The Effects Of Dietary Supplementation With Wheat Oligopeptides On Growth Performance,Apparent Digestibility Of Nutrients,Rumen Microflora And Intestinal Immunity In Meat Sheep

This experiment was conducted to study the effects of wheat oligopeptides on performance,apparent digestibility of nutrients,rumen microflora and intestinal immunity of meat sheep.Thirty small-tailed Han sheep rams with similar weight(35.58 ± 3.18 kg)of about 4 months old were randomly divided into two groups,with 15 sheep in each group.The control group was fed basic diet,and the experimental group was fed basic diet plus 0.3%wheat oligopeptide.The experiment was lasted 75 days,including 15 days of preliminary period and 60 days of sampling and data collecting period.During the feeding period,the leftover feed was collected and weighed daily every day to calculate the average daily feed intake.On the 1st,15 th,30th,45 th and 60 th day of the normal feeding period,the food was weighed on an empty stomach before morning feeding and recorded.The text data was used to cacluate the daily gain and feed-to-meat ratio.One week before the end of the text,sheep feces samples were collected daily to measure the apparent digestibility of nutrients.After the end of the feeding text,six sheep in each treatment group were randomly selected and slaughtered.After slaughter,rumen contents and duodenum,jejunum and ileum tissues were quickly taken to determine rumen microflora,intestinal morphology,intestinal mucosal immunoglobulin content and relative expression of s BD-1 and s BD-2 genes.The results showd that:1.Effect of wheat oligopeptide on the performance of meat sheep: the results showed that(1)Compared with the control group,the experimental group significantly increased the average daily gain of meat sheep on 30 th day(P < 0.05);(2)the average daily feed intake of the experimental group was not changed significantly compared with control group(P >0.05);(3)the feed/weight ratio of the experimental group was significantly lower than that of the control group on the 30 th day(P < 0.05).2.Effect of wheat oligopeptide on apparent digestibility of nutrients in meat sheep: the results showed that the apparent digestibility of dry matter,crude protein,neutral detergent fiber,acid detergent fiber,calcium and phosphorus were significantly increased compared with the control group(P < 0.05);Apparent digestibility of crude fat was not changed by the treatment(P > 0.05).3.Effect of wheat oligopeptide on rumen microflora of meat sheep: the results show that(1)supplementation of wheat oligopeptides had no significant effect on the diversity of rumen bacteria of meat sheep(P > 0.05);(2)at phylum level,the dominants were Bacteroidetes,Firmicutes and Spirochaetes;The relative abundance of Cyanobacteria decreased significantly(P<0.05)and that of Bacteroidetes tended to increase by the treatment(P = 0.081).(3)At the genus level,the dominants genera were Rikenellaceae RC9 gut group and Prevotella 1.4.Effect of wheat oligopeptide on intestinal immunity of meat sheep: the results showed that(1)compared with the control group,the villus height of duodenum and jejunum increased significantly by the experimental group(P < 0.05),and the recess depth of duodenum,jejunum and ileum decreased significantly(P < 0.05)by the treatment,and the value of V/C of duodenum,jejunum and ileum was increased significantly by the treatment(P < 0.05);(2)the contents of Ig A,Ig M and Ig G in duodenal mucosa of rats in the experimental group were significantly increased compared with control group(P<0.05),and the contents of Ig A and Ig M in jejunum mucosa were increased significantly by the treatment(P<0.05),meanwhile the contents of Ig A and Ig G in ileum were significantly increased by the treatment(P < 0.05);(3)the relative expression of s BD-1 gene in jejunum and ileum was significantly increased in experimental group compared with control group(P<0.05),and the relative expression of s BD-2 gene in duodenum,jejunum and ileum was significantly increased by the treatment(P<0.05).