Evaluating Neem Seed Powder (Azadirachta indica) as an Anesthetic for Common Carp (Cyprinus carpio) Across Various Weight Groups ‎

Abstract

A natural alternative anesthetic, such as neem (Azadirachta indica) seed powder, may offer safer and more environmentally friendly practices in aquaculture. This study aims to assess its efficacy and safety on common carp (Cyprinus carpio) across different weight groups. Seven groups of common carp weighing between 20 and 89 g were exposed to neem seed powder. The time required for each fish to attain stage 3 of anesthesia (total loss of equilibrium) and to recover were recorded. The largest group of fish (80–89 g) was selected for subsequent blood tests due to its sensitivity to the anesthetic action of the neem seed powder. The results showed that the lowest-weight fish group (20–29 g) required more time to attain anesthesia at all dosages (12.98–21.13 min) compared to the maximum weight group (80–89 g) (8.83–16.85 min). Recovery times were not significantly impacted by varying anesthetic doses, but shorter recovery times were associated with large fish size. Although neem seed powder at concentration of 5–10 g·L^-1‎ significantly affected blood parameters, such as decreased red blood cell count and increased white blood cell and blood glucose levels, no fish morbidity or mortality was observed. Therefore, neem seed powder (up to 10 g·L^-1) can be safely and effectively used to sedate common carp as an alternative to synthetic chemical anesthetics.