Evaluating the effects of dietary bergamot essential oil supplementation on growth performance, blood parameters, and antioxidant responses in common carp Cyprinus carpio juveniles

Citrus essential oils are utilized as phytogenic feed additives. The current study investigated the effects of bergamot essential oil (BEO) supplementation in fish feed on growth performance, hematological and biochemical parameters, and antioxidant activities of juvenile common carp Cyprinus carpio. All groups (control, 0.2%, 0.4%, and 0.8% BEO) were designed in triplicate. The fish were fed these doses twice daily for 60 days. The 0.2% BEO concentration was the most effective in enhancing fish growth, as evidenced by the highest relative and specific growth rate. No significant differences were observed in the hematological parameters in the experimental groups (p > 0.05). Compared with the control group, positive effects of BEO feed supplementation on serum biochemical parameters were observed in all groups, especially in the 0.2% BEO group. Although there was no statistically significant difference in catalase enzyme activity, antioxidant activity as indicated by superoxide dismutase and glutathione peroxidase antioxidant enzyme activities significantly increased in the 0.2% and 0.4% BEO groups (p < 0.05). In conclusion, these findings suggest that in all BEO groups, especially in the 0.2% and 0.4% concentrations, BEO could enhance growth performance, health, and cellular defense mechanisms in common juvenile carp, making BEO a valuable additive in fish feed.