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To obtain accurate and
confident results from
laboratory tests,
sampling method and
sample submission to
laboratory is very
important. By
considering these
reasons we request from
all Pasteur laboratory
clients, for sampling
and sample submission,
to use these guidelines:
Poultry and Caged Birds
In most cases a flock
problem is already being
investigated. Please
supply a good clinical
history to include age,
morbidity and mortality
patterns, information on
medication and
vaccination policy and
the type of husbandry
system.
1. A batch of birds
(e.g. 6 to 10) should be
submitted for
post-mortem, dead and
live moribund birds
should be submitted as
appropriate.
2. Individual birds may
be all that is available
from small flocks.
3. Serology can often be
a useful diagnostic tool
in flock problems.
4. Fresh carcasses
should be submitted as
post-mortem autolysis
occurs rapidly
particularly with
chicks. Carcasses should
not be frozen as this
leads to tissue
deterioration and
renders histology
useless.
5. Parasitic infections
caused by motile
protozoa (Hexamita,
Trichomonas,
Spironucleus/Hexamita
etc) are particularly
prevalent in game birds.
It is essential that
live birds are submitted
for an accurate
diagnosis to be made.
Please consult the
Pasteur laboratory
veterinarian before
sample submission.
Psittacines
For safety
reasons post-mortems
should only be carried
out in a microbiological
safety cabinet. If
sending carcasses
through the post, please
ensure they are
double-wrapped in
plastic bags before
being boxed. On the
outside bag apply an
obvious note
‘Suspect Psittacosis’ so
that our staff are not
accidentally exposed to
infection whilst
unwrapping the post.
1. All psittacines are
treated as potentially
infected with
psittacosis and will be
routinely screened for
this condition. If you
wish to screen live
birds, pooled faeces
from an aviary or
individual bird samples
can be tested by the
PCR.
2. Send fresh
unpreserved faeces or
cloacae swabs but do not
use swabs with wooden
shafts.
3. If a negative result
is found then a repeat
sample 7-10 days later
gives greater assurance
of freedom from
infection.
Please consult the
Pasteur laboratory
before sample
submission.
Microbiology Sampling
Methods
A- Sampling for
Aerobic Bacteriology
1. Samples should be as
fresh as possible.
2. Sear the surface of
organs with a flame or
heated scalpel blade
prior to swabbing.
3. Submit swabs in
suitable (sterile
isotonic) transport
medium.
4. Faeces samples (not
just swabs) are
essential if tests other
than basic bacteriology
are required.
5. Fastidious organisms
such as mycoplasma,
campylobacter and
leptospira require
special attention.
Please contact us to
discuss sampling
arrangements.
6. Most bacteria will
grow on culture medium
after 24 hours
incubation and
antibiotic sensitivity
will entail a further 24
hours.
Some exceptions are:
a. Salmonella by
enrichment - minimum 3
days
b. Campylobacter - up to
5 days
c. Brucella abortus -
minimum of 4 days
d. Mycobacterium
paratuberculosis (avian)
spp - 6 to 12 weeks
e. Mycoplasma - 10 days
to 4 weeks
f. Dermatophytes - 3
weeks.
Microbiology (continued
B- Sampling for
Anaerobic Bacteriology
1. For swabs use
anaerobe transport
medium.
2. For fluids fill the
container to very top to
exclude any air.
3. Wrap tissues tightly
in polythene to exclude
any air.
4. For clostridial
enterotoxaemia
diagnosis, send a
minimum of 2 ml of small
intestinal contents
collected from at least
three sites in the
ileum. Do not use any
preservative. (Note:
Clostridial toxins
cannot be detected in
kidney.)
5. For clostridial
myositis or black
disease in cattle, or,
take four impression
smears from the cut
surface of affected
muscle or liver, air-dry
and send in slide box or
submit tissue specimen
in a sealed air tight
container.
C- Mastitis
Examinations
Contaminated milk
samples will give
misleading results. To
avoid contamination use
the following collection
method:
1. Brush loose dirt,
bedding and hair from
teat. Grossly dirty
teats should be washed
and dried thoroughly.
2. Discard first streams
of milk from the teat.
3. Pre-dip using an
effective pre-dip
product allowing 30
seconds contact time.
4. Dry teat thoroughly
with a paper towel.
5. Scrub the teat end
with cotton wool
moistened with 70%
alcohol. Use as many
cotton wool pieces as
necessary to clean the
teat end, the last piece
should be spotless.
6. Allow the teat to
dry.
7. Remove the cap of a
sterile sampling tube
and hold it facing
downwards. When
collecting the milk
sample, hold the tube at
approximately at 45°
angle. Do not allow the
lip of the tube to touch
the teat. Collect 1-3
streams of milk and
immediately replace the
cap.
Please consult the
Pasteur laboratory
veterinarian before
sample submission.
Parasitology
1. Faeces:
Submit at least 10g
faeces in a
wide-mouthed,
screw-capped container
(50g for lungworm
larvae).
2. Blood: For blood
parasites send 2 ml
whole blood in EDTA tube
or two thinly spread
films fixed in methanol.
3. Skin: For skin
parasites send deep
scrapings (draw blood)
and scabs with
hair/feathers for
mange/feather mites or
plucked underlying hair
for ringworm.
Send fresh, undamaged
specimens of ticks, lice
and fleas in
screw-capped containers.
All samples should be
submitted in screw-top
containers and not
envelopes.
Please consult the
Pasteur laboratory
veterinarian before
sample submission.
Serology Sampling
Paired sera are
valuable in the
diagnosis of respiratory
and other disease
outbreaks but please
note the following:
1. If the first sample
is taken too late the
animals may have already
seroconverted and the
outbreak may be over by
the time the second
sample is due.
2. Sample several
animals ensuring that
they are identified
properly for second
bloods to be taken.
3. Sampling intervals
can vary but as a
general rule, they
should not be less than
two weeks.
4. Antibody levels in
single samples are of
limited value since they
are difficult to
interpret.
Please consult the
Pasteur laboratory
veterinarian for further
advices.
Virology Sampling
ELISA test
permit rapid
identification of BVD/MD
in both live animals and
carcasses.
A- Live Animal selection
1. Select recently
affected animals.
2. Animals with
muco-purulent nasal
discharge are less
likely to yield virus.
3. Blood of affected
animal with disease
symptom or fever is a
good sample.
4. Blood of affected
animal with clinical
sign suspected to PI is
a good sample.
B- Carcasses
1. Submit intact fresh
carcasses or lung
tissue.
2. Two or three blocks
of lung tissue (2 cm
cubes) from the junction
between healthy and
affected tissue or
tracheal/bronchial
swabs.
3. Tissues or swabs
should be forwarded to
the RL as soon as
possible.
Isolation of viruses
from field cases is not
routinely undertaken, is
time-consuming and often
difficult as some
respiratory viruses
survive poorly in
transport. When virus
isolation is required
the samples should be
submitted in virus
transport medium (VTM).
Please consult the
Pasteur laboratory
veterinarian before
sample submission.
Cytology
1. Aspirated
fluid is best placed in
an EDTA container before
submission.
2. Direct smears should
be made in the same way
as blood smears then
air-dried and fixed in
methanol for a minimum
of 5 minutes.
3. Please submit 2-3
smears to allow for
different staining
methods.
Please consult the
Pasteur laboratory
before sample
submission.
Histology Sampling
1. Tissue
samples should not be
more than 1 cm thick.
2. Samples should be
fully representative of
the basic organ
structure and include
the junction between
gross lesions and normal
tissue.
3. Samples should be
immersed in 10-20x their
volume of fixative as
soon as possible.
4. Samples should be
sent in an appropriately
sized container with a
wide opening.
5. Brain is best fixed
whole allowing the
pathologist to select
appropriate sites.
6. Collect intestinal
samples, as soon after
death as possible
(minutes not hours),
from several sites of
small and large
intestine.
7. Immersion fixation of
gut tubes 1-2 cm in
length is satisfactory,
but avoids crushing with
forceps. Gentle
agitation of the sample
in the fixative will
help displace food
material.
If the above guidelines
are followed, primary
fixation of most samples
should take 24-48 hours.
However, whole brains
will take longer.
Please discuss with
Pasteur laboratory for
more information.
Packaging and Sending
Histological Samples
1. Material must be
properly packaged.
Packaging must conform
to the postal
regulations for
packaging of
pathological material.
2. Urgent cases can be
sent immediately if the
container is filled with
fixative so that primary
fixation occurs in
transit.
3. If no urgent, tissue
can be initially fixed
for 48 hours then sent
in a reduced volume of
fixative. This method is
particularly appropriate
for brain.
4. The recommended
fixative for most cases
is formalin 10%.
5. For formalin 10%
preparation, please mix
one part of commercial
formalin (for example
100 ml) with nine parts
of water (for example
900 ml).
Please consult the
Pasteur laboratory
before sample
submission.
Food Sampling for
Chemical Analysis
1. Submit
samples in closely tight
plastic or nylon
containers to prevent
any extra moisture and
lipid adsorbtion.
2. Several samples must
be submitted in
different containers.
3. Take samples from
different parts of a
batch, particularly if
you have a big batch.
Please consult the
Pasteur laboratory
before sample
submission.
Food Sampling for
Microbial Tests
1. Submit
samples at 0-4ºC to
laboratory (Use ice
packs if necessary)
2. Some samples such as
ice-cream must be
submitted as frozen.
3. If possible don’t
damage the original
package.
4. Use sterile
conditions (near the
flame) for separating
some parts of the
sample.
Please consult the
Pasteur laboratory
before sample
submission.
Water Sampling
1. Use sterile
containers for sampling.
Please contact Pasteur
laboratory for providing
sterile container.
2. If providing a sterile
container is impossible,
boil glass container
with metal lid for 20-30
minutes, and use it for
sampling.
3. Submit sample as soon
as possible (less than
24 hours).
4. For microbial
analysis, use ice packs
for sample submission.
5. The information about
sampling method, origin
of water (well, surface
water, etc.), sampler
and other information
must be submitted to
laboratory.
6. For microbial
analysis, disinfect
water tap or pipeline
with alcohol or flame,
and let water flow at
least for one minute,
then take sample in
sterile container.
Please consult the
Pasteur laboratory
before sample
submission.
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