Antioxidant and immunostimulant responses in rainbow trout (Oncorhynchus mykiss) fed with cherry stem extract

Abstract

We examined antioxidant enzyme activities, immune response, blood parameters and growth performance of rainbow trout fed with different doses of cherry stem (CS) aqueous methanolic extract. Four different feeds containing CS extract in different doses, 0% (control), 0.1 (0.1% CS), 0.5 (0.5% CS) and 1% (1% CS), as treatment feeds were prepared. Fish were fed with the diets for 60 days. The results showed that superoxide dismutase (SOD) activity was significantly increased on 20th and 60th days in all CS-treated fish groups. On 40th day, only 0.1% CS fish group had an elevated SOD activity compared with that of control (p < 0.05). Catalase (CAT) was significantly increased on 20th day of the study in 0.1 and 0.5 CS-treated groups compared with control and this increase was observed in all treatment groups on 40th day. However, in all fish groups, CAT was significantly decreased on 60th day. Glutathione peroxidase (GPx) was increased on 20th day in 0.1% CS fish group and in all treatment groups on the 60th day. G6PDH showed no significant difference at the end of experiment compared to the control. Similar result to that of G6PDH was obtained on lipid peroxidation. Haematocrit values of all the CS-treated fish groups were significantly increased at the end of the study. Growth did not differ among fish groups. Results indicated that 0.1% and 0.5% CS could be used as the dietary supplementation in rainbow trout.