Functional evaluation of Bacillus licheniformis PF9 for its potential in controlling enterotoxigenic Escherichia coli in weaned piglets

Lacticaseibacillus paracasei subsp. paracasei Q- 1 Exhibits Good Safety and Effectively Prevents Escherichia coli K99-Induced Diarrhea in Mice

Escherichia is a common pathogen causing diarrhea in livestock and poultry, posing a serious threat to intestinal health and leading to significant economic losses in the animal husbandry industry. While antibiotics have been used to treat Escherichia coli diarrhea, their numerous drawbacks have led to increasing attention on probiotic interventions. In this study, Lacticaseibacillus paracasei subsp. paracasei Q-1 (L. paracasei subsp. paracasei Q-1) was isolated from fresh cow dung, and its in vitro and in vivo safety and probiotic properties were evaluated. In vitro experiments demonstrated that L. paracasei subsp. paracasei Q-1 exhibited good antimicrobial activity against Escherichia coli K99, along with key probiotic characteristics such as acid production, acid and bile salt tolerance, high-temperature resistance, hydrophobicity, and cell adhesion. Furthermore, it showed no hemolytic activity, gelatinase activity, or mucin-degrading activity, and it only exhibited decarboxylase activity for histamine. While resistant to certain antibiotics, no significant resistance genes were detected, indicating favorable probiotic and safety profiles. In vivo, acute toxicity tests in mice revealed no signs of acute poisoning after 14 days of high-dose oral administration. A 28-day oral toxicity test showed that different doses did not affect organ indices, cause bacterial translocation, alter blood biochemical parameters, or damage the ileum. In the infection protection experiment, oral administration of L. paracasei subsp. paracasei Q-1 significantly increased the survival rate of Escherichia coli K99-infected mice from 50 to 80%. In conclusion, L. paracasei subsp. paracasei Q-1 demonstrated excellent safety and probiotic properties both in vitro and in vivo and showed promising potential in preventing Escherichia coli K99 infections, with possible applications in animal health management.

Antibiotics and Opportunities of Their Alternatives in Pig Production: Mechanisms Through Modulating Intestinal Microbiota on Intestinal Health and Growth

Antibiotics at subtherapeutic levels have been used in pig diets as antimicrobial growth promoters. However, concerns about antibiotic resistance have increased the demand for alternatives to these antimicrobial growth promoters. This review paper explores the mechanisms through which antimicrobial growth promoters and their alternatives exert their antimicrobial effects. Additionally, this systemic review also covers how modulation of intestinal microbiota by antimicrobial growth promoters or their alternatives affects intestinal health and, subsequently, growth of pigs. The mechanisms and effects of antimicrobial growth promoters and their alternatives on intestinal microbiota, intestinal health, and growth are diverse and inconsistent. Therefore, pig producers should carefully assess which alternative is the most effective for optimizing both profitability and the health status of pigs in their production system.

Berberine alleviates enterotoxigenic Escherichia coli-induced intestinal mucosal barrier function damage in a piglet model by modulation of the intestinal microbiome

Introduction

Enterotoxic Escherichia coli (ETEC) is the main pathogen that causes diarrhea, especially in young children. This disease can lead to substantial morbidity and mortality and is a major global health concern. Managing ETEC infections is challenging owing to the increasing prevalence of antibiotic resistance. Berberine, categorized as a substance with similarities in "medicine and food," has been used in China for hundreds of years to treat gastrointestinal disorders and bacteria-induced diarrhea. This study investigated the preventive effect of dietary berberine on the intestinal mucosal barrier induced by ETEC and the microbial community within the intestines of weaned piglets.

Methods

Twenty-four piglets were randomly divided into four groups. Piglets were administered either a standard diet or a standard diet supplemented with berberine at concentrations of 0.05 and 0.1%. and orally administered ETEC or saline.

Results

Dietary supplementation with berberine reduced diamine oxidase, d-lactate, and endotoxin levels in piglets infected with ETEC (P < 0.05). Berberine increased jejunal villus height, villus/crypt ratio, mucosal thickness (P < 0.05), and goblet cell numbers in the villi and crypts (P < 0.05). Furthermore, berberine increased the optical density of mucin 2 and the mucin 2, P-glycoprotein, and CYP3A4 mRNA expression levels (P < 0.05). Berberine increased the expressions of zonula occludins-1 (ZO-1), zonula occludins-2 (ZO-2), Claudin-1, Occludin, and E-cadherin in the ileum (P < 0.05). Moreover, berberine increased the expression of BCL2, reduced intestinal epithelial cell apoptosis (P < 0.05) and decreased the expression of BAX and BAK in the duodenum and jejunum, as well as that of CASP3 and CASP9 in the duodenum and ileum (P < 0.05). Berberine decreased the expression of IL-1β, IL-6, IL-8, TNF-α, and IFN-γ (P < 0.05) and elevated total volatile fatty acids, acetic acid, propionic acid, valeric acid, and isovaleric acid concentrations (P < 0.05). Notably, berberine enhanced the abundance of beneficial bacteria including Enterococcus, Holdemanella, Weissella, Pediococcus, Muribaculum, Colidextribacter, Agathobacter, Roseburia, Clostridium, Fusicatenibacter, and Bifidobacterium. Simultaneously, the relative abundance of harmful and pathogenic bacteria, such as Prevotella, Paraprevotella, Corynebacterium, Catenisphaera, Streptococcus, Enterobacter, and Collinsella, decreased (P < 0.05).

Discussion

Berberine alleviated ETEC-induced intestinal mucosal barrier damage in weaned piglets models. This is associated with enhancement of the physical, chemical, and immune barrier functions of piglets by enhancing intestinal microbiota homeostasis.

Probiotic Bacillus licheniformis DSMZ 28710 improves sow milk microbiota and enhances piglet health outcomes

Maintaining a diverse and balanced sow milk microbiome is essential to piglet development. Thus, this study aimed to examine the effects of probiotic Bacillus licheniformis supplementation on the microbiome composition of sow colostrum and milk, and to review associated health findings in piglets. B. licheniformis DSMZ 28710 was supplemented at 10 g/day as feed additive before predicted farrowing until weaning by top dressing. Colostrum and milk samples were collected for metagenomic DNA extraction, 16s rRNA sequencing, and bioinformatics analyses for bacterial microbiota diversity. Results indicated that the supplementation increased the abundances of beneficial bacteria, such as Lactobacillus, Pediococcus, Bacteroides, and Bifidobacterium, while decreasing the abundances of pathogenic bacteria, such as Staphylococcus aureus, Enterobacteriaceae, and Campylobacter in the colostrum. The supplementation increased diversity while maintaining richness and evenness. Moreover, the rise in predicted microbial community metabolic function in membrane transport pathways provides crucial evidence showing that the supplementation is potentially beneficial to piglets, as these pathways are important for providing nutrients and immunity to offspring. This research highlights the importance of microbiome composition in sow milk and the potential of B. licheniformis supplementation as a means to improve piglet health and development.

Bacillus spp. as potential probiotics: promoting piglet growth by improving intestinal health

The application of Bacillus spp. as probiotics in the swine industry, particularly for piglet production, has garnered significant attention in recent years. This review aimed to summarized the role and mechanisms of Bacillus spp. in promoting growth and maintaining gut health in piglets. Bacillus spp. can enhance intestinal barrier function by promoting the proliferation and repair of intestinal epithelial cells and increasing mucosal barrier integrity, thereby reducing the risk of pathogenic microbial invasion. Additionally, Bacillus spp. can activate the intestinal immune system of piglets, thereby enhancing the body's resistance to diseases. Moreover, Bacillus spp. can optimize the gut microbial community structure, enhance the activity of beneficial bacteria such as Lactobacillus, and inhibit the growth of harmful bacteria such as Escherichia coli, ultimately promoting piglet growth performance and improving feed efficiency. Bacillus spp. has advantages as well as challenges as an animal probiotic, and safety evaluation should be conducted when using the newly isolated Bacillus spp. This review provides a scientific basis for the application of Bacillus spp. in modern piglet production, highlighting their potential in improving the efficiency of livestock production and animal welfare.