TRICHOMONIASIS
Information
from Cornell Laboratory of Ornithology
Link to this website is included
below
Trichomoniasis is a
disease that most commonly affects pigeons, doves,
and the raptors that feed on them. It is
characterized by raised lesions in the mouth,
esophagus, and crop. Infected birds may appear to
have trouble closing their mouth. The disease is
caused by the protozoan Trichomonas
gallinae, which is often present in the mouth
secretions of birds that appear to be healthy but
are carriers of the disease, such as pigeons.
Infected birds can
contaminate water containers (bird baths) with
their oral secretions, which can, in turn, expose
many other birds to the disease. Mortality from
this disease varies, but it can be quite high.
According to the
Cornell Laboratory of Ornithology, the general
consensus is that the disease is often spread
through fecal contamination of food or direct
contact. The likelihood of consuming contaminated
food or coming into direct contact with infected
birds is increased near concentrated food sources.
Feeders are the ultimate in concentrated food
sources. So, Cornell Laboratory of Ornithology
believes that it is always a good idea to keep
feeders and feeding areas clean in order to promote
a safe feeding environment.
Information
from the National Wildlife Health Center
Link to this website is included
below
Synonyms
Canker (doves and pigeons), frounce (raptors),
avian trichomoniasis
Cause:
Avian trichomoniasis is caused by a single celled
protozoan, Trichomonas gallinae. Avirulent
T. gallinae strains that do not cause
disease and highly virulent strains are both found
in nature and circulate within bird populations.
The factors that make a strain virulent are not
known, but they are thought to be controlled
genetically within the parasite. Similarly, the
reasons why an avirulent or a virulent form of the
parasite is found within a bird population at any
period of time also remain unknown. Virulent
strains of T. gallinae have caused major
mortality events or epizootics in doves and pigeons
in addition to less visible, chronic losses.
Infection typically involves the upper digestive
tract of doves and pigeons, but other species have
also been infected. Trichomoniasis in doves and
pigeons, but not in other species, is generally
confined to young birds. The parasite was
introduced to the U.S. with the introduction of
pigeons and doves brought by European settlers. It
has been reported that 80 to 90 percent of adult
pigeons are infected, but they show no clinical
signs of disease. It is speculated that most of
these birds became immune as a result of exposure
to avirulent strains of the parasite or because
they survived mild infections. In pigeons and
mourning doves, the parasites are transmitted from
the adults to the squabs in the pigeon milk
produced in the crop of the adult. Squabs usually
become infected with the first feeding of pigeon
milk.
Species
Affected
Trichomoniasis is considered by many avian disease
specialists to be the most important disease of
mourning doves in North America. Band-tailed
pigeons have also suffered large-scale losses from
trichomoniasis. This disease has been reported as a
cause of mortality in birds of prey for hundreds of
years prior to the causative organism being
identified. Songbirds are less commonly reported to
be infected, but T. gallinae is reported to
be the most important trichomonad of caged birds;
it is often responsible for epizootics among
captive collections. Domestic turkeys and chickens
also become infected.
Websites
for More Information
http://www.birds.cornell.edu/pfw/AboutBirdsandFeeding/DiseasedBirds.htm
Cornell Laboratory of Ornithology's information.
This site includes information on other diseases in
addition to Trichomoniasis.
http://www.nwhc.usgs.gov/pub_metadata/field_manual/chapter_25.pdf
Information from the National Wildlife Health
Center. This site includes graphs that may help
explain the incidence of trichomoniasis in
songbirds.
http://www.michigan.gov/dnr/1%2C1607%2C7-153-10370_12150_12220-27288--%2C00.html
Information from the Michigan Department of Natural
Resources. Includes information on transmission of
the disease, pathology, diagnosis, control, and
significance.
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex4444/$file/663-34.pdf?OpenElement
Information from Alberta's Agri-Facts. This file is
in a pdf format which can be printed.
WBFI
- 1305 N. Tahoe Trail - Sioux Falls, SD 57110 -
Phone: 888-839-1237 - Fax: 605-275-6697 - E-mail:
info@wbfi.org
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