152 MASTITIS OF THE COW 



firm but friable consistency and about the size of an egg. 



The lobuli showed the same alterations here as those in 

 the yellowish-gray part. Yellowish fibrin was found in 

 the milk canals and cisterns. Other parts of the udder 

 presented no lesions. 



A comparatively great number of clumpy Gram nega- 

 tive bacilli showing rounded ends were found in the fibrin 

 and in scrapings taken from the red parts (colon bacilli). 

 The diagnosis was corroborated by cultures. 



D. PYOBACILLOSIS 



1. Pyobacillosis in both posterior quarters. 



Both posterior quarters of the udder were moderately 

 swollen. Their consistency was firm. The lymph-glands 

 were slightly enlarged. 



Both quarters showed the same lesions. The incision 

 was covered by thick yellowish-green pus. The lower part 

 of the cut surface was even, grayish-white and firm. The 

 lobuli showed no milk points, but small yellow pus foci. 

 Yellow cylinders of pus were expressed. Yellowish-green 

 pus foci ranging in size from a hemp seed to a bean were 

 observed here and there. They presented a faint, disagree- 

 able odor (not putrefaction) and were surrounded by a 

 white, firm, tough connective-tissue capsule. A few milk- 

 ducts were thickened and formed large irregular cords 

 which, on cross section, presented a yellowish-green centre 

 of pus surrounded by a firm, white connective-tissue cap- 

 sule, and outside of that by thickened lobuli. Yellow, 

 spongy fibrin was found in the teats and milk-ducts. Other 

 parts of the udder presented no lesions. 



A great number of small, thin Gram positive bacilli 

 were found in the yellowish-green pus (pyogenes bacilli). 



2. Pyobacillosis in the right half of the udder as well as 

 in the left posterior quarter. Complication xmth gangrene. 



