Screening of cattle gut associated Bacillus strains for their potential use as animal probiotic

Abstract

Use of antibiotic in animal feed pose a significant risk to human health. Over the last decade uses of probiotics increasingly viewed as an alternative to antibiotic. Bacillus are currently being used as feed supplements in animal diet, due to their enhanced tolerance rate and survivability under harsh gut environment. Animal gut is a rich source for Bacillus species isolation. There is still a scarcity of information on the Bacillus species of livestock species. The present study was carried out to identify Bacillus species from animal gut to evaluate their probiotic potential. Three (NCCP-2004a, NCCP-2029 and NCCP-2029) strains were selected as putative probiotics strains based on their super acid and bile survival rates. These isolates were identified as Bacillus subtilis subsp. inaquosorum (NCCP-2029, NCCP-2025). Bacillus tequilensis (NCCP-2004a) by 16S rRNA gene sequencing. NCCP-2004a elicited best results regarding antimicrobial potential and its ability to survive on acid and bile conditions. The results of present study demonstrated that the B. tequilensis showed a promising alternative probiotic candidate to the use of antibiotics in the dairy feeding system.