P〈0.05）; the feed conversion rate of sheep fed basal diet with 40% yellow silage was significantly higher than that of control group （P〈0.05）; the slaughter rate of sheep fed with 20% yellow silage in basal diet was significantly higher than that of control group （P〈0.05）; there were no significant differences in daily weight gain, thigh muscle thickness, waist muscle thickness and water holding capacity between the two experiment groups （P〉0.05）. Considering the feeding effect and the feeding cost, the best fattening effect for Small-tailed Han sheep was to add 40% into the basal diet.