Antioxidative and immunological response of shrimp Litopenaeus vannamei to combined stress of acute cold exposure and waterless duration: Implications for live transport

High mortality is a common phenomenon for live transport of shrimp Litopenaeus vannamei, and the biochemical mechanism underlying mortality remains incompletely known. This investigation explored the effect of combined stress of acute cold exposure (AC) and waterless duration (WD) on survivability, oxidative stress, antioxidative and immunity defence responses, and histological impairments. The survival profiles showed no significant difference between normal control (NC) and AC groups. The shrimps exposed to AC + WD stress, however, exhibited significantly higher mortality (p < 0.05) since 6 h afterwards, and the median survival probability was observed at 10.46 h. Overall, both the homeostasis of antioxidative and immunological response were disturbed in a duration time-dependent manner, and the impairment on hepatopancreas was observed. Significantly, the indicators of total haemocyte count (THC), viable haemocyte count (VHC) and peroxidase (POD) decreased while the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), phenol oxidase (PO), alanine transaminase (ALT) and aspartate transaminase (AST) increased (p < 0.05). Together, correlation analyses indicated that high mortality of L. vannamei was resulted from the disorder of antioxidative and immunological response. This study deepens our understanding into mortality of L. vannamei during waterless live transport.