562 DISEASES OF THE HORSE. 



symptom to be noticed is a loss of vitality combined with an irregular 

 appetite or other digestive disturbance, and with a tendency to stum- 

 ble while in action. These earlier symptoms, however, may pass unob- 

 served, and the appearance of an intermittent or migratory lameness 

 without any visible cause may be the first sign to attract attention. 

 This shifting and indefinite lameness, involving first one leg and then 

 the other, is very suggestive, and is even more important when it is 

 associated with a tendency to lie down frequently in the stall and the 

 absence of a desire to get up, or the presence of evident pain and 

 difficulty in arising. 



About this time, or probably before, swelling of the bones of the 

 face and jaw, which is almost constantly present in this disease, will 

 be observed. The bones of the lower jaw are the most frequently 

 involved, and this condition is readily detected with the fingers by the 

 bulging ridge of the bone outside and along the lower edge of the 

 molar teeth. A thickening of the lower jawbone may likewise be 

 identified by feeling on both sides of each branch at the same time 

 and comparing it with the thinness of this bone in a normal horse. 

 As a result mastication becomes difficult or impossible and the teeth 

 become loose and painful. The imperfect chewing which follows 

 causes balls of food to form which drop out of the mouth into the 

 manger. Similar enlargements of the bones of the upper jaw may be 

 seen, causing a widening of the face and a bulging of the bones about 

 midway between the eyes and the nostrils. In some cases the nasal 

 bones also become swollen and deformed, which, together with the 

 bulging of the bones under the eyes, gives a good illustration of the 

 reason for the application of the term bighead. 



Other bones of the body will undergo similar changes, but these 

 alterations are not so readily noted except by the symptoms they occa- 

 sion. The alterations of the bones of the spinal column and the 

 limbs, while difficult of observation, are nevertheless indicated by the 

 reluctance of the animal to get up and the desire to remain lying for 

 long periods of time. The animal easily tires, moves less rapidly, 

 and if urged to go faster may sustain a fracture or have a ligament 

 torn from its bony attachments, especially in the lower bones of the 

 leg. An affected horse weighing 1,000 pounds was seen by the writer 

 to fracture the large pastern bone from rearing during halter exercise. 



The animal becomes poor in flesh, the coat is rough and lusterless, 

 and the skin tight and harsh, producing a condition termed " hide- 

 bound," with considerable " tucking up " of the abdomen. The 

 horse shows a short, stilted, choppy gait, which later becomes stiffer 

 and more restricted, while on standing a position simulating that in 

 founder is assumed, with a noticeable drop to the croup. The animal 

 at this stage usually lies down and remains recumbent for several 



