A CYTOTOXICITY ASSAY FOR CLOSTRIDIUM SPIROFORME ENTEROTOXIN IN CECAL FLUID OF RABBITS

Clostridium spiroforme enterotoxin-mediated diarrhea can be a common c ause of mortality among weanling age rabbits. Definitive diagnosis of this disorder requires detection of the causative enterotoxin. Using f iltered cecal supernatant from necropsy specimens, antibodies to C. sp iroforme and its products and Vero cells, a cytotoxicity assay was per formed on 22 rabbits with clinical signs and lesions consistent with C . spiroforme enterotoxin-mediated diarrhea. A cytotoxic effect was det ected, generally within 4 h, in 18 of 22 rabbits. The cytotoxic effect was blocked by preincubation of the cecal material with antibodies to C. spiroforme and its products. Culture of cecal contents and smears of cecal contents identified C. spiroforme in 10/22 and 12/22 cases, r espectively. This cytotoxicity assay provided a rapid and sensitive me thod for diagnosing C. spiroforme enterotoxin-mediated diarrhea.