Livestock

Coccidiosis in Sheep: Welfare and Outbreak Management

Welfare guide to ovine coccidiosis -- a common disease of young lambs causing significant suffering and mortality.

Key Facts

Coccidiosis is caused by Eimeria ovinoidalis and E. crandallis -- parasites that destroy intestinal cells
It primarily affects lambs between 4 and 8 weeks of age when maternal immunity wanes
Clinical signs include profuse watery diarrhoea, dehydration, straining, blood in faeces, and rapid weight loss
Severe cases cause gut damage that persists even after the acute infection resolves
High stocking density around feeding areas concentrates oocysts and dramatically increases transmission risk
Diclazuril and toltrazuril are effective treatments when given promptly
Prevention focuses on reducing stocking density, improving hygiene in lambing areas, and metaphylaxis in high-risk groups
Subclinical coccidiosis without diarrhoea impairs growth rates -- a hidden welfare burden

Welfare Significance

Coccidiosis causes intense suffering in affected lambs -- the combination of diarrhoea, abdominal pain, dehydration, and exhaustion represents a severe welfare burden. The disease can move from first signs to severe illness within 24-48 hours. Early recognition and treatment, combined with reduction of environmental contamination, are the most welfare-effective responses.

What You Can Do

Monitor lambs between 4 and 8 weeks closely for diarrhoea -- act within 24 hours of first signs
Treat with appropriate coccidiocide medication promptly and continue for the full course
Reduce stocking density around feeding areas during the high-risk period
Consider metaphylaxis with diclazuril in high-risk flocks before the expected disease peak