The progressive farmer. [volume] (Winston, N.C.) 1886-1904, 1897-09-28
WEEKLY DIGEST
Of Experiment Station Bulletins.
No. SO.
vACoINATING FOR HOG CHOLERA.

and their results in treating hog cholera
by vaccination, or rather by serum
therapy. By way Of introduction DE-.
Peters briefly explains the way in
which vaccination is supposed to oper-
ate as a protection against disease. 1t
is well known that one attack OF such
diseases as smallpox, measles, whoop-
ing cough, scarlet fever, etc, renders
the system immune against the same
disease for all future time, except in
rare cases of some individual peculiar
ity not yet we'll understood There are
other diseases an attack Of which rem
ders future attacks less likely to hap
pen and mLlder In form il they do hap
pen, and there are still others, the GER
tainty and virulence of which are not
affected by previous attacks, while
there are a few an attack Of which
seems to render future attacks more
certain and more virulent. For In
stance, an attack of malarial fever in
creases the susceptibility to another
attack.
Now it is well known that many dis
eases are causes and spread by bacteria
or living germs so small that they are
only seen by the aid of a powerful mi
croscope, and then, in some instances,
only after they have been artificially
colored pink or red. These germs are
really very small plants, similar 20 the
yeast plant, and the plant that causes
fermentation Of wine. In the process
of their growth and development these
little plants generate or give off certain
chemical substances which paraly re
their own powers. For instance, both
the yeast plant and ferment germs gen
crate alcohols and after they have pro-
duced alcohol of certain strength or
quantity their activity ceases, because
the alcohol paralyzes them for the time
being. If water be added to dilute and
weaken the alcohol, they agair become
active in growth and multiplication
till sufficient additional alcohol is gen
Grated to again render them inactive.
In like manner the germs of disease
produce some sort of chemical com
pounds that are poisonous to the per
sons or animals attacked, and the dis
ease lasts till these poisons become
strong enough to paralyze the germs
themselves. Then the disease is said
to have u it's course. Now if sum
Gent Of this peculiar POISON remains IN
the blood to paral. z3 all germs of the
same kind that may afterWard enter
the system, the person or animal will
never have another attack Of that die
ease. But if in the course OF time all
that particular poison Is eliminated
from the blood, q second attack may
be as severe as the first, If only enough
of the poison is elimated to weaken its
effect on the disease germs, the second
attack will be brief and mild.
Now it has been found that, in many
cases, If some Of this poison Vaccine vi
or serum) be injected into the blood
soon after the digeese germs have en-
tered the system, and before they have
had time to become very numerous or
strong By multiplication and growth,
the germs will DC paraly z9d and the
disease will be arrested.
These bacterial poisons are called
toxins, and the serum or virus injected
into the blood vessels by a small
syringe, OF by the Of a needle or knife,
are called anti toxins. The Watery part
blood or milk Is called serum. II blood
clots, the serum separates from the
clot in the form of a M re or less clear,
pinkish liquid. II milk cIots (3labber)
the serum separates from the curd in
the form Of whey. If serum from the
blood Of en- animal which contains
these poisOns is injected into the circu
lation of another, it is called q serum
treatment, o. serum therapy. If virus
is taken from an eruptive pustule and
introG uCed into the circulation of an,
other person or animal by pricking, it
is called vaccination.
The anti toxin serum is often obtained
from animals hat are naturally i'm.
mune. For instance, an OK will not
take CHAMBERS; neither will a horse take
pleuro pneumonia nor hog cholera.
Hence h germs Of hog cholera may
be safely injected into the circulation
OF a horse, and when they have filled
the horse serum with their anti toxic
poisons the horse may be bled, the
blood clothed and the serum used to
treat sick or threatened hogs.
Within late years scientists all over
the world have been testing the anti
toxin treatment, or serum therapy, for
all manner Of human diseases. and il
may be Interesting to sum I'D the re-