Haematological assessment of the effects of the anaesthetic MS 222 in natural and neutralized form in three fresh water fish species: haemoglobin electrophoresis, ATP levels and corpuscular fragility curves

The effects of MS 222 and neutralized MS 222 anaesthesia on haemoglobin electrophoresis, erythrocyte adenosine triphosphate (ATP) levels and corpuscular fragility curves were studied in Cyprinus carpio, Sarotherodon mossambicus and Salmo gairdneri . Haemoglobin electrophoresis showed no significant intra-species differences in the percentage composition of the various fractions for any concentration of MS 222 and neutralized MS 222 used. Significant interspecies differences were, however, still observed. ATP levels showed intra and interspecies differences ascribed to the response of the fish species to MS 222-induced stress and not to actual changes in erythrocyte ATP concentrations. Differences were also observed in corpuscular fragility curves for all three species when using MS 222 or neutralized MS 222 compared to curves obtained without the use of the anaesthetic, but the mechanisms involved are not clear.