SWINE ERYSIPELAS 85 
very closely related to the bacterium of mouse septicemia described 
by Koch in 1878. There is much uncertainty concerning the relation- 
ship of the bacterium of mouse septicemia to that of this disease. 
Smith has suggested that possibly the bacterium which has been 
found in this country may gain virulence sufficient to produce epi- 
zootics, if such is not already the case. It is exceedingly important 
that careful search be made for this organism in the outbreaks among 
swine where the nature of the disease is not clearly determined. 
House mice and pigeons are susceptible to the bacterium of swine 
erysipelas; guinea pigs and fowls are immune. The bacterium of 
swine erysipelas is to be differentiated from that of mouse septicemia. 
The period of incubation is stated to be at least three days. It is 
apparently longer than that in many cases. 
Symptoms. The disease usually begins suddenly and violently. 
The animal refuses food, makes efforts to vomit, has a rise of tempera- 
ture, manifests severe nervous disturbance, is very weak, torpid and 
indifferent to its surroundings. When approached it tries to hide 
itself under its bedding. The hind quarters become weak and 
paralyzed. Muscular spasms and grinding of the teeth are sometimes 
observed. At first there is constipation, the conjunctiva is of a dark 
red or brownish-red color, and the eyelids are sometimes swollen. 
Usually a day or two after the first symptoms develop, or, perhaps, 
from the first, reddish spots appear on the thin parts of the skin, 
such as the region of the navel, lower surface of the chest, perineum, 
inner surface of the thighs, ears and throat. These spots, which 
at first are bright red and about the size of a man’s hand, become, later 
on, dark red or purple, and soon unite into large, irregularly-shaped 
patches. As arule, they are neither painful to the touch nor promi- 
nent, but sometimes they show a slight inflammatory swelling. The 
skin of the red spots, especially of the ears, may suffer from an erup- 
tion of vesicles and may even slough. Gangrene of the skin sometimes 
occurs. The reddening of the skin may be very slight in severe cases, 
or may appear only immediately before, or even after death. Death 
takes place usually on the third or fourth day. In the very severe 
form, the animal may die in twenty-four hours, otherwise the disease 
requires a week or longer to run its course. 
Jensen considers that this disease, instead of being uniform in its 
clinical aspects, manifests itself in the following forms, which differ 
from each other by well-marked peculiarities. The forms recognized 
