Effect of feed additive Stafac-500 on the growth and feed conversion for juvenile white shrimp, Litopenaeus vannamei

five diets added feed additive Stafac-500(Stafac^®)0, 20, 40, 60 or 80 mg · kg^-1 diet were conducted to determine the weight gain (WG, %), survival, feed conversion ratio (FCR) for Litopenaeus vannamei juvenile (weight 0.22 g) at indoor concrete pools(0.90 m×0.60 m×1.0 m)for 8 weeks. Groupers of 60 animals were used in each pool, in triplicate. WG of the shrimp fed five diets contained feed additive Stafac-500 were 1 105±43, 1 115±33, 1 150±22, 1192±53 and 1 272±33, respectively; and FCR were 1.56±0.11, 1.51±0.02, 1.45±0.01, 1.42±0.10 and 1.49±0.02, respectively. The result showed that shrimp fed trial diets contained feed additive Stafac-500 40, 60 and 80 mg · kg^-1 diet superior to the control. However, dietary Stafac-500 (Stafac^®)did not affect the whole-body composition among shrimp fed with the various diets.