IMPORTANCE TO MILK CONTROL 141 



2. Application of rules: 



a. Acute infections. 



Diagnosis. 



Test to determine disappearance of infection. 



b. Typical chronic infections. 



Diagnosis. 



Slaughter of animals. 

 Suspected chronic infections. 

 Time between examinations. 

 2. Milk as food for animals. 



The chronic udder-infections have a great economic significance 

 in regulating milk control. The animals may produce a consider- 

 able quantity of milk which can be of normal appearance, while at 

 the same time this milk cannot be used as food for man. 



These infections are very common as may be seen by the fol- 

 lowing figures compiled at an abattoir: In the year 1905 there 

 were inspected in the abattoir at Malmo 6936 cows, of which 

 1042, or 15 per cent, were shown to be affected with mastitis 

 (annual report of the Malmo Abattoir for 1905, edited by A. M. 

 Bergman, director). 



These cases of mastitis or udder-infection in abattoirs are 

 nearly always chronic. The acute infections are seldom seen 

 during the quiescent state of the udder, and cows are only slaugh- 

 tered in the lactation period when circumstances demand imme- 

 diate slaughter, which is very rare with acute udder-infections in 

 abattoirs. 



These cases of mastitis, or better, the chronic udder-infections 

 in the abattoirs, are chronic streptomycosis or pyobacillosis. 

 Udder-tuberculosis or udder-actinomycosis is usually listed in the 

 abattoir records under the head of tuberculosis and actinomycosis, 

 not as mastitis. In the report referred to above the cases of 

 udder-tuberculosis were computed with the figures on mastitis. 



Fifteen per cent, of the cows had been affected with chronic 

 udder-infections. 



The same report in 1905 showed 155 cases of udder-tubercu- 

 losis, which is ca. 2.2 per cent, of the number of cows slaughtered. 



Figures from the journal of the Veterinary High School for 



