Improving ornamental fish welfare during commercial transport

Millions of ornamental fishes undergo transport every year and as a result can experience high levels of stress. Previous research has focused on maintaining good water quality during transport; few studies have considered how the transport environment might be manipulated, e.g. using water conditioners or enrichment to enhance fish welfare. We investigated whether a commercial water conditioner (containing Aloe vera) or environmental enrichment could improve the welfare of variatus platy (Xiphophorus variatus) during commercial transport. Firstly, water conditioner was added to transport bags for either long (Singapore to Scotland, > 30 h; n = 16 bags of fish with and without water conditioner) or short (wholesaler to retailer within Scotland, < 9 h; n = 11) commercial transports. Secondly, enrichment was added to transport bags for short (< 9 h; n = 12 bags with and without enrichment) commercial transports. Behaviour, mortality and body injuries of platys were monitored on arrival at their destinations. No differences in mortality or body injury were seen between treatments and controls; mortality remained low throughout (<5%). Following long-haul transport, platys shipped with water conditioner showed less erratic swimming and were less aggressive during recovery. Addition of water conditioner during the shorter transport also resulted in less erratic swimming behaviour, although here an increase in chasing behaviour was seen during recovery. These studies indicate that the use of water conditioners and enrichment warrants further research, particularly within transport chains were higher levels of mortality exist.