Catarrhal Laryngitis in the Horse. 121 



products, or even parasitisms may thus "operate. Closely allied 

 to these are chills, cold rains or snows, prolonged exposure with- 

 out exercise or clothing, or after clipping, or after perspiration 

 and fatigue ; or swimming or wading cold waters. High feed- 

 ing, hot, close stables, in contrast with the sudden chill when 

 taken out doors, and extension from rhinitis, pharyngitis, 

 staphylitis, guttural pouch inflammation, bronchitis, pneumonia, 

 and even from the infectious strangles, influenza, contagious 

 pneumonia, and glanders must be recognized. 



As direct and special causes may be named : Severe pinching 

 of the larynx to cause coughing ; spasmodic inhalation of food 

 materials that lodge in the larynx ; introduction of a probang . 

 into the larynx, in unskillful attempts to pass it by the mouth ; 

 and the inhalation of irritating and infecting dust. The larynx 

 is, however, much less exposed to infection than the nasal pas- 

 sages as irritants and microbes are liable to be arrested by stick- 

 ing to the moist Schneiderian membrane and thus fail to reach 

 the larynx. In forcible administration of volatile, irritant 

 liquids (ammonia solutions, oil of turpentine, carbolic acid, 

 chloroform, ether, etc. ) , the larynx is very liable to suffer. In 

 the same way operate irritant gases (dry air of stoves, empyreu- 

 matic gases, chlorine, bromine, sulphur fumes, etc.). Krebs 

 mentions a case of laryngitis from contact with infecting pus 

 discharged through the Eustachian tube from a ruptured abscess 

 in the middle ear. Finally the bites of parasites (leeches, 

 oestrus larva, linguatula) may start inflammation in the irritated 

 mucosa. Fractures of the laryngeal cartilages by violence, 

 punctures, and even surgical operations implicating the larynx 

 may be incriminated. 



Symptoms of acute form. All acquainted with horses can 

 recognize the general symptoms of sore throat. The nose is 

 elevated and protruded to avoid compression of the larynx ; it is 

 carried stiffly for the same reason. There is some swelling around 

 the throat or beneath the root of the ears. If the cartilages of 

 the larynx are compressed between the finger and thumb, or if 

 pressure is made in the median line below upon the connecting 

 crico-thyroid membrane the patient instantly coughs and throws 

 up the head to avoid a repetition of the suffering. This tender- 

 ness of the larynx to touch is peculiar to laryngitis and serves to 



