Dietary biotin requirement for maximum growth of juvenile grass shrimp, Penaeus monodon

Abstract

A feeding trial was conducted to estimate the minimal dietary biotin requirement for juvenile grass shrimp, Penaeus monodon. Purified diets with eight levels (0, 0.2, 0.5, 1.0, 3.0, 6.0, 10.0 and 20.0 mg/kg) of supplemental biotin were fed to P. monodon (mean weight 0.26 ± 0.01 g) for 8 wk. Each diet was fed to three replicate groups of shrimp. Shrimp fed diets supplemented with biotin (0.2-20.0 mg/kg) had significantly (P < 0.05) higher weight gain, feed efficiency and protein efficiency ratio than those fed the unsupplemented control diet. Weight gain was high in shrimp fed 3.0-10.0 mg biotin/kg diet and lowest in shrimp fed ≤1.0 mg/kg diet. Hepatopancreatic biotin concentration in shrimp generally increased as dietary biotin supplementation increased. Highest hepatopancreatic pyruvate carboxylase and acetyl CoA carboxylase activity were in shrimp fed diets with 10 and 20 mg biotin/kg and 3.0 mg biotin/kg, respectively. Weight gain percentage and protein efficiency ratio of the shrimp analyzed by broken-line regression indicated that the minimal dietary biotin concentration in growing P. monodon is 2.0-2.4 mg/kg.