Effects of Bacillus on growth, survival, immunity and digestive enzyme activities of Babylonia areolata

In order to explore whether Bacillus can replace antibiotics in the culture of Babylonia areolata, during the growth and development of B. areolata from early veliger larva to juvenile, we used Bacillus (B. coagulans, B. licheniformis) and antibiotics (sulfamethoxazole) for artificial regulation to study their effects on the growth, survival, immune and digestive enzyme activities of B. areolata. The results show that Bacillus and sulfamethoxazole promoted the growth of each trait index of B. areolata, and the difference among them was not significant (P>0.05). The survival rate of the Bacillus group was significantly higher than that of the control group and the sulfamethoxazole group in the later veliger larva stage (P<0.05). The activities of AKP, ACP, CAT, POD, GSH-Px, SOD, LPS and AMS, and MDA molality and T-AOC in Bacillus group were higher than those in the control group and the sulfamethoxazole group. The results show that appropriate use of Bacillus (B. coagulans and B. licheniformis) during the seedling breeding of B. areolata can improve the immunity and disease resistance of the body, increase the activity of digestive enzymes, promote the growth of larvae and improve the survival rate, and the effect is better than that of sulfamethoxazole.