IMPORT, QUARANTINE, AND DISEASE TESTING OF THE AFRICAN LONGFIN EEL Anguilla mossambica IN MAINE, USA

Global trade in immature glass eels or elvers captured from the wild is an integral component of eel aquaculture.  Consequently, in many regions of the world one or more non-native eel species are imported for stocking aquaculture farms.  The two primary risks to native stocks from this activity are considered to be escapement and disease.  While escapement can be minimized or even eliminated with readily implemented physical barriers, managing disease risk may require a period of quarantine and disease testing following import, specific to regional concerns and regulations.  As part of a feasibility trial, immature African longfin eels (Anquilla mossambica) were imported into Maine USA and stocked into a closed-containment recirculating aquaculture system for quarantine while disease testing was carried out.  During the quarantine period all effluent was filtered to retain particles greater than 50µm, followed by ultraviolet light disinfection at a dose exceeding 180 Mj/cm².  Effluent discharge rate was limited to less than 25 l/m, and solids were stored and disinfected in a closed tank for off-site disposal.  Within 1 week of transport 150 glass eels were sampled for disease screening at a level sufficient to detect pathogens at an assumed 2% prevalence.  Parasitology was conducted to screen for the swim bladder nematode Anguillicola papernai.  Virology was conducted on CHSE, EPC, GF-1, EK-1, and SSN cell lines, with mandatory reporting of cytopathic effect.  Molecular screening was used for detection of Franciscella sp. and for A. papernai.  Preliminary results showed no presence of any pathogens of regulatory concern.