INFLUENCE OF DISEASE UPON MILK 97 



and also to cattle and swine. It may also be transmitted 

 by butter and cheese. Man may be mildly or severely 

 affected; in some instances, the disease has terminated 

 fatally. The symptoms are fever, weakness, conjuncti- 

 vitis, nausea, vomiting, and diarrhoea, with formation of 

 vesicles on the mucous membrane of the lips, mouth or 

 nose, and on the ears, fingers or other places on the body; 

 sometimes the skin is red and the joints painful. 



The sale of milk from herds in which foot and mouth 

 disease exists should not be permitted, unless it is heated 

 sufficiently to destroy the virus and is not changed in 

 appearance. The virus is not very resistant. A tempera- 

 ture of 50 C. (122 F.) for 15 minutes; 70 C. (168 F.) 

 for 10 minutes; or 85 C. (185 F.) momentarily will 

 destroy it (Ernst). 



COWPOX 



Cowpox is closely related to variola or smallpox of 

 man. Before vaccination was introduced, when smallpox 

 frequently became epidemic, it is very probable that cow- 

 pox often originated from this source. Vaccinia of man is 

 also transmissible to cattle and many instances are on 

 record in which cows have been infected by vaccinated 

 persons. Infection takes place during milking as a rule, 

 the contagion being rubbed into the skin of the teat by 

 the hands of the milker. The disease is therefore most 

 commonly seen in cows in milk. It usually begins with a 

 rise of temperature, but this may pass unnoticed unless 

 it is accompanied by dullness and loss of appetite, as is 

 sometimes the case. The teats and neighboring parts of 

 the udder become swollen, hot, and painful. In two or 

 three days, papules appear, which may be as large as a 

 pea and which are surrounded by a red area. On the 



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