lab pro - weel 2-4 pre-lab quizzes

which fecal analysis method uses water instead of flotation solution?

fecal sedimentation

You attempt to calibrate a microscope using a ruler. At the 4X objective lens, you measure 4.5mm across in diameter. To convert this diameter from mm to um, you will _________ by 1000

multiply

What piece of equipment is placed in a fecal flotation solution to measure its specific gravity?

hydrometer

three common flotation solutions used:

1. zinc sulfate,

2. sodium nitrate

3. sugar solution

What is included in the gross examination of a fecal sample?

• consistency

• color

• presence of blood

• mucus

• odor

• adult parasites

• foreign bodies

how do you measure the ova being examined if it is oval shape?

note its length and width

fecal flotation solutions have a lower specific gravity than common ova resulting in ova floating to the surface

false

which method may use a Fecalyzer or pill vial to complete a fecal floatation procedure?

simple fecal floatation

For the Centrifugal Flotation method, once the sample is centrifuged, a pipette is used to take 1-2 drops of sample from the:

top of the solution because the ova float to the top after centrifugation

The centrifuge must be balanced before use, either with a water-filled balance tube or a partner’s tube of equal volume.

true

which method is best for suspected ova that are large or heavy?

fecal sedimentation

What method of fecal analysis is used:

1. Place 1–2 drops of saline on a microscope slide.

2. Using a tongue depressor, mix a small amount of fresh feces into the saline to create a thin, even layer.

3. Add a coverslip.

4. (Optional) Apply an appropriate stain to the edge of the coverslip to enhance visibility of the slide contents.

Direct smear

What best describes a Tricuris vulpis egg?

oval shaped with bipolar plugs

what stains may be used in lab when preparing a direct smear?

methylene blue or Lugol’s iodine

what is the preferred method of fecal analysis due to the fact it yields more ova?

centrifugal floatation

Toxocara canis, T. cati, and T. leonina are examples of:

Nematode, roundworms

Feces, soil, or animal tissue may be used to recover larvae from the Baermann apparatus.

True

fecal samples may have zoonotic potential and must be handled carefully

True

Warm fecal floatation solution is poured on sample in Baermann apparatus

False; warm water is used

only whole blood or serum may be used for the Heartworm Antigen Test

false

what is the correct method for examining egg packets from a proglottid segment under a microscope?

place proglottid segment on a slide with drop of saline, break it open with tongue depressor, add cover slip, examine 

What does a positive Heartworm Antigen Test look like?

two lines at the “C” and “T” positions

why must a control line be present on the Heartworm Antigen Test?

to ensure quality assurance and validity of the test

what is intermediate host of Dirofilaria immitis?

female mosquito

what does an invalid Heartworm Antigen test look like?

one line in the “T” position

how many m is a parasite ova that measures 563um?

0.000563 m