The role of Saccharomyces cerevisiae to alleviate copper sulfate toxicity in Cyprinus carpio

This study aimed to determine the role of Saccharomyces cerevisiae in alleviating copper sulfate toxicity in carp fish and by evaluating Acetylcholinesterase (AChE) activity and histopathological alteration in gills and brain with determined the severity of lesions in the gills by semi-quantities analysis. Sixty fish were divided into four groups first was a control group fish in the second group were exposed to CuSO4 0.53 mg/L, in the third group fish were treated with yeast 5 g/ kg ratio and the fourth group fish treated with yeast and exposed to CuSO4. At the end of the experiment (56 days) it was observed that there was a significant decrease in the AChE activity in the second group, while this activity was improved significantly in the fourth group. The histopathological alteration in the brain was variable in the severity from infiltration of inflammatory, edema, and central chromatolysis of neuron cell bodies. At the same time, the lesions in the gills include edema, congestion, hydropic degeneration, hyperplasia in the mucus cells with shortening in the secondary gill filaments shaped like a drumstick, necrosis, and cartilage disruption. The semi-quantities lesions analysis in the gills classified them as mild, moderate, severe, and irreversible lesions. These lesions in both brain and gills were mild in severity in fish of group fourth. These studies conclude that the activity of AChE is a biological indicator for copper sulfate neurotoxicity and also causes damage to the brain and gills, and yeast is a bio adsorbent agent for coppe