56 HORSE, SWINE AND POULTRY DISEASES 



which have been impregnated by the saliva and soiled by the dis- 

 charge of sick animals. Transmission occurs by direct contact of 

 the discharges of a glandered animal with the tissues of a sound one, 

 either on the exterior, when swallowed mixed with food into the di- 

 gestive tract, or when dried and inhaled as dust. 



The stable attendants serve as one of the most common carriers 

 of the virus. Dried or fresh discharges are collected from the in- 

 fected animal in cleaning, Harnessing, feeding, and by means of the 

 hands, clothing, the teeth of the currycomb, the sponge, the bridle, 

 and the halter, and are thus carried to other animals. An animal 

 affected with chronic glanders in a latent form is moved from one 

 part of the stable to another, or works hitched with one horse and 

 then with another, and may be an active agent in the spreading of 

 the disease without the cause being recognized. 



Glanders is found frequently in the most insidious forms, and 

 we recognize that it can exist without being apparent ; that is, it may 

 affect a horse for a long period without showing any symptoms that 

 will allow even the most experienced veterinarian to make a diagno- 

 sis. An old gray mare belonging to a tavern keeper was reserved for 

 family use with good care and light work for a period of eight years, 

 during which time other horses in the tavern stable were from time 

 to time affected with glanders without an apparent cause. The mare, 

 whose only trouble was an apparent attack of heaves, was sold to a 

 huckster who placed her at hard work. Want of feed and overwork 

 and exposure rapidly developed a case of acute glanders, from which 

 the animal died, and at the autopsy were found the lesions of an 

 acute pneumonia of glanders grafted on chronic lesions, consisting 

 of old nodules which had undoubtedly existed for years. 



Public watering troughs and the feed boxes of boarding stables 

 and tavern stables of market towns are among the most common 

 recipients for the virus of glanders, which is most dangerous in its 

 fresh state, but cases have been known to be caused by feeding ani- 

 mals in the box or stall in which glandered animals have stood sev- 

 eral months before. While the discharge from a case of chronic 

 glanders is much less apt to contain many active bacilli than that 

 from a case of acute glanders, the former, if it infects an animal, 

 will produce the same disease as the latter. It may assume from 

 the outset an acute or chronic form, according to the susceptibility 

 of the animal infected, and this does not depend upon the character 

 of the disease from which the virus was derived. 



There is found a much greater receptivity to contract glanders, 

 in the ass and mule than is found in the horse. In the ass and mule 

 in almost all cases the period of incubation is short and the disease 

 develops in an acute form. It is found that the kind of horse in- 

 fected has an influence on the character of the disease; in full- 

 blooded fat horses of a sanguinary temperament, the disease usually 

 develops in an acute form, while in the lymphatic, cold-blooded, 

 more common race of horses the disease usually assumes a chronic 

 form. If the disease develops first in the chronic form in a horse 

 in fair condition, starvation and overwork are apt to bring on an 



