Dietary Bacillus subtilis-and Clostridium butyricum-based probiotics supplement improves growth and meat quality, and alters microbiota in the excreta of broiler chickens

This study investigated the effects of the multi-probiotics consisting of Bacillus subtilis (B. subtilis) and Clostridium butyricum (C. butyricum) with varying doses (0, 0.05%, 0.1%, and 0.2%) on the growth performance, nutrient digestibility, meat quality, and cecal microbes of male broiler chickens. Seven hundred and twenty Ross 308, 1-d-old male broiler chickes were distributed into 4 dietary groups. Over 35 d of feeding, the average daily gain (ADG) was linearly elevated (P < 0.05) during d1-21 and 1 to 35 as probiotic doses increased.The average daily feed intake (ADFI) tended to be linearly (P = 0.059) increased from d 22 to 35, and was improved from d 1 to 35 (P = 0.031). Ascending doses of multi-probiotics tended to (P = 0.060) reduce Clostridium perfringens counts on d 35 and prompted (P = 0.001) the proliferation of Lactobacillus. Moreover, broilers fed a 0.1% dose of multi-probiotics had a higher pH and water-holding capacity (P < 0.05) in the breast meat. In conclusion, the 0.2% multi-probiotics could boost ADG by improving ADFI and modulating the cecal microbe. The dietary 0.1% multi-probiotics contributed to better meat quality.