BACKGROUND: Gastrointestinal diseases in weaned piglets are a frequent cause of high morbidity and mortality in domestic pigs. The use of antibiotics is problematic due to increasing antibiotic resistance in bacterial populations, for which reason the use of suitable probiotics is highly recommended to maintain animal health and welfare. RESULTS: In this study, 57 strains of biologically safe lactic acid bacteria (LAB) and bifidobacteria originating from the gastrointestinal tract (GIT) of pigs were identified and characterized in terms of their probiotic properties for potential use in weaned piglets. These strains were divided into two sets based on their origin - from the GIT of wild boars (n = 41) and from the GIT of domestic pigs (n = 16). Strains obtained from wild boars exhibited greater taxonomic diversity compared to isolates from domestic pigs. While searching for coding sequences (CDS) encoding bacteriocins and bile salt hydrolases (BSH), no significant difference was detected between the two tested groups. On the other hand, CDS encoding adhesinlike factors were more frequent in the dataset isolated from wild boars than in the dataset obtained from domestic pigs. Moreover, more CDS encoding carbohydrateactive enzymes (CAZymes) were carried in the genomes of strains obtained from wild boars. Utilization of important selected carbohydrate substrates, such as starch, D-raffinose, D-mannose, Dcellobiose and gentiobiose, was confirmed by API testing. Antimicrobial activity against at least one of the five tested pathogens was found in 51% of wild boar strains but in none of the isolates from domestic pigs. CONCLUSION: This suggests that the intestinal microbiota of wild boars could serve as a promising source of probiotics for domestic pigs.

• Keywords
• Antimicrobial activity, CAZymes, Carbohydrate utilization, Domestic pigs, Probiotics, Wild boars,
• MeSH
• Bacteriocins genetics   MeSH
• Bifidobacterium * genetics   isolation & purification   MeSH
• Animals, Wild microbiology   MeSH
• Phylogeny MeSH
• Gastrointestinal Tract microbiology   MeSH
• Lactobacillales * genetics   isolation & purification   classification   MeSH
• Weaning * MeSH
• Swine MeSH
• Probiotics * MeSH
• Gastrointestinal Microbiome MeSH
• Sus scrofa microbiology   MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Amidohydrolases MeSH
• Bacteriocins MeSH
• choloylglycine hydrolase MeSH Browser

Probiotics are a potential strategy for salmonellosis control. A defined pig microbiota (DPM) mixture of nine bacterial strains previously exhibited probiotic and anti-Salmonella properties in vitro. Therefore, we evaluated its gut colonization ability and protection effect against S. typhimurium LT2-induced infection in the gnotobiotic piglet model. The DPM mixture successfully colonized the piglet gut and was stable and safe until the end of the experiment. The colon was inhabited by about 9 log CFU g-1 with a significant representation of bifidobacteria and lactobacilli compared to ileal levels around 7-8 log CFU g-1. Spore-forming clostridia and bacilli seemed to inhabit the environment only temporarily. The bacterial consortium contributed to the colonization of the gut at an entire length. The amplicon profile analysis supported the cultivation trend with a considerable representation of lactobacilli with bacilli in the ileum and bifidobacteria with clostridia in the colon. Although there was no significant Salmonella-positive elimination, it seems that the administered bacteria conferred the protection of infected piglets because of the slowed delayed infection manifestation without translocations of Salmonella cells to the blood circulation. Due to its colonization stability and potential protective anti-Salmonella traits, the DPM mixture has promising potential in pig production applications. However, advanced immunological tests are needed.

• Keywords
• Salmonella typhimurium, bacilli, bacterial consortium, bifidobacteria, clostridia, lactobacilli,
• Publication type
• Journal Article MeSH

Gnotobiotic (GN) animals with simple and defined microbiota can help to elucidate host-pathogen interferences. Hysterectomy-derived germ-free (GF) minipigs were associated at 4 and 24 h post-hysterectomy with porcine commensal mucinolytic Bifidobacterium boum RP36 (RP36) strain or non-mucinolytic strain RP37 (RP37) or at 4 h post-hysterectomy with Lactobacillus amylovorus (LA). One-week-old GN minipigs were infected with Salmonella Typhimurium LT2 strain (LT2). We monitored histological changes in the ileum, mRNA expression of Toll-like receptors (TLRs) 2, 4, and 9 and their related molecules lipopolysaccharide-binding protein (LBP), coreceptors MD-2 and CD14, adaptor proteins MyD88 and TRIF, and receptor for advanced glycation end products (RAGE) in the ileum and colon. LT2 significantly induced expression of TLR2, TLR4, MyD88, LBP, MD-2, and CD14 in the ileum and TLR4, MyD88, TRIF, LBP, and CD14 in the colon. The LT2 infection also significantly increased plasmatic levels of inflammatory markers interleukin (IL)-6 and IL-12/23p40. The previous colonization with RP37 alleviated damage of the ileum caused by the Salmonella infection, and RP37 and LA downregulated plasmatic levels of IL-6. A defined oligo-microbiota composed of bacterial species with selected properties should probably be more effective in downregulating inflammatory response than single bacteria.

• Keywords
• Bifidobacterium, Lactobacillus, Salmonella Typhimurium, Toll-like receptor, cytokines, gnotobiotic minipig, lipopolysaccharide,
• Publication type
• Journal Article MeSH