Effects of replacement of fish meal with peanut meal in practical diets on growth and amino acid profile of Pacific white shrimp Litopenaeus vannamei

A 56 d feeding-trial was conducted to evaluate the effects of replacement of fish meal with peanut meal in practical diets on growth performance and amino acid profile of Pacific white shrimp Ltopenaeus vannamei.Six isonitrigenous diets were formulated to contain 40% protein and 6.5% lipid.Fish meal contained in the diets at a rate of 36% was replaced by peanut meal at six inclusion levels of 0,10%,20%,30%,40% and 50%(diets 1-6).The shrimp juveniles with 0.246 g mean initial body weight were distributed in 260 L tanks at a rate of 30 shrimp per tank,using a completely randomized design with six treatments and three replicate groups per treatment,and fed four times daily.Survival,growth,feed conversion ratio(FCR) and protein efficiency ratio were not significantly affected by the dietary treatments in 4 weeks.However,in 8 weeks,weight gain decreased with increasing inclusion of peanut meal.The shrimp fed diet 6 had significantly lower weight gain(1932.4%) than those fed other experimental diets.Survival and FCR were no significantly different among the treatments.However,protein efficiency was significantly lower(2.01,2.09 and 2.08,respectively) for diet 4,5,and 6 than that in the control,when replacement of fish meal by peanut meal inclusion up to 30%.Amino acids profile of shrimp was varied with replacement fish meal by peanut meal.Content of methionine in the shrimp decreased with increasing dietary inclusion of peanut meal.For musclular arginine and methionine,however,there was decrease with increase in inclusion levels of peanut meal.Based on WG,PER,survival and amino acid content of the shrimp,it was feasible to replace fish meal with peanut meal at level of 20% or so.