Impact of "bumper car" disease on the North American lobster fishery

Although 1993 landings of lobsters were valued at $300 million in Canada and $210 million in the United States, postharvest losses are 10-15% annually. "Bumper car" disease of lobsters caused by the scuticociliate Anophryoides haemophila, can be significant in coldwater impoundments. Although outbreaks occur more frequently and with greater severity, the epidemiology and economic impact of "bumper car" disease are not well documented. The ciliates are maintained in cell-free, defined medium at 5 degree C. Cultured ciliates require longer and more parasites to kill lobsters than those transmitted by intrahaemocoelic injection from lobster to lobster. Horizontal transmission likely occurs across gills of lobsters. Several licensed disinfectants and chemotherapeutants are efficacious against A. haemophila in vitro. Additional to indirect fluorescent antibody testing utilizing monoclonal antibodies prepared to sonicated ciliates, parasites are detected with oligonucleotide probes based on ssu-rDNA of A. haemophila. The prevalence of A. haemophila in wild-caught lobsters should be reevaluated with more sensitive and specific diagnostic tools. A definition of healthy versus ciliate-infected lobsters is being prepared, based on haematology and clinical chemistry of haemolymph. Our novel bar-coded labelling system for aquatic organisms facilitates experimental design and randomization protocols of lobsters. The model of "bumper car" disease will aid study of health and infectious disease processes of lobsters.