666 Actinobacillosis. 



character in Argentine, sometimes 50% of all animals in a herd becom- 

 ing affected in the course of a few weeks. As a rule, however, the 

 disease occurs more or less sporadically. It has also been observed 

 in a Rambouillet ram by the same authors, while Nocard and Petit 

 observed it in France, Bongert in Germany and Higgins in Canada 

 among cattle. 



The clinical symptoms and anatomical changes are almost precisely 

 the same as those of actinomycosis bovis. As in the latter disease the 

 most frequent lesions consist of large, firm swellings gradually under- 

 going softening in the center, occurring in the skin and in the sub- 

 cutaneous connective tissue of the pharyngeal region; so called woody 

 tongue and polypous swellings of the pharynx constitute the most 

 frequent lesions. The jaw bones, the udder and the lungs are much 

 more rarely affected. On the other hand, however, the lymph glands 

 and occasionally some of the salivary glands are involved. Simul- 

 taneously with the development of the local changes the animals suffer 

 in their general nutrition and when tumors are present in the pharynx 

 or in the pharyngeal region, the disturbance of nutrition and respira- 

 tion may become so great that the affected animals finally succumb 

 to the effects of inanition. 



In the purulently softened foci of the tumors are found granules 

 varying in size up to that of a millet seed, readily visible to the unaided 

 eye, but in contrast to the colonies of actinomyees they are grayish- 

 white in appearance. Slightly yellowish and occasionally also calcified 

 granules occur exclusively in the sarcoma-like tumors of the maxillae. 

 Fresh pus examined under the microscope contains club-like structures 

 which are branching at the larger end, the pointed ends converging to 

 form radiating colonies which, however, contain no mycelium centers. 

 These structures are easily stained with acid dyes or with picro-carmine- 

 glycerin. On the other hand they do not take Gram's stain nor can 

 threads of mycelium be demonstrated in the pus. 



Pus triturated in a mortar and inoculated in alkaline food media, 

 when kept at body temperature for 24 hours, will produce small, glisten- 

 ing colonies of a small bacillus hardly exceeding that of fowl cholera 

 in size, forming long chains in bouillon and not staining after Gram. 

 Cultures on agar resemble those of the typhoid bacillus. This bacillus 

 acidifies -grape sugar agar and milk, but does not coagulate the latter. 

 The indol-reaetion is not pronounced. Fluid cultures contain toxins 

 which, when injected into cattle, produce an elevation of temperature 

 of from 1 to 2.5° C. persisting for several hours, trembling and loss 

 of appetite. The cultures are only slightly resistant to the influence 

 of external agencies. Simple drying or heating to 52° C. destroys 

 them rapidly. Grown at 37° C. in the thermostat they are gradually 

 attenuated. 



Bacilli injected under the skin of cattle collect in small groups 

 in the bodies of the leucocytes from which they subsequently escape 

 and develop into characteristic actino colonies. The center of these 

 colonies, the "germinative zone" consists of small bacilli which are 

 held together by a sticky substance while the outer zone consists of 

 club-shaped projections which continue to grow and undergo digitate 

 branching ("vegetative zone"). 



Pathogenicity. In guinea pigs intraperitoneal injection of bouillon 

 cultures produces purulent peritonitis with characteristic colonies in 

 the exudate, while subcutaneous injection is followed by the formation 



