FOOT-AND-MOUTH DISEASE. 419 



tough, fibrous nature of the bovine skin, it is exceed- 

 ingly rare for sloughing to occur upon any part of the 

 body other than those mentioned. 



The attack upon the feet of an animal is frequently 

 manifested in all four feet at once, but one or more of 

 the feet may entirely escape and remain unaffected 

 throughout the course of the disease. The ulceration of 

 the interdigital tissue may extend to the ligaments of 

 the fetlock or produce disease of the joint or bone. As 

 the feet become sensitive and sore the animal lies down 

 persistently, and it has been found that bed sores de- 

 velop with amazing rapidity in all such cases and wholely 

 baffle all attempts at treatment until after the patient 

 has regained its feet. 



The disease may attack some of the internal organs 

 before it appears upon any of the external tissues. 

 These cases are very liable to prove quickly fatal. The 

 animal dies from paralysis of the heart, due to the 

 formation of poisonous principles within the system, or 

 it may suffocate by reason of the action of these same 

 poisons upon the tissues of the lungs, or it may choke 

 to death as a result of paralysis of the throat. 



In cases of serious affection of the udder the erosions 

 will often be found located vdthin the passages of the 

 teats, resulting in a " caked ' ' udder, and the same toxic 

 poisoning which is the cause of death in the apoplecti- 

 form types just mentioned may arise from this source. 

 In any event the milk from such cases will be found 

 dangerous for use, causing fatal diarrhea in sucking 

 calves or young pigs and serious illness in human con- 

 sumers. The milk obtained from cows suffering with 

 foot-and-mouth disease is not readily converted into 

 either butter or cheese, but remains thick, slimy, and 

 inert in spite of churning and attempts at curdling. 



