Studying the Influence of Copper on the Growth Behavior, Antioxidative Status, and Histology of the Intestine and Liver of Striped Catfish (Pangasianodon hypophthalmus).

Microelements are well recognized as an essential approach in the field of aquaculture nutrition. Thus, this study aimed to evaluate copper (Cu) inclusion (0, 0.5, 1, and 2 mg/kg) on Striped catfish performances. Fish fed the Cu-incorporated diets for 60 days, then their growth behavior, antioxidative capacity, and intestinal and liver histological features were evaluated. The results showed a marked enhancement in Striped catfish's growth behavior fed 1-2 mg/kg of Cu, as shown by the final weight, weight gain, and specific growth rate. The feed and protein efficiency ratios were significantly affected by Cu in a dose-dependent manner. The highest level of Cu was accumulated in the whole body, muscle, liver, and gills of fish fed 2 mg/kg of Cu. The carcass composition of Striped catfish showed higher protein content in groups received 0.5, 1, and 2 mg/kg Cu in a linear and quadratic manner (p=0.001). The ash content was quadratically increased in Striped catfish fed 2 mg/kg Cu (p=0.001). However, no marked effects were observed on the moisture and lipid contents and the somatic indices (p>0.05). The incorporation of Cu showed meaningfully increased superoxide dismutase, catalase, and glutathione peroxidase but decreased malondialdehyde level in Striped catfish. The villous height exhibited visible growth and branching with increased doses of Cu without a significant increase in the goblet cells. No abnormal features were observed in the liver and hepatocytes of fish treated with Cu. It can be concluded that Cu is required at 1-2 mg/kg for better performances of Striped catfish.