Iiiflanimatiou of the Parotid Gland. 203 



be directed against the underlying primary condition and no 

 direct treatment of the salivation is required. Diem obtained 

 recovery in a case due to swelling of the parotid gland by re- 

 peated injections of pilocarpine, followed by inunctions with 

 an iodine-iodide of potash ointment. 



2. Inflammation of the Parotid Gland. Parotitis. 



Etiology. Parotitis occurs, as a primary affection, with 

 comparative frequency among domestic animals, after trau- 

 matic injury of the parotid region. It occurs rarely in epi- 

 zootic form as a specific infection among cattle, horses, dogs, 

 cats and goats. The cause of this form of the disease is prob- 

 ably an infective agent gaining entrance into the glandular tis- 

 sue either through the salivary duct or through the general 

 blood circulation. The analogous disease of man known as 

 mumps or parotitis epidemica is beyond doubt due to an infec- 

 tion; according to Korsutschewsky, its cause is a micrococcus. 



Bissauge has repeatedly seen parotitis as an epizootic among cattle 

 in the neighborhood of Orleans in France and always simultaneously 

 with mumps among children. In a dog a case occurred likewise during 

 a mumps epidemic among children, and the affection spread to another 

 dog. A diplococciis was obtained in pure culture from Stenon's duct 

 (Busquet & Boudeaud). The infection of a dog from sick children was 

 demonstrated beyond doubt by Prietsch. 



Aruch saw inflanunation of the parotid and of the submaxillary 

 glands on one side among seventy horses, within one year and a half; as 

 a rule there was suppuration. He repeatedly found lieards of oats and 

 of hordeum sylvaticum in Stenon's duct and in the pus; in one case 100 

 l)eards were in Steuon "s duct. Sometimes the inflammation is caused by 

 bromus maximus (Renault, Meyer) or by vicia tenuifolia (Labat) and 

 it is probable that these plants simply play a role as carriers of patho- 

 genic bacteria. 



Parotitis is frequently secondary in nature, particularly 

 after inflammation of the pharynx. In this case the process 

 probably extends along the connective tissues, but the inflam- 

 mation may also spread from the pharynx along Stenon's duct. 

 Salivary calculi may also cause inflammation in this long duct 

 with secondary involvement of the glandular tissue. 



As a part of the clinical picture in infectious diseases, par- 

 otitis occurs in strangles in the horse, also as a metastatic pro- 

 cess in dog distemper and in influenza of the horse. 



Chronic parotitis develops after repeated traumatic inju- 

 ries (particularly in race horses) in the presence of salivary 

 calculi, and in cattle in connection with actinomycosis. 



Anatomical Changes. Acute parotitis leads to swelling and 

 intense reddening of the glandular tissue and to interstitial 

 serous infiltration of the interlobular connective tissue (paro- 



