The Mitchell capital. (Mitchell, Dakota [S.D.]) 1879-1918, 1908-01-31
SPREAD OF TUBERCULOSIS
AMONG CATTi .

SPREAD OF TUBERCULOSIS
AMONG CATTLE.
From the Farmer and Breeder.
AS a result OF the observations OF
many cattlemen aud a large number OF
Investigators, it has been known for
many years that tuberculosis will
spread more or Less rapidly in q herd
OF cattle upon the introduction of tu-
bercular animals. But in order to get
some specific data upon this point Or.
D.. e. Salmon, chief of the Bureau of
animal industry. had the following in.
Vestigations conducted at the bureau
experiment station. Washington. D. c.:
on January q. 1903, seven healthy
cattle and three tuhercular COWS We're
placed together IN a stable containing
ten box stalls. The stalls were sepa-
rated by solid two-inch plank parti.
tons six feet high. Five of the healthy
cattle and the three disc ased COWS oc.
cupied different stalls AGA day in such
rotation that each healthy animal was
equally exposed to the three tubercular
ones. While the other two healthy
animals occupied stalls near the cen
Ter OF the stable and We're at no time
allowed TO enter other stalls or to come
into closer contact with II of the
other cattle.
On April 10, 1903, one of the three tu-
bercular cows was removed from the
stable and two more severely affected
COWS were introduced.
On June II, 1908. one of these last two
COWS was ound dead and a post NOR
tenn examination demonstrated that
she had died of tuberculosis.
OF the five tubercular cows used In
this investigation the only ones that
were in an advanced stage of the dis
ease were the two that were placed in
the stable on April 10, 1908. while in the
other three the disease was not sutli-
GENTLY advanced to present any marked
symptoms.
The seven healthy cattle were all
tested with tuberculin, and known to
be free from tuberculosis when placed
In the experiment.
The two animals. one q yearling bull
and one 6-year-old cow, that We're kept
in their regular stalls and exposed only
by being kept in the stable with the
other cattle. were killed August 3, 1908,
1873 days after the experiment began.
And both were found upon post mortem
examination to be affected With tuber-
culosis.
OF the other cattle that had been
stabbed In rotation In III stalls that
We're occupied by the diseases animals.
one an 18-months-old heifer and one a
6-months-old heifer calf, were killed
August 3 and 5. 1903, or 1888 and 1871 days
after being placed in the experiment.
Upon post norton examination they
were found to be affected With tubercu-
i'OoLS. NllllS liC oSIle llIGe VI lIS
healthy animals, Il mich COW and two
yearlings, a bull and a heifer, We're
animals that had previously received
immunizing treatment somewhat after
The Won Behring method. This treat
Inent consisted of an injection into the
blood vessels Of Il solution of dead
itubercular bacillt from a human source.
Each animal had been given one in
lection in July. 1902. and tine cow two
more in August, one in September and
one in October, 1902. The young cat
tie received one treatment and the
COW five. This treatment was supposed
10 immune or at least render the nj
mails more refractory to tuberculosis
than cattle that had not received such
treatment. Two of these animals We're
killed August 3 and the other August
b. 1903. All presented esion OF tuber-
culosfs upo post mortem examination,
Thus it will be seen hat all of the
v healthy animals contracted the
disease by being stabbed in the same
barn With tubercular animals for a PEE
Rod OF 18S to l91 days. Although extra
precautions had been taken with two
In that they were not allowed to stand
in amy stalls where the infected ami
mails had stood. and an attempt had
been made to imnluniZe three of the
others. so that only two of the ami
mails We're kept under conditions such
as usually prevail upon the ordinary
farm.
rms investigation demonstrates two
facts: First. that the disease may
spread in a healthy herd with startling
raptdity, and, second, that Won Beh-
rings method of immunization has not
us yet been sufficiently worked out to
oe of much, If any, value
1t is not common for the disease to
spread within Ii herd as rapidly as it
lid i'm this herd, yet this demonstrates
that it is possible for the disease to
spread very rapidly under certain con-
ditions, and consequently no one would
be able to state that the disease would
not spread rapidly in Il herd until it
was known that the disease had existed
I'm the herd for some time. And farm
@rs should not lose sight Of the fact
that their herd might be one in which
the disease might spread rapidly il it
was once introduced.
With these facts before US we cannot
TOO enphatically urge cattle raisers to
be very careful about introducing tu-
bercular cattle into their herds. An
other fact that should not be lost sight
of is that it is much easier and cheap
er to keep the disease out of your herd
thar it is to rid your herd of it after
II has once been introduced. Hence
we would caution all cattle raisera
o buying cattle from sources that
are liable to be diseased. In this con-
nection attention is called to the arti-
Gle, Some Contagious Diseases in
Farm Animals" that appeared in the
FEBRUARY II. 1905. issue of this paper.
THE HORSE TO RAISE.
The farmer raises horses for nroh+