饲粮添加乳酸片球菌和低聚木糖对肉兔生产性能和肠道发育的影响OA

This study investigated the effects of dietary supplementation with Lactococcus lactis and xylo-oligosaccharides(XOS)and their combination on growth performance and intestinal development of meat rabbits.A total of 600 New Zealand rabbits weaned at 28 days of age,with similar body weights and good health were randomly divided into 5 groups with 12 replicates per group and 10 rabbits per replicate.The control group were fed the basal diet,antibiotic group were fed the basal diet supplemented with 100 mg/kg enramycin(8％)+1200 mg/kg chlortetracycline(15％),Lactobacillus lactis group were fed the basal diet+100 mg/kg Lactobacillus lactis,XOS group were fed the basal diet+100 mg/kg XOS,and combination group were fed the basal diet+100 mg/kg Lactococcus lactis+100 mg/kg XOS.The pre-trial period lasted for 7 days and the experimental period lasted for 42 days.The results showed that the combination group had significantly higher average daily gain(ADG)and lower feed conversion ratio(FCR)than the control group and the XOS group(P＜0.05),ADG improved by 6.7％,4.4％,and FCR decreased by 6.4％,4.4％,respectively,though these metrics were not significantly different from the antibiotic group(P＞0.05).The combination group had significantly lower diarrhea rate and mortality than the control group and the XOS group(P＜0.05),with reductions of 48.1％,40.9％and 57.9％,52.9％,respectively,but was not significantly different from the antibiotic group(P＞0.05).The combination group of had significantly higher eviscerated weight,dressed weight,eviscerated rate,and dressed rate than the control group and the XOS group(P＜0.05),with increases of 7.9％,5.4％;6.3％,5.1％;3.3％,2.2％;1.6％,2.0％,respectively,but was not significantly different from the antibiotic group(P＞0.05).Intestinal morphological analysis revealed that the combination group had significantly higher villus height(VH)and VH/crypt depth(CD)ratio in the duodenum and ileum compared with the control and XOS groups(P＜0.05),with improvements of 7.6％,4.3％and 11.6％,4.3％for VH,and 18.3％,10.9％and 26.5％,15.4％for VH/CD ratio,respectively.CD in the combination group was significantly lower than in the control and XOS groups(P＜0.05),with reductions of 9.0％,5.9％and 11.5％,7.3％in the duodenum and ileum,respectively,though CD was not significantly different from the antibiotic group(P＞0.05).In conclusion,the combination group of Lactococcus lactis+XOS promoted intestinal mucosal development,reduced diarrhea incidence and mortality,and thereby enhanced growth performance and carcass traits in meat rabbits.