低蛋白日粮中添加复合中草药制剂对肉鸡器官指数、肠道消化酶活力、盲肠挥发性脂肪酸及盲肠微生物菌群的影响OA

This study aimed to investigate the effects of supplementing a compound Chinese herbal preparation in low-protein diets on the organ indices,intestinal digestive enzyme activities,cecal volatile fatty acids,and cecal microbial flora of broilers.A total of 600 healthy 1-day-old Tianlu black chickens(half male and half female)with similar body weight were randomly divided into 5 groups,with 6 replicates per group and 20 birds per replicate.The CON group(control group)was fed a basal diet;LP Ⅰ group was fed a low-protein diet with crude protein(CP)content 1.5％lower than that of the CON group;LP Ⅱ group was fed a low-protein diet with CP content 3％lower than that of the CON group;LP Ⅰ+HE group was fed the low-protein diet(1.5％lower CP than the CON group)supplemented with 0.32％compound Chinese herbal preparation;LP Ⅱ+HE group was fed the low-protein diet(3％lower CP than the CON)supplemented with 0.32％compound Chinese herbal preparation.The results showed that:(1)The spleen index in the LP Ⅰ+HE group increased significantly by 100％,116.67％,100％,and 100％compared with the CON group,LP Ⅰ group,LP Ⅱ group,and LP Ⅱ+HE group,respectively(P＜0.05).The thymus index in the LP Ⅰ+HE group increased significantly by 100％compared with the CON group and LP Ⅰ group,respectively(P＜0.05).(2)The duodenal trypsin activity in the LP Ⅰ+HE group increased significantly by 40.20％and 31.78％compared with the LP Ⅰ group and LP Ⅱ group,respectively(P＜0.05).The duodenal lipase activity in the LP Ⅰ+HE group increased significantly by 31.88％compared with the LP Ⅰ group(P＜0.05).The jejunal lipase activity in the LP Ⅰ+HE group increased significantly by 175.71％,145.41％,and 162.86％compared with the CON group,LP Ⅰ group,and LP Ⅱ group,respectively(P＜0.05).Meanwhile,the jejunal lipase activity in the LP Ⅱ+HE group increased significantly by 123.07％,98.59％,and 112.45％compared with the CON group,LP Ⅰ group,and LP Ⅱ group,respectively(P＜0.05).(3)The acetic acid content in the cecal digesta of the LP Ⅰ+HE group increased significantly by 36.87％and 60.16％compared with the LP Ⅱ+HE group and LP Ⅱ group,respectively(P＜0.05).The propionic acid content in the LP Ⅰ+HE group increased significantly by 84.62％and 101.75％compared with the LP Ⅱ group and LP Ⅱ+HE group,respectively(P＜0.05).The butyric acid content in the LP Ⅰ+HE group increased significantly by 160.95％,302.99％,and 214.71％compared with the CON group,LP Ⅰ group,and LP Ⅱ group,respectively(P＜0.05).The butyric acid content in the LP Ⅱ+HE group increased significantly by 221.86％,396.67％,288.57％,and 23.46％compared with the CON group,LP Ⅰ group,LP Ⅱ group,and LP Ⅰ+HE group,respectively(P＜0.05).The isovaleric acid content in the LP Ⅱ+HE group increased significantly by 93.58％,90.89％,458.52％,and 80.99％compared with the CON group,LP Ⅰ group,LP Ⅱ group,and LP Ⅰ+HE group,respectively(P＜0.05).The LP Ⅰ+HE group showed significant increases in the Feature index by 42.02％,54.50％,39.14％,and 58.19％;the ACE index by 41.90％,54.46％,39.01％,and 58.00％;and the Chao1 index by 41.78％,54.56％,38.87％,and 57.78％compared with the CON group,LP Ⅰ group,LP Ⅱ group,and LP Ⅱ+HE group,respectively(P＜0.05).The PD_whole_tree index in the LP Ⅰ+HE group increased significantly by 18.18％and 13.64％compared with the LP Ⅰ group and LPⅡ+HE group,respectively(P＜0.05).The abundance of Bacteroides in the LP Ⅰ+HE group increased significantly by 57.43％,48.27％,and 59.39％compared with the CON group,LP Ⅰ group,and LP Ⅱ group,respectively.The abundance of Oscillospira in the LP Ⅱ+HE group increased significantly by 138.10％,80.72％,100.00％,and 77.87％compared with the CON group,LP Ⅰ group,LP Ⅱ group,and LP Ⅰ+HE group,respectively.Under the conditions of this experiment,supplementing 0.32％compound Chinese herbal preparation in a low-protein diet(with CP level 1.5％lower than the basal diet)could significantly increase the organ indices,intestinal digestive enzyme activities,and cecal volatile fatty acid content of broilers,and improve the composition and structure of the cecal microbial flora.