(') BULLETIN 674, U. B. DEPARTMENT OF AGRICULTUKE. 



In sheep, young animals which have just been weaned pre found to 

 osl susceptible, the disease manifesting itself in an acute form! 

 There is marked depression, high temperature, labored respiration, 

 loss of appetite, muscular trembling, and frequently colicky pains. 

 A subacute and a chronic form of the disease are also recognized, the 

 latter affecting principally older sheep. Aside from the febrile 

 changes, weakness, etc.. there is noted in the subacute form a dis- 

 charge from the eye- and nose which at first is serous, later becoming 

 purulent. There may be also pulmonary impairment (pneumonia), 

 or there may be evidence of enteritis. Occasionally the symptoms 

 subside only to return in a more chronic form, which manifests itself 

 principally as a chronic affection of the lungs, with gradual emacia- 

 tion of the animal. Sometimes the joints are involved, swellii g 'if 

 the knee joints being noted in some cases. 



In swine the disease sometimes manifests itself in a peracute form, 

 the animal showing symptoms of a general septicemic condition. 

 Red spots may be noted on various parts of the body, especially 

 around the ears and on the neck and rump. When affected with 

 this form of the disease the animal usually dies within a few hours 

 after the first manifestations of symptoms. In acute swine plague 

 the disease usually occurs as a necrotic pleuropneumonia. There is 

 labored respiration, dry, spasmodic cough, a slimy discharge from 

 the nose, sometimes a purulent conjunctivitis, cyanotic membranes, 

 constipation followed by diarrhea, the feces sometimes containing 

 blood. The animal becomes greatly emaciated and usually dies in 

 from 1 to 2 weeks. Sometimes the acute form changes into the 

 chronic type, in which case the acute symptoms subside, and the 

 cough and evidence of pulmonary involvement continue for a con- 

 siderable time. Progressive emaciation occurs and a chronic inflam- 

 mation of the joints may develop. The animals die in from '.) to 6 

 weeks from complete exhaustion. Sometimes, however, the lung foci 

 may become encapsulated, and the animals may even be fattened in 

 spite of the condition of the lungs. 



ANATOMICAL CHANGES. 



Swellings will be found in the subcutaneous tissues. If these 

 enlargements are examined they are found to consist of collections 

 of jellylike material tinged with blood. Occasionally they are lim- 

 ited to a single shoulder or flank, when they may be mistaken for 

 blackleg. The lymph glands are enlarged and are injected with 

 blood. The mucous membranes which line the respiratory tract 

 are similarly a fleeted. False membranes composed of fibrinous exu- 

 date may develop in the throat. The spleen remains normal. Hem- 

 orrhages are constant in the connective tissues around the kidneys 

 and within the walls of the intestines. 



