Effects of dietary supplementation with Bacillus spp. and Debaryomyces spp. on broiler’s growth performance, serum characteristics, intestinal microflora and antioxidant activity

This study investigated the effect of different Bacillus spp. and Debaryomyces spp., which are screened from Melopsittacus undulates crop milk on growth performance, intestinal morphology, intestinal microflora and antioxidant abilities in broilers. By screening the Bacillus spp. and Debaryomyces spp. from parrot’s crop milk, the properties of these microbial were examined in vitro accordingly. In animal experiments, 480 1-day-old Ross 308 broilers were randomly divided into 6 treatments as control (corn-soybean meal), Bacillus velezensis with 5 × 106 cfu/kg feed (BV), Bacillus subtilis with 5 × 106 cfu/kg feed (BS), Debaryomyces hansenii with 5 × 106 cfu/kg feed (DH), B. velezensis + Saccharomyces cerevisiae with 5 × 106 cfu/kg feed (BV + SC), and B. velezensis + D. hansenii with 5 × 106 cfu/kg feed (BV + DH). The results showed that chickens in BV, BV + SC, and BV + DH groups showed significantly higher body weight and average weight gain than control group at 21 days of age. Biochemistry of triglyceride values in BV and BV + SC had significantly decreased than in control group. Intestinal lactic acid bacteria were significantly higher in BV and BS groups than in the control group in ileum. The villus height of jejunum in BV + SC and BV + DH was significantly higher than in the control group. Glutathione peroxidase activity was significantly higher in BV, BS, BV + SC groups than in the control group, but immune assays had no significant differences among the groups. Based on the results of animal growth performance, the number of lactic acids, intestinal morphology, antioxidant activity, and immune system, BV and BV + SC groups possess better feed additives for broiler chickens.HIGHLIGHTS Bacillus spp. and Debaryomyces spp. affect on growth performance, intestinal morphology, intestinal microflora and antioxidant abilities in broiler chickens. Broilers with feed additives of Bacillus velezensis, Debaryomyces hansenii, Saccharomyces cerevisiae have higher body weight and average weight gain B. velezensis and B. velezensis + Saccharomyces cerevisiae groups possess better feed additives for broiler chickens