The Effects of Different Protein Sources On the Survival of Grass Shrimp, Penaeus Monodon (Fabricius, 1798) Larvae From Zoea To Postlarva (Decapoda, Natantia)

Abstract

Two feeding trials were carried out with Penaeus monodon larvae in a small-scale system at a density of 100 individuals l -1 from zoea I to postlarva V in order to determine the effects of dietary protein quality (white fish meal, krill meal, and soybean meal) on survival, digestive enzyme activities, and protein digestibility in vitro. Zocae fed diet C, containing 41.5% krill meal, and 20% soybean meal, had a higher survival than those fed diet A, containing 45% fish meal and 26.5% krill meal, and diet B, containing 15% fish meal, 26.5% krill meal, and 20% soybean meal. In mysid larvae, however, diet A gave the highest survival. In order to set up the feeding regime for P. monodon larvae, diets A, B, and C were used alternatively to feed zoeae and mysids. Zoeac fed diet C and mysids fed diet A had the highest survival. Using whole zoeae, mysids, and postlarvae tissue as the reference protein, there were no significant differences in essential amino acid index (EAAI) of the three experimental diets containing different protein sources. The digestive enzyme extracted from zoeac had a higher in vitro protein digestibility than those extracted from mysids. The activity of total protease was low during the nauplius stage and peaked at zoea II and mysis II. Also, the activity of α-amylase was low during the nauplius stage and peaked at zoea III and mysis II.