Toxin production by Clostridium botulinum in grass

S Notermans, S Kozaki, M van Schothorst
1979 Applied and Environmental Microbiology  
Investigations on farms where botulism has occurred in cows showed that proteolytic Clostridium botulinum type B was present in newly made grass silages. Experiments were undertaken to study growth and toxin production of C. botulinum in grass. Of the strains tested only proteolytic strains of C. botulinum types A and B were able to produce toxin with grass as a substrate. Proteolytic strains of type B produced both medium (12S) and large (16S) toxin forms. The minimal water activity (a") for
more » ... activity (a") for toxin production at pH 6.5 and 5.8 was 0.94. At pH 5.3, toxin was produced at an a" of 0.985. These results indicate that proteolytic strains of C. botulinum (if present) may multiply and produce toxin in wilted grass silages. scribed by Northolt et al. (13). The accuracy of measurement was ±0.005. Detection of C. botulinum in silages. Samples 767 on May 4, 2020 by guest http://aem.asm.org/ Downloaded from
doi:10.1128/aem.38.5.767-771.1979 fatcat:5cbdkjd2gndb5npirqm4hif7oa