28th ANNUAL EASTERN FISH HEALTH WORKSHOP April 21-25, 2003 Prevalence Of Type E Botulism In Fish In The Lower Great Lakes Rodman G. Getchell 1, Gregory A. Wooster 1, William J. Culligan 2, and Paul R. Bowser 1 1 Aquatic Animal Health Program, Cornell University, Department of Microbiology and Immunology, Upper Tower Road, Ithaca, New York, 14853; 2Dunkirk Fisheries Research Station, New York State Department of Environmental Conservation, Dunkirk, New York, 14048 Botulism has been documented in waterfowl during several mass mortality events on Lake Erie in 1999-2002.  This project is focusing on the role of fish in these outbreaks.  The specific objectives of the project are to determine the prevalence of Clostridium botulinum in apparently healthy, moribund, and dead fish in areas of confirmed outbreaks of avian botulism and unaffected areas within the Lower Great Lakes.  We are also quantifying the amount of C. botulinum and toxin in carrier fish.  In a cooperative effort with the New York State Department of Environmental Conservation, we are collecting fish from both Lake Erie and Lake Ontario.  The focus is on species of fish that have died in recent fish kills such as freshwater drum, smallmouth bass, and round goby.  Scheduled collections of these species of fish, as well as sampling during fish kills and active outbreaks of botulism in waterfowl, have or will take place.  Standard necropsies are being performed on all fish sampled including skin scrape, gill clip, and bacteriological culture of the kidney.  Tissue samples that are being archived for real-time PCR assay of the type E botulinum toxin gene include liver, blood, and intestinal contents.  Those samples that test positive for C. botulinum also will be assayed for toxin by the traditional mouse bioassay and the number of bacteria present will be enumerated by quantitative PCR.  We hope to better understand the circumstances under which fish-eating birds can become intoxicated with type E botulism from eating live or moribund fish.  Prevalence data from the 2003 field season will be presented. Return to 28th Annual Eastern Fish Health Workshop Return to Leetown Science Center Home Page