Studies on the protein requirement of postlarvae Of the penaeid prawn Penaeus indicus H. Milne Edwards Using purified diets

Abstract

Six purified diets were formulated and prepared using casein, starch, flshand- groundnut oil mixture ( 1 : 1 ratio), vitamins, minerals and other additives, with the protein content varying from 20 to 70%, to study the protein requirement of the postlarvae fPL 1 to PL 42) of the prawn Penaeus indicus. The results of the feeding experiments conducted separately on group I (PLl to PLIO), group II (PLll to PL25) and group III (PL27 to PL42) for a duration of 10, 15 and 15 days, respectively, showed that the growth of group I postlarvae increased with the increasing protein content of the diet up to 40% and declined thereafter. The growth obtained by the diet with 40% protein was highly significant (P <C 0.01). In group II postlarvae, the protein requirement was between 30 and 50%. In group HI postlarvae, maximum growth was obtained with the diet with 30% protein and it was significantly different (P <C 0.05) from the performances of the other diets. It is concluded that the dietary protein requirement of postlarvae decreases from 40%in the initial stages to 30% as they grow to advanced stages. Similarly, the rate of growth was found to be relatively faster in the young postlarvae.