Abstract
During the past year the laboratory has received several specimens of botulinus-like organisms through the courtesy of Drs. P. J. du Toit and E. M. Robinson, Onderste-Poort, Pretoria, South Africa. Although these cultures differ in many ways from those isolated in this country, one strain secured from lamziekte carrion deserves special consideration.
The fluid portion of the original culture was toxic for mice. The antitoxic sera Type A, B and C failed to protect the animals against this poison irrespective of the fact that the symptoms and lesions were in every respect typical for botulism. A highly potent toxin was obtained in beef heart-peptic digest mash (1 cc. = 20,000 guinea pig M.L.D.) and Hibler's brain medium. Protection experiments with the known type antitoxins and a serum supplied by Dr. E. M. Robinson known as “Cl. parabotulinum bovis antiserum” were made on guinea pigs.
The results clearly indicate that the toxin of one of the South African strains of Cl. Botulinum is different from either Cl. Botulinum Type B and C or Cl. Parabotulinum Type A and B.
In pure culture the organism resembles the anaerobe described by Theiler and Robinson. 1 It is a long, slender, Gram-positive, unusually pleomorphic rod which is actively motile under strictly anaerobic conditions. In egg-medium (Rettger) numerous subterminal closteridium-like spores are formed, while in beef heart and other media spores are rarely observed. Rhizoid, non-hemolytic surface colonies appear on properly prepared glucose blood plates. Growth is good and a small amount of gas is formed in beef heart, egg and milk media provided a vaseline seal is used. The protedytic properties are low (Sörensen's figures 1st day 0.5, 14th day 4.0), about the same as the non-ovolytic Type B and slightly higher than the Type C strains.
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