1. Control of any predisposing stress factors. Dr Colin Walker, of the These can take the form of: Knox Bird Veterinary Clinic Australian Pigeon Company
(a) Environmental triggers, e.g. dampness, overcrowding, low
& Aussie Bird Vet Pty Ltd.
(b) Management triggers, e.g. poor feeding, excessive tossing, or
(c) Concurrent disease, in particular parasitism. This includes wet
canker. The combination of either worms or elevated
trichomonad levels and respiratory disease is very common.
The fancier must establish a healthy loft environment, otherwiserespiratory disease will continually recur, despite medication.
If you ask any experienced flier what health problem he fears the
2. Correct use of appropriate drugs to either
most, then if it is the breeding season he will probably say canker,
eradicate or keep the organism level low
but if it is the race season he will probably say respiratory
so that disease does not occur.
infection. Respiratory diseases are very common in pigeons. They
The organisms that infect the respiratory system and how
are the major cause of poor performance and pigeon loss during
they are controlled are set out below.
the race season. Young birds under stress are most at risk ofcontracting respiratory diseases, although healthy old birds can
CHLAMYDIA
fall ill when exposed to respiratory diseases in the race basket. Race birds with respiratory infection can be difficult to detect and
Chlamydia is a microorganism that is found within the system of
yet, like a human athlete with flu, cannot compete. When some
many pigeons all the time. There are many strains, which vary
fanciers talk about respiratory infection, they give the impression
tremendously in their capacity to cause disease. Lofts tend to have
that they are discussing a single problem and, yet, several
resident strains to which those birds, often through their on-going
organisms can be involved and often simultaneously. Clinical
exposure, have developed an immunity. In such lofts, it is only when
respiratory infection in pigeons is the end result of the interplay of
the birds are stressed that the Chlamydia is able to flare up and
a number of factors but, in particular, the type of infective
cause disease. It is through contact with other birds (strays, in race
organism and the vulnerability of the birds to infection are
units, new introductions) that new and potentially nastier strains gain
important . The respiratory system can be infected by Chlamydia,
entry to the loft. Control of Chlamydia is, therefore, double-barrelled
Mycoplasma, bacteria (in particular E. coli), fungi, viruses and
and involves the control of stress to avoid resident Chlamydia strains
mites. The control of some of these starts, in certain lofts, not only
flaring up together with the correct use of medication and the
before racing and not even during breeding, but right before the
prevention of new chlamydial strains entering the loft. Control of stress to avoid chlamydial strains,
Stress is always a big factor. The vulnerability of the pigeon is
already in the loft, flaring up
affected by what stress it is under. Stress weakens the bird,
A subsequent chapter deals with what constitutes stress and how
enabling infective organisms to cause clinical disease. The control
to avoid it, but essentially this involves on-going good care with
of respiratory disease is therefore two-pronged.
good management practices, a good loft environment and controlof other diseases, notably the parasitic diseases. Any problem thatweakens the birds makes them vulnerable to a chlamydial flare-
up. Sometimes, however, despite the best possible care, because
Because of the disruption to normal bowel bacteria caused by the
the strain of Chlamydia in the loft is virulent or the family of
antibiotics, which can compromise feather quality and check
pigeons is particularly vulnerable (as with some European strains),
development, and also because of the interference with
it becomes necessary to medicate the birds through stressful times
development of a natural immunity, it is important that only the
to prevent chlamydial flare-ups and the resultant clinical disease.
birds that need medication should receive it. If only a small
The particular times when these flare-ups are more likely to occur
number are affected, they may be treated individually with
are during breeding, after weaning and during the racing season.
doxycycline (Vibravet 50 mg, 1/2 tablet once daily) or Baytril (3drops twice daily). Once on medication, they stop shedding the
Breeding
organism and so there is no need to isolate them. If one bird has
Stress for a stock bird is breeding. Stressed stock birds will shed the
become unwell while the others are okay, it is often a reflection
organisms in their droppings, saliva and eggs. If the Chlamydia is in the
on its vigour. If such a bird fails to respond quickly or relapses, it
egg, the developing embryo is weakened and can either die during
is unlikely to go on and make a competitive race bird and is often
incubation, during the hatching process or as a nestling or, if it survives,
best eliminated. If more than 5-10% of young birds are affected,
be a retarded youngster. In a nestbox heavily contaminated with
with fresh cases daily, then all should be treated. Usually
Chlamydia, the developing youngsters become weakened and die. If
doxycycline 12% (1/2 teaspoon per litre for 3-5 days) is used.
these things have happened in earlier years, and breeding has
However, such a situation represents a major flaw in the birds'
commenced, it is too late to treat the stock birds. However, medication
environment or management and the longer-term solution is not
(usually doxycycline) can be given before mating to decrease the level
going to be drugs but identification and correction of the underlying
of Chlamydia in the stock birds' system. This means that they will then
cause. In young birds, this is often overcrowding. A faecal
require more stress before they start to shed the organism.
examination and a crop flush are a good idea to check for any
The length of treatment depends on the need, usually 7 - 30 days. If
concurrent disease in addition to reviewing other loft factors.
your loft has a history of chlamydial problems during breeding, a
After 1 March in Australia, as the youngsters get older, fanciers
prebreeding doxycycline course is a good idea. Chlamydia can be
look for signs of poor loft flying, excessive panting after training,
completely cleared with a 30-45 day course of doxycycline. However,
and sneezing within the loft. Even in the most healthy lofts, there
this is rarely done because the weaned youngsters will be exposed
can be occasional outbreaks of respiratory diseases. It is important
to the organism later in life and may in fact be more vulnerable to
to recognize that more than three sneezes within 5 minutes is a
illness through this lack of exposure and the resultant low level of
significant indicator of early respiratory disease. One would expect
natural immunity. Doxycycline, like other antibiotics, causes disruption
two to three sneezing outbreaks between January and May, even
of the normal bowel bacteria, interfering with vitamin metabolism
in the best managed loft. If there is doubt as to whether a
and calcium absorption. It is therefore important that preventative
sneezing outbreak is due to chlamydial respiratory infection, a test
courses are completed several weeks before pairing and there is
called a chlamydial antigen test can be done on the droppings by
benefit in giving the birds probiotics, vitamins and calcium
an avian veterinarian. Medication is used during this time as it is
from 1 December to 1 March. However, provided the birds are
After Weaning
well, medication is best avoided. With on-going good care, thebirds are likely to fix themselves and the level of natural immunity
The next vulnerable time is the postweaning period, when both
they form as a result will be much higher.
weaning and moulting are the underlying stresses. In Victoria,Australia, January to May are the respiratory months. Most lofts
DURING THE RACING SEASON
contain large numbers of young birds having just had the stress of
Exposure to new strains of respiratory infection
weaning and now having the stress of moulting, coupled withyoung bird tossing and racing. It is a time of high humidity and
All lofts are continually being exposed to respiratory infection
fluctuating temperature, conditions that favour respiratory disease.
through the race unit. In the race unit, many different birds from
Between 1 December and 1 March (the usual time that the last
many different lofts mix intimately in a warm humid environment,
youngsters are weaned in many lofts in Australia), fanciers must
which is ideal for the transfer of disease. In addition, the
monitor the youngsters, in particular, for signs of ‘one-eye cold’, dirty
confinement, different feeding patterns and time away from the
wattles or sneezing. However, green watery droppings, failure to
loft stress the birds. As a result, the Chlamydia levels can rise to
thrive, shortness of breath and a reluctance to fly may also be
If respiratory symptoms are noted, all birds are treated with
Prevention of new chlamydial strains
antibiotics (eg Doxy-T, Resfite) for 3-5 days. It is important to treat
entering the loft
these outbreaks early before they change into the serious form of
New strains enter the loft through exposure to other birds. Stray
respiratory, which can involve, and permanently damage, the air
youngsters and youngsters bought at squeaker sales are always
sacs, thus seriously compromising race performance.
high risk because, due to their age and the stress they are under,
Stress-induced flare-ups of resident strains
they are likely to be shedding chlamydial organisms they are
As mature race birds, it is racing itself that provides the stress,
carrying. Strays should be removed immediately and birds introduced
testing the level of immunity formed by the birds. In a well managed
deliberately only from reliable sources. By far the main means of
loft where drugs have been used correctly, this immunity should be
exposure is through the race unit. One stray is one exposure. Ten
relatively solid by the start of the season. Racing puts this immunity
birds going to a race and each sharing a drinker with ten other
to the test. In race birds, signs of Chlamydia flare-ups are
birds is 100 exposures (i.e. like getting 100 strays in one day). In
considerably more subtle. The birds are older, their natural immunity
some situations and, in particular within certain clubs and areas of
is higher and their response to disease is different. The signs
Australia, it becomes necessary to medicate returning race birds to
observed have been modified by these factors. Birds with respiratory
guard against infection picked up in the race unit.
infection have lost their zest for life and this is reflected in their race
Management
results. However, many things can lead to disappointing results and,
It can be seen that the appropriate management regime for
as antibiotics have the potential to make a race team worse, I, like
Chlamydia , including use of medications, varies from loft to loft
most fanciers, have to be convinced that respiratory infection is
depending on each loft's earlier problems and particular loft-
present and that their use is warranted. Birds that are reluctant to
based factors. An example is what I do with my own birds. My
fly, quiet in the loft and with dry feathers (no bloom) are suggestive
own loft is based on an established Australian long-distance
of respiratory infection. Sneezing (more than three times in 5
strain. Chlamydia is not a big problem. I do not medicate my stock
minutes from 100 birds), scratching at the nose, yawning, and
birds before pairing because I do not have chlamydial problems
wiping the nose on the wing butt all indicate irritation of the upper
during breeding. If I did, however, I would treat for 7-21 days
airways. On opening the beak, the tonsils may be inflamed, a thick
before mating as the need dictated. I get three to four youngsters
white mucus may be extending into the throat from the windpipe
per year with eye colds and these are individually treated with
or from the slit in the roof of the mouth, which may be closed due
Baytril (3 drops twice daily). To date, these have responded
to swollen edges, the top of the windpipe may be red and inflamed,
promptly. My race loft is very enclosed, which gives me good
the beak at the nostril opening may be wet, the cere may be slightly
control over the loft environment and enables me keep it as close
discoloured or there may be a slightly mucous component to the
to ideal as possible. Draughts, temperature extremes and high
birds' grunt while the gums or the muscles may be bluish.
humidity can be avoided. I would like to think that I care for my
Chronically infected birds show delayed recovery after a race and
birds well. Under my system of management during racing and
will develop green droppings after stress because of damage to the
with my loft environment, the resident chlamydial strains do not
liver. Testing of the droppings usually confirms the diagnosis.
flare up during the race season and so I do not treat preventively
If the loft has not had respiratory problems in previous years, I feel it
before racing. I do, however, have intermittent flare-ups of wet
is best to try and avoid antibiotic medication but monitor the birds
canker and the birds are regularly checked and treated through
closely and treat for 3-4 days if respiratory infection occurs. If respiratory
racing for this. I feel that with inadequate control of this, because
infection during racing has been a problem in earlier years,preventative
of the trichomonads parasitic, i.e. weakening, effect, it is likely that
courses of antibiotics can be given before racing in the same way that
the Chlamydia would also become a problem. I check my birds
they are given to stock birds to decrease the level of Chlamydia in the
droppings once or twice weekly and the birds are monitored
birds’ system so that they are less likely to break down with the stress
closely for signs of respiratory infection. If a respiratory infection
of racing ahead. Depending on the severity of the problem in earlier
became established, the birds would be given a 3-5-day antibiotic
years, these courses are usually 7-20 days in length. In such lofts,
course. My returning race birds are not treated for respiratory
follow-up periods of medication may be necessary during the season,
infection because, to date, this has not been a problem. However,
and a common recommendation is 3 days treatment every third week,
if it was a problem, I would treat them.
with Monday,Tuesday and Wednesday usually being the days to treatsuch a resident problem. After antibiotic use during racing, the birdsshould always be given a day on either probiotics or multivitamins. MYCOPLASMA Management
Mycoplasma is a problem of the race season. It is what is called a
What should the fancier do if the problem is diagnosed?
primary erosive disease. Many vets agree that Mycoplasma by
• A health profile, i.e. examination of the saliva and droppings, to
themselves do not cause disease and, in fact, in experiments in
assess any concurrent disease that may need treatment and
which healthy pigeons have been deliberately infected, the birds
general on-going good care to ensure a good response to
have not become sick. However, the organisms do superficial injury
to the lining of the respiratory system, enabling secondary
• A gradual return to exercise. Always with respiratory infection
organisms, notably Chlamydia, bacteria (such as E. coli) and fungi
there is an extended convalescence of usually 1 - 3 weeks. The
(such as Aspergillus), to become established. In this way,
birds must be given time to recover their fitness once
Mycoplasma, although not directly affecting health, has a big effect
medication has cleared the infection. They should not be forced
on race performance. Failure to control the problem in an affected
to fly around the loft and once it is apparent that their vigour for
team renders all attempts at success hopeless. Some Dutch vets
flying has returned, initially short tosses only should be given
state that as many as 90% of teams are affected and teams are
(less than 1/2 hour). Observe the birds closely for signs of
presumed to be affected unless they have been recently treated.
breathlessness on landing from these tosses and only when they
Pigeons harbouring Mycoplasma organisms cannot achieve
are handling these well should longer tosses be given. When
superhealth and are prevented from achieving top racing results.
managing tosses of 1-1 1/2 hours well, it is usually safe to
Mycoplasma are primary pathogens of the respiratory system and
resume racing. In well-managed lofts with no other health
the signs displayed by the birds depend on the part of the
problems, response to treatment can, however, be dramatic and
respiratory system affected. In the throat, nose and windpipe,
I have had an interesting experience where two flyers both
signs are similar to those described for Chlamydia earlier.
diagnosed with Mycoplasma in their teams succeeded in
However, Mycoplasma notably causes inflammatory changes in
gaining 1st and 2nd Federation (3000 birds) in an all-day 500-
the top 20-30% of the windpipe, causing mucus to accumulate
there and birds that have a broken grunt or sound mucousy in the
• Good food, good care and an appropriate multivitamin
upper airway always make me think of Mycoplasma. Where the
airsacs are affected, the birds cannot properly breathe and so evenmoderate exercise is tiring and sometimes forces the birds to land
• Medication. The choice of drug is sometimes dependent on the
on the nearest available surface, which may be a tree or building
involvement of secondary organisms such as Chlamydia and E.
near the loft. Because of the difficulty in breathing, the gums and
coli. Baytril can be used with care during racing. Other
muscles can turn blue and because of the inability to exercise,
antibiotics such as doxycyline, Tiamulin or Tylan are effective.
muscle tone and race fitness cannot come. The airsacs regulate
However, the current recommendation is that doxycycline and
fluid within the body by controlling evaporation of moisture from
Tylan combined be given. An initial course of usually 5-10 days
their surfaces. When diseased, excessive moisture is lost and the
is given depending on the severity of the infection with several
birds, therefore, need to drink more even after moderate exercise,
follow-up courses, usually 2-3 days every 2-3 weeks until one is
or run the risk of dehydration. Often, however, signs are very
sure that the birds are well. The usual preparation used in
subtle and may simply be deteriorating performances.
Australia is Doxy-T which contains doxycycline and Tylan.
Like Chlamydia, Mycoplasma are more likely to cause disease
In some Federations in Australia, there is significant risk of picking
when the birds are stressed. Most lofts do have resident
up nasty Mycoplasma strains in the race basket. In these areas and
Mycoplasma strains and new Mycoplasma strains can enter the
Federations, antibiotic combination medication is given
loft through contact with other birds. Mycoplasma is a difficult
throughout the season to control the problem, usually for 2-3 days
disease to diagnose in the live bird. Only certain labs culture
every 2-3 weeks depending on the severity of the problem and the
Mycoplasma, which is an expensive procedure. Blood tests are
used to diagnose the condition in chickens. There are changes at
Dr Colin Walker established the Australian Pigeon Company in
autopsy, both grossly and microscopically, that are suggestive.
1994, to develop, manufacture and distribute a range of
Changes are also found on faecal smears and crop flushes of
veterinary medicines and health supplements for pigeons. Dr
affected birds, which are discussed in other sections of this book.
Walker's veterinary expertise, together with his knowledge of the
A good response to a short treatment trial with Doxy-T (see
requirements of pigeon racers, gathered through experience of his
Medication Guide) also supports the diagnosis
own race team, place him in the unique situation to develop such
products. The result is a range of quality products made for thepigeon racer and based on sound veterinary knowledge.
A summary list of the most popular and widely used productsfollows, together with information on the common diseases andthe best way to use these medications in their control. The mostcommon health problems encountered in pigeons are canker,respiratory infection, Coccidia, worms and external parasites. The medications that are used to control these are: 1. Baycox Coccidiocide Solution:Toltrazuril-based, this effective
Coccidia medication requires only a 2-day treatment course;safe to use during all stages of the pigeon year. 2. Turbosole: The safe, effective, quick-acting treatment for canker.
The medication of choice during breeding, racing and moulting. 3. Doxy-T: A blend of Doxycycline and Tylan. Recommended by
veterinarians worldwide as the medication of choice to treatand manage the respiratory infection complex during racing. 4. Resfite: The antibiotic blend of choice for respiratory infection 5. Moxidectin: A clear water-soluble wormer that not only eliminates
roundworms and hairworms but also eradicates all externalparasites (including airsac mites) that feed off body fluid. Readily taken by the birds, there is no need to withhold food. The wormer of choice during racing, breeding and moulting. 6. Permethrin: A pyrethroid insecticidal spray that can not only
be used to spray or dip the birds but also to spray the loft. 7. Moxidectin Plus: A moxidectrin/praziquantel water-soluble
worming solution that also treats tape worms.
All of the medications listed in the article are available in the USAthrough Siegel's, their phone number is 1-800-437-4436.
Journal of Food Protection, Vol. 73, No. 2, 2010, Pages 376–379Copyright G, International Association for Food ProtectionAntibiotic Resistance in Salmonella Isolates from ImportedChicken Carcasses in Bhutan and from Pig Carcasses in VietnamL. ELLERBROEK,1* D. NARAPATI,2 N. PHU TAI,3 N. POOSARAN,4 R. PINTHONG,4 A. SIRIMALAISUWAN,4P. TSHERING,2 R. FRIES,5 K.-H. ZESSIN,5 M. BAUMANN,5 AND A. SCH
DORSET COUNTY ASA 2008 DORSET COUNTY MASTERS & SENIOR AGE GROUP CHAMPIONSHIPS All Clubs, coaches and competitors should carefully read the information given below before completion of entry forms. This sheet should be retained for future reference. General Conditions: 1. The current Dorset County ASA General Competition Conditions will apply as printed in the ASA SouthWe