Dourine 89 



The plan of control adopted in the outbreak in Illinois was to 

 make a rigid inspection of every breeding stallion within 

 the infected zone and in the adjoining territory and to keep 

 them under constant observation. In the case of each stall- 

 ion which showed symptoms of the disease or which had 

 -served a diseased mare or a mare which had later become diseased 

 without other known exposure, his breeding record was examined 

 in detail and each mare which had been bred to him was placed 

 Tinder quarantine and subjected to repeated observation. All 

 animals which were found diseased were either destroyed and 

 the owners compensated, or they were placed under a strict quar- 

 antine for life, by the terms of which they were allowed to be 

 worked, but not to be bred, sold or exchanged. 



Under these conditions, almost all the affected mares wgre 

 Tcilled and the few remaining ones were closely watched. The 

 affected stallions were all destroyed. The mares which had been 

 exposed to the disease, but had not become affected, were kept 

 under quarantine for a year or more and subjected to rigid in- 

 spection from time to time and were finally released when it 

 seemed perfectly clear that they were not, and had not been, dis- 

 -eased. The effect of these measures has been highly satisfac- 

 tory and no recurrence of the disease has come to light during 

 the twenty years which have elapsed since the outbreak. At 

 that date the trypanosomum equiperdum was unknown and its 

 presence or absence could not enter into the question of diag- 

 nosis or control, physical symptoms alone being relied upon. 



Upon one occasion, during the early stages of control work, 

 the owner of a stallion, who doubted the diseased condition of 

 his animal, clandestinel}'^ permitted him to serve a mare, which 

 became infected. The destruction of all affected stallions shortly 

 thereafter put a stop to such accidents. 



It is of primary importance in all outbreaks of the disease to 

 provide early for the entire cessation of breeding, or, we might 

 more strictly say, of copulation or attempts at copulation between 

 -animals. In this respect, it is important that colts which are 

 reaching the breeding age should be properly castrated or other- 

 wise made secure. Stallions of breeding age, which have become 

 affected, should be destroyed promptly, or placed under safe 

 quarantine, since they constitute the greatest source of danger. 

 Destruction of the affected animal is highly important, since in 



