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
- Take your scales and a fecalyzer to the toilet.
- Weigh the fecalyzer (about 9.7-10.7 grams).
- Poo into a cup or wad of toilet tissue.
- Extract the green cage from the fecalyzer and plung the end into the poo.
- A clean plung with no dags is about 1gram.
- 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
- In your work area place your Fecalyzer on several sheets of news paper (somewhere where spills are easy to clean up. Laundry?).
- Follow the fecalyzer instructions:
- Snap the green cage right down.
- Fill up to the mark (about 7 ml) with float solution (see Fecalyzer instructions).
- Twist the cage fully back and forward slowly 15 times to break up the poo and release the eggs.
- Use your dropper to overfill the fecalyzer to the top so a meniscus forms (about another 7 ml).
- 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
- 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.
- Place the slide on your microscope stage.
- Use a 10x eyepiece and 10x objective lens.
- 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.
- 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).
- 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
- Time of day (try a weekly count, same day, same time, same diet?).
- Note the faecal constancy (hard, soft, runny). When charting counts you should compare like with like.
- Note the egg count observed under the 22x22 mm cover slip.
- 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.
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.