Effect of Dietary Protein Levels on Growth Performance, Feed Utilization and Economical Evaluation of White Shrimp Larvae Litopenaeus vannamei

The present experiment was conducted to investigate the effects of five different protein levels (25%, 30%, 35%, 40% and 45%) on growth performance, feed utilization, survival and economic analysis of whiteleg shrimp, Litopenaeus vannamei larvae. The experiment was performed indoor at Invertebrate laboratory of National Institute Oceanography and Fisheries (NIOF), Suez governorate -Egypt. The experiment was carried out in 15 rectangular tanks (66*47*44 cm, 50 L) of reinforced with water salinity 20 ppt for 90-days. Triplicate groups of shrimp larvae with an initial weight 0.002g were fed twice a day at a feeding ratio of 14% from body weight (nit weight) and re-adjusted gradually to 5% at the end of the experiment. The results observed that the highest significant(p < 0.05) weight gain (%), specific growth rate, best feed conversion ratio values were reported with the shrimp fed 35% protein group. The same trend was observed for protein utilizing efficiency. Protein efficiency ratio was significantly affected by dietary protein level. The present results revealed that dietary crude protein of 35% for L. vannamei larvae may optimum in terms of growth performance, feed utilization and economic evaluation under these experimental conditions.