580 SPORADIC DISEASES. 



suffering from pleurisy, pleurodynia, and otlier diseases. Some 

 horses habitually grunt when struck at or moved suddenly. A 

 great number of cart-horses are so affected, and big horses of 

 all breeds are very apt to be grunters, whilst they may be quite 

 sound in tlieir wind. Horses with heavy jaws and ill-set necks 

 often emit this sound ; and again any horse may do it if it has 

 been fed for a time with bulky food. The sound is always to 

 be regarded with suspicion, and the animal further tried for its 

 wind, as it generally accompanies roaring or whistling. If the 

 grunter, however, stands the tests used to detect roaring, without 

 making any noise in its breathing, it may be considered buuiid 

 Grunting is often symptomatic of occult glanders. 



2. Whistling. — This sound is of two kinds, a soft or moist 

 and a dry or hard whistle. 



Soft whistling is due to acute laryngitis, when a considerable 

 increase of mucus has taken place, and when the mucous 

 membrane is temporarily swollen. When due to the presence 

 of mucus it partakes more of a wheezing sound, and is generally 

 diminished when the animal coughs. The sound arising from 

 tumefaction of the laryngeal mucous membrane is greater during 

 the inspiratory than the expiratory act. It is very similar in 

 character to the dry sound to be described ; but in addition to 

 the sound, symptoms of catarrh, fever, or acute irritation of the 

 larynx are present. This sound indicates a temporary unsound- 

 ness, and in many instances it is unsafe to pronounce a decided 

 opinion for several days or even weeks after the subsidence of 

 other symptoms. In such instances the mucous membrane has 

 undergone some degree of thickening ; there is relaxation of the 

 vocal cords, a want of tone in the larynx generally, that require 

 some time to overcome. It is impossible to pass an animal of 

 this kind as perfect, and it would be unwise to give a decided 

 opinion until all abnormal sound has disappeared. 



Dry whistling. — This sound has been generally looked upon 

 as a modilication of roaring. I am, however, of opinion that 

 whistling and roaring are due to different pathological conditions 

 of the larynx, and that they may exist independently of each 

 other ; that roaring does not always terminate in whistling, nor 

 whistling in roaring. 



Whistling, like roaring, is a sound emitted more particularly 

 during inspiration, and is due to a diminution of the calibre of 

 the larynx, or sometimes trachea, owing to a permanent thicken- 



