小麦饲料中添加木聚糖酶对高原型藏羊胃肠道发育的影响

旨在分析小麦粉中添加木聚糖酶(xylanase, Xyl)对藏羊羔羊胃肠道发育的影响。选择同质性良好的2～3月龄高原型藏羊公羔60只，随机分为两组，每组30只，各组内设置5个重复。对照组(Control group)饲喂不含木聚糖酶的日粮，试验组(Test group)饲喂含0.2%木聚糖酶的日粮，试验分为预饲期10 d和正试期90 d。饲养试验结束时，两组各随机选取5只羔羊进行屠宰，采集消化道组织置于多聚甲醛固定，并收集血液、瘤胃和空肠内容物。结果显示：1)与对照组相比，试验组瘤胃的角质层厚度、颗粒层厚度，瓣胃的乳头长度、乳头宽度、角质层厚度、颗粒层厚度，皱胃的黏膜厚度以及十二指肠的肌层厚度，空肠的绒毛高度、黏膜厚度，回肠的肌层厚度显著提高(P<0.05);2)对照组瘤胃和血清的LPS含量显著高于试验组(P<0.05);3)相较于对照组，试验组瘤胃的糜蛋白酶、胰蛋白酶、脂肪酶活性以及空肠的糜蛋白酶、α-淀粉酶活性显著提高(P<0.05);4)试验组瘤胃的总抗氧化能力水平、谷胱甘肽过氧化物酶及过氧化氢酶活性以及空肠的总抗氧化能力水平、谷胱甘肽过氧化物酶、超氧化物歧化酶...

Effects of Xylanase Supplementation in Wheat Diet on Gastrointestinal Development of Plateau Tibetan Sheep

The purpose of this experiment was to investigate the effect of xylanase (Xyl) added to wheat flour on the development of gastrointestinal tract of Tibetan lamb. Sixty plateau Tibetan lambs aged 2-3 months with good homogeneity were randomly divided into two groups with 30 lambs in each group and 5 replicates each. The control group was fed without xylanase, and the test group was fed the diet supplemented with 0.2% xylanase. The experimental period was divided into 10 days of pre-feeding period and 90 days of positive trial period. At the end of the feeding experiment, six lambs in each group were randomly selected for slaughter, the digestive tract tissues were collected and fixed in paraformaldehyde. And blood, the contents of rumen and jejunum were collected at the same time. The results showed that: 1) Compared with the control group, the thickness of rumen cuticle and granular layer, the length and width of omasum nipple, the thickness of omasum cuticle and granular layer, the thickness of abomasal mucosa, and duodenal muscle layer, the height of jejunal villi and the thickness of jejunum mucosa, the thickness of ileal muscle layer in the experimental group were significantly increased (P<0.05); 2) The contents of rumen and serum LPS in the control group were significantly higher than those in the experimental group (P<0.05); 3) Compared with the control group, the activities of rumen chymotrypsin, trypsin and lipase, the activities of jejunal chymotrypsin and α-Amylase increased significantly (P<0.05); 4) The total antioxidant capacity and the activities of glutathione peroxidase and catalase in rumen, the total antioxidant capacity of jejunum, the activities of glutathione peroxidase, superoxide dismutase and catalase of jejunum in the experimental group were significantly higher than those in the control group (P<0.05); 5) There was no significant difference in rumen and jejunum pH between the two groups (P>0.05). In conclusion, the addition of 0.2% xylanase to wheat feed can effectively reduce the concentration of LPS in rumen and serum of plateau Tibetan sheep, promote the morphological development of gastrointestinal tract, enhance digestive enzyme activity, and improve antioxidant capacity.