Evaluation of Potential Probiotic Properties of Lactobacillus and Bacillus Strains Derived from Various Sources for Their Potential Use in Swine Feeding.

Beneficial effects of probiotics are relevant to the various potential properties of individual strains, and they may also relate to the original sources of the probiotic strains. This study aimed to characterize the potential probiotic properties of the strains originating from various sources for probiotics use in swine feeding. A total of 9 potential probiotic strains, seven lactobacilli and 2 bacilli, were examined for antimicrobial production against swine pathogens, adhesion and anti-adhesion of potential probiotic strains to IPEC-J2 cells, aggregation ability, host defense peptide expression, and hemolytic assay. The results highlight that all strains derived from different sources could exhibit probiotic properties, although different abilities were observed. L. rhamnosus SD11 exhibited the highest inhibitory effect against all pathogens compared to other strains. Bacillus licheniformis KMP-9, B. subtilis KMP-N004, and L. fermentum SD7 gave the highest internalization and that related to high abilities of exclusion, competition, and displacement inhibition to pathogens. Such strains also gave a higher co-aggregation to all pathogens compared to other potential probiotic strains. L. rhamnosus GG, L. fermentum SD7, L. rhamnosus SD4, and B. subtilis KMP-N004 had significantly higher pBD-2 mRNA expression than other strains. None of potential probiotic strains showed hemolytic activity. In conclusion, the strains derived from either humans or animals possessed desirable probiotic properties including inhibition against porcine pathogens, adhesion capacity to porcine enterocytes, anti-adhesion pathogens to porcine enterocytes, and modulated innate immunity. Results indicate that these probiotic strains may be good candidates for use in swine feeding to reduce the risk of infection.