title: Lamsiekte (botulism): solving the aetiology riddle.
abstract: The reason or reasons why it took Sir Arnold Theiler so many years to unravel the riddle of  the aetiology of lamsiekte in cattle and whether P.R. Viljoen's lifelong grudge for receiving  insufficient credit from Theiler for his research contribution was justified are analysed in this  paper. By 1912, Theiler knew that Duncan Hutcheon had advocated the use of bonemeal as  a prophylactic against the disease in the early 1880s. Hutcheon's colleague, J.D. Borthwick,  had shown conclusively in a field experiment in 1895 that lamsiekte did not occur in cattle  fed a liberal allowance of bonemeal; and bone-craving had been identified by Hutcheon and  several farmers as being associated with the occurrence of the disease (a 'premonitory' sign).  Hutcheon regarded a phosphate deficiency of the pastures as the direct cause of lamsiekte.  However, Theiler did not accept this, was convinced that intoxication was involved and  developed a 'grass toxin' theory. Viljoen (1918) also latched onto the grass toxin theory.  He did not believe that osteophagia existed, stating categorically that he had not observed  it on the experimental farm Armoedsvlakte where &gt; 100 cases of lamsiekte had occurred  during the &gt; 3 years that he spent there. Moreover, he did not believe in the prophylactic  value of bonemeal. However, careful analysis of a subsequent publication, of which he was a  co-author, revealed that in late 1918 and early 1919 he reproduced the disease by drenching  cattle with blowfly pupae and larvae as well as with crushed bones from decomposing bovine  carcasses. For this breakthrough he did not get proper credit from Theiler. Reappointed to  study lamsiekte on Armoedsvlakte in the autumn of 1919, Theiler, probably already aware  that the toxin he was seeking was in the decomposing bones or carcass material rather than  the grass, deliberately 'walked with the cattle' on the farm to encounter a classic manifestation  of bone-craving (osteophagia). The penny then immediately dropped. Theiler, actually  rationalising an hypothesis that was about four decades old, did so with a vengeance. Within  less than two years he had reproduced lamsiekte by exposing cattle with natural bone-craving  to rotten carcass material, had chemical proof that the grazing was phosphorus-deficient, had  developed a satisfactory bonemeal prophylactic dosage programme, and the bacterial toxin  concerned - perhaps the trickiest contribution - had been produced in culture. Hence the table  was set for the later development of an excellent lamsiekte vaccine.
authors: rbigalke@telkomsa.net
authors: Rudolph D
authors: RD
authors: Bigalke
mesh_terms: D000818:Animals; D001842:Bone and Bones / Q000382:microbiology; D001906:Botulism / Q000209:etiology / Q000266:history*; D002417:Cattle; D002418:Cattle Diseases / Q000209:etiology / Q000266:history* / Q000517:prevention & control; D003014:Clostridium botulinum / Q000302:isolation & purification; D005247:Feeding Behavior; D049672:History, 19th Century; D049673:History, 20th Century; D007794:Lameness, Animal / Q000209:etiology / Q000266:history* / Q000517:prevention & control; D010758:Phosphorus / Q000172:deficiency*
chemical_list: D010758:Phosphorus