609 



the bearers of the germs or this or some otner infectious disease, and 

 at last it succumbs. 



The period of the erui)tiou 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 excessively 

 full-blooded, also seems to be a predisposing- jDcriod for the contraction 

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

 colts are very susceptible, and frequently contract strangles at a some- 

 what earlier age than those of more humble origin. Mules and asses 

 are much less suscei^tible and are but rarely affected. Other* animals 

 are not subject to this disease, but there is a certain analogy between 

 it and distemper in dogs. After exj)osure to infection 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 atten- 

 tion to the various disturbing surroundings. Its appetite is somewhat 

 diminished in many cases, Avhile in some cases the animal eats well 

 throughout. Thirst is increased, but not a great deal of water is 

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

 before the patient, it 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 quarters or hind quarters, or in severe cases of the whole body, 

 with trembling of the muscles, dryness of the skin, and its hairs stand- 

 ing on end. 



If the eyes and mouth are examined the membranes are found red- 

 dened to a bright rosy color. The pulse is quickened and the breath- 

 ing may be slightly accelerated. At the end of a couple of days a 

 cough is heard and a discharge begins to come from the nostrils. 

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

 bluish in color, and sticky, and finally it assumes the yellowish 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 afi'ected the symptoms and character of cough 

 will be similar to those of a laryngitis, bronchitis, or lung fever caused 

 by ordinary cold. 



Shortly after the discharge is seen a swelling takes i)lace under the 

 jaw, or in the intermaxillary space. This is at first puffy, swollen, 

 somewhat hot and tender, and finally becomes distinctly so, and an 



