Worm Control in Sheep: Why FEC Testing Matters

Managing internal parasites in sheep is essential for maintaining flock health, growth, and overall productivity. At Aorangi Vets, we use faecal egg count (FEC) testing to guide smarter worm control on Canterbury farms, helping you treat sheep only when necessary and with the right drench products.

Why FEC Testing Matters
Treating sheep without understanding worm burdens can lead to:

• Drench resistance – using the wrong drench or treating unnecessarily can reduce future options.
• Unnecessary costs – drenching when it’s not needed wastes money.
• Missed opportunities for effective control – treating too late or the wrong animals can affect flock performance.

How We Use FEC Testing

• Pre-drench testing: Confirms which sheep actually need treatment, making drenching more targeted and effective.
• Post-drench testing: Checks that the drench worked, giving early warning if resistance is developing.

At Aorangi Vets, FEC tests don’t just guide drenching, they help us understand your farm’s parasite patterns, grazing management, and seasonal risks. This knowledge allows us to provide advice tailored specifically to your flock, keeping your sheep healthy and your worm control program sustainable.

Getting Started with FEC Testing
For advice on how to collect faecal samples correctly, visit Beef + Lamb NZ – Collecting Faecal Samples.

Test kits are available from all Aorangi Vets clinics, and your vet can help you decide when to test, which animals to include, and which drench products are best for your flock.

Regular FEC testing with your vet protects the long-term effectiveness of drenches, safeguards sheep health, and ensures every dollar spent on parasite control is well invested.