markets. In addition to this, the increase in prices of cattle sold locally
in the South would represent a large sum. This local increase has been
found to amount to from $3 to $15 a head in territory freed from ticks. An
agricultural official of one of the Southern States has reported that
calves in the tick-free area bring double the prices that can be obtained
for similar calves in the tick-infested region.
Heretofore it has been impracticable to improve the quality of southern
cattle by introducing fine breeding animals from other sections, because
such animals were liable to contract Texas fever and die unless protected
by inoculation. Furthermore, it is impossible for animals to attain good
growth and to thrive when they are heavily infested with ticks. With the
eradication of the ticks, however, the southern farmers are enabled to
introduce good breeding animals and to improve the grade of their stock.
There is no longer any doubt that it is entirely practicable to exterminate
the ticks throughout the entire region, and the accomplishment of this
result will be of tremendous economic advantage not only to the South but
to the whole country. The rate of progress depends mainly on two factors--
the amounts appropriated by the Federal and State Governments, and the
cooperation of the people.
* * * * *
SOUTHERN CATTLE FEVER (TEXAS FEVER, TICK FEVER).
DESCRIPTION OF PLATES.
PLATE XLIV. Normal spleen and spleen affected by Texas fever.
Fig. 1. Spleen of an acute, fatal case of Texas fever. The narrow end of
the spleen is here represented.
Fig. 2. Spleen of healthy steer. Though the latter animal weighed one-half
more than the former, the weight of the diseased spleen (6-7/8 pounds) was
nearly three times that of the healthy spleen (2-3/8 pounds).
PLATE XLV. Texas fever.
Fig. 1. The cut surface of a healthy liver taken from a steer slaughtered
for beef.
Fig. 2. The cut surface of the liver in Texas fever.
Fig. 3. Appearance of the urine in an acute, fatal case of Texas fever.
Fig. 4. Red corpuscles, magnified 1,000 diameters, containing the parasite
of Texas fever. This appears as a blue point _a_ near the edge of the
corpuscle. The blood was taken from a skin incision. The case was nonfatal
and occurred late in the fall.
Fig. 5. Red corpuscles from the blood of an acute, fatal case, 20 hours
before death. The Texas-fever microbes _a_ are shown as pear-shaped bodi
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