UDDER-ACTINOM YCOSIS 1 1 1 



cotic foci up to the size of a walnut, while the foci in the 

 lymph-glands were the size of a pea. 



Metastasis by the milk plays a greater part and will 

 be discussed later. Metastasis by the blood-stream appears 

 to be quite rare. Actinomycosis of the lungs is somewhat 

 infrequent, while actinomycosis of the tongue and jaws is 

 common. 



Growth of Actinomycomata. — The primary actino- 

 mycoma manifests a very gradual development. The 

 central colony is very slowly enlarged. During the lacta- 

 tion period development is more rapid, but is slower during 

 the quiescent state. 



Neighboring actinomycomata, as primary foci, and their 

 daughter foci may coalesce by extension and produce 

 nodules ranging in size from a pea to a walnut or larger. 

 These nodules are composed of soft connective tissue and 

 numerous foci containing evenly distributed actinomycotic 

 colonies. 



Secondary Alterations of Actinomycomata. — 

 When great quantities of fluid are present, especially when 

 an actinomycoma has destroyed a milk-duct and thus is 

 brought in direct contact with the milk, the actinomycoma 

 can soften, disintegrate, and become a viscid, purulent, 

 slimy, thick fluid. 



Conversely when little fluid is present the actinomyces 

 colonies develop so slowly that the connective tissue of all 

 the actinomycoma proliferates very vigorously, more or less 

 circumscribing the infection by encapsulation. Under such 

 conditions the actinomyces colony can undergo retrogressive 

 metamorphosis, become partially or entirely necrotic and 

 finally be transformed into a concrement by calcification. 



Actinomycomata by their development appear to off'er 

 an obstruction to the blood circulation and to the milk flow. 



Ulceration of Milk-ducts. — Actinomycomata may 

 destroy the wall of a milk-duct. By absorption of milk 



