183 SIR ARNOLD THEILER 



on the veld from Avhicli the grass had been obtained died 

 from Lamziekte. This experiment effectively disposed of 

 the poisonous plant theory. 



Another theory as to the canse of Lamziekte was based 

 on the one brought forward by Prof. Funk. According 

 to him Lamziekte must be considered as an ^^ avitamino- 

 sis '•, which means a disease occasioned by the lack of 

 certain essential components (Vitamines) in the food. 

 The best known case of avitaminosis is the so called Beri- 

 beri, which in eastern countries makes its appearance as a 

 result of the consumption of polished rice Beri-beri 

 ma}^ be brought about artificially in pigeons by feeding 

 them on substances containing no vitamines, but in 

 cattle it proved to be impossible to produce the disease 

 in this way. Accordingly Lamziekte cannot be considered 

 as an avitmnUiosis. 



Yet another theory was that of Professor Hedinger 

 whose opinion w^as that Lamziekte was an infection of the 

 muscular system with parasites (Sarcosporidia). These 

 parasites were detected in the flesh of animals that had 

 suffered from Lamziekte; but later Prof. Viljoen proved 

 that sarcosporidia were to be found in the flesh of almost 

 all healthy animals as well. In one case he counted as 

 many as 800 parasites to each square inch in the flesh 

 of an emaciated animal which had never suffered from 

 lamziekte. 



It is obvious therefore that none of the theories ex- 

 pounded so far could explain the cause of Lamziekte ; and 

 investigators had to turn their attention back again to 

 the veld. The first point for consideration was the possi- 

 bility that tlie disease might be connected with insects. 

 Among the insects which were susi)ected were the pupae 

 of blow flies which are often to be found in the vicinity 

 of carcasses lying on the veld. Pupae were then given 

 to an animal and the first case of Lamziekte was obtained 

 by ingestion, and there could be no doubt that the pupae 

 contained a toxin that produced typical Lamziekte. It 



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