Omaha daily bee., 1899-03-09
MAKING PORkERS IMMUNE
Results Of Experiments in Checking Hog
Cholera and Swine Plague,
MILLIONS LOST BY TIL: DISEASES
' Preventive serum Secured After EX-
tended Observation-Disclosures of In
oculntion-NnluubIc Facts
for Farmers.

WASHINGTON, March 6.-(Correspond-
ence OF The Bee,)-There is no disease atlct-
ing the domestic animals Of this country
which causes greater financial loss to the
farmers than hog cholera and swine plague
DR.. ID. f. Salmon, chief Of the Bureau OF
Animal Industry, estimates that Iowa alone
suffered to the extent OF $l5, 600, 600 in 1891
and for the same year the entire losses for
the entire country were estimated at 800,
100000. These figures are certainly not too
large; indeed it is highly probable that they
are not large enough,
There is therefore being put forth every
effort by the scientists to discover a cure or
preventive or both for this devastating dis
ease. First and foremost among the men
who are thus devoting their energies is Or.
f. A. de Schweintz, chemist of the Bureau
OF Animal Industry.
1t must be remembered that while hog
cholera and swine plague are alike to all
outward appearances, they are distinct dis
eases. produced by different kinds Of germs,
and affect the animal internally in a differ
ent manner, DR.. A. w. Biting of the In
diana experimental station says the germs
of hog cholera are longer than those of swine
plague and are more resistant to climatic
conditions They obtain entrance to the
body through food water and air; young
pigs are specially susceptible and may die
when older ones have a mild attack or escape
altogether The intestines are the primary
seat of hog cholera and the disease is more
readily communicated than swine plague.
The germs of swine plague are believed to
gain entrance to the body mainly through
the air. With this disease the older and
fatter hogs suffer the greatest fatality and
the lungs are the primary seat of the af-
fection.
Distinct Diseases.
DR.. de Schweinitz records positive evi-
dence of the difference between these dis
eases in bulletin No. %, just issued by the
Bureau of Animal Industry. However, both
diseases may occur together in the same ami
NAL. Two kinds of serum were prepared
the one having antitoxc, or curative, proper
ties for swine plague and the other
having curative properties for hog
cholera; and test was made
to ascertain if they could be used inter-
~ Changeably The result showed that the
VI hog cholera serum protected guinea pigs
Y upon which experiment was made) from the
cholera germ, but not the swine plague
germ, and that the swine plague serum pro-
tected or cured guinea pigs infected with the
swine plague germ, but not from the hog
cholera germ.
The preparation of this serum requires
from six to eight months. Cattle, horses,
mules or donkeys are injected with hog
cholera or swine plague serum, or with a
solution of the products Of these germs, in
Guiding cell contents, extracts and secre-
tions. The quantity injected at first is
small but gradually increased until large
amounts could be given without bad effects
1t is this treatment that requires so much
time and it must be done very carefully.
After all these injections and when the
serum is drawn its value is determined by
the amount of serum necessary to protect or
cure guinea pigs from hog cholera or swine
plague, which diseases have been supern-
duced in the guinea pigs by incubation with
the germs of the diseases. Its value is also
determined by injecting sufficient serum to
kill guinea pigs which are not immune, but
which will not affect those which are i'm
mune.
Owing to the facts which are stated above
that these are two distinct diseases and that
the serum for either one will not cure OF
prevent the other it became necessary to
prepare a mixed serum which should have
the curative properties OF both, and was
done successfully. This is very important
as 1t obviates the necessity of determining
which of the diseases is affecting the hogs.
Successful Experiments.
Experiments along these lines were re-
markably successful on a small scale, but II
was desirable to test the theory in a larger
A field. Therefore the governor of Iowa
NJ under authority given him by the legisla-
'iure. designated Page county as a field fol
operations against hog cholera and swine
plague, and the Bureau of Animal Industry
OF the Department of Agriculture took
charge OF the work in 1897 and continued il
through 1898. Although there were many
obstacles thrown in the way of the investi'
kgators the results were highly gratifying
y IN order to secure definite results not all Of
herd infected treated. The animal:
not treated were called checks. The mum
Der of animals treated during 1897 was 19
and 161. or about 50 per cent. was saved. II
the check herds were 42s animals and only
about 10 per cent recovered or, in othel
words, about So per cent was lost.
In 1898 the number of animals treated
wac TD7 with loss NJ a03 The mum heI