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Method

The counting technique we are trialling is simple, clean and has good sensitivity at even very light infections of 5-25 worms.

I'll make this description as verbose as I can so we are using the same technique. Then the only variation will be our different diets, time of day, drinking habits etc.

Add 1g of fresh Poo to a Fecalyzer

  1. Take your scales and a fecalyzer to the toilet. 
  2. Weigh the fecalyzer (about 9.7-10.7 grams). 
  3. Poo into a cup or wad of toilet tissue.
  4. Extract the green cage from the fecalyzer and plung the end into the poo.
    A clean plung with no dags is about 1gram.
  5. Return the green cage to the fecalyzer and weigh. Adjust until you have 1 gram of poo.
Note: Advise you use fresh poo. It probably doesn't matter too much (another thing we should investigate).
If you do experiments on the one sample over many hours then please make a note of it in your results.

Preparing the Fecalyzer

  1. In your work area place your Fecalyzer on several sheets of news paper (somewhere where spills are easy to clean up. Laundry?).
  2. Follow the fecalyzer instructions:
    1. Snap the green cage right down.
    2. Fill up to the mark (about 7 ml) with float solution (see Fecalyzer instructions).
    3. Twist the cage fully back and forward slowly 15 times to break up the poo and release the eggs.
    4. Use your dropper to overfill the fecalyzer to the top so a meniscus forms (about another 7 ml).
  3. Drop a 22 x 22 mm cover-slip on top of the meniscus and let it sit for 20 mins.
Note: Ensure volume of float solution is exactly the same on each analysis. Make sure you have a standardised method for preparation of the float solution. When you turn the cage back and forth be consistent with speed and frequency each time you do it.

Preparing the Slide

  1. After 20 mins the eggs have floated to the top. Lift the slip straight up (a glove is good here) and place onto a microscope slide.
  2. Place the slide on your microscope stage.

Egg Counting

  1. Use a 10x eyepiece and 10x objective lens. 
  2. Using the mechanical stage systematically move over the entire area of the cover slip.
    Start in one corner of the cover slip and step through sections using faecal debris to help you move to the next section.
    As you scan a section make small adjustments back and forward using the fine focus to catch eggs outside the current focal plane.
  3. Count all eggs observed under the 22 x 22 mm coverslip. 
    If you have time recount starting from the opposite corner. Note any error in count. Error will decrease as get better.
    Here a pen and paper is handy, or some use a cheap mechanical tally counter ($5 off amazon.com).

Clean up

  • Tip the fecalyzer fluid down the toilet and snap the lid closed.
  • Throw slides, fecalyzer, gloves etc together and wrap in paper. 
    Some toilet tissue around the items will soak up any spills. If you use a paper plate you can just fold in half and staple together.
  • Place in plastic bag and tie off. Do this carefully as you don't want a smelly bin.

What to Note

  1. Time of day (try a weekly count, same day, same time, same diet?).
  2. Note the faecal constancy (hard, soft, runny). When charting counts you should compare like with like.
  3. Note the egg count observed under the 22x22 mm cover slip.
  4. Note anything else you may think important (medication etc),
Experiment. Whatever you do you will get variation. However if the worms are struggling you will see a big drop followed by a big spike as they recover.

Photos

About 14 mls of float. Eye-dropper. Fecalyzer. On 2 paper plates to catch spills.

Pop the inner green cage out of the fecalyzer and use it to scoop up 1 gram of poo using your scales.

After adding 1g poo, push the green cage right down so it snaps into place
and fill the fecalyzer with about 7 ml of float solution (up to the bottom of the V mark).

Twist the back and forward fully about 15 times to release the eggs.

Add an additional 7 ml (approx.) of float and over fill the fecalyzer, forming a meniscus on top.

Gently place a 22x22 mm cover slip on top and let stand for 20 mins so the eggs float up and settle under the cover slip.

After 2 mins pick the slip straight up from the fecalyzer and dop onto a slide.

You can now move to the microscope and count all eggs under the slip using 100x magnification.

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