Effects of stocking density of the white shrimp Litopenaeus vannamei (Boone) on immunities, antioxidant status, and resistance against Vibrio harveyi in a biofloc system

Abstract Determining optimum stocking density of the white shrimp Litopenaeus vannamei (Boone) is a big concern for shrimp farmers. However, few studies have assessed the influence of stocking density on the antioxidant status, immunology, digestive enzyme activities, and growth performance of white shrimp in biofloc systems. In this study, these parameters of white shrimp in a biofloc system were compared at three stocking densities: 300 orgs m −3 as low stocking density (LD), 400 orgs m −3 as medium stocking density (MD), and 500 orgs m −3 as high stocking density (HD). The feed conversion ratio in the LD group was significantly lower than that in the MD and HD groups ( P P Vibrio harveyi . Results of this study indicated that the immune status and welfare of white shrimp can be seriously impaired in the HD condition (i.e., ≥500 m −3 ) in biofloc systems. These findings can be used to determine suitable stocking densities in the white shrimp farming industry using the biofloc system.