Effects of dietary folic acid on the growth, digestive enzyme activity, immune response and antioxidant enzyme activity of blunt snout bream (Megalobrama amblycephala) fingerling

Vitamins are considered as low molecular weight organic compounds that are required in small amounts for the maintenance of metabolism, normal growth and health of fish. Folic acid is a form of water-soluble vitamin B9, which is important in amino acid and nucleotide metabolism, growth and health of most aquatic animals. Blunt snout bream is a Chinese freshwater herbivorous species that has been recognized as a main aquaculture species, with high economic value which is mostly used in the fresh water polyculture system. Because of an increase in consumer demand and the relatively low production costs of this species, its production has rapidly expanded in China with 0.7 Mt in 2012. Nowadays, several nutritional requirements have been reported about this fish including some vitamin requirements. However, no information is available regarding the folic acid requirement of blunt snout bream. Therefore, this study hypothesized that dietary folic acid may improve growth and digestion, immune and antioxidant capacities of blunt snout bream fingerlings.