I was a biology major in college, so when I found out we could test our own fecal samples at home with a microscope instead of taking them to the vet I immediately bought one. It was a little pricey to purchase up front, but I figured it would pay off in the long run and I wanted to learn how to do it myself.
Fecal testing can be used, in combination with other tools, to help a goat owner figure out whether or not she needs to deworm her goats. Deworming too often can lead to medication resistance and treatment failure. Not deworming enough can lead to poor animal health and possibly death. One of the main goals of a fecal test is to determine how many worm/parasite eggs are present in the feces. This can help determine what the parasite load is in the animal. Generally speaking, ruminants (including goats) always have some level of infection by parasites and the name of the game is to keep the parasite load low, but one shouldn't expect to get rid of them completely.
In the first picture above you can see the microscope view of a parasite egg on a slide. There is also a lot of plant material and air bubbles in the photo. The second photo is a close-up of the egg (center of photo). The uniform circles around the egg (several of them) are air bubbles.
When performing a fecal test, the sample of feces is mixed with a "flotation solution." It helps free the eggs. A sample of the solution is then loaded onto a "McMaster" slide. This is a special slide that has a grid printed onto it. Once under the microscope, a person counts each egg inside the grid. Usually two separate grids are counted, added together, and then multiplied by a specific number (this number depends on approximately how many grams of feces was added to a specific volume of flotation solution).
If the number of eggs is very large, it might be time to consider deworming your goats. However, it is important to also consider other symptoms of high parasite loads: pale mucous membranes of the eyes and gums (FAMACHA testing - see resource below), rough hair coat, diarrhea, and weight loss.
Finally, you can use fecal testing to determine how well your current deworming medication is working using the fecal egg count reduction test. This basically involves doing a fecal test before deworming, and then again at the recommended time interval for your specific medication class (usually about 7-14 days after deworming).
Below are a few of my favorite resources regarding fecal testing and FAMACHA scoring:
"Fecal Egg Counting for Sheep and Goat Producers" by The University of Arkansas
"Why and How to do FAMACHA Scoring" by The University of Rhode Island and Virginia Tech
Here is the microscope I purchased: Eggzamin Standard Kit. This microscope comes with everything you need to start doing your own fecal testing. The charts and information on the pamphlets are super helpful.
Some educational institutions host workshops to learn how to do fecal exams, so be on the lookout for those if you are interested.
I hope this was helpful and that you might be inspired to start doing some of your own fecal exams on the farm!
Disclaimer: I am not a veterinarian and strongly advise you discuss any potential diagnoses and treatment options with your veterinarian first. This article is for informational purposes only. Riebel Farms LLC and its authors will not be held liable for any use of the information provided.