FIFTEENTH ANNUAL YEAR BOOK — PART VI 429 



while persons in charge of diseased animals may become infected 

 through contact with the diseased parts or by milking, slaughtering, 

 or caring for the animals. 



The disease is very seldom fatal to human beings, usually ap- 

 pearing in a very mild form except in w^eakened children, in whom 

 an accompanying intestinal catarrh may lead to a fatal termina- 

 tion. 



An animal in the first stages of the disease, or with a slight at- 

 tack, will produce milk which is only slightly abnormal. There is 

 generally a reduction in the quantity of sugar and casein, which 

 causes a reduction in the specific gravity. "When the disease is 

 fully developed, the milk invariably contains inflammatory products 

 of a very pronounced character and the quantity of milk is greatly 

 reduced. Cows affected with malignant form of the disease prac- 

 tically fail to produce milk. 



If the udder becomes involved the milk becomes slimy and is 

 yellowish and viscous like colostrum. It may contain blood and 

 deposit a sediment on standing; the cream layer is thin and of a 

 dirty color. Sometimes no cream layer is formed, the milk ap- 

 pearing uniform but slimy and possessing a bad odor and repul- 

 sive rancid taste. 



On account of the possibility of the disease being transmitted to 

 human beings as well as to animals, through the use of milk and its 

 products, it is advisable that all milk, cream, skim milk, and butter- 

 milk be efficiently pasteurized. The bacteria causing the disease 

 loses its virulence by being heated to 122° F. for 15 minutes ; by 

 being heated to 158° F. for 10 minutes; heating to boiling destroys 

 it at once. The bacteria is not easily killed by cold and has been 

 known to remain active after being placed in a refrigerator for 

 one month. 



As a means of safeguarding the health of the people through 

 the milk supply of the state, as well as for the protection of the 

 dairyman and his herd, the Commission makes the following recom- 

 mendations : 



ALL FARMS FOUND TO HAVE DISEASED ANIMALS 

 MUST BE IMMEDIATELY QUARANTINED AND NO MILK 

 OR DAIRY PRODUCTS THEREFROM PERMITTED TO BE 

 USED FOR ANY PURPOSE AVHATSOEVER. 



CREAMERIES MUST THOROUGHLY PASTEURIZE ALL 

 CREAM, MILK, SKIM MILK, AND BUTTER-MILK. 



