Effectiveness of the Food-Safe Anaesthetic Isobutanol in the Live Transport of Tropical Spiny Lobster Species

Abstract

The strong demand for live spiny lobsters in Asian markets is being met by long-distance airfreight. Holding lobsters out of water during transportation often results in mortalities due to the accumulation of metabolites, especially ammonia. This study examined the potential to improve the survival of tropical lobster species exported from India through the use of the food-safe aquatic anaesthetic isobutanol, both with and without cold stunning, typically used prior to live lobster transportation. The results of the study indicate that treatment with 50 ppm isobutanol in ambient seawater temperature (i.e., 28 °C) prior to simulated live transport for 22 h significantly reduces ammonia levels in the haemolymph in all four lobster species (Panulirus homarus, P. ornatus, P. versicolor and P. polyphagus) compared to lobsters treated with cold stunning (i.e., 16.5 °C) with and without 10 ppm isobutanol. Cold stunning at 16.5 °C combined with 10 ppm isobutanol reduced ammonia levels compared to cold stunning alone only in P. ornatus. All experimental lobsters were returned to ambient seawater after simulated transport and were alive after 48 h. These results indicate that isobutanol has the potential to be used to suppress metabolism during the live transport of tropical lobsters and to reduce mortalities during live transport.