EFFECTS OF DIETARY VITAMIN-A, VITAMIN-E, AND VITAMIN-C ON THE OVARIANDEVELOPMENT OF PENAEUS-JAPONICUS

A feeding experiment was conducted to evaluate the effect of non-suppl ementation of individual vitamins A, E, and C on the ovarian developme nt of P. japonicus (mean weight=20.21+/-0.87 g). Vitamin A palmitate, DL-alpha-tocopherol, and L-ascorbyl-2-phosphate magnesium (APM) were u sed as the vitamin A, E, and C sources, respectively. A control diet w as supplemented with these three vitamins. Bilateral eyestalk ablation was performed within 30-37 days after feeding with the experimental d iets, and weight gain and gonadosomatic index (GSI) were examined 20 d ays after each prawn's ablation. The weight gain of prawns fed with th e control diet was significantly higher (P < 0.05) than of those fed w ith diets not supplemented with vitamins A or E; however, this was no different (P>0.05) from that of prawns fed with the APM-unsupplemented diet. The highest GSI (P<0.05) was observed in prawns fed with the co ntrol diet. The control and initial prawn tissues contained higher vit amins A, E, and C than those of prawns fed with diets unsupplemented w ith vitamins A, E, or APM respectively. The present study showed the e ssentiality of supplemental vitamins A, E, and C in the diets of brood stock prawns for enhanced ovarian development.