Protein requirements of catfish Clarias batrachus for sustainable aquaculture

Abstract

Fingerlings of Clarias batrachus were fed on six formulated diets with different protein levels, over a period of 100 days to study their protein requirements. Growth and specific growth rate remained low when fed on low protein diets. Highest growth performance was observed in groups fed on 40.25% dietary protein irrespective of the protein source. An increase in dietary protein level (beyond 40.25%) repressed growth. The values of dissolved oxygen and excretion of ammonical nitrogen and ortho-phosphate remained low when fish were fed on 40.25% dietary protein irrespective of the protein source. But these values remained high for groups fed on Fishmeal (FM) based diets. The results clearly showed that, out of two protein sources used in these studies, soybean gives the most promising results. Therefore, the use of soybean (at 40.25% protein level) is recommended as an eco-friendly dietary protein source for Clarias batrachus