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Diagnosis of Internal Parasitism in Goats
Procedure for Conducting Fecal Egg Counts. The basic equipment needed to conduct fecal egg counts using a scale is shown. A microscope and McMaster fecal egg counting slide are also needed.
The McMaster fecal egg counting slide. Note the two chambers each having six counting lanes.
28 cc (ml) of flotation solution is put in a small dish.
2 grams of feces are weighed.
The 2 grams of feces is put in a tea-strainer placed in the small dish.
A teaspoon is used to mash the feces into the floation solution taking roughly 2 minutes.
The tea-strainer with the fecal residue is removed.
Stir the solution 8 times using a back-and-forth motion.
An eyedropper is filled with the fecal solution.
The first counting chamber of the slide is filled.
Stir the solution 8 times as before and using the eyedropper, fill the second counting chamber of the slide.
The slide is then placed on a microscope and viewed at 100X (10X objective and 10X ocular).
Find a corner of the counting chamber to begin counting.
Use air bubbles, which will be perfectly round and are shaded from light to dark from the center outward, to adjust the focus and look for worm eggs, which are blunt football-shaped objects. This pictute represents the view seen through the microscope. Beginning in one corner, count all the eggs in all lanes on both counting chambers. Multiply total count by 50 for eggs per gram
Close-up view of Haemonchus contortus eggs.
After counting the eggs, calculate the eggs per gram (EPG) to determine the need for deworming. Add the number of eggs found in each chamber then multiply by 50 to find EPG.
After calculating EPG, the above guidelines for Barberpole worm (Haemonchus contortus) can help in determining whether animals need to be treated. The Barberpole worm dominates during the warmer months of the year and causes most deaths in goats due to worms. However, during cooler times of the year, and especially in cooler climates, other roundworm species may predominate. Since these worms lay fewer eggs than the Barberpole worm, animals may need to be dewormed at lower EPG levels. Consult your local