Ontogenetic changes of innate immune parameters from eggs to early postlarvae of white shrimp Litopenaeus vannamei (Crustacea:Decapoda)

Abstract

To date, little is known about the immune system during early ontogeny for crustaceans with high commercial value, such as white shrimp (Litopenaeus vannamei). The aim of this study was to characterize several immunological parameters during ontogeny (from eggs to early postlarvae) of L. vannamei under farming conditions. Phenoloxidase activity showed the highest peak 3.6±0.4×10−2U μg−1 at the first nauplius stage, followed by a continuous decrease until dropping to 14% of the peak value in early postlarval (PL) stages. Superoxide dismutase activity reached the highest peak 9.9±0.3×10−3Uμg−1 after metamorphosis to the protozoea stage, then to half that value after metamorphosis to mysis stage and kept dropping until reaching a minimum of 0.5±0.4×10−3Uμg−1 in PL stages. In larval stages peroxidase activity showed a maximum of 2.5±0.4×10−6Uμg−1 after metamorphosis to mysis, and a gradual increase was observed in PL stages until attaining the highest value 4.6±0.8×10−6Uμg−1. Generation of superoxide anion showed a progressive increase after spawning in an evident relationship with growth, reaching the highest value of 7.0±0.4×10−6Uμg−1 in PL-7. To our knowledge, this is the first study that characterizes immunological parameters through the first stages of ontogeny of L. vannamei under farming conditions.