The intestinal microflora of piglets around weaning - with emphasis on lactobacilli.

Abstract

This study was aimed at describing the dynamics of microflora colonizing different parts of gastrointestinal tract of piglets around weaning transition with emphasis on ileal lactobacilli, as they are known for their health promoting properties. Eight piglets were slaughtered at day of weaning and four on 1 st , 2 nd , 5 th and 11 th day post weaning (pw), respectively. Digesta samples were taken from ileum (1/3 of distal small intestine), caecum and colon (40-50 cm of proximal colon) for microbial examination using selective growth media. Results revealed dramatic and time dependent changes with all observed groups and more pronounced effects in ileum than in caecum or colon. Enterobacteriaceae count was in a steady state from day of weaning until 5 th day pw whereas significantly lower counts were found on 11 th day pw. Enterococci also showed no differences during first two days but dramatically decreased levels were observed on 5 th and 11 th day pw. Yeasts counts decreased 5 days pw but recovered until 11 th day whereas number of lactobacilli decreased (p<0.01) on 1 st day and recovered within 5 days to initial level. A total amount of 72 lactobacilli colonies was picked up from counting plates, purified and identified by means of their carbohydrate fermentation ability. Results highlight L. acidophilus (44.4 %) followed by L. fermentum (35.7 %) and L. salivarius (15.3 %) being predominant species. Additionally, there was a time dependent shift with L. salivarius, L. fermentum and L. acidophilus being most abundant species before weaning whereas predominace of L. fermentum and L. salivarius on 1 st , 2 nd and 5 th day pw and L. acidophilus on 11 th day pw was observed. Our results provide a general overview of occurring changes with major groups of intestinal microbial community in weaning piglets. This could be helpful in current research for alternatives for infeed-antibiotics. As demonstrated with lactobacilli, changes may also occur within these microbial groups. Further research is needed to elucidate impact of intestinal microbial population dynamic on piglet health status during weaning transition.