various kinds of disease germs,
and showing that more or less irritation of the hide is produced by these
parasites. This condition, together with the loss of blood, frequently
induces an irritable state and evidence of uneasiness commonly known as
"tick worry," which results in the loss of energy and other derangements of
the animal's health. It may in some cases, especially in hot weather,
become so pronounced that the animal will lose flesh in spite of good
pasturing, thereby reducing the vitality and rendering it more susceptible
to the inroads of disease. Moreover, if the infestation of ticks is not
controlled, the cattle may be so reduced in condition that growth is
retarded, and, in the case of young animals, they may never become fully
developed, but remain thin, weak, and stunted--a condition that has been
termed "tick poverty"--and easily succumb to other diseases as a result of
lowered vitality. In milch cows this debilitating influence of the numerous
ticks is shown in a greatly reduced milk supply. This should not appear
strange when it is considered that some animals harbor several thousand of
the bloodsucking parasites. If these parasites are crushed, it will be
found that their intestines are completely filled with a dark, thick mass
of blood abstracted from the animal host and containing nutriment that
should go to the formation of milk, flesh, and the laying on of fat. In
some rare cases the large number of bites on a limited area of skin may be
followed by infection with pus-producing organisms, giving rise to small
abscesses which may terminate in ulcers. The discharge from these sores, or
in some cases the mere oozing of blood serum through the incision made by
the mouth parts of the ticks, keeps the hair moist and matted together, and
the laying and hatching of fly eggs in these areas give rise to infestation
with destructive maggots, causing ulcers and other complications that
require medical treatment. These statements regarding the secondary
injurious effects of cattle ticks also apply to those ticks which have been
previously spoken of as harmless so far as Texas fever is concerned, and,
in fact, to all external parasites. Therefore, it is just as important to
eradicate the cattle ticks for reasons other than those associated with
Texas fever as it is to exterminate lice, fleas, and other vermin.
Furthermore, cattle ticks, aside from the losses sustained by their purely
parasitic effects, are the
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