title: Factors affecting the toxicity of rotting carcasses containing Clostridium botulinum type E.
abstract: Mice killed shortly after receiving c. 2000 spores of a type E strain of Clostridium botulinum per os were incubated at one of five chosen temperatures together with bottles of cooked meat medium seeded with a similar inoculum. After incubation the rotting carcasses were homogenized. Sterile membrane filtrates of the homogenates (10%, w/v) and pure cultures were then titrated for toxicity. Some of the main findings were confirmed with two further type E strains. Toxicity produced at 37 degrees C was poor in both carcasses and cultures (200-20,000 mouse intraperitoneal LD/g or ml). It was good in both systems at 30 and 23 degrees C, usually reaching 20,000-200,000 LD/g or ml, and in carcasses occasionally more; at 30 degrees C maximal toxicity was reached more quickly in carcasses than in cultures. Prolonged incubation (36-118 days) at 30 or 23 degrees C resulted in complete loss of toxicity in virtually all carcasses but not in cultures. At 16 degrees C the development of toxicity in carcasses was strikingly greater than in cultures. At 9 degrees C neither system produced more than slight toxicity after prolonged incubation. Trypsinization increased the toxicity of cultures but not usually of carcasses. Unfiltered carcass homogenate (10%, w/v) with maximal intraperitoneal toxicity was harmless for mice by mouth in doses of 0.25 ml. These findings differed in important respects from those made earlier with a type C strain.
authors.affiliation: Nuffield Laboratories of Comparative Medicine, Zoological Society of London, Regent's Park.
authors.forename: G R
authors.initials: GR
authors.lastname: Smith
authors.forename: A
authors.initials: A
authors.lastname: Turner
authors.forename: D
authors.initials: D
authors.lastname: Till
mesh_terms: D000818:Animals; D001431:Bacteriological Techniques; D001905:Botulinum Toxins / Q000032:analysis / Q000633:toxicity*; D003014:Clostridium botulinum / Q000254:growth & development* / Q000472:pathogenicity; D051379:Mice; D013696:Temperature
chemical_list: D001905:Botulinum Toxins