36 



The period of the eruption of the last permanent teeth or the 

 end of the period of development from the colt to an adult horse, at 

 which time the animals usually have a tendency to fatten and be ex- 

 cessively full-blooded, also seems to be a predisposing period for the 

 contraction of this as well as of the other infectious diseases. 

 Thoroughbred colts are very susceptible, and frequently contract 

 strangles at a somewhat earlier age than those of more humble origin. 

 Mules and asses are much less susceptible and are but rarely affected. 

 Other animals are not subject to this disease, but there is a certain 

 analogy between it and distemper in doe^. After exposure to infec- 

 tion there is a period of incubation of the disease, lasting from two 

 to four days, during which the animal enjoys its ordinary health. 



Symptoms. The horse at first is a little sluggish if used, or 

 when placed in its stable is somewhat dejected, paying but moderate 

 attention to the various disturbing surroundings. Its appetite is 

 somewhat diminished in many cases, while in some cases the animal 

 eats well throughout. Thirst is increased, but not a great deal of wa- 

 ter is taken at one time. If a bucket of water is placed in the manger 

 the patient will dip its nose into it and swallow a few mouthfuls, 

 allowing some of it to drip back, and then stop, to return to it in a 

 short time. The coat becomes dry and the hairs stand on end. At 

 times the horse will have chills of one or the other leg, the fore quar- 

 ters, or hind quarters, or in severe cases of the whole body, with 

 trembling of the muscles and dry ness of the skin. 



If the eyes and mouth are examined the membranes are found 

 reddened to a bright rosy color. The pulse is quickened and the 

 breathing may be slightly accelerated. At the end of a couple of 

 days a cough is heard and a discharge begins to come from the nos- 

 trils. This discharge is at first watery; it then becomes thicker, 

 somewhat bluish in color, and sticky, and finally it assumes the yel- 

 lowish color of matter and increases greatly in quantity. 



At the outset the colt may sneeze occasionally and a cough is 

 heard. The cough is at first repeated and harsh, but soon becomes 

 softer and moist as the discharge increases. Again the cough varies 

 according to the source of the discharge, for in light cases this may 

 be only a catarrh of the nasal canals, or it may be from the throat, 

 the wind-pipe, or the air tubes of the lungs, or even from the lungs 

 themselves. According to the organ affected the symptoms and 

 character of cough will be similar to those of a bronchitis, or lung 

 fever caused by ordinary cold. 



Shortly after the discharge is seen a swelling takes place under 

 the jaw. This is at first puffy, swollen, somewhat hot and tender, 

 and finally becomes distinctly so, and an abscess is felt, or haying 

 broken itself the discharge is seen dripping from a small opening. 

 When the discharge from the nostrils has fully developed the fever 

 usually disappears and the animal regains its appetite, unless the 

 swelling is^ sufficient to interfere with the function of the throat, 

 causing pain on any attempt to swallow. At the end of four or six 

 days the discharge lessens, the soreness around the throat diminishes, 

 the horse regains its appetite, and in two weeks has regained its usual 



