Protective effects of Bacillus subtilis against Salmonella infection in the microbiome of Hy-Line Brown layers

Abstract

ObjectiveThis study investigated the effects of Bacillus subtilis CSL2 (B. subtilis CSL2) administration before Salmonella challenge on the fecal microbiota and microbial functionality of Hy-line Brown (HLB) laying hens.MethodsFecal samples were collected from control (CON), Salmonella-infected (SAL) and Salmonella-infected, probiotic-treated (PRO) groups before and after Salmonella challenge for microbiome analysis using 16S rRNA gene pyrosequencing.ResultsInfection with Salmonella led to decreased microbial diversity in hen feces; diversity was recovered with Bacillus administration. In addition, Salmonella infection triggered significant alterations in the composition of the fecal microbiota. The abundance of the phylum Firmicutes decreased while that of Proteobacteria, which includes a wide variety of pathogens, increased significantly. Bacillus administration resulted in normal levels of abundance of Firmicutes and Proteobacteria. Analysis of bacterial genera showed that Salmonella challenge decreased the population of Lactobacillus, the most abundant genus, and increased populations of Pseudomonas and Flavobacterium genera by a factor of 3 to 5. On the other hand, Bacillus administration caused the abundance of the Lactobacillus genus to recover to control levels and decreased the population of Pseudomonas significantly. Further analysis of operational taxonomic units revealed a high abundance of genes associated with two-component systems and secretion systems in the SAL group, whereas the PRO group had more genes associated with ribosomes.ConclusionThe results of this study indicate that B. subtilis CSL2 administration can modulate the microbiota in HLB laying hens, potentially acting as a probiotic to protect against Salmonella Gallinarum infection.

The effects of the supplementation of multi‐strain probiotics on intestinal microbiota, metabolites and inflammation of young SPF chickens challenged with Salmonella enterica subsp. enterica

“…Probiotic‐treated Salmonella ‐challenged chickens exhibited a reduction in Proteobacteria compared with those just Salmonella challenged. The shift in bacterial microbiota demonstrated a similar trend as that reported for S. Gallinarum in other research (Oh, Pajarillo, Chae, Kim, & Kang, ; Oh, Pajarillo, Chae, Kim, Yang, & Kang, ). In our study, we determined that the number of Lactobacillus and Oscillospira in the ProSal group was higher than in the Cont and Sal groups.…”

“…The results of apparent clustering by group suggested that chicken developed distinct microbial signatures attributable to probiotic administration and Salmonella infection. Similar results were observed in the intestinal population of poultry fed with Bacillus strains as probiotics or infected with Salmonella (Oh, Pajarillo, Chae, Kim, & Kang, ; Oh, Pajarillo, Chae, Kim, Yang, & Kang, ).…”

“…In other studies, poultry infected with strains of Salmonella exhibited a significant increase in Proteobacteria (Mon et al., ; Oh, Pajarillo, Chae, Kim, & Kang, ; Oh, Pajarillo, Chae, Kim, Yang, & Kang, ). We also demonstrated that the Sal group had significantly enriched sequences classified as Proteobacteria , whereas the Bacilli were increased in the ProSal treatment group (Figure ).…”

“…() reported that probiotics balanced intestinal mucosal inflammatory responses, leading to intestinal homeostasis. To investigate bacterial communities, the high‐throughput next‐generation sequencing method has been applied in intestinal microbiota studies of mice (Lin et al., ), broilers (Oh, Pajarillo, Chae, Kim, & Kang, ), and swine (Tanner, Chassard, Zihler Berner, & Lacroix, ). Specific‐pathogen‐free (SPF) chickens reared in an environment free from infectious organisms can be used to avoid pathogenic interference with research objectives.…”

Effects ofRhodotorula mucilaginosafermentation product on the laying performance, egg quality, jejunal mucosal morphology and intestinal microbiota of hens

“…Animals infected with strains of Salmonella exhibited a significant increase in Proteobacteria (Videnska et al ). Probiotic administration in pigs and broilers was correlated with increased abundance of Firmicutes and decreased abundance of Proteobacteria (Oh et al ; Oh et al ). Members of the Helicobacteraceae family, particularly Helicobacter , are associated with gastrointestinal diseases in many animals (Fox and Lee ; Solnick and Schauer ).…”