Probiotics and Antimicrobial Effect of Lactiplantibacillus plantarum, Saccharomyces cerevisiae, and Bifidobacterium longum against Common Foodborne Pathogens in Poultry

The probiotic potential and antimicrobial activity of Lactiplantibacillus plantarum, Saccharomyces cerevisiae, and Bifidobacterium longum were investigated against Escherichia coli O157:H7, Salmonella typhimurium and Listeria monocytogenes. Selected strains were subjected to different acid levels (pH 2.5–6.0) and bile concentrations (1.0–3.0%). Strains were also evaluated for their antimicrobial activity by agar spot test. The potential probiotic strains tolerated pH 3.5 and above without statistically significant growth reduction. However, at pH 2.5, a significant (p \u3c 0.05) growth reduction occurred after 1 h for L. plantarum (4.32 log CFU/mL) and B. longum (5.71 log CFU/mL). S. cerevisiae maintained steady cell counts for the entire treatment period without a statistically significant (p \u3e 0.05) reduction (0.39 log CFU/mL). The results indicate at 3% bile concertation, 1.86 log CFU/mL reduction was observed for L. plantarum, while S. cerevisiae, and B. longum growth increased by 0.06 and 0.37 log CFU/mL, respectively. L. plantarum and B. longum demonstrated antimicrobial activity against E. coli O157:H7, S. typhimurium and L. monocytogenes. However, S. cerevisiae did not display any inhibition to any of the pathogens. The results indicate that L. plantarum and B. longum present probiotic potential for controlling E. coli O157:H7, S. and L. monocytogenes in poultry

Evaluating the Efficacy of Select Probiotic to Reduce the Colonization of Salmonella in Broiler Chicken

Overuse of antibiotics in agricultural has caused the spread of antibiotic resistant bacteria. Probiotics have, over the years, emerged as a viable alternative to traditional growth-promoting drugs in animal husbandry. These, among other alternatives should be aggressively evaluated under field conditions. Probiotics for chickens is an important focus in poultry industry and should be evaluated under field conditions. This study aims to assess the efficacy of selected microbes for use as probiotics in poultry production. The specific objectives include (i) to evaluate the survival of Saccharomyces cerevisiae, Lactobacillus plantarum and Bifidobacterium longum at varying pH and bile concentrations in the gastrointestinal tract (GIT) of broiler chicken, (ii) to investigate the antagonistic activity of S. cerevisiae, L. plantarum and B. longum against E.coli 0157:H7, Salmonella typhimurium and L. monocytogenes, and (iii) to evaluate the efficacy Sacchromyces Cerevisiae and Bifidobacterium longum on the growth performance and their ability to reduce the colonization of Salmonella in the cecum, liver, and spleen of broilers. Two-hundred and seventy chicks were fed with probiotic (1ppm) and challenged (oral gavage) with 10 9cfu/ml Salmonella enterica. At days 9, 14, 21 and 28 post challenge, liver, cecum and spleen were assayed for Salmonella reduction (log CFU/ml). Body weight gain was also measured. Acid tests revealed that L. plantarum grew significantly at pH 3.5 to 6 from 0 to 5 hrs. S. cerevisiae was able to survive at pH 2.5, 4.0 and 6.0 for 0 to 3hrs and at pH 3.0 from 0 to 2hrs. B. longum may have poor tolerance for strong acidic conditions showing decreased survival at pH 2.5 and 3.0 for 3 to 5 hours. S. cerevisiae did not inhibit E. coli O157:H7, Salmonella typhimurium and Listeria monocytogenes, while B. longum and L. plantarum inhibited all three pathogens. Results show that the probiotics treatments did not affect body weight gain (P\u3c0.05). The spleen and liver exhibited very little Salmonella prevalence compared to the cecum which exhibited a steady decline. This study indicates that S. cerevisae and B. longum as single or combination has the potential to reduce Salmonella in broilers and their use as probiotics should be promoted