Toxicity effect of copper on histopathology of oreochromis niloticus liver with diet of lactic acid bacteria

Harmful effects of heavy metals are myriad. Copper (Cu) from the activity of human and industrial waste contaminates water bodies and affects the aquatic animals. Our study confirmed the in vitro probiotics potential of lactic acid bacteria (LAB) against Cu toxicity, but further investigation is necessary for gaining insights into the related protection mode. Therefore, in this study, we investigated the protective effects of the potential probiotics LAB against waterborne Cu exposure-induced toxicity in the freshwater fish Oreochromis niloticus. Fish (average weight: 82.15±15g) were allocated to eight groups (variations Cu concentrations 0, 0.75, 1.5 and 3 ppm and feed diets (containing probiotics LAB and commercial feed)) for 2weeks. Probiotics LAB supplemented diet was provided one time daily. Histopathology of hepatocyte in fish liver were measured at the end of the study. When the fish were exposed to Cu, dietary supplementation of probiotic LAB effectively decreased edema and necrosis hepatocyte of fish liver. Therefore probiotics LAB may be a novel dietary supplement for enhancing growth performance and preventing Cu-exposureinduced toxicity in fish in aquaculture and aquatic products.