| Description:
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Bordetella avium is
a small, gram-negative, non-fermentative, motile, strictly
aerobic bacillus responsible for the avian disease referred
to as bordetellosis. This bacterium was first isolated
from young turkeys in 1967 and officially named Bordetella
avium in 1984. Although it is an economically significant
disease in turkeys, B. avium has also been isolated
from cockatiels, Wagler’s conures, a Jenday conure,
a Muluccan cockatoo and a noble’s macaw. There
are further reports of B. avium being isolated from
numerous other species of birds including chickens,
finches, budgerigars, Japanese quail and ostriches.
In cockatiels, B. avium commences a path of infection
by colonizing the ciliated epithelium of the bird’s
tracheal mucosa. As the disease progresses, it will
destroy this outer layer of tissue along the respiratory
tract, and produce toxins that can affect other groups
of tissue in the body. In this respect, B. avium acts
similar to its human counterpart – Bordetella
pertussis (whooping cough) however, there is no evidence
that B. avium can infect humans. The bacterium is easily
transmitted by aerosols, leading to a rapid spread of
the disease in facilities where birds are housed closely
together.
Bordetellosis in psittacine birds manifests with upper
respiratory signs such as sneezing, nasal and ocular
discharge, swelling of the infraorbital sinus, and lockjaw.
Involvement of the lower airways is infrequent. Experimental
inoculation with B. avium in cockatiel chicks suggests
a 1-2 day incubation period. |
| Diagnosis: |
Diagnosis: Due to the difficulties experienced in isolating
and identifying B. avium, many believe that this disease
may be under-diagnosed. Because of evidence that suggests
recovered birds may periodically relapse or remain asymptomatic
carriers, the need for a sensitive and consistent diagnostic
test is significant. Recently, a PCR-based assay for
the detection of B. avium became available. This test
accurately detects the presence of B. avium in a sample
and can be used to identify asymptomatic carriers, as
well as confirm active infection in birds displaying
symptoms.
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