IG 2 DISEASES OF THE DOMESTIC ANIMALS 



guinea pig; with difficulty to sheep and goats; and not at all to 

 cattle. Man is likewise susceptible. The disease is produced by a 

 specific bacillus present in the discharge from the nasal and glandu- 

 lar erosions. These enter the body externally or through the res- 

 piratory tract in dust or in food. The disease is of variable course 

 and usually fatal. The discharge is most virulent in acute cases. 

 In chronic glanders or farcy the discharge may or may not be in- 

 fectious. 



Mode of infection. — An acute case near a sound animal in the 

 barn or at work; contaminated feed, feed boxes, water, dust, har- 

 ness, employees, and utensils. The unsuspected latent case may 

 convey infection or may at any time become acute and virulent. The 

 ass and mule are more susceptible to glanders, while chronic farcy 

 is rarely seen in them. The chronic form of glanders becomes acute 

 through debilitating influences. External infection is apt to be- 

 come an acute form ; that through food produces a chronic type. 



Symptoms. — The local lesion begins by a proliferation of con- 

 nective tissue (nodules) until the circulation is impeded, and break- 

 ing down and erosion occurs. The size of the lesion often depends 

 on local irritation of harness, rain, mud, etc. In speeded horses the 

 lungs are apt to become affected. 



i. Chronic Glanders. — When the disease becomes clinically 

 evident it is far advanced, and there are many cases which show 

 no visible signs of the disease, while in others only one or more 

 signs are present. Typical cases include nasal involvement, in 

 which nodules (from the size of a shot to a pea) on the alse, 

 septum or turbinates, break down in ragged ulcers, having a 

 punched out appearance and a dirty base. The nasal discharge is 

 peculiar, of a gluey or starchy nature and more or less bloody and 

 escapes from one nostril. According to the stage, are seen on the 

 mucous membrane of the septum or about the ake, the ulcers with 

 thickened borders and yellow bases ; or stellate, radiate, or elongated 

 cicatrices. The lungs are often involved, when cough and irregular 



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