Oxidative stress in tench, Tinca tinca (L.), caused by sport fishing

Summary The effects of angling on oxidative/antioxidant systems in tench ( Tinca tinca ) were tested to determine oxidative stress. A total of 50 tench (1‐year‐old, 16 cm TL ) were captured in a 1800 m 2 pond and transferred to an aerated tank for sampling (n = 5) 3 h later. Forty‐five of the tench were stocked in a 50 m 2 pond and recaptured (n = 5 per sample) 2, 7, and 17 days thereafter. The remaining five tench were used as the control. Superoxide anion, superoxide dismutase ( SOD ), and lipid peroxides were determined in the liver, brain, white muscle, and gills. Results indicated that there were changes in the liver superoxide levels 2 days after angling, but there were no enzyme responses or increases in lipid peroxidation. Superoxide anion values returned to normal 7 days after capture. The conclusion is that tench can recover within a short period of time from the oxidative stress caused by angling.