The isolation, identification, physiological property of pig-isolate Clostridium butyricum LY33 using lactic acid and its effects on intestinal function of weaned piglets

To research the isolation, identification, physiological property of Clostridium butyricum strain using lactic acid from pig and its effects on intestinal function of weaned piglets, the C. butyricum strain LY33 was isolated with an anaerobic culture method from the intestinal contents of healthy piglets fed with lactic acid bacteria fermented feeds. The strain LY33, which was identified as Clostridium butyricum according to morphological, physiological, biochemical and 16S rRNA sequence analyses, was found to be efficient in lactic acid utilisation and butyric acid conversion. Strain LY33 was non-toxic and resistant to heat, gastric acid and bile salts. It utilised lactic acid efficiently when cultured in LADM liquid medium (Lactic acid decomposition medium) under the initial conditions of pH 5.5 and a lactic acid concentration of 132 mmol. Strain LY33 also had inhibitory effects on Escherichia coli, Salmonella, and other pathogens. Conversely, it promoted the growth of lactic acid bacteria. Compared to the control group fed the basal diet, the indexes of intestinal function of piglets in the experimental group fed the strain LY33 preparation improved markedly, and for most of these indicators, a difference at p < .05 was achieved.Highlights In this study, one Clostridium butyricum strain LY33 was isolated from intestinal contents in healthy piglets which were fed lactic acid bacteria fermented feed, and was identified as Clostridium butyricum based on its morphological, physiological, biochemical and 16S rRNA sequence analysis. The strain LY33 had better ability of utilising lactic acid, had a certain inhibitory effect on Escherichia coli, Salmonella and other pathogens, can promote the growth of lactic acid bacteria, and the preparation of Clostridium butyricum had a good effect on improving the intestinal function of weaned piglets