Michael T. Walsh1; Lee Ann Thomas2; J. Glenn
Songer3; Terry W. Campbel1; Linda Schroeder Tucker2
Diseases associated with clostridia have been well documented in a
number of species. The most common clostridial species cultured from the intestinal tract of
ill and healthy cetaceans is Clostridium perfringens. In an effort to determine a possible
correlation of the organisms presence with disease symptoms, all cultures identified as C.
perfringens were submitted to the National Veterinary Services Laboratories Bacterial
Identification Section for toxin typing. Clostridium perfringens was recovered from the
intestinal tract of Orcinus orca, Pseudorca crassidens, Tursiops truncatus and Kogia simus.
Of nineteen cultures, ten isolates could not be typed due to insufficient toxin production
or no toxin production. Six C. perfringens isolates were shown to be type A by use of a
mouse protection assay in which 0.5ml of filtrate was inoculated into each of two mice via
the tail vein.
Ten strains were then forwarded to the University of Arizona, Department
of Veterinary Science for typing by polymerase chain reaction assay. Of these, all but one
of the strains was determined to be genotype A positive for the alpha toxin, negative for
beta and epsilon toxin. All were negative for the enterotoxin gene. It could not be
determined if any were type E since there is currently no test available. Five additional
samples are currently being evaluated at this time.
Clinically these organisms may be responsible for enterocolitis in
debilitated animals or individuals on prolonged antibiotic therapy. Treatment may include
suitable antibiotics which are not absorbed from the intestinal tract.