Effects of Yeast Culture on Growth Performance,Intestinal Mucosal Structure and Intestinal Microflora of Broilers

This experiment was conducted to evaluate the effects of yeast culture on growth performance,intestinal mucosal structure and intestinal microflora of broilers.Two hundred and forty one-day-old Arbor Acre broilers were randomly divided into 6 groups with 4 replicates per group and 10 chicks per replicate.The chicks in control group(group Ⅰ) were fed with a basal diet,and those in experimental groups(groups Ⅱ,Ⅲ,Ⅳ,Ⅴ and Ⅵ) were fed the basal diet supplemented with 0.05%,0.10%,0.15%,0.20% and 0.25% yeast culture,respectively.The experiment lasted for 21 days.The results showed as follows: 1) the average daily gain and average feed intake in groups Ⅴ and Ⅵ were significantly higher than those in control group(P0.05),and there was no significant difference in feed/gain among all groups(P0.05).2) Compared with the control group,the villus height and villus height to crypt depth ratio(V/C) in duodenum,jejunum and ileum in group Ⅴ were significantly increased(P0.05),while the crypt depth was significantly decreased(P0.05).3) The number of Escherichia coli in jejunum,ileum and cecum in group Ⅴ was significantly lower than that in control group(P0.05),while the number of Lactobacillus was significantly higher than that in control group(P0.05),and there was no significant difference in the number of Bifidobacterium among all groups(P0.05).The results indicate that yeast culture has the functions of regulating intestinal microflora and intestinal mucosal structure,and improving the growth performance.The appropriate supplemental level of yeast culture of broilers aged 1 to 21 days is 0.20% under the condition of this experiment.