Adequacy Study of 2-Phenoxyethanol on Hypselobarbus kurali as an Anesthetic

Abstract

Hypselobarbus kurali, one of the most demanded fresh water hill stream fish belonging to the family cyprinidae. In the case of brood H. kurali, injuries inflicted to the sudden death of the fish often pose a major problem. When large brood fish are involved, it can lead to incomplete voiding of eggs and mortality in most cases. Anaesthetizing the fish is a practical option for facilitating ease of handling, improved egg yield and breeding response, besides significantly lowering brood mortality rates. In this context, detailed studies were conducted on the use of a commonly employed anaesthetic 2-phenoxyethanol, in the handling and transportation of the fresh water hill stream fish Hypselobarbus kurali. Four levels of anaesthetic were tried viz., 300, 400, 500 and 600 μL LG1. The efficacy of the anaesthetic was assessed by considering four stages of induction (I1, I2, I3 and I4) and three stages of recovery (R1, R2 and R3). In the present study, the lowest induction time (<180 sec) was observed at 500 μL LG1 and therefore, this dose was considered as the lowest effective concentration for anaesthesia in H. kurali. At 500 μL LG1, the time to reach anaesthesia stage (I3) of induction (159±13 sec) and recovery (R3) time (133±16 sec) was significantly different (p<0.05) from the other dosages 400 μL LG1 ( 193±14 sec), 300 μL LG1 ( 216±78 sec) and 600 μL LG1 (190±14 sec).