GROWTH, FEED UTILIZATION AND BODY COMPOSITION OF MAGUR Clarias batrachus FED DIETS CONTAINING DIFFERENT PLANT PROTEINS: PARTIAL OR TOTAL SUBSTITUTION OF FISH MEAL

In the present work, the effect of the dietary incorporation of vitamin C on growth performance and intestinal histology were tested in monosex Nile tilapia (Oreochromis niloticus). Total 180 number of O. niloticus fingerlings were randomly divided into four groups each in triplicates. The control group T1 was fed on a basal diet, while the T2, T3 and T4 were fed on basal diets, supplemented with vitamin C at the doses of 100, 200 and 300 mg kg⁻¹ respectively. After 90 days of feeding trial, growth parameters were analysed and the intestinal tissues were collected for histological observation.

The results suggested that the T4 group showed the significantly (p<0.05) higher weight gain and elevated average growth rate as compared to the other groups. Average food intake showed no significant (p>0.05) difference between the control and treatment groups. Abnormalities including severe necrosis in the intestinal villi, intact mucosa with moderate mucinous degeneration, Swelling of goblet cells, reduced villi height, increase in the number of goblet cells, less crypt depth, increase in the number of infiltrated leucocytes and vacuolation were observed in the intestinal histology of control fishes. All the treatment groups successfully surpassed the control group in terms of the normal cellular structure, heights of intestinal villi, the number of goblet cells and infiltrated leucocytes. Hence, vitamin C could be used as a feed additive in order to enhance the growth and improve the structure of the intestinal mucosal epithelium in monosex Nile tilapia.