DISEASES CAUSED BY INFECTED MILK 181 



appetite; at the same time there is lameness, emaciation, | 

 and diminution in the quantity of milk secreted. 



The disease is remarkable in that the mortality is very I 

 light (only about one per cent of the animals affected die). 

 The economic losses, however, are very great, for an ani- 

 mal, after passing through an attack of foot-and-mouth 

 disease, may be practically worthless as a milch cow and 

 will only bring a very greatly reduced price at the slaugh- 

 ter-house. 



The milk becomes thin, bluish, and poor in fat. In the 

 early stages or in a mild attack of the disease, the milk may 

 present only a few abnormal characteristics, such as a fall 

 in specific gravity to 1.023 or 1.025 and a reduction in the 

 quantity of milk sugar and casein. When the disease is 

 fully developed, about the third day, the milk invariably 

 contains inflammatory products of very pronounced char- 

 acter and the quantity of milk secreted is greatly reduced. 

 Cows affected with the malignant form of the disease lose 

 practically all their milk: even when the disease is mild in 

 character the decrease will be from one third to one half 

 of the usual yield. If the udder becomes involved, the milk 

 has a slimy consistence and is yellowish and viscous like 

 colostrum. It frequently contains coagulated fibrin and 

 blood, so that a considerable sediment forms upon stand- 

 ing, while the layer of cream which rises is thin and of a 

 dirty color. The milk may even have a bad odor and a re- 

 pulsive, rancid taste. 



The disease is transmissible to man through ingestion of ' 

 raw milk, buttermilk, butter, cheese, or whey from dis- 

 eased animals. Occasionally the disease is transmitted 

 directly from the infected secretions. Children are not 

 infrequently infected by drinking unboiled milk during the 

 periods in which the disease is prevalent in the neighbor- 

 hood. 



The symptoms in children resemble those in the cow 

 very closely. There is fever, sometimes vomiting, painful 



