Combined Effects of Temperature and Salinity Affect the Surviv-Al of Asian Green Mussel (Perna viridis) through Digestive and Antioxidant Performance

Abstract

Changes in temperature and salinity of the marine environment fluctuate continuously, and the effects of these changes on shellfish survival are significant. In this study, the survival rate of adult Asian green mussels (Perna viridis) was measured after short-term treatments (7 days) for a range of temperature (20 °C, 25 °C, 30 °C) and salinity (23‰, 28‰, 33‰). The digestive (amylase, lipase, trypsin and pepsin activities) and antioxidant performance (SOD and GPX gene expression; SOD, GPX and CAT activities; GSH and MDA Concentration) were measured and MANOVA results were obtained using a generalized linear model between certain factors (temperature (T), salinity (S) and temperature × salinity (T × S)) and survival rate. Both T and T × S significantly affected the survival rate of Asian green mussels. The overall relationship between the survival rate of P. viridis and T and S within the experimental range can be summarised by the equation: ln(Survival rate) = 54.9282 − 2.5627 × T − 3.6180 × S + 0.1857 × T × S + 0.0156 × T2 + 0.0520 × S2 − 0.0012 × T2 × S − 0.0023 × T × S2. The optimal temperature–salinity combination was 23.698 °C/30.760‰. T, S and T × S all had a significant impact on amylase and lipase activities of Asian green mussels. In the hepatopancreas, gill, mantle, adductor muscle, gonad and foot tissues of Asian green mussel, the SOD and GPX gene expression were responsive to temperature–salinity changes. The antioxidant performance of the combinations far from the optimal temperature–salinity combination were significantly improved. Our results suggest that combined temperature and salinity effects have a regular impact on the survival of Asian green mussels and that there is a link between survival and digestive and antioxidant performance.