The Characterization of Lactic Acid Bacteria Strains as Components of a Biopreparation for Chickens for Slaughter

Since 2022, the European Union has banned the use of antibiotics in animal production. We conducted studies to characterize <i>Lactiplantibacillus plantarum</i> (47, AN8, and OK-B) and <i>Ligilactobacillus salivarius</i> (AN9) and evaluate their potential to create a biopreparation based on fermented whey for chickens. The following methods were used: lactic acid bacteria (LAB) culture and storage, crystal violet staining, Koch's plate method, Caco-2 cell culture, hydrophobicity test, and spectrophotometric measurements. All bacteria showed weak adhesion to polystyrene and collagen, and the <i>L. plantarum</i> species demonstrated weak adhesion to mucus. All bacteria showed strong adhesion to the intestinal epithelial cell line Caco-2. LAB showed strong autoaggregation and coaggregation with <i>E. coli</i> ATCC10536. The highest affinity for xylene was exhibited by <i>L. salivarius</i> AN9 (above 30%) while, for chloroform, the highest affinity was exhibited by <i>L. plantarum</i> OK-B (approx. 95%); the affinity for n-hexadecane for all strains was below 20%. The highest survival in the presence of bile salts (0.3%) was demonstrated by <i>L. plantarum</i> 47 (above 54%). The effect of low pH resulted in decreased viability for all strains. Significant differences were demonstrated in the concentration of lactic acid between MRS and whey medium after culturing LAB. These results will aid in qualifying these strains for further research to create a functional feed for chickens.