Efficacy of Copper Oxide Nanoparticles Dietary Supplementation on Gilthead Seabream Growth, Health Status, Immune-Oxidative Response, Histomorphology of Intestine and Hepatopanceas

This study explored the potential of dietary supplementation of copper oxide nanoparticles (Cu-NP) and their effects on performance and health of gilthead seabream (Sparus aurata) fingerlings. Fish (N=270, 28.56 ± 1.205 g) were randomly distributed in 18 hapa in triplicate representing six treatments. Control group (Cu-NP0), (Cu-NP0.25), (Cu-NP0.5), (Cu-NP1.0), (Cu-NP1.5) and (Cu-NP2.0) in which fish received 0, 0.25, 0.5, 1.0, 1.5 and 2.0 mg/kg Cu-NP respectively for 90 days. Results revealed dietary supplementation of fish with Cu-NP can improve growth and feed utilization indices compared to Cu-NP0 (P < 0.05), with the best results displayed in Cu-NP1.0. A significant improvement of hematobiochemical parameters and lipase activity was exhibited in Cu-NP1.0 whereas the lowest values of these parameters were showed in Cu-NP2.0. Catalase, superoxide dismutase, and malonaldehyde showed a dose dependent improvement with the increase of Cu-NP dose and the highest values recorded in Cu-NP2.0 whereas the lowest malonaldehyde activity was observed in Cu-NP1.0. Fish exposure to 1 mg/Kg Cu-NP significantly increased phagocytic activity, phagocytic index, lysozyme activity and immunoglobulin M content. Compared to Cu-NP0, a significant dose-dependent elevation in the expression of apoptosis related gene (HSP70) and innate immune response gene (IL1β) whereas the maximum expression of growth regulating gene (ILGF-1) displayed in Cu-NP1.0. Intestinal and hepatopancreatic tissue histomorphology was improved in Cu-NPs-treated groups in ascending manner associated with increased doses then it was deteriorated with Cu-NP2.0 dose. Conclusively, dietary supplementation of gilthead seabream with 1 mg/kg diet Cu-NP improved growth performance, general health, antioxidant activity and immune response.