The production of Clostridium botulinum type A, B and D toxin in rotting carcasses

Carrion is a major source of botulinal toxin for animals. A type D strain of Clostridium botulinum differed from type A and B strains in producing (1) much higher concentrations of toxin in putrefying mouse carcasses at several different temperatures over a period of 35 days, (2) toxicity that sometimes persisted in mouse carcasses for at least a year, and (3) mouse carcasses with exceptionally high oral toxicity. Fish carcasses were much less favourable than mouse carcasses for type D toxigenesis. The study, together with earlier studies on types C and E, indicated that carrion contaminated with C. botulinum type C or D is likely to be particularly dangerous for animals that may ingest it. This accords with the observation that carrion-transmitted botulism in animals is usually caused by type C or D.