Livestock

Worm Control in Sheep: Welfare and Resistance Management

How strategic worm control improves sheep welfare while managing anthelmintic resistance.

Key Facts

Gastrointestinal nematodes are the major cause of ill health in sheep globally
Haemonchus contortus causes acute anaemia and death in warm climates
Anthelmintic resistance is now widespread — threating welfare and production
Targeted selective treatment based on FAMACHA and FEC reduces resistance selection

Welfare Considerations

Worm burden causes poor growth, anaemia, diarrhoea, and death — particularly in young lambs. Welfare-focused control balances effective treatment with resistance management. Routine blanket treatment drives resistance and reduces future treatment effectiveness. Targeted selective treatment protects the most vulnerable animals while reducing selection pressure.

What You Can Do

Use FAMACHA and faecal egg counting to guide targeted treatment decisions
Work with your vet to develop a resistance management plan for your flock
Test anthelmintics for efficacy using faecal egg count reduction tests annually