Genetic selection for resistance to internal parasites reduces treatment requirements and welfare impacts in sheep. This approach offers a sustainable long-term solution.
Sheep with low genetic resistance to parasites require more frequent treatment and still suffer higher parasite burdens between treatments. Selecting for resistance creates animals that are inherently better able to tolerate and control parasite challenge, reducing both treatment requirements and the welfare impacts of heavy worm burdens. This genetic approach addresses the root cause rather than the symptom.