456 FOOT AND MOUTH DISEASE 



§ 362. Symptoms. The symptoms of foot and mouth 

 disease vary greatly in different epizootics, sometimes they are 

 quite mild and at others very severe. The first evidence of 

 the disease is a rise of temperature which in cattle rarely 

 exceeds 104° F. The mucous membrane of the mouth becomes 

 reddened, the appetite is diminished, and rumination ceases. 

 The mouth is usually kept closed and the quantity of saliva is 

 increased. A smacking sound is not infrequently made by the 

 animal. These symptoms are chiefly due to the pain accom- 

 panying the disease in the mouth. After two or three days 

 the eruption appears. This consists of small yellowish-white 

 vesicles or blisters, varying in size from a hemp seed to a pea, 

 on the gums and inner surface of the lips, the inside of the 

 cheeks, the border and the under surface of the tongue. They 

 may become half an inch or more in diameter. In some cases 

 the back of the tongue may be the seat of large blisters. 



These vesicles burst soon after their appearance, some- 

 times on the first day. More rarely they may persist for two 

 or three days. After they have ruptured the grayish-white 

 membrane forming the blister may remain for a day or more 

 or disappear speedily and leave deeply reddened areas or ero- 

 sions which are very painful. These exposed areas may soon 

 become covered again with the normal epithelium or they may 

 be converted into ulcers. In this stage the saliva forms in 

 large quantities and hangs in strings, from the mouth. In 

 eight to fourteen days the disease may have entirely disap- 

 peared. 



In addition to the changes in the mouth, one or more feet 

 may become diseased. The skin around the coronet and in 

 the cleft between the toes becomes hot and tender and may 

 swell. Blisters appear as in the mouth, but they are speedily 

 ruptured and the inflamed, exposed areas are covered with a 

 viscid exudate. 



The udder, more particularly the teats, may be the seat of 

 lesions. Some authorities regard the udder disease merely as 

 the result of infection during milking. The vesicles are 

 broken by the hands of the milker and the teats become cover- 



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