Clostridium perfringenstoxin types from wild-caught Atlantic cod (Gadus morhuaL.), determined by PCR and ELISA

Abstract

Ninety-five fecal samples from Atlantic cod (Gadus morhua L.), caught along the northern Norwegian coast, were examined bacteriologically for occurrence of C. perfringens. Isolates were examined by polymerase chain reaction (PCR) for genes encoding the four lethal toxins (α, β, ε, and ι) for classification into toxin types and for genes encoding enterotoxin and the novel β2 toxin for further subclassification. In addition, a commercial enzyme-linked immunosorbent assay (ELISA) kit for detection of C. perfringens α, β, and ε toxin was used. Clostridium perfringens could be isolated in 37 fecal samples (38.9%) from cod. All isolates were C. perfringens toxin type A (α toxin positive) as determined by PCR and also ELISA. In addition, in isolates from two cod (2.1%) the gene encoding for β2 toxin was found (A, β2) by PCR. Genes encoding for β, ε, and ι toxins and enterotoxin were not found. This is the first detection of C. perfringens alpha and β2 toxin in cod and of β2 toxin in fish in general. The origin of this bacterium in cod is discussed.Key words: Clostridium perfringens, cod, Gadus morhua L.