WEBVTT

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(English captions by Andrea Matsumoto, University of Michigan.)

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These are the items we require in the stool
concentration technique.

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We need the stool sample, the fine mesh of
pore size three fifty to four fifteen micrometer,

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the fifteen mL centrifuge tube, a glass applicator
for emulsifying the stool sample, the beaker

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for the filtrates, the ten percent Formol-saline
for mixing the stool, then the diethyl ether.

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Add ten percent Formol-saline to the stool,
about a gram of the stool sample.

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Emulsify the stool sample with the applicator.

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Emulsify it very well to get a smooth substance.

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Sift the stool sample through the fine mesh
into the beaker.

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Discard the stool sample.

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The debris is discarded under the tap water
because it has been disinfected already with

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the Formol.

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Transfer seven mils of stool filtrate into
the fifteen mil centrifuge tube.

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Rinse whatever is left in the beaker into
the centrifuge tube.

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Add three mils of the diethyl ether to the
seven mil of the stool filtrate in the fifteen

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mil centrifuge tube making it to a total of
ten mL.

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And we will see two layers: the ether layer
and then the Formol-saline layer.

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Cover the centrifuge tube with a lid and mix
the two layers very well.

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And thus the ether is to dissolve in the fat,
which is present in the stool sample, to release

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the parasites.

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Put it in the centrifuge tube balancing it.

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Centrifuge at thousand five hundred (1500) RPM for
two to five minutes.

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Okay take out the centrifuge tube and you
will see four layers.

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The first layer is the ether layer, the debris
layer, which is the insoluble pad, and then

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Formol-saline layer, and then the sediment
which contains the parasite.

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Break through the debris layer and discard
the first three layers under the tap water,

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which have already been treated with Formol.

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So the sediment will contain the parasites
of the egg or the larvae and then cysts were

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suspended with part of the Formol-saline or
saline.

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Use a disposable pipet to transmit it very
well and transfer a drop onto the microscope

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slide.

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Cover the drop of smear with the cover slip
and examine it under the microscope using

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the times ten objective (10X).

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Low light allows better to see the parasite
of the egg, the cyst, and the larvae.