INOCULATION AS A PREVENTIVE OF SWINE DISEASES. 
71 
respondingly less. Leaving out of consideration the question 
of whether the hog, in case he survives the inoculation, is pro¬ 
tected from the disease, it is plain that an operation which is 
followed by four hundred deaths out of a thousand inocula¬ 
tions has not been sufficiently perfected to merit the confi¬ 
dence of the farmers. 
We will now turn for a moment to the question of the pro¬ 
tection by the operation. To what extent were the hogs in¬ 
oculated in Nebraska protected from the contagion, if really 
exposed to it? The advocates of inoculation tell us that it 
has been impossible for them to give the disease to their in¬ 
oculated hogs. Our experiments at Washington show that 
nearly all inoculated hogs can be afterwards fatally infected 
with cholera. Did the animals inoculated in Nebraska re¬ 
ceive any greater degree of immunity than those which were 
inoculated in Washington? 
The Board of Inquiry appointed by the Commissioner of 
Agriculture in 1888, procured a number of hogs that had been 
inoculated in Nebraska (about seventeen), and tested them by 
feeding them with cultivated virus of hog cholera and by in¬ 
oculating them with the virus of hog cholera and swine 
plague. In each case a number of the animals that had not 
received the protective inoculation were used in the experi¬ 
ments to determine the effect of exposure upon ordinary 
swine. The first test was made by feeding cultivated virus, 
but this did not prove strong enough to kill any of the hogs. 
Even those which had not been inoculated survived, but all 
of the hogs, including those that had been inoculated, were 
very sick. The inoculated hogs were not quite as sick as 
the others, but there was very little difference. Four of 
the inoculated hogs from Nebraska, and five hogs from Penn¬ 
sylvania which had not previously been inoculated, were then 
inoculated with the virus of the disease known as infectious 
pneumonia or swine plague. Of the four Nebraska inocu¬ 
lated hogs, three died and one recovered, but this one when 
subsequently killed for examination proved to be very severely 
affected. Of the five hogs which had not been previously in¬ 
oculated one died and four were sick and recovered. When 
