[Feeding Lactobacillus plantarum and Lactobacillus casei increased microbial diversity and short chain fatty acids production in the gut-intestinal tract of weaning piglets].

The objective of the study was to study the effects of Lactobacillus plantarum and Lactobacillus casei on the changes in composition and quantity of microbial populations and the concentrations of short chain fatty acids in the gut digesta of piglets before and after weaning, to explore the mechanisms of the tested two strains to relieve weaning stress.Fifteen litters of piglets (Duroc×Yorkshire×Landrace) at the age of 7 days were randomly allocated to 3 groups (5 each), including the control group with an oral administration of saline, LP group with L. plantarum and and LC group, with L. casei. On day 21, 24 and 35, the piglets were slaughtered, and the ileum and colon digesta were analyzed for microbial populations and short chain fatty acids.In the ileum and colon, the test strains significantly increased the microbial diversity (P<0.05), promoted the growth of Lactobacilli spp. and Bifidobacteria spp. after 2 weeks of post-weaning. The two test strains increased the concentration of acetate, propionate, butyrate and total short chain fatty acids both in ileum and colon before weaning, and the concentration of acetate, total short chain fatty acids after weaning. Correlation analysis showed that the decreased diarrhea rate before weaning in the LP and LC groups was significant associated with the increased short chain fatty acids concentration and total bacteria of ileum and colon, the increased height of the ileum villi. The improved average daily gain presented a correlation with the increased concentration of acetate and total short chain fatty acids of colon.The findings imply that the tested strains are contribute to increase the microbial diversity, the quantities of beneficial bacteria and the production of short chain fatty acids in the gut intestinal tract of weaning piglets.