A factorial floor pen trail was conducted to study the effects of formulating isonitrogenous and isoenergetic diets varying in fish meal levels (0 and 50 g/kg) with or without the ionophoric anti-coccidial agent narasin (0 and 60 mg/kg of diet) on performance of broiler chicks. Chick body weight, daily gain, feed intake and feed conversion ratio were determined during experimental period. The results indicated that body weight at 20 d, daily gain from 0-20 d , feed intake from 11-20 d and 0-20 d were all significantly increased with 50 g/kg fish meal inclusion in the diets. Narasin, on the other hand, had no such effect and did not result in any interaction with fish meal level on chick performance. These data demonstrated that the beneficial effects of fish meal on broiler performances are mediated mainly via improvement of feed consumption. These results also indicated that under coccidial and necrotic enteritis free environment, narasin growth promoter effect was insignificant (P>0.05).
