Effect of MS-222 and Benzocaine to the Transportation of Siamese Fighting Fish (Betta splendens Regan)

Abstract

Acute toxicity of MS-222 and benzocaine to Betta splendens Regan averaging 1.48 ± 0.30 g in weight were studied. By using Litchfield and Wilcoxon method, the results showed that the 96 hr LC50 with 95% confidence intervals of MS-222 and benzocaine were estimated to be 176 (172.89 - 179.17) ppm and 202 (199.21 - 204.83) ppm, respectively. The responding reaction could be divided into 4 periods: sedation, loss of equilibrium, loss of reflex activity, and medullary collapse. The suitable sedation concentration of MS-222 and benzocaine for 48 hours of fish transportation were 65-70 ppm and 80-85 ppm respectively. The fish could recover from the two anaesthetics within 3 to 5 minutes. It is recommended that MS-222 and benzocaine are more suitable to be used for anaesthetizes fish during transportation and benzocaine may be preferred as it is cheaper than MS-222.