Foot -and -Mouth Disease 377 



and signs of the development of the disease, usually 

 is short, but may vary from twenty -four hours to twenty 

 days. Most cases develop within two or three days 

 after exposure. 



Foot-and-mouth disease usually starts with a chill. 

 The animal remains by itself, the back is arched, hair 

 erect, flanks tucked up, and there is shivering or twitch- 

 ing of the muscles. A sick auinial moves with re- 

 luctance, and there is stiffness or marked lameness in 

 the gait. A thick, yellowish secretion collects at the 

 inner corners of the eyes and about the edges of the 

 nostril. The temperature of the animal rises from two 

 to five degrees Pahr. Blisters form in the mouth, about 

 the feet and on the udder. The blisters vary in size 

 from that of a pea to a quarter of a dollar, and are filled 

 with a watery fluid. They soon burst, leaving raw 

 sores with shreds of tissue hanging about the edges. In 

 the mouth the blisters usually form on the lips, tongue, 

 cheeks and pad of upper jaw. The animal champs the 

 jaws with a smacking noise. There is profuse slavering 

 from the mouth. The saliva at first is normal, but later 

 becomes thick and ropy. The mouth is often so sore 

 that the animal is unable to partake of solid food. The 

 blisters about the feet usually occur between the toes of 

 cattle, or about the coronet, and often cause severe lame- 

 ness. One or all of the feet may be affected. After 

 the blisters burst, raw, angry sores result. In some 

 cases, the hoof may be shed, or the ulceration may in- 

 volve the greater part of the soft structures of the foot. 



So far as known, foot-and-mouth disease w-as first 

 introduced into America in the summer, or early fall, of 



