Feeding experiments were conducted twice, Experiments I and II, in order to determine an optimum dietary protein level for Tilapia nilotica by feeding them with casein diets containing corn oil as a lipid source.
Daily feed consumption was found to be affected by dietary protein or cellulose levels. With an increase in the amount of dietary protein, feed consumption decreased, thus the growth rate was better in the fish fed on the diet containing 30% protein than those fed on the 40% protein diet.
Effect of dietary cellulose levels on the feed consumption was great in the case of low protein diets. The best growth rate was obtained in the fish receiving the 30% protein diet, when its digestible energy (DE) level was sufficient for the fish. The amount of DE and nitrogen intake required for their maximum growth is estimated to be around 12-13 kcal and 160-170mg/l00g body weight/day, respectively.