PSIII-28 A Novel Direct-Fed Microbial Supports in Vitro Intestinal Integrity Upon Clostridium Perfringens Challenge

Abstract

Abstract Gastrointestinal pathogens cause productive, health, welfare, and financial losses to the beef cattle herd. Among these pathogens, Clostridium perfringens type A is of interest given its prevalence, negative effects on intestinal health, and subsequent losses caused in beef animals. Based on this rationale, we hypothesized that a novel direct-fed microbial (DFM) formulation would support the gut barrier integrity upon a challenge with C. perfringens type A. Therefore, our objective was to evaluate how a novel DFM can support the in vitro integrity of intestinal epithelial cell monolayers exposed to C. perfringens type A. Human cancer-derived epithelial intestinal Caco-2 cell monolayers were seeded in transwells for approximately 20 days. A DFM mixture containing Lactobacillus animalis, Propionibacterium freudenreichii, Bacillus licheniformis, and B. subtilis (BOVAMINE DEFEND Plus; Chr. Hansen A/S, Hørsholm, Denmark) was then administered to the apical side of the cell monolayers at 1.0 × 108 CFU/transwell. Then, C. perfringens type A (ATCC #13124) was added at 2.8 × 107 CFU/transwell. Transepithelial electrical resistance (TEER) was measured over a 16-h period, after which area under the curve (AUC) was calculated. By itself, C. perfringens type A led to a TEER decrease that reached its lowest levels at 6.5 h post-pathogen administration. Overall mean decrease in TEER was in the order of 19.3% when compared with control cells. The DFM mixture supported the integrity of the intestinal cell monolayers both with and without the C. perfringens type A challenge, improving AUC by 24.5 and 19.1%, respectively, when compared with non-challenged control cells. In comparison with the negative control cells (C. perfringens-treated), improvements on AUC ranged from 45.6 to 39.4% vs. DFM and DFM + pathogen. In conclusion, these data support our hypothesis that a DFM mixture containing L. animalis, P. freudenreichii, B. licheniformis, and B. subtilis (BOVAMINE DEFEND Plus) supports the gut barrier integrity with or without the pathogenic challenge.