Coccidiosis is an intestinal disease that is widely distributed among pigeons throughout the
world. Coccidia inhabit the small intestine of nearly all pigeons.
Pathogen:
Along with trichomonads, coccidia are the most commonly found protozoa in pigeons, occurring
in the form of two eimeria species: E.labbeana and E.columbarum. Both species only infest
pigeons. Coccidia form permanent stages (oocysts), which only become infective after maturing
in the environment.
Course of disease:
Following ingestion of the oocysts, their subsequent developmental stages damage the intestinal
wall. Within 4-7 days of infection, the pigeon starts to excrete oocysts again.
There are two forms of coccidiosis:
The asymptomatic (or subclinical) form occurs most frequently. After ingesting small quantities
of oocysts for the first time, pigeons develop an immunity to infection due to stimulation of
endogenous defence mechanisms, without visibly succumbing to the disease. With this
protection, which is reinforced by constant ingestion of low levels of oocysts, the birds live in
a kind of equilibrium with the parasites, which also protects them against severe intestinal
disease.
The visible form of the disease with an acute course and severe generalised disturbance -
true coccidiosis - occurs when still unprotected young pigeons become infected by ingesting
large amounts of oocysts or when the immunity of older pigeons is reduced or broken down by
stress factors.
Symptoms of the disease:
Asymptomatic form:
Infested birds appear healthy, albeit rather less lively. The droppings are sometimes rather
soft.
Acute course:
Visibly affected pigeons produce malodorous, muco-aqueous, greenish and sometimes bloody
diarrhoea. They are listless, have puffed-up plumage and drink profusely, with reduced feed
intake.
Recognition of the disease:
Coccidial oocysts can be demonstrated by microscopic examination of faecal samples (prepared
according to the flotation method).
Asymptomatic form:
Only a small quantity of oocysts is identified in the faeces (finding = +).
Acute form:
The contents of the gut reveal moderate (finding = ++) or severe (finding = +++) oocyst
infestation.
Similar conditions:
Salmonellosis, E.coli infection, worm infestation.
| Coccidiosis |
