QUANTITATIVE DIETARY-PROTEIN REQUIREMENTS OF CLARIAS-ISHERIENSIS (SYDENHAM 1980) (CLARIIDAE) FINGERLINGS

Six isocaloric practical diets containing graded levels of protein (25, 28, 31, 34, 37, 40%) were formulated and fed to Clarias isheriensis fingerlings (mean weight, 32.47 +/- 1.63 g) at 5% of their body weight twice daily (07.00 and 17.00 h) over 60 days in four replicated treatments using 120-litre fibreglass aquaria. Weight and protein gain were directly proportional to the protein content of the diet up to 37% incorporation. Feed - gain ratio (FGR) values improved from 25 to 34% of dietary protein treatments, beyond which there were no significant (P > 0.05) differences. Protein efficiency ratio (PER) decreased with the increasing dietary protein level, but productive protein value (PPV) and apparent protein digestibility (D(a)) were not affected (P = 0.05). These results indicate that C. isheriensis requires about 37-40% protein in a diet of mixed feeds.