Psittacosis, the "terror" of bird keepers,
has long been a menace to numerous species of birds
kept by cage and aviary bird keepers. Not only does
it pose a threat to birds in captivity, it can also
be transmitted to their owners, for whom the consequences
are not to be taken lightly.
A number of factors have in the past contributed to building up what seems to
be an aura of mystery and invulnerability around Psittacosis;
the ability of the disease to recur at different times
in both birds and humans, the difficulty often associated
with diagnosing the disease, and the ability of Psittacosis
to co-exist with other diseases. This has given the
impression that the disease is unbeatable, Veterinarians
at the Vetafarm Research Facility in Wagga Wagga, Australia,
however, have shown that Psittacosis can be defeated
when good bird management practices are combined with
the use of their product "Psittavet".
The following interview was taken with Vetafarm veterinarian Dr Tony Gestier;
Q What is Psittacosis and why is it a menace
to cage and aviary bird keepers?
A Psittacosis is a disease
caused by the bacteria Chlamydia psittaci which lives
and reproduces inside the living cells of birds and
humans. Not only does the bacteria cause death in birds,
it also lowers the resistance of their immune systems
to secondary infection. This, in effect, allows Psittacosis
to co-exist with other diseases. Psittacosis is one
of the most common infections in cage and aviary birds.
It can wreak havoc in aviaries, causing reduced fertility,
and fecundity, deaths in the nest and sporadic deaths
among breeding stock. The disease can also be transmitted
to humans who may suffer fever, uncontrollable shaking,
blinding headaches, a swollen spleen, muscle aches,
pains, and sometimes a cough. Unfortunately the body
cannot build up natural immunity to it, and unless correctly
treated, the disease can return when the body's natural
defences are low.
Q How is the disease transmitted?
A The Chlamydia bacterium
is transmitted in a number of ways. It can be transmitted
from one host to the next through direct contact between
hosts, by breathing in feather dust and dust from faecal
build-up, and through direct contact with other bodily
secretions from infected birds.
Q What are the symptoms of Psittacosis in birds?
A Because the Chlamydia bacterium
can exist in healthy birds for long periods of time
without causing disease, bird keepers may not notice
any problem with their birds until the birds are put
under some kind of stress, such as when young birds
are taken away from their parents. Stress has the effect
of lowering the strength of birds' immune systems, making
them more susceptible to disease. However, even when
Psittacosis manifests itself in birds, it is difficult
to diagnose due to the fact that it coexists with other
diseases. This means that a wide range of symptoms may
appear. Some of these may be going light, eye disease,
sudden deaths, infertility, diarrhoea and fluffed bird.
Q Are management practices important in
controlling the disease?
A Management practises are
crucial in controlling Psittacosis because treatments
such as Psittavet alone cannot defeat the disease. Any
practise that reduces stress on the birds such as maintaining
a healthy diet and preventing overcrowding in an aviary
will help prevent Psittacosis from taking hold. We recommend
that faecal build up be kept to a minimum and that birdkeepers
wear a dust mask, when working in dusty aviaries, for
their protection. Chlamydia can survive in the waste
and later be transmitted by dust particles. We also
recommend an extractor fan be fitted to closed bird
rooms at floor level. Not only does this take away feather
dust containing Chlamydia and other bacteria it also
pulls out colder air, thus maintaining a comfortable
temperature for birds and reducing stress.
Q How does Psittavet control Psittacosis?
A Psittavet is an antibiotic
that suppresses Chlamydia psittaci in the bird but will
not significantly harm the normal organisms that live
inside the digestive system, even with long term treatments.
It is administered by mixing with the birds' drinking
water, or the injectable form can be used in birds that
will not drink water.
Dr Gestier outlined a number of considerations
to be taken in treating birds with Psittavet.