Dietary protein requirement of bighead catfish (Clarias macrocephalus Gunther, 1864) fingerling

Abstract

The study was conducted in order to find the protein requirement of bighead catfish (Clarias macrocephalus) fingerling. The initial weight of fish was 6.29 g/ind and raised them in 8 weeks. The experiment was set up with six dietary treatments including six protein levels such as 25%, 30%, 35%, 40%, 45% and 50% with an isoenergy of approximately 4.5 Kcal/g and an isolipidic diets of 8%. Results show that the protein level effected on the survival rate. The 25% protein diet had the lowest survival rate of 67.78% while those in the remaining treatments varied from 91.1% to 100%. The specific growth rates (SGR) of fish were maximal at 3.26% per day in the 45% protein diet and minimal at 1.92% per day in the 25% protein diet. The protein efficiency ratios (PER) decreased as the protein levels in diets increased. The protein content affected significantly by the dietary protein levels. Using the Broken-line method and based on the SGR, the dietary protein requirement for bighead catfish was 46.1%.