Bacillus licheniformis-Fermented Products Reduce Diarrhea Incidence and Alter the Fecal Microbiota Community in Weaning Piglets

Abstract

Simple Summary: Antibiotics have been commonly used worldwide as growth promoters and for prophylactic treatment of diarrhea in weaning piglets. However, The European Union has banned the use of antibiotic growth promoters in animal production. Therefore, finding alternative solutions for preventing diarrhea in weaning piglets is urgent. Modulation of gut microbiota composition by probiotics has a beneficial effect on animal health. In this study, we assessed the effects of Bacillus licheniformis-fermented products on diarrhea incidence and the fecal microbiome composition in weaning piglets. Results showed that B. licheniformis-fermented products could improve diarrhea incidence and the fecal microbiota community in weaning piglets. These findings indicate that B. licheniformis-fermented products have the potential for development as feed additives and use as possible substitutes for antibiotics to prevent postweaning diarrhea in the pig industry.Abstract: Prophylactic use of antibiotics in-feed has been effective in decreasing the incidence of diarrhea in weaning piglets. However, the overuse of antibiotics as prophylactic or therapeutic agents in animal feed leads to the evolution of drug-resistant bacteria and antibiotic residues in pigs. This study investigated the effects of Bacillus licheniformis-fermented products on diarrhea incidence and the fecal microbial community in weaning piglets. A total of 120 crossbred piglets with an average initial body weight of 9.87 ± 1.43 kg were randomly allotted to four dietary treatments consisting of three replicate stalls with 10 piglets in each. The dietary treatments comprised a basal diet as control, control plus 1 g/kg or 4.5 g/kg of B. licheniformis-fermented products, and control plus 30 mg/kg antibiotics (bacitracin methylene disalicylate). Results showed that 4.5 g/kg of B. licheniformis-fermented product supplementation significantly reduced diarrhea incidence in weaning piglets. Principal coordinate analysis and a heatmap of species abundance indicated distinct clusters between the groups treated with antibiotics and B. licheniformis-fermented products. The bacterial richness and evenness in the feces decreased in weaning piglets fed 1 g/kg of B. licheniformis-fermented products and antibiotics. The abundance of the genera [Ruminococcus] gauvreauii group, Ruminococcaceae UCG-005, and Ruminococcaceae UCG-008 in the feces decreased in weaning piglets fed B. licheniformis-fermented products or antibiotics. The average abundance of the genus Prevotella 9 in the feces was positively correlated with the concentration Animals 2019, 9, 1145 2 of 15 of B. licheniformis-fermented products and negatively correlated with the diarrhea incidence in weaning piglets. Furthermore, the average abundance of the genus Prevotella 9 in the feces was positively correlated with the growth performance of weaning piglets. These results demonstrate that B. licheniformis-fermented products can improve diarrhea incidence and fecal microflora composition in weaning piglets.

Evaluation of Bacillus licheniformis-Fermented Feed Additive as an Antibiotic Substitute: Effect on the Growth Performance, Diarrhea Incidence, and Cecal Microbiota in Weaning Piglets

“…However, the half and total replacement of antibiotics with B. amyloliquefaciens was found to not alter the α-diversity of the microbial population in the feces of weaning piglets [19]. However, a recent study demonstrated that bacterial species richness and evenness in the feces decreased in weaning piglets fed BLF or antibiotics [11]. In the present study, we demonstrated that no difference was found in the bacterial species richness in the cecal digesta between groups.…”

“…Furthermore, the dietary supplementation of a combined mixture of B. lichenformis and Clostridium butyricum decreased the diarrhea incidence in weaning piglets [17]. Supplementing a BLF in the diet of weaning piglets alleviated the diarrhea incidence [11]. In the present study, we demonstrated that, similar to the effects of antibiotics, replacing all the bacitracin with BLF still reduced diarrhea incidence in weaning piglets.…”

“…Replacing all the bacitracin with BLF reduced the bacterial species evenness compared with the control group, while the effects were reversed in the group treated with BLF in combination with bacitracin. Mirroring the results of a previous study [11], a principal coordinate analysis with quantitative traits showed that bacterial communities were clearly distinct in the cecal digesta for groups treated with bacitracin alone, BLF alone, or both the bacitracin and the BLF. These findings demonstrated that the full of half replacement of bacitracin with BLF can have a different impact on the cecal microbiota of weaning piglets.…”

“…Antibiotics are known to reduce the incidence of post-weaning diarrhea by destroying pathogenic bacteria and changing the gut microbial composition in piglets [1]. Imbalanced fecal microbiota have been observed in response to antibiotic prophylaxis in poultry and pigs [11,32]. In addition to antibiotics, gut microbial composition and diversity can be shaped by probiotics [32].…”

“…It has been reported that in weaning piglets, probiotic supplementation in diets can have a similar effect to antibiotics [8]. The prevention of post-weaning diarrhea by the application of probiotics or probiotic-derived functional metabolites has also been investigated in weaning piglets [9][10][11]. Among the probiotic strains that have been studied, Bacillus licheniformis has been reported to have a strong ability to produce digestive enzymes and antimicrobial peptides that enhance nutrient utilization and inhibit pathogen growth [12][13][14].…”