ETIOLOGY 7 1 



and specificalh- named as Bacillus boviseptiais hy Krnse. This 

 according to Migula's classification, should be Bacterium 

 bovisepticiun. A brief description of the organism as given by 

 Wilson and Brimhall is appended. 



" The organism has a strong tendency to show polar staining in tis- 

 sues and to form chains of much shortened individuals in liquid media 

 which causes it to be mistaken in examinations of a single specimen for 

 a diplococcus or a streptococcus. Sometimes in cover-glass preparations 

 from solid organs and very frequently in those from body fluids and 

 liquid cultures, the bacteria were found in chains of three to twelve indi- 

 viduals. In cover-glass preparations the bacteria are from 0.6// to 0.8// 

 broad and from i.o to 1.5'/ in length. In tissues which have been fixed 

 in 96 per cent, alcohol, they are somewhat smaller. In cultures, especially 

 in fluid media, they are apt to be much smaller and approach diplococci 

 in appearance. The ends are rounded. In stained preparations directly 

 from the tissues most of the bacteria have the ends intensely stained 

 and the central portion but faintlj- so. In some chains in rapidly grow- 

 ing broth cultures this is not the case, many of the individual bacteria 

 being evenly stained throughout and somewhat pointed at the ends. 

 They do not retain the stain by Gram's method. The organism is non- 

 motile. It is aerobic, but prefers the depths rather than the surfaces of 

 the media. It grows best at the body temperature and more slowly at 

 room temperature. In plain and dextrose broth a heavy growth appears 

 in 24 hours. In Dunham's solution a small amount of indol is formed 

 in 48 hours. No coagulation of milk. On Lofflers blood serum, direct 

 from the diseased tissues, it failed to grow well. On potato no appreci- 

 able growth has been obtained. In gelatin plates small, granular white to 

 slightly yellowish colonies appear after 48 hours. In gelatin stab cul- 

 tures a light growth occurs on the surface, while along the needle tract 

 numerous colonies like those in the deep portions of the plate cultures 

 develop. The bacteria are destroyed in fluids at 58° C. in 7 or 8 minutes, 

 by I to 5,000 mercuric choloride in i minute, and by a solution of lime 

 water as weak as 0.04 per cent, almost immediately." 



§ 59. Symptoms There is little opportunity to deter- 

 mine the sjmiptoms. The animals observed at the onset of the 

 disease by Wilson and Brimhall, appeared dumpish and out of 

 sorts. There is sudden stopping of the milk secretion in milch 

 cows. As a rule the affected animals refused food. Of the few 

 that make an attempt to eat, those with affected throats were 

 unable to swallow except with much difficulty. These cases 

 also breathed very heavih'. The animals showed marked disin- 

 clination to move and when incited to do so, exhibited stiffness, 



