Effect Of Lactobacillus Complex On The Intestinal Structure And The Performance Of Broiler

Bacterial resistance and veterinary drugs residues causes many potential harm indirectly to food security, ecological environment, human and animal health. More and more studies focus on probiotics and oligosaccharides which are antibiotic alternatives. In the present study, the lactobacilli bacteria were isolated from Taihang chicken cecum. We observed the agglutination characteristics of the lactobacilli bacteria and studied the inhibition of probiotic compound to the E. coli O78 in vitro combination. Meanwhile, its effect on broiler intestinal microflora and morphology, serum biochemical parameters and performance were investigated. The main results were as follows:1. According to the results of microscopic examination, three lactobacilli bacteria strains(Lactobacillus brevis, Enterococcus faecalis, Enterococcus cecum) were isolated from health Taihang chicken cecum.2. The results of the agglutination test showed that the auto-aggregative rate of Lactobacillus brevis was higher than others, while the cecum enterococci was the lowest at 14 h. The results of the cross agglutination with Escherichia coli were that Lactobacillus brevis was the strongest and Enterococcus cecum was the weakest.3. When the E. coli O78 were culture in the medium containing inulin and lactobacilli bacteria, its growth and reproduction were inhibited. However, there was no different when the concentration was increased.4. Ross 308 broiler chicken at 240 day-old were randomly divided into four groups. Group I was treated as the control. Group II was supplied commodity probiotic to drinking water according to the instructions of the manufacturer. Group III was treated 3‰ probiotics to the drinking water. Group IV was as 3‰ probiotic compound group. All of the animals in this study were treated to the normal management and immunization. The test period was 28-days. The index of serum biochemistry, the quantity of cecum flora and the structure of duodenum and jejunum were detected at 7th days, 14 th days and 28 days respectively. The results were as follows:(1) Compared to the control group, there was no differences between the number of Lactobacillus and E.coli in other groups at 7th days(P>0.05). The number of lactobacillus was increased in group III at 14 th days(P <0.05), meanwhile group II and IV were increased significantly(P<0.01). The number of E.coli was no difference among group II, III and IV(P > 0.05). The number of lactic acid bacteria in group II, group III and group IV increased at 28 th days(P <0.05). The number of E. coli in group II and group IV was decreased(P <0.05), but there has no difference in group III(P> 0.05).(2) Compared to the control group, duodenal villus height, the proportion of villus height and recessus were decreased in group IV at 7th days(P <0.05). Group II and group III were no difference(P> 0.05). The villus height, the villus height and recessus proportion of duodenum and jejunum in group II III, IV were increased at 14 th days and 28 th days(P <0.05).(3) The alkaline phosphatase and superoxide dismutase in group II and IV were changed compared to control group at 7th days(P <0.05). Group II, group Ⅲ and group IV were changed at 14 th days(P<0.05). Blood glucose in group IV decreased 5.74%(P <0.05), but in group II and group III it was increased significantly. The alkaline phosphatase and superoxide dismutase in group II and IV increased significantly at 28 th days(P <0.05).(4) There was no significant difference on the ponderal and feed-weight ratio in each group compared to the control group at 7th days(P> 0.05). The ponderal of group IV growed faster at 14 th days(P <0.05). At 28 th days, the feed-weight ratio decreased obviously in group II, group III and group IV(P<0.05).Overall, the auto-coagulate rate of lactobacillus brevis was the highest, and the cross-coagulation of lactobacillus brevis was the strongest. When the E. coli O78 were culture in the medium containing inulin and lactobacilli bacteria, its growth and reproduction were inhibited. The property of the production of chicken, the microbial flora and blood biochemical index in cecum were improved. The structure of duodenum and jejunum was optimized.