Nutritional evaluation of fermented Jatropha protein concentrate in Labeo rohita fingerlings

Jatroha protein concentrate (JPC) was prepared by iso‐electric precipitation method. A 45‐day feeding trial was conducted for the nutritional evaluation of JPC and fermented Jatropha protein concentrate (FJPC) in Labeo rohita fingerlings. Seven iso‐nitrogenous (340 g kg^?1 CP) and iso‐energetic (17 MJ kg^?1) diets such as C (soy protein concentrate⁾, T₁ (50 g kg^?1 JPC), T₂ (100 g kg^?1 JPC), T₃ (200 g kg^?1 JPC), T₄ (50 g kg^?1 FJPC), T₅ (100 g kg^?1 FJPC) and T₆ (200 g kg^?1 FJPC) were fed to respective groups. The weight gain % and protein effciency ratio showed a decreasing trend with higher inclusion of JPC whereas these parameters increased gradually on higher inclusion of FJPC. FCR showed the reverse trend. The protease, GOTand GPT activities of FJPC fed groups were significantly higher than their non‐fermented counterparts whereas a reverse trend was observed for LDH and MDH enzyme activities in muscle and liver. The survival rate was 100% in all the treatment groups except for T₂ and T₃. Phorbol esters (PEs) in FJPC was non‐detectable. Results suggested that solid state fermentation with Aspergillus niger is an effective method for removal of PEs and FJPC is a promising protein source in aquafeed.