The Iola register. [volume] (Iola, Allen County, Kansas) 1875-1902, 1891-05-22
TEXAS CATTLE FEVER.
THE DISEASE ATTRIBUTED TO TICKS
BY THE DEPARTMENT OF AGRI-
CULTURE.
The Conclusion Reached After Extended
Experimenta.

CULTURE.
The Conclusion Reached After Extended
| Experiments.
A recent dispatch to the st. Louis
Globe-Democrat says that the depart
ment of agriculture has found out what
causes Texas cattle fever. This has
long been mystery. Various theories
have been advanced and combated.
The department has been conducting
experiments for several years, and now
the announcement is made with good
deal of confidence that the Texas fever
is due to ticks. The experiments have
been made by taking different fields.
"One Of these fields" says the report,
contained North Carolina cattle with
the ticks: second, Texas cattle with
ticks; third, North Carolina cattle
without ticks: fourth, ticks only, and
fifth, soil from the pastures of infected
| North Carolina farms. Other fields
were also laid out to test questions
which need not engage our attention in
this brief survey. The results confirm
ed those of last year. The first animal
to die was in the tick field containing
no southern cattle. No disease appear
ed in the soil of the field. Unfortunate
ly, owing to the limited space Of ground
at our disposal and its barren, rolling
character, ticks or eggs were washed
during the heavy rains Of the summer
from the tick field into the field con-
tanning southern cattle without ticks,
although wide lane interviewed. The
natives in this field thereupon all died
of Texas fever. AT the autopsy of these
cases ticks were found attached to their
skin in abundance. The disease caused
by Texas cattle could not be distinguish
ed in character from that which was
produced by North Carolina cattle.
These results similarly pointed to ticks
as the cause. The precise manner in
which they caused the disease was by
no means clear, however. The theory
which seemed for time most accepta-
BILE was that the adult ticks, as they
dropped off, infected the pastures with
germs which they had taken in with
the blood of the southern cattle. and
that the germs were introduced into
the body of northern cattle with the
food.
'At the same time no parasite could
be detected in the blood of southern cat
tie examined at various times, on which
fact would lay no more stress, however.
OF more Importance is the popularity
which is exhibited by this disease in its
period of incubation as it may be provi-
sionally denominated, and which is op-
posed to this theory. Thus. when native
and southern cattle are placed on the
same pasture at the same time it will
take from forty to sixty days for the
disease to appear. After disease has once
shown itself. fresh animals placed in
the same pasture may die. according to
our experience, within thirteen days
after the beginning Of the exposure.
We might say the virus has to 'ripen'
on the pasture, which takes nearly two
months, depending on meteorological
conditions. When once 'ripened' this
virus does its deadly work within two
or three weeks. This explanation, how
ever, would be merely formulating our
ignorance concerning the true nature OF
the infectious principle To the writer
drawn from the facts, and that is that
the young ticks drop from the southern
cattle and the eggs laid by them develop
into young ticks. After that period
young ticks are present on the pastures
until they are destroyed by the cold, or
until the cold interferes with
the development of the en-
bryo in the eggs. In other
words, the period Of incubation Of the
disease is explained without any diff
Guilty by the life history Of the tick
The question was solved experimental
ly, in the following manner: Eggs laid
by ticks sent from North Carolina were
placed on dried leaves in dish partly
filled with moist soil and kept in the
laboratory until the young emerged
from the egg. The period of incuba-
ton depends entirely upon the relative
amount OF heat, and has varied from
fifteen days in midsummer to forty
days in November when the rooms of
the labatory became cold at night.
These ticks were placed on four differ
ent animals Of different ages, kept
away from any infected Enclosures. |
Two were placed in stalls, one of them |
on an adjoining farm, and two were |
to stay in patch OF wood land |
with healthy cattle. OF these four two |
died with Texas fever, as determined |
by careful postmortem examination. |
One of them was in the stall away from |
the station, the other 10 the patch of
woodland. The other two became very |
ill: one of them never recovered, but |
had to be killed later On; the other re.
covered. In all of them the germs
were observed in the blood. The d.
sease possessed the same characters
tics as those observed in cattle in the
infected pastures during the summer.
There was an elevation of temperature
from nine to twelve days after the
young ticks were placed on the animals,
going as far as l07 fahr in one animal.
the fever a gradual re-
1uction in the number of blood corpus
lies was Observed"
Rroinad Her uusband