Isolation and identification of probiotic lactobacilli from ruminant animals

Abstract

Background Lactobacillus strains are a group of bacteria that provide health benefits to their hosts when consumed in proper amounts. They are which exhibit an important for intestinal microflora that constitutes a beneficial mechanism responsible for antimicrobial activity. Ruminant animals such as cattle, buffalo, goat, and sheep have formed a symbiotic relationship with ruminal microorganisms that synthesize fiber digesting enzymes. The microbial flora obtained from ruminal ingesta is an output of the composition, nature, and quality of the animals’ feed. It is found that the dominating flora are usually starch and complex polysaccharide degrading microbiota. Objective The aim of the present study was to isolate and identify probiotic lactobacilli present in some ruminant animals to investigate interspecies differences in probiotic Lactobacillus contents. Materials and methods Sixty samples were collected in triple manner under aseptic conditions from buffalo, cattle, sheep and goats including rectal, buccal, and nasal swabs. Following DNA extraction from the isolated bacteria, 16S rRNA multiplex polymerase chain reaction analysis was performed to recognize the obtained isolates. Results and conclusion A total of 38 isolates were identified as lactobacillus species including 7, 14, 8, and 9 isolates from buffalo, cattle, sheep, and goat, respectively. The buffalo samples displayed the lowest variability in lactobacilli with the identification of Lactobacillus delbrueckii only. Cattle, goat, and sheep samples showed the presence of Lactobacillus casei, Lactobacillus acidophillus, L. delbrueckii, Lactobacillus gasseri, and Lactobacillus rhamnosus. It is found that L. gasseri was the most frequently isolated species in cattle followed by L. rhamnosus, while L. delbrueckii was the most frequently isolated species in goat followed by L. casei. L. gasseri was the most frequently isolated strain in sheep followed by L. acidophillus and L. rhamnosus. These strains should be investigated in more detail, individually or in combination, for their potential health benefits. Understanding how these species interact with other microbiota community members in each host as well as how they interact with host cells, particularly immune cells, can provide valuable insight into their function both in health and disease.