378 The Diseases of Animals 



A vaccine against contagious abortion has been pre- 

 pared, and recently placed on the market, that promises 

 to be of great value in dealing with this serious disease. 

 Cows should be kept in fair flesh and in a good, vigorous 

 condition. 



FOOT-AND-MOUTH DISEASE 



Foot-and-mouth disease is a highly infectious dis- 

 order, attacking cattle principally, but easily trans- 

 mitted to sheep, goats, pigs, and other domestic animals. 

 Man frequently contracts the disease from infected 

 animals. It is generally considered to be a germ dis- 

 disease, although the specific organism has not been 

 discovered. This disease has been known for many 

 years in Europe, and immense losses have followed its 

 ravages, some parts of Europe rarely being free from 

 it, and in other parts outbreaks occurring at irregular 

 intervals. One attack of the disease does not confer 

 immunity, as an animal may have it several times. 



Foot-and-mouth disease varies in virulence. In 

 some outbreaks many animals die, but in most cases the 

 mortality is not high, the greatest loss resulting from a 

 falling off in flesh and general deterioration resulting 

 from the disease, and the necessary restriction of the 

 live-stock trade which follows. The disease is trans- 

 mitted by direct contact, and through the medium of 

 infected food, litter, watering places, stables, cars and 

 attendants. It is possible that the contagion may be 

 carried short distances in the air. The milk of an 

 affected animal is highly dangerous. The period of 

 incubation, or the time that elapses between exposure 



