Abstract
The objective of the present study was to investigate the importance of the antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), and glutathione peroxidase (GPX) in the defense against lipid and protein oxidation in spawn from female brown trout, Salmo trutta m. trutta L. affected by ulcerative dermal necrosis (UDN). UDN induced increased lipid and protein oxidation levels. The current results show that UDN infection led to oxidative stress with the inhibition of antioxidant defense mechanisms. The inhibition of glutathione defense system activity might be responsible for this failure in cellular antioxidant defenses. UDN induces irreversible changes in pro- and antioxidative function which effected decreased spawn survival as well as reductions in spawning efficiency.