In order to study the effects of probiotics on growth performance,digestive enzyme activity and intestinal health of broilers,300 broilers were randomly divided into 4 treatments.0%,0.1%,0.3%and 0.5%probiotic agents were added to the basal diet.The results showed that the addition of 0.1%probiotics had no significant effect on the growth performance of broilers,and the daily feed intake and daily gain of 0.3%probiotics treatment were not significantly different from those of the control group(P>0.05).Compared with the control group,the feed-to-weight ratio decreased by 8.8%,and the daily feed intake of 0.5%probiotics treatment was not significantly different from that of the control group(P>0.05),and the average daily gain was 10.4%higher than that of the control group(P<0.05).The ratio of feed to weight was 9.9%lower than that of the control group(P<0.05).0.1%probiotics had no significant effect on digestive enzyme activity in jejunum of broilers(P>0.05).Trypsin,lipase and amylase activities treated with 0.3%probiotics increased significantly by 15%,44%and 47%respectively compared with the control group(P<0.05).The activities of trypsin,lipase and amylase treated by probiotics were significantly increased by 32%,47%and 58%,respectively(P<0.05).Addition of 0.1%probiotics significantly reduced intestinal inflammation in broilers,but had no significant effect on other intestinal health indexes(P>0.05).Addition of 0.3%and 0.5%probiotics significantly increased villus height,villus-to-crypt ratio,SIgA content,intestinal barrier gene Occludin and ZO-1 expression in jejunum of broilers,but had no significant effect on crypt depth(P>0.05).The addition of 0.5%had the best effect,resulting in a 42.5%increase in SIgA content compared with the control group,an increase of 114%and a 48%increase in the expression of Occludin and ZO-1.In summary,probiotics can significantly increase the intestinal digestive enzyme activity and improve the intestinal health status of broilers,thus improving the growth performance of broilers.
probioticsbroilersgrowth performancedigestive enzymesintestinal health