188 SPECIAL BACTERIOLOGY 



In Bouillon containing sugar, gas is formed. 

 Milk is not coagulated. 



Pathogenesis. Very virulent for white and grey house mice,, and 

 for field mice (arvicola arvalis) both by subcutaneous injection and by 

 feeding. The infection is spread by the living mice eating the bodies 

 of those dead of the disease. Loffler, owing to this circumstance, used 

 the cultures in destroying the mice during the plague in Thessaly. 



SWINE FEVER. 



(Pneumo-enteritis Klein. Ger. Bacillus der Schweine Pest. 

 America, Swine Plague Billings; Hog Cholera Smith). 



The chief veterinary officer, in his report to the Board of Agri- 

 culture for 1896, states: ''It is quite certain that the disease which 

 exists among the swine in America, where it has received the name of 

 hog cholera, is identical with our swine fever, because in the year 1879 

 some cargoes of pigs affected with hog cholera were landed at Liverpool, 

 when an opportunity was afforded of identifying the lesions of that 

 disease with swine fever? 



The above conclusions are identical with those published by the 

 writer in 1891, when cultures were obtained from an outbreak of 

 swine fever in England, and sent to Billings in America, who wrote 

 that he had made all the tests and control experiments, concluding as 

 follows : ' It is the same germ as we have here as the cause of hog 

 cholera." 1 



Microscopical Appearances. Short bacilli 1-2 to 1-5 /* long, and 

 0-6 to 0-7 p broad. 



Motility. Strongly motile ; possessing a multitude of flagella, 

 something like the Bacillus typhi abdominalis peritricha (see Photo- 

 micrograph, Plate III., Fig. 13). 



Staining Reactions. Stain easily with any of the usual aniline 

 dyes. The Gram method gives negative results. When freshly obtained 

 from an animal, the condition known as bipolar staining is well-marked 

 (see Photomicrograph, Figs. 68, 69, 70), the clear unstained centres 

 not being so easily differentiated in older cultures, or if the staining 

 process is too long continued. In sections of organs the bacilli are 

 present in the capillaries and small veins. 



Spore Formation absent. 



Vitality. It is destroyed by a temperature of 58 C. in from fifteen 

 to twenty minutes. It preserves its vitality in spite of desiccation for 

 nearly two months, and vegetates and multiplies at the ordinary tern- 



