Immunocompromised Horses
“Shaggy Steed A sturdy horse with a long, flowing mane and tail stands proudly against a dusty barn wall, its expression calm and trusting.” by Lila Patel, licensed via Adobe Stock
Parasites & Immunocompromised Horses: Why Extra Vigilance Matters
Horses with weakened immune systems—whether due to age, illness, stress, or underlying health conditions—are at greater risk for parasite-related problems.
Even a parasite burden that a healthy horse might tolerate can lead to serious complications in an immunocompromised horse.
Why These Horses Are More Vulnerable:
Weakened Defense – Their bodies can’t fight off parasites effectively, allowing worm burdens to build up quickly.
Subtle Symptoms, Serious Impact – Issues like weight loss, diarrhea, poor coat condition, or low energy may seem mild but can indicate a dangerous internal problem.
Greater Risk of Complications – Parasites can trigger or worsen colic, ulcers, laminitis, or nutrient deficiencies.
The Solution? Regular Faecal Egg Counts (FECs)
FECs help you monitor parasite load in real time—especially important when the immune system isn’t providing reliable protection.
FECs reveal which horses are shedding the most eggs
Allow for targeted, effective deworming
Help avoid unnecessary or inappropriate treatments
Protect against parasite resistance, a growing concern in modern equine care
What You Should Do:
Collect a fresh manure sample
Submit it for a faecal egg count every 8–12 weeks
Develop a deworming program based on FEC results on your own, with help from myself or work with your vet
Maintain good pasture hygiene to reduce parasite exposure
Pro tip: Don’t assume what works for one horse will work for all—immunocompromised horses need individualised care.
A few extra steps can make all the difference in protecting your horse’s health.
Reference: This content is adapted from current veterinary parasitology guidelines, including the American Association of Equine Practitioners (AAEP) and the World Association for the Advancement of Veterinary Parasitology (WAAVP), with additional insights based on clinical considerations for immunocompromised horses.
