Assessment of the physiological markers, oxidative stress and neurotoxic effects of nematode Anisakis sp. on the Luciobarbus callensis (Teleosts, Cyprinids) in northeast of Algeria

Our study focused on the effect of parasites on the antioxidant system and their neurotoxic effect in Luciobarbus callensis (Teleosts, Cyprinids). In this context, cellular biomarkers, acetylcholinesterase (AChE), catalase (CAT), molecules H2O2 as well as morphophysiological markers (condition factor (FC), hepatosomatic index (HSI), splenosomatic index (SSI), viscerosomatic index (VSI) were analyzed in fish infested with L3 larvae of Anisakis sp., nematodes of marine organisms, captured in Lake Oubéira (Algeria). The results showed a significant decrease in AChE activities in the heart (68 % p < 0.05) and muscles (81.55 % p < 0.05) in infested fish compared to those recorded in reference fish. In contrast, splenic AChE levels were significantly induced. CAT levels were significantly decreased in the spleen (73 % p < 0.05) and intestine (56 % p < 0.05) of fish parasitized by Anisakis sp. compared to healthy fish. HSI and SSI were significantly higher in healthy fish. On the other hand, Anisakis sp. had no significant effect on FC and VSI at the time of sampling. This study suggests that antioxidant defense disorders (CAT), due to a direct inhibitory action of nematode toxic products on this molecule and an increase in ROS production in these animals, leading to a high pro-oxidant state (H2O2), causing neurological effects (AChE) with enlargement of the spleen and liver of infested barb. In this regard, monitoring the effect of parasitic infections on physiological and biochemical marker profiles can be a crucial means of assessing fish health under natural conditions; to ensure the conservation and sustainability of aquatic biodiversity, including fish farming and artificial production