| Description:
|
Protozoan parasite,
Trichomonas gallinae, causes the disease trichomoniasis
in birds. It can infect pigeons, doves, turkeys, chickens,
quail, hawks, eagles, falcons, canaries, parrots, sparrows,
swallows, goldfinches and cardinals. The protozoan exists
in a trophozoite stage only and moves by means of hair-like
structures known as flagella. Baby pigeons or squabs
become infected when they ingest trophozoites in pigeon
milk produced in the crop. In pigeons, the disease is
called canker and they may be infected by ingesting
contaminated food or water. Raptors may become infected
by eating infected birds and in raptors, the disease
is often called frounce. Other types of birds may become
infected by ingesting the parasite in contaminated water.
Nestlings of many species may become infected with an
umbilical form which occurs when trophozoites pass from
an infected nestbox through the navel. The trichomonas
parasite lives in the mouth, esophagus, crop and tracheae,
but may also spread to other organs. Trichomonas gallinae
may cause white plaques and inflammation in the oral
cavity. An infected bird may have a loss of appetite,
vomiting, ruffled feathers, diarrhea, dysphagia (difficulty
in swallowing), dyspnea (difficulty in breathing), weight
loss, and increased thirst. Droppings may have a yellow
discoloration that is most commonly visible in the white
portion. Young birds are most frequently infected and
can die from the parasite. Some birds may be carriers
and show no sign of the disease. |
| Diagnosis: |
Diagnosis of trichomonas
may not be easy. The disease may resemble poxvirus,
candidiasis, or vitamin A deficiency. The parasite DNA
can be detected in oral fluids and in scrapings taken
from the crop or from oral lesions by PCR test. Positive
result confirms active infection. |
