INOCULATION AS A PREVENTIVE OF SWINE DISEASES. 
69 
We inoculated about fifty animals in this way in our first ex¬ 
periments, varying the doses somewhat, and only five of them 
resisted the first exposure. By giving two inoculations we, 
of course, get a greater degree of protection than can possibly 
be obtained from one inoculation, with safety to the animals, 
but the expense of two inoculations is so great that, in order 
to make the method practical, the inoculator gives only one 
dose and generally increases that beyond the limit of safety. 
Thus, in some experiments that have been made in the West, 
I am informed that a dose of i cubic centimeter, i. e., from 15 
to 20 drops, was given, and many herds contracted the dis¬ 
ease and died, as should have been anticipated from the ex¬ 
periments previously made by the Bureau of Animal Industry. 
In view of these facts, when any one comes before the 
farmers of the country and recommends inoculation, it is well 
to inquire whether he is interested in the operation from a 
pecuniary point of view. The question as to how much the 
farmer will save by the adoption of this method of prevention 
is uncertain, and opens a wide field for discussion, but the 
sum it will be necessary for him to pay out to the experts 
who must be employed can be very accurately figured. This 
is one of the most practical aspects of the question and should 
under no circumstances be overlooked. 
It has been asserted that as many as one hundred and four 
hogs have been inoculated in seventy-two minutes. At a cost 
of 50 cents a head, which is the amount now charged for in¬ 
oculation, this would reach the sum of $43.33 an hour for the 
services of the inoculator, which certainly appears to be more 
than those engaged in the hog-raising industry can afford to 
pay for professional assistance. 
Should inoculation be generally adopted in the States in 
which hog raising is most largely carried on, it would require 
at least fifty men working five hours a day to comply with 
the demands. These men, inoculating eighty hogs an hour 
each, would inoculate a total of twenty thousand hogs a day, 
which would yield a daily revenue of $10,000. The total cost of 
hiring fifty men and maintaining a laboratory to supply virus 
would hardly exceed $300 a day. Putting the expenses at 
