In vivo safety evaluation of the MIYAIRI 588 strain in broilers, piglets, and turkeys

Clostridium butyricum MIYAIRI 588 (CBM 588) is a nonpathogenic, anaerobic, gram-positive bacillus characterized by the production of short-chain fatty acids, including butyrate. The safety and tolerance of CBM 588 was investigated as a feed additive for broiler chickens, weaned piglets, and turkeys. CBM 588 administered to broilers at doses up to 5 × 10 7 CFU/g feed for 42 days produced no detrimental effects on zootechnical performance, natural mortality, hematology, or biochemical parameters. Piglets receiving CBM 588 at doses up to 5 × 10 7 CFU/g feed for 42 days showed no significant differences from controls in zootechnical performance, mortality, or morbidity. Finally, CBM 588 administered to turkeys at doses up to 2.5 × 10 7 CFU/g feed for 84 days produced no detrimental effects on zootechnical performance, hematology, or biochemical parameters. Some improvements in zootechnical performance were seen with CBM 588, including improved average daily gain (ADG) and feed conversion for broilers from days 1 to 21 as well as final body weight and overall ADG for turkeys. Overall, CBM 588 administered in feed at dose up to 5 × 10 7 CFU/g (broilers and piglets) or 2.5 × 10 7 CFU/g (turkeys) was shown to be safe and well-tolerated in all tested animals and may provide some nutritional benefit when added to standard commercial feed.