296 VETERINARY BACTERIOLOGY 



readily in culture-media at room-temperatures. Acid is produced 

 from saccharose and dextrose, but not from lactose; gas is never 

 formed. No proteolytic enzymes are produced. Indol and 

 phenol are formed in Dunham's solution. 



Pathogenesis. Experimental Evidence. The B. avisepticus 

 is pathogenic for chickens, geese, pigeons, and other birds, mice, 

 and rabbits, producing a rapidly fatal septicemia when intro- 

 duced subcutaneously. When fed, it will also produce disease in 

 these animals. Guinea-pigs appear to be relatively immune, 



p 

 Fig. 120. Bacillus avisepticus, in pigeon's blood (Frankel and Pfeiffer). 



except when injected with very large doses. It is not known to 

 produce disease in man. 



Character of Disease and Lesions Produced. When introduced 

 subcutaneously, there is an extensive edema at the site of inocula- 

 tion, generally accompanied by more or less hemorrhage. The 

 spleen and liver are swollen and congested, the lungs have congested 

 areas, and the intestines show an inflamed mucosa, with occa- 

 sional ulcer formation. Minute hemorrhages are found in various 

 organs, particularly the lungs, the walls of the intestines, and the 

 heart. Feeding experiments result in a localization of the lesions in 

 the intestines. Areas of necrosis are frequently found in the liver. 



