Ex-situ Evaluation of Chironomid Larvae as a Potential Supplementary Food in Aquaculture

Due to the steady growth of the human population, the demand for fish as dietary protein increases globally. Though sea fishes are the main source of fish protein, freshwater fishes also occupy a significant part of the global market. There is a need to improve the nutritional value of freshwater edible fishes along with their production. The present study investigates the role of chironomid larvae as an alternate fish feed and their influence on the nutritional value of fish. Experiments were conducted with banded gourami ( Trichogaster fasciata ) fed on larvae of the aquatic insect Chironomus striatipennis (F1 diet), dry commercially available Tubifex (F2 diet), and commercially available dry granular fish food (F3 diet). The results show that total protein content is higher and cholesterol level is lower in fish fed on the F1 diet in comparison to fish fed on other diets. Moreover, the fish fed on the F1 diet contains a lower amount of free fatty acids and adequate amounts of saturated and unsaturated fatty acids. Comparing the ω6:ω3 and ω3:ω6 ratios it appears that the fish fed on the F1 diet is a better source of nutrition than fish fed on F2 and F3 diets, respectively. The high amount of palmitoleic acid, DHA and EPA in fish fed on the F1 diet, established C. striatipennis larvae as a suitable food source for T. fasciata culturing, as well as ascertaining this fish species to be a nutritious food source for humans.