Use of eugenol, benzocaine or salt during the transport of panga, Pangasianodon hypophthalmus (Sauvage, 1878): Effects on water quality, haematology and blood biochemistry

Sedatives and salt have been used to mitigate the effects of stress during the transport of live fish. This work evaluates the use of benzocaine, eugenol or salt during the transport of panga. Juveniles (22.9 ± 5.3 g) were transported for 5 h in 15‐L bags containing 6 L of water (one juvenile per litre). Seven transport treatments containing four repetitions (control 0 mg/L; 5 and 10 mg/L of eugenol; 5 and 10 mg/L of benzocaine; 4 and 8 g/L of salt) and a basal pre‐transport treatment were evaluated. No mortality was observed during the experiment and no differences were found among treatments for dissolved oxygen, haematocrit, haemoglobin and total protein. Immediately after transport, lower ammonia levels were found using 5 mg/L of benzocaine and 10 mg/L of eugenol; a lower glucose concentration was observed for the fish submitted to 5 mg/L of eugenol; and a higher triglycerides were observed for the fish submitted to 4 g/L of salt. After 24 h post‐transport, the highest glucose level was for 8 g/L of salt, while the highest cholesterol level was for 4 g/L of salt. After 48 h post‐transport, the lowest triglyceride level was for 5 mg/L of eugenol. In conclusion, we recommend adding 5 mg/L of benzocaine or 10 mg/L of eugenol to water to reduce ammonia excretion during panga transport.