Protein Requirement Of Ompok Bimaculatus (Bloch, 1794) Larvae

A 22 d experiment was carried out to study the protein requirement of Ompok bimaculatus larvae (weight 0.11 +/- 0.01 g; length 20.49 +/- 0.70 mm). Three different formulated feeds were prepared with graded levels of crude protein i.e., with low (35% CP; LP), medium (40% CP; MP) and high (45% CP; HP) crude protein levels. The water quality parameters were optimum during the whole experimental duration. The survival rate was more than 70%. The fish grew to 0.34 +/- 0.06, 0.91 +/- 0.15 and 0.36 +/- 0.07 g, respectively in LP, MP and HP groups. The final weight was significantly (P<0.01) higher in MP having 40% CP in the diet. Both the net weight gain and specific growth rate were significantly (P<0.05) higher in MP having 40% CP in the diet as compared to LP and HP. The FCR was also significantly (P<0.05) lower in MP having 40% protein in the diet when compared with LP and HP. However, the protein efficiency ratio was similar (P>0.05) among the three treatment groups. Further, it was also revealed that the activities of enzymes in the digestive tract namely, a-amylase, lipase and pepsin were significantly (P<0.05) higher in MP diet having 40% crude protein. The present experiment, thus. revealed that 40% CP was sufficient for the optimum growth and survival of O. bimaculatus larvae.