40 Catarrh of the Larynx. 



upon the mucosa for a longer time or repeatedly. Consequently 

 chronic laryngitis is observed particularly among such animals 

 as are kept permanently under unfavorable conditions, es- 

 pecially in impure air. In old dogs one frequently sees an 

 obstinate chronic laryngitis. 



Other causes are: disturbances of circulation in chronic 

 heart disease, chronic inflammatory diseases of the deeper 

 respiratory passages and of the neighboring organs, new forma- 

 tions (cysts, fibroma, sarcoma, carcinoma, or other tumor-like 

 swellings — polyps, actinomycosis, tuberculosis, glanders), par- 

 ticularly those which have a tendency to ulcerate. 



Susceptibility. Idiopathic laryngitis is seen particularly 

 in pet animals with little power of resistance, for instance in 

 horses kept in warm stables and in house dogs. 



Anatomical Changes. In acute laryngitis the epiglottis, 

 the arythenoid cartilages and the vocal cords are intensely 

 reddened and swollen; in a later stage they are abundantly 

 covered with mucus and sometimes infiltrated with blood. In 

 severe cases there occur round superficial ulcers (Bruckmiiller). 



In chronic catarrh the swollen parts are more grayish in 

 color; in consequence of the swelling of the mucous glands 

 the surface is finely granular (laryngitis granulosa) or the 

 epithelia which have proliferated here and there may form 

 small nodules. The mucosa is thick and may in obstinate cases 

 be set with villous excrescences; in horses the mucous glands 

 may occasionally be changed into small cysts. 



Symptoms. The principal and most common symptom of 

 acute laryngitis is cough; it is at first short, dry and rough, 

 later drawn and moist, always, however, more or less painful. 

 In the presence of great tenderness it may be weaker. The 

 animals are at short intervals subject to a tormenting cough, 

 sometimes in the form of convulsive attacks. They stretch 

 their necks forward and backward. Horses often paw and 

 exhibit an anxious look. Dogs sometimes vomit after coughing. 

 These attacks generally come on after the action of an external 

 irritant on the larynx, especially after the animal has been 

 led out of the barn, after a draft of cold air through the barn 

 door, after the ingestion of cold water, or of dusty or hot 

 feed, or after sudden or prolonged exercise, while animals 

 standing or lying at rest only cough occasionally. The patients 

 sometimes expel a tenacious mucus through the mouth or nose ; 

 such mucus, however, more usually adheres to the pharyngeal 

 wall and is subsequently swallowed. 



The increased sensibility of the laryngeal mucosa may 

 be demonstrated objectively by pressure upon the arythenoid 

 or thyroid cartilages ; even mild pressure will likely pro- 

 duce repeated coughing and the animal will attempt to get 



