Screening of probiotic candidates in a simulated piglet small intestine in vitro model

The CoMiniGut in vitro model mimicking the small intestine of piglets was used to evaluate mode of action of four probiotic strains to assess their potential as a preventive measure against development of post-weaning diarrhea in pigs. The in vitro model was challenged with pathogenic enterotoxigenic Escherichia coli F4, and the short-chain fatty acid profile and the microbial composition were assessed. Four probiotic strains were evaluated in the in vitro model: Lactobacillus rhamnosus, Enterococcus faecium, Bifidobacterium breve and Faecalibacterium prausnitzii. Significant differences observed in short chain fatty acid profile and enumeration of Enterobacteriaceae, coliforms and lactic acid bacteria were accounted to variation between inoculating material or pathogen challenge rather than probiotic treatment. Probiotic administration influenced microbial composition to smaller extend. In vitro models mimicking the small intestine of piglets do seem to be a relevant tool for investigating mode of action of probiotics, however, learnings from this study are that the experimental setup has to be chosen with care. Considering that the setup in this study could have been improved, it is difficult to recognize the specific mode of action of the tested probiotics and to evaluate their potential as preventive measure against PWD in pigs.