Effect of dietary protein level on its in vitro and in vivo digestibility in the tiger shrimp Penaeus monodon (Crustacea: Penaeidae)

摘要

Protein being the most important and expensive nutrient in shrimp feed, determination of its appropriate level in relation to the digestive capacity of shrimp is essential in order to make the feed cost effective as well as to minimize the nitrogenous waste excretions. Six diets having different levels of crude protein (30-41%) were investigated by in vitro digestibility method using the homogcnate of hepatopancreas (digestive proteases) of tiger shrimp Penaeus monodon. Peak digestibility of dietary protein was observed at 3 hours incubation. Maximum digestibility of protein (69.19%) was recorded with diet having 35.28% protein. The in vivo results in tiger shrimp (2.0g) also showed that the weight gain in the shrimp was also highest at this dietary protein level. The average apparent protein digestibility was highest (76.02%) in animals fed with diet having 35% crude protein. The results of the study suggested that dietary protein for P.monodon can be lowered to 35%, considerably reducing the cost of the feed and making it more environmental friendly.