Managing equine health requires a thoughtful approach, and parasite control is one of the most important areas to address. Among the tools available to horse owners, the fecal egg count (FEC) is one of the most practical and cost-effective methods for monitoring parasite burdens. Far more than just a manure test, an FEC provides actionable insights that support targeted deworming strategies, protect the effectiveness of deworming products, and ultimately promote healthier horses.
What Is a Fecal Egg Count?
A fecal egg count measures the number of parasite eggs present in one gram of a horse’s manure. Most often, the test focuses on strongyle eggs, which come from adult worms residing in the large intestine. Strongyles are among the most concerning internal parasites due to their impact on digestion and nutrient absorption.
In the lab, manure is mixed with a flotation solution, placed under a microscope, and the number of eggs is calculated. Results are expressed as eggs per gram (EPG).
Why Fecal Egg Counts Matter
1. Targeted Deworming
For years, rotational deworming was the standard practice. However, this approach led to overuse of deworming products and widespread anthelmintic resistance. An FEC allows for evidence-based parasite management. Instead of treating all horses equally, owners can identify which horses are high shedders and focus treatment accordingly.
2. Drug Resistance Management
Resistance to dewormers is one of the most urgent challenges in equine care. Once parasites become resistant, it cannot be reversed. By using fecal egg counts, horse owners can help preserve the long-term effectiveness of deworming products.
3. Horse-Specific Insights
Not all horses carry the same parasite burden. Research shows that about 20–30% of horses shed the majority of parasite eggs in a herd. Identifying those individuals means fewer unnecessary treatments for low shedders.
4. Herd Health Monitoring
FEC results give valuable information at the herd level. If multiple horses are testing high, management practices may need attention — such as manure removal, pasture rotation, or stocking density.
When Should You Perform a Fecal Egg Count?
Timing often depends on regional climate and parasite life cycles. Generally:
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Spring: A baseline test to assess shedding before parasites increase in warmer months.
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Summer/Early Fall: Follow-up counts track program effectiveness.
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After Deworming: A fecal egg count reduction test (FECRT) two weeks post-treatment confirms whether a dewormer worked.
Always consult your veterinarian for guidance tailored to your horse and environment.
What FEC Results Can Tell You
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Low shedders: <200 EPG
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Moderate shedders: 200–500 EPG
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High shedders: >500 EPG
This classification helps identify which horses are most responsible for pasture contamination. The aim isn’t to eliminate all parasites but to keep levels low enough that they don’t impair health or performance. For further understanding, consult your veterinarian.
Beyond Deworming: Nutrition and Management
From an equine nutritionist’s perspective, parasite control is only one piece of the puzzle. Supporting a horse’s immune system and digestive health makes them more resilient:
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Protein and amino acids support tissue repair and immune function.
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Trace minerals like copper, zinc, and selenium are essential for immunity.
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Forage-based diets maintain gut integrity.
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Pasture management — regular manure removal, cross-grazing with ruminants, and reduced stocking density — lowers parasite exposure.
👉 Explore equine nutrition products at The Mill to support overall horse health.
Frequently Asked Questions About Fecal Egg Counts
How often should you do a fecal egg count on your horse?
Most horses benefit from testing 1–2 times per year — spring and fall are common checkpoints. Frequency varies depending on age, management, and environment.
What does a fecal egg count tell you?
An FEC measures eggs per gram (EPG) of manure, classifying horses as low, moderate, or high shedders. This guides targeted deworming and monitors treatment effectiveness.
Do all horses need to be dewormed?
Not always. About 20–30% of horses shed most parasites in a herd. With FEC results, owners can focus treatment on those horses and avoid over-treating others.
What is anthelmintic resistance and why is it important?
It’s when parasites adapt to survive dewormers that once worked. Overuse has made resistance a global issue in horses. FECs help slow this trend by guiding selective treatments.
Can nutrition help reduce parasite loads in horses?
Yes. While nutrition doesn’t replace parasite control programs, a balanced diet strengthens the immune system and gut health, making horses more resilient.
How do you collect a sample for a fecal egg count?
Use fresh manure (less than 12 hours old), collected from the top of a pile to avoid soil. Place it in a clean, sealed bag and keep it cool until it reaches your vet or lab.
👉 Need help with horse care basics? Visit our equine blog hub for more guides.
Key Takeaways
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Fecal egg counts are a critical diagnostic tool for informed parasite management.
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They help reduce unnecessary deworming, preserve product effectiveness, and provide horse-specific insights.
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Pairing FECs with balanced nutrition and smart management supports long-term herd health.
By incorporating fecal egg counts into your routine care, you’re not only protecting your horse today. You’re also safeguarding the effectiveness of parasite control for the future.
Next Step: Take fecal samples in for testing. Discuss the results with your veterinary and visit any one of The Mill’s 8 locations for equine supplies, feed, supplements, dewormers, and pasture management products that support a healthier herd.
