634 MICROBIOLOGY OF THE DISEASES OF MAN AND ANIMALS. 



and formic acid, are supplied to the bees in syrup, and these being anti- 

 septic prevent the growth of the bacillus. In advanced cases, and 

 when the queen bee is affected these methods usually fail. Disinfection 

 with formalin gas has been used with good success. 



MALIGNANT (EDEMA.* 

 Bacillus cedematis maligni. 



The disease occurs as the result of infection of wounds with dust or 

 soil. The wounds must involve the tissues deeply as in compound 

 fractures and deep cuts. 



Any animal may be infected, although the dog and cat are said to be 

 rather more resistant than others. 



The incubation period is short, from one to two days as a rule. 



The usual case begins with sudden spreading haemorrhagic sub- 

 cutaneous oedema and high fever. Practically no gas is formed. The 

 fluid shows bacilli both with and without spores. Where soil contamina- 

 tion exists, mixed infections with gangrene are common. 



Pasteur in 1877 and Koch and Gaffky in 1881 found and studied 

 rhe organism and by passing from animal to animal established the causal 

 telationship. 



Glucose agar or glucose gelatin is inoculated with the suspected fluid, plates 

 poured and placed under anaerobic conditions. The organism is o.Sfi to i/j. wide. 

 Filaments may occur. The rods without spores are uniform in width with slightly 

 squared ends. They are usually single, though pairs end to end are frequent and 

 chains are also found. Oval spores are formed somewhat variable in their position, 

 with a diameter usually larger than that of the vegetative rod, bringing about a spindle 

 shape. Peritrichic flagella have been demonstrated, about twenty in number. It 

 stains readily with aniline dyes, usually Gram-negative though somewhat variable and 

 indefinite in this regard. Growth takes place at both 20 and 37. It is a strict 

 anaerobe. Like anaerobes in general it prefers the presence of a fermentable carbo- 

 hydrate such as glucose. On agar the colonies are small, whitish, and irregular in 

 outline. Gelatin and blood serum are digested, caseinogen is changed to casein which 

 is then digested. In both protein and carbohydrate media a gas is produced which 

 has a very disagreeable odor. The spores are very resistant. 



This resistance accounts for its continuous presence in earth and dust 

 and as a constant inhabitant of the intestine of animals, especially of 

 herbivora. 



* Prepared by Edward Fidlar. 



