Some observations on the use of MS 222 Sandoz with grey mullet (Mugil chelo Cuvier)

Two trials, each using grey mullet, were carried out to investigate the use of the anaesthetic, MS 222 Sandoz, in the handling and transportation of fish. The first trial examined the effect of using various concentrations of MS 222 Sandoz and it was concluded that concentrations of between 1: 75 000 and 1: 100000 were sufficient to tranquillize the fish for pre-transport handling. A further trial using the anaesthetic at a concentration of 1: 100 000 and with a fish biomass of 50 g/1 demonstrated that tranquillized fish could safely be held at this density for a 48 h period. It was concluded that the use of anaesthetic such as MS 222 Sandoz could aid handling and loading operations and induce quiescence for a transportation period of up to 48 h duration.