South African Horse Sickness, etc. 561 



the experiment a step farther and inoculated his artificially im- 

 munized sheep with 2^ cc. of a virulent serum-gelatine-agar 

 culture. It was rather unwell for half a day and walked lame 

 but soon recovered. A dose of -^ cc. of the same culture killed 

 in fifteen hours a larger sheep that had not been artificially im- 

 munized. 



Treatment. Though some cases of braxy recover yet the treat- 

 ment of the disease can hardly be seriously considered as yet. 

 A disorder which is so rapid in its progress, so early associated 

 with such great and rapidly extending lesions of the most vital 

 organs, and which proves fatal so early and almost invariably, 

 leaves little room for successful treatment. In the milder cases, 

 likely to recover of their own accord, this may be hastened by 

 the internal use of antiseptics and purgatives, and perhaps even 

 by antitoxic serum from the blood of an immunized animal. 



SOUTH AFRICAN HORSE SICKNESS. CgDEMA MY- 

 COSIS. DUNPAARDZIEKTE. DIKKOPZIEKTE. 



Definition: Geographical distribution : S.Africa; enzootic or epizootic on 

 damp soils ; damp, humid atmosphere. Pathogenesis : horses, and more mildly 

 mules and asses, quagga ; (cattle and goats ?). Causes : green forage, from 

 rich, damp lands, eaten dewy ; cut and fed with dew on ; dried in sun safe ; 

 so of horses stabled or coralled ; in hot summer only ; inoculable ; peni- 

 cillium ; cultures cause the disease ; debility. Forms : lung sickness — 

 bead sickness— blue tongue. Symptoms : incubation 8 days. Fulminant 

 form asphyxiates in an hour. Acute lung form has rigor ; remittent hyper- 

 thermia ; prostration ; dyspncea ; cyanosis ; serous nasal discharge ; froth- 

 ing ; gurgling breathing ; cough ; death in three orfonrdays. Head oedema ; 

 general swelling and oozing of serum. Blue tongue : great lingual swelling ; 

 cyanosis ; coldness ; projection from mouth : salivation ; stertor ; asphyxia. 

 Three forms combined. Mortality. Lesions : serous exudate coagulates 

 with heat or blood ; intermuscular exudates ; wliole head densely infiltjrated ; 

 excessive bloody pleural effusion ; punctiform petechise ; lungs pale, yellow, 

 great interlobular infiltration ; or, if worked, hepatization ; dark, congested 

 mucosse ; blood diffluent ; heart pale ; spleen enlarged, blood-gorged ; kid- 

 neys infiltrated ; gastro-intestinal congestions ; cerebro-spinal effusion. 

 Prevention : keep indoors during summer and autumn ; allow no fresh 

 damp forage ; or cut only after dew is off ; check rein or muzzle ; pastured 

 horses must be stabled at night or in damp weather. Immunization : by 

 protective inoculations ; recovered horse is re- inoculated until a high grade 

 of resistance is secured and his blood used to immunize. 

 36 



