PREFACE 



This work is based upon the investigation of milk of 

 diseased udders and the subsequent autopsy of such dis- 

 eased udders. 



The material for these examinations consisted princi- 

 pally of samples of milk and specimens of udders sent to 

 the High School for the investigation of tuberculosis. 



In addition to this material, milk samples were obtained 

 from acute udder-afFections which were not tuberculous. 

 Most of the material examined, however, was of a tuber- 

 culous character. The mmiber of non-tuberculous udders 

 amounted to ca. 50. 



In order to study the kinds of udder-infections to be 

 taken up not less than seventy bacterial isolations were 

 made from milk and udders by the plate method. The cul- 

 ture medium was sermii-gelatin-agar or sermn-agar. Gela- 

 tin plates were poured in only a couple of cases and then 

 for a special purpose. 



For study of the histological changes in the diseased 

 udders thirty different preparations were examined. Most 

 of them were cut with the freezing microtome immediately 

 after fixation in formalin. The remainder, ca. 10 cases, 

 were cut after imbedding in paraffin. The sections were 

 stained with haematoxylin and eosin or after the method of 

 Van Gieson. In order to study the bacteria the sections 

 were stained with carbolmethylene blue or after the method 

 of Weigert or Ziehl. 



Concerning the clinical description I am supported by 

 clinical material from my veterinary practice (35 cases), 

 and upon the cows with udder tuberculosis, purchased by 

 the Veterinary High School, in which I produced mastitis 

 by artificial infection. In addition other veterinarians have 



