Abstract:
On reviewing the results of these experiments, there can be little doubt that the plant Cotyledon wallichii Harv. (kandelaar bos or bandjes bos) is at least one of the causes of the disease known as krimpsiekte in the western Karroo. The possibility of the parasitic nature of the disease can be completely ruled out for the following reasons: (1) Neither by inoculation nor by contact was it possible to transmit the disease. (2) In no instance on post-mortem was a parasitic organism found which might suggest a parasitic nature of the condition. (3) By sterilizing the plant, both by boiling and by autoclaving, the virulence of the plant was not appreciably reduced, as would be expected in the case of a parasitic organism. (4) Very large quantities of the meat of krimpsiekte animals were required to be fed to dogs in order to produce symptoms, since the toxin had apparently been considerably diluted as a result of its distribution through the tissues. If the disease were of a parasitic nature, considerably smaller doses would be expected to reproduce the malady. (5) Furthermore, since the toxin of this plant is apparently thermostabile, the meat and organs of a krimpsiekte animal cannot be considered safe for human consumption even after boiling or cooking. This conclusion, it will be observe, is contrary to popular belief.
