Parasite Patrol

Fecal tests for parasite eggs have become a crucial part of any effective deworming program. Here’s how to ensure that those tests are accurate and meaningful.

- Barb Crabbe

Poop shows up at my equine veterinary clinic in many different ways—packaged in plastic bags and delivered in the mail, wrapped up in exam gloves in the back of our doctors’ trucks, or carried in by owners in a bucket or a scoop. Sometimes it just appears on our doorstep with a name and a note, “Trigger Jones’ poop.” Usually we know the horse it came from, when he was last dewormed, and what kind of an environment he lives in. But sometimes we don’t. And while we can perform a fecal test on any sample and report results, that information is only meaningful if it’s been collected at the right time and packaged properly.

If you’ve adopted a strategic deworming plan for your horse—that is, one that includes fecal testing—good for you! You’ve been paying attention to the research about emerging resistance to available dewormers. You understand that all dewormers aren’t created equal, horses have varying requirements, and timing makes a difference. Because fecal egg counts provide the evidence you need to make the right deworming decisions for your horse, it’s important to understand what those tests really tell you, and how to make sure you’re getting the right results.

Here, I’ll answer five important questions about fecal testing. With this information, you’ll know when and how to collect a sample, what type of test to ask for, and what to do with the results.

Question #1: When should you test?