SYMPTOMS 341 



organs. He reports having reproduced the disease in dogs 

 with pure cultures of this organism. The writer has not been 

 able to find this bacillus in a few cases which he has examined, 

 but a streptococcus has often appeared in pure cultures from 

 the various organs. There is much need for further investi- 

 gation into the etiology of this malady. That it is produced 

 by a specific cause is very clearly indicated by the reported 

 results of investigations to the effect that dogs inoculated with 

 the nasal discharge of affected animals develop the disease. 



§ 262. Symptoms. The symptoms appear after a period 

 of incubation of from four to six, possibly eight days. They 

 vary to such a degree that it is impossible to refer to all of the 

 manifestations. In some cases the symptoms suggest a general 

 disorder. In others they are referable to certain parts or 

 organs such as the mucosa of the digestive and respiratory 

 tracts, the brain or integument. As a rule several organs are 

 implicated. 



The initial symptoms such as depression, roughened con- 

 dition of the coat, loss of appetite and elevation of temperature 

 are usually suggestive of a general disturbance. 



In a large majority of cases, conjunctivitis is the primary 

 ocular symptom. Tears flow from the eyes and photophobia 

 is present. The mucous membrane of the eyelids becomes 

 highly congested and swollen and the eyelids turgid. The 

 discharge from the eyes which is at first serous soon becomes 

 mucous and purulent. The exuded matter consists of pasty 

 mucous or dirty yellowish pus. This exudate collects under 

 the lower eyelids, chiefly at the inner canthus of the eye and 

 soils the edges of the eye lids, upon which it frequently dries 

 into crusts and causes the lids to adhere, especially during the 

 night. Ulcers form on the cornea in consequence of the action 

 of the accumulated and decomposing pus and the patient wiping 

 and rtibbing the eyes with its paws. The epithelium of the 

 cornea sometimes suffers more or less from shallow flat lesions 

 which give the surface of a cornea a rough and uneven appear- 

 ance. Frequently smaller and deeper ulcers form especially 

 toward the center of the cornea. 



In other cases, there is a diffuse, parenchymatous keratitis 



