尿素对羊瘤胃饲料降解率影响的研究

为了探索尿素对饲料利用率的影响,以瘤胃瘘管羊为实验动物,采用尼龙袋法,研究了尿素浓度梯度对饲料在羊瘤胃内降解率和主要养分含量变化的影响。选择3只瘤胃瘘管羊为实验动物,实验设对照组和试验组,对照组未添加尿素,试验组尿素浓度分别设为1%、2%、3%、4%和5%,测定饲料在瘤胃内6、12和24h时的粗脂肪、粗纤维、灰分、粗蛋白、钙含量和总降解率。结果表明,尿素添加水平在2%和3%时,饲料的消化率显著高于对照组和5%尿素组,饲料蛋白质、纤维素和脂肪含量显著低于对照组和5%尿素组,说明适量添加尿素可促进饲料营养物质利用率;添加2%和3%尿素可促进饲料钙的前期利用率,添加3%和4%尿素可促进饲料灰分的前期利用率。

Study on the Effects of Urea on the Degradability of Feed in Rumen of Sheep

In order to explore the effects of urea on the feed efficiency, rumen fistula sheep was used as test animal to study the effects of urea concentration gradients on the degradability of feed in the sheep rumen and the content changes of main nutrients by using nylon-bag method. Three rumen fistula sheep were selected as test animals. Control group (no urea) and test groups(adding 1%, 2%, 3%, 4% and 5% urea) were set. The content of crude fat,crude fiber,ash,crude protein,calcium and total degradation rate in the 6th , 12th , 24th hour in rumen were measured. The results showed that the feed degradability at the addition level of 2% and 3% was significantly higher than that of control group and 5% urea group, which indicated that suitable amount of urea could promote the utilization rate of feed nutrients. Adding 2% and 3% urea could promote the early-period utilization rate of calcium in feed and adding 3% and 4% urea could promote the early-period utilization rate of ash in the feed.