CHARACTERIZATION OF A PASTEURELLA SPECIES IMPLICATED IN A MASSIVE WHITE PERCH MORTALITY,
FORT DETRICK FREDERICK MD
Pagination or Media Count:
The organism isolated from moribund white perch and identified as a Pasteurella species by the Federal Fish Disease Laboratory during the 1963 massive mortality in Chesapeake Bay has been further characterized in our laboratory. It is antigenically distinct from other Pasteurella species and a number of fish and human pathogens that it resembles morphologically and physiologically. At this time it is felt that there is sufficient justification to retain it in the genus Pasteurella and the species name, piscicida, is suggested. The organism causes a lethal acute septicemia in white perch following injection of 1,000 or more cells, but it will not cause infection of mammals experimentally. It is not fastidious in its growth requirements other than being obligately halophilic, but has a narrow range of salt, pH, and temperature tolerance it does not survive long in spent media or brackish water. Antibodies to this pathogen have been detected in white perch from the rivers of the upper western shore of Chesapeake Bay 2 years after the massive mortality. The possibility is suggested that temperature stress on wintering fish and human sewage pollution may have played a part in the massive mortality. In addition, serologic evidence is presented that white perch in polluted rivers may be infected with a number of human pathogens, and their possible role as vectors of human disease is discussed.
- Anatomy and Physiology