they attached themselves to the skin they inoculated the cattle, and Texas
fever would break out a week or more thereafter. For many years there had
been a growing suspicion that the cattle tick was in some way concerned in
the spread of Texas fever, and the facts which supported this supposition
finally became so numerous and convincing that a series of experiments was
inaugurated by the Bureau of Animal Industry which served to show that the
tick is abundantly able to carry the disease to a herd of healthy cattle,
and, in fact, is probably the only agent concerned in the transmission of
the disease from southern cattle to susceptible northern animals.
_Injurious effects of cattle ticks._--Unfortunately many cattle owners who
have always been accustomed to see both ticks and ticky cattle on their
farms are not inclined to attach much importance to these parasites, and,
as a rule, through lack of appreciation of their damaging effects, placidly
consider them as of little consequence. That ticks may be detrimental to
their hosts in several ways has probably not suggested itself to these
stockmen, who are most vitally affected, and it therefore seems necessary
to emphasize the fact that, in addition to their relation to Texas fever,
they may also be injurious to cattle as external parasites. While the power
of transmitting Texas fever is undoubtedly the most dangerous property
possessed by the cattle tick and is the principal cause for adopting
stringent measures looking to its complete eradication, nevertheless there
still remain other good reasons for the accomplishment of this achievement.
These secondary objections to the presence of ticks on cattle consists in
the physical harm they do to the host aside from the production of the
specific disease of Texas fever. True, a few parasites may remain on cattle
indefinitely without causing any noticeable effect, but it is not uncommon
to notice bovine animals on pastures with their hides heavily infested with
these pests. In such cases it can readily be seen that the continuous
sucking of blood causes more or less impoverishment of the circulation. The
animal must therefore be fed more in order to meet the demands of the
parasites in addition to the ordinary needs of the host. If the ticks are
removed from the body, the bites inflicted are often distinguished by
small, inflamed or reddened areas somewhat swollen, with perforations of
the skin which may allow the entrance of
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