Common snook (Centropomus undecimalis) juveniles maintained at high temperature and brackish water improve growth, osmoregulation, and antioxidant responses

The study evaluated the interactions between temperature (25 and 28 °C) and salinity (0, 15, and 32 ppt) on the growth performance, plasmatic ions, ATPases activities, and oxidative and antioxidant parameters in different tissues of common snook (Centropomus undecimalis) reared for 90 days by a 2 × 3 factorial design. The growth performance and feed conversion ratio were influenced by temperature and interaction between factors, with the best results observed in the combination between 28 °C and 15 ppt. There were effects of temperature and salinity (isolated or in interaction) for plasmatic ions, v-type H+-ATPase (VHA) and Na+/K+-ATPase (NKA) activities, and oxidative stress responses. Gill VHA (at 32 ppt) and NKA (at 0 and 15 ppt) activities were higher at 25 than at 28 °C. In the kidney, at 28 °C, the VHA (at 15 ppt) and NKA (at 32 ppt) activities were higher than at 25 °C. The VHA and NKA activities in the stomach at 28 °C and 32 ppt were higher than at the other treatments. In the intestine, the lowest activity of VHA at 25 and 28 °C occurred at 0 and 32 ppt, respectively, and the activity of NKA was highest in the interaction of 0 ppt and 25 °C. At 0 ppt, the plasmatic Na+ and Cl− values at both temperatures were decreased, and the plasmatic K+ values at 25 °C were increased. Liver thiobarbituric acid reactive substances and protein carbonyl content values were higher at the combinations of 15 ppt and 25 °C and 32 ppt and 28 °C than at the other interactions. Liver antioxidant responses (glutathione-S-transferase, glutathione peroxidase, non-protein thiols, and superoxide dismutase) were higher at 15 ppt than other salinities at both temperatures. In conclusion, the improved growth, osmoregulation, and antioxidant responses were found to be higher at 28 °C and 15 ppt.