Effects of temperature and salinity on the biological responses of mussels (Mytilus galloprovincialis).

In this study the effects of temperature and salinity on some stress indices are evaluated in mussels (M. galloprovincialis) from the Lagoon of Venice (Italy). The aim is to detect and evaluate possible response modulation between organisms from two differently polluted sites. In the first experiment sets, mussels are exposed to water temperatures of 15°C and 25°C, in the second to salinity of 26 PSU and 36 PSU. Organisms are sampled after 3 and 6 days and their biological response evaluated at biochemical, cellular and physiological level. Results showed that the applied biomarkers are suitable, as a whole, to demonstrate the impaired well being of mussels of different origin. Aldehyde dehydrogenase activity is always insensitive to temperature, and to salinity in the most polluted organisms. Enzyme response is always influenced by different time exposure of both temperature and salinity, except for salinity in less polluted mussels. Catalase activity is always unaffected by salinity, and by temperature in the less polluted mussels. This enzyme activity is influenced by time exposure of both temperature and salinity in the polluted mussels, thus showing the different behaviour of the two populations. Neither temperature nor salinity, nor time of exposure (except for salinity in the less polluted mussels) influenced the results from the neutral red test. Survival in air was always controlled by temperature, salinity, and time of exposure. This work was supported by CORILA.