Abstract
This experiment was designed to collect the data on antioxidants content of guppy fed with Nannochloropsis sp. inclusion diets through partial replacement of fishmeal in feed and the effect of microalgal diet on water quality parameter of the culture system. Triplicate groups of fifteen uniform sized guppy fries were kept in each rectangular glass tank (20 L) maintaining the male and female ratio to 1:2. Different experimental diets containing Nannochloropsis sp. (0%-control; 5%-N5, 10%-N10 and 15%-N15) and commercial feed (CMF) were fed to the fishes, two times a day at 5% of their body weight for 100 consecutive days. Water quality parameters were analyzed and recorded throughout the trial period. Both physical and chemical parameters of the culture tanks were measured during the trial period. At the end of experiment, random sampling was done for growth parameter assessment and further laboratory analysis. Oxidative stress (hydrogen peroxide and lipid peroxidation) was analyzed with the carcass sample. In this study, antioxidants content of guppy showed a significant difference among the treatment. Also, improved water quality parameters were found in the treatment tanks where guppy were fed with microalgae formulated feeds. In conclusion, results from this study indicate that selected marine microalga can increase the antioxidant properties of fish that would help in production of more hardy culture species for commercial aqua farming as well as help to maintain water quality parameters of the culture system which is now become a great problem.