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Warts (papillomatosis) in Cattle
Randall
J. Berrier, DVM
Staff Veterinarian
Technical Service
Papillomaviruses are the cause of
cutaneous warts in cattle and horses. These viruses have
considerable host specificity.
In cattle, warts can occur on almost any
part of the body. These warts are often morphologically
specific, caused by distinct papillomaviruses, so that
immunity to one of them does not necessarily confer immunity
to others.
The method of spread is by direct contact
with infected animals, infection gaining entry through skin
abrasions. It is
a disease mostly of young animals.
Immunity after a natural attack persists for at least
two years.
Warts ordinarily cause little harm and
usually disappear spontaneously in 6 to18 months. In purebred
cattle, warts may interfere with sales because of their
unsightly appearance.In extreme cases cattle with extensive
cutaneous wart lesions may lose condition and develop
secondary bacterial infections.
Warts on teats of dairy cows often cause interference
with milking. Warts
on the teats do show an increasing frequency with age.
Clinically there is little difficulty in
making a diagnosis of papillomatosis with the possible
exception of atypical papillomas of cattle.
These tumors persist for long periods and are discrete,
low, flat and circular in appearance.
If cattle have been vaccinated with the commercial wart
vaccine and this type of wart occurs - it may be an atypical
papilloma.
Surgery and vaccination, or a combination
of both, are the most common forms of treatment and
prevention. The
vaccine for cattle may be a commercial vaccine (Colorado Serum
Company Wart Vaccine), or an autogenous vaccine.
It is beneficial to use many types of tissue from
different sources in the vaccine - which Colorado Serum
Company does with their commercial wart vaccine.
This allows the vaccine to potentially provide more
"broad spectrum" protection against a variety of
papillomavirus isolates in the field.
Two injections of vaccine 3 - 5 weeks
apart are recommended.
Surgical removal is sometimes necessary
and removal of one or two warts in cattle has been recommended
to encourage the rapid disappearance of the remainder.
(This does not work in horses.)
Vaccination of cattle with Colorado Serum
Company's Wart Vaccine is an effective prevention.
An autogenous vaccine prepared for a specific problem
in a small community may have an advantage if they have a
unique local isolate. |