Effects of different levels of energy and protein sources on the growth performance, feeding, survival rate and the chemical body composition of juvenile pacific white shrimp (Litopenaeus vannamei)

The present study was carried out in order to establish an economical effective diet for the pacific white shrimp in the southern part conditions of Iran. Three dietary energy levels (E1=262, E2=312, E3=362 Kcal 100 g(-1) diet) and 6 ratios of fish meal (FM): soybean meal (SBM) [(P1=100% FM+ 0% SBM), (P2=80% FM+ 20% SBM),(P3=60% FM+ 40% SBM), (P4=40% FM+ 60% SBM), (P5=20% FM+ 80% SBM),(P6=0% FM+ 100% SBM)], 18 experimental diets were prepared. Completely randomized design was used to assign 54 polyethylene 300 litre round tanks provided by aeration and was stocked by 19 juvenile shrimp as 3 replicates to each treatment. Shrimps average weight was about 0.77 g at the start. After 56 days culture period, maximum growth and nutritional performance were observed in the P6E1 and P5E1 treatments. In addition, the highest survival rate of the shrimps was observed in the P1E1, P1E2, P3E3 and P5E3 treatments. Results indicated that protein, fat, fiber and ash contents of carcase were significantly affected by the treatments (P<0.05). Results of the present study suggest the replacement possibility of at least 80% of dietary fishmeal by soybean meal in the diet of pacific white shrimp in the conditions of southern part of Iran.