It was reported that, compared with the control group, different doses of lactobacilli could increase the content of IgA and IgG in the serum of mice. sows and growth performance of piglets, decreased the incidence of diarrhea in piglets, and increased the antioxidant capacity of serum in both sows and piglets. Therefore, P7, P8, and P15 might be considered as potential antibiotic alternatives for further study. Abstract Enterotoxigenic (ETEC), which expresses K88 is the principal microorganism responsible for bacterial diarrhea in pig husbandry, and the indiscriminate use of antibiotics has caused many problems; therefore, antibiotics need to be replaced in order to prevent diarrhea caused by ETEC K88. The objective of this study was to screen excellent lactic acid bacteria (LAB) strains that inhibit ETEC K88 and explore their effects as probiotic supplementation on reproduction, growth performance, diarrheal incidence, and antioxidant capacity of serum in sows and weaned piglets. Three LAB strains, P7, P8, and P15, screened from 295 LAB strains and assigned to (with high inhibitory activity against ETEC K88 were selected for a study on feeding of sows and weaned piglets. These strains were chosen for their good physiological and biochemical characteristics, excellent exopolysaccharide (EPS) production capacity, hydrophobicity, auto-aggregation ability, survival in gastrointestinal (GI) fluids, lack of hemolytic activity, and broad-spectrum activity against a wide range of microorganisms. The results indicate that LAB strains P7, P8, and P15 had significant effects on improving the reproductive performance of sows and the growth performance of weaned piglets, increasing the activity Lovastatin (Mevacor) of antioxidant enzymes and immune indexes in both. (ETEC) that express K88 fimbriae Lovastatin (Mevacor) are the principal microorganisms responsible for bacterial diarrhea in weaned piglets, which results in an economic loss of 26% [2,3]. Antibiotics are used to treat a variety of bacterial infections or suppress infections by disease-causing microorganisms, including various types of Lovastatin (Mevacor) diarrhea, but unfortunately, long-term and heavy use of antibiotics has caused many problems, such as dysbiosis of animal intestinal microbiota, drug residues, and environmental pollution . The use of antibiotics as growth promoters in diets for weaned pigs in Lovastatin (Mevacor) the European Union has been banned since 1 January 2006 (European Community Regulation 1831/2003) . With announcement No. 194 of the Ministry of Agriculture and Rural Affairs, China has totally banned the use of antibiotics in feed since 1 January 2020 because of the emergence of antimicrobial resistance in animals and humans. Some studies have shown that zinc oxide (ZnO), organic acids, feed enzymes, prebiotic oligosaccharides, and clay minerals can improve post-weaning diarrhea associated with ETEC, but the impact on the environment, risks associated with microbial resistance, and difficulty of material preparation must be considered [6,7,8]. As a consequence, antibiotic growth promoters must be replaced in order to enhance growth performance and prevent diarrhea caused by ETEC K88. Lactic acid bacteria (LAB), which are among the most common and typical probiotics, exist Lovastatin (Mevacor) widely in nature and are isolated mainly from fermented foods, soil, and animal gut and fecal matter [9,10]. Several studies have confirmed that LAB can enhance intestinal barrier function of weaned piglets. (protected the intestinal barrier function of weaned piglets against ETEC challenge ; reduced ETEC K88 in the intestines of weaned piglets , affected the abundance of pathogenic bacteria, and particularly reduced the abundance of ETEC K88 ; enhanced growth performance and decreased the incidence of diarrhea caused by ETEC K88 ; and OLL2768 was a good candidate against intestinal inflammatory damage induced by ETEC . In summary, above studies show that LAB can inhibit Rabbit polyclonal to OAT pathogenic bacteria, including intestinal imbalance caused by ETEC K88. Additionally, by immunizing gestating sows, newborn piglets receive maternal antibodies against ETEC from the colostrum, providing early and effective immune protection against diarrhea caused by ETEC infection. As the livestock industry is important worldwide, the demand for LAB in the farming industry is large, while the market for feeding LAB is still in the primary stage and the number of commercialized LAB products is relatively small at present. Therefore, this study aimed to isolate pig-derived LAB strains and screen out safe and effective LAB against ETEC K88 by comprehensively evaluating their in-vitro and in-vivo beneficial properties for both sows and piglets, and provide LAB resources for the development of complex microecological.