Effects of Bacillus pumilus on growth performance, serum indexes and muscle development-related gene expression of weanling Jintang black goat

Abstract Antibiotic misuse has been a severe problem in animal husbandry. It is meaningful to replace antibiotics with Bacillus, as feed additives are indeed a research hotspot. Bacillus pumilus plays a certain role in promoting the growth performance and immunological indicators of animals. There are few reports about the function of goat-derived B. pumilus in animals until now. This study aimed to investigate the effects of B. pumilus fsznc-09 on growth performance and immune function of Jintang black goats. B. pumilus-treated group was fed with 1 ml freeze-dried agent of B. pumilus fsznc-09 at a concentration of 109 cfu/ml every 2 days. The growth performance, serum biochemical indexes, the expressions of muscle development and metabolism related genes of Jintang black goats were measured after 30 days. The results showed that the average daily gain and average daily feed intake were significantly increased, and feed conversion ratio was significantly decreased. The activities of total superoxide dismutase, alkaline phosphatase, immunoglobulin G and interferon-γ in serum of goats were significantly increased. However, the activity of malondialdehyde in serum was significantly decreased. The diameters and areas in longissimus dorsi fibre and gluteus fibre of goats were significantly decreased, while the densities in gluteus fibre of goats were significantly increased. The expressions of FAS, LPL, PPAR-γ, CAT, MYOD1, MYOG, MYF5 and MyHCI in longissimus dorsi and gluteus of goats were significantly improved. The expressions of 1, SREBP-1, MyHCIIb and MyHCIIx in longissimus dorsi and gluteus of goats were significantly increased. The expressions of FN1 in longissimus dorsi and MyHCIIa in gluteus of goats were significantly decreased. In conclusion, B. pumilus fsznc-09 can effectively improve the growth performance, immunological indicators and the expressions of muscle development and metabolism related genes of Jintang black goat.