142 MASTITIS OF THE COW 



examination of udder-tuberculosis show us the occurrence of 

 chronic udder-streptomycosis, udder-pyobacillosis and udder- 

 actinomycosis. 



In 1905 and 1906 there were observed: 



Streptococci in 192 milk samples 



Pyogenes bacilli in 56 milk samples 



Actinomyces fungus in 10 milk samples 



Total 258 milk samples 



Taking these figures as a standard the above-mentioned cows 

 had: 



ca. 9.5 per cent. Chronic udder-streptomycosis. 

 ca. 2.8 per cent. Udder-pyobacillosis. 

 ca. 0.5 per cent. Udder-actinomycosis. 



Total, 12.8 per cent. 



If the percentage of udder-tuberculosis be added we have the 

 following figures: The 6936 cows slaughtered in Malmo in 1905 

 showed : 



ca. 9.5 per cent. Chronic udder-streptomycosis. 



ca. 2.8 per cent. Udder-pyobacillosis. 



ca. 2.2 per cent. Udder-tuberculosis. 



ca. 0.5 per cent. Udder-actinomycosis. 



Total, 15 per cent. Chronic udder-infections. 



These figures suggest how common such udder-infections are. 

 One should assume that these figures apply to every standard of 

 cow, but should consider that the statistics were compiled in an 

 abattoir and that they only include animals slaughtered for vari- 

 ous reasons such as old age and disease. 



According to the estimate of a practical farmer ca. 16 per 

 cent, of the cows must be slaughtered yearly under ordinary cir- 

 cumstances. 



The 6936 slaughtered animals mentioned, according to these 

 figures, would indicate a total of 43,350 cows. 



