514 DISEASES OF THE HOESE, 



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

 to four days, during which the animal enjoys its ordinar}^ 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, while 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 the 

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

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

 time. The coat Ijecomes 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 and dryness of the skin. 



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 dis- 

 charge 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 affected the symptoms and character of cough 

 will be similar to those of a lar\Tigitis, bronchitis, or lung fever 

 caused by ordinary cold. 



Shortly after the discharge is seen a swelling takes place under the 

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

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

 abscess is felt, or having broken itself the discharge is seen dripping 

 from a small opening. AYhen 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 func- 

 tion 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 condition. Old and strong horses may have the 

 disease in so light a form that the fever is not noticeable ; they may 

 continue to eat and perform their ordinary work as usual and no 

 symptom may be seen beyond a slight discharge from the nose and a 

 rare cough, which is not sufficient to worry anj' but the most particu- 



