Aspects of ornamental fish aquaculture: Implications for detection of exotic viral pathogens in imported ornamental fish

Abstract

Recently viral agents have emerged as the source of significant disease and mortality in fish worldwide. It has long been recognised that the movement of ornamental fish through exporting and importing practices provides a transmission pathway for the introduction and establishment of exotic viral pathogens. Aspects of ornamental fish aquaculture are reviewed with a focus on the disease risks associated with Australia’s importation of live ornamental fish. The viral agents Megalocytivirus and Cyprinid herpesvirus-2 (CyHV-2), which represent significant exotic pathogens to Australia, are detailed through the use of case studies which confirm that the disease risks posed by the importation of ornamental fish are genuine. These cases highlight the need for investigation to determine the prevalence of these viral pathogens in post-quarantine situations such as aquatic retail outlets which has important implications for policy and management. The potential for the use of molecular diagnostic tools such as standard and quantitative polymerase chain reaction (PCR) for the detection of exotic viral pathogens is proposed as a way of addressing the apparent inadequacies of Australia’s current quarantine program whereby the occurrence of inadvertent disease release is unacceptable.