Abstract

In the present study, the effect of four dietary treatments with different inclusion levels of biofloc meal, that is M_BFM0%, M_BFM5%, M_BFM10% and M_BFM20%, on the Litopenaeus vannamei growth performance, water quality, immune response, and antioxidant status were evaluated. Biofloc meal was prepared using molasses as a carbon source. Growth performances, immunological parameters were investigated in addition to pathological examination of shrimp and culture water using microbiological and molecular methods. The results showed that higher inclusion levels of biofloc meal in the diets, i.e., M_BFM10% and M_BFM20%, resulted in higher growth rate, final body weight, and lower feed conversion ratio (p<0.05). The biofloc meal enhanced phagocytic, lysozyme activities and antioxidative capacity in the L. vannamei provided with diet containing high inclusion levels of biofloc meal (M_BFM20%) (p<0.05). 16S rRNA and random amplified polymorphic DNA (RAPD) were applied to track the changes in microbial evolution in the culture system. The results of 16S rRNA and RAPD confirmed that the diets of the different culture system have effect on the evolution of the microbial communities in the culture system. In conclusion, higher inclusion levels of biofloc meal in the shrimp diet helps to improve growth performance, water quality and health of L. vannamei. The higher inclusion level of M_BFM20% is recommended.

Keywords

biofloc meal, alternatives, fish meal, fish oil, vibrio, nutritional value, microbial communities, polymorphic DNA, aquatic animal diseases