Livestock Welfare

Bovine Malignant Catarrhal Fever: Welfare and Recognition

Understanding bovine malignant catarrhal fever (MCF) — a severe viral disease with significant welfare implications.

Key Facts

MCF is caused by herpesviruses (OvHV-2 from sheep, AlHV-1 from wildebeest) transmitted to cattle
The disease causes high fever, severe ocular and nasal discharge, and neurological signs
Mortality in clinically affected cattle approaches 100%
Cattle and deer are dead-end hosts — the disease does not spread between cattle
Prevention focuses on separating cattle from sheep, particularly during lambing

Welfare Considerations

Bovine malignant catarrhal fever causes severe acute suffering in affected cattle. The disease progresses rapidly from high fever and depression to severe multisystemic disease. Profuse nasal and ocular discharge, corneal opacity causing blindness, oral ulceration, skin lesions, diarrhoea, and neurological signs all occur. Affected animals are acutely and severely ill.

There is no effective treatment. Once clinical signs develop, death is almost inevitable. Supportive care may provide brief palliation but does not alter the outcome. The suffering experienced during the 3-10 day clinical course before death is significant and constitutes a serious welfare concern.

Prevention is the only effective strategy. The key measure is separating cattle from sheep during lambing, when OvHV-2 shedding from lambs is highest. On farms where separation is impossible, close monitoring for early signs allows prompt euthanasia to minimise suffering duration.

What You Can Do

Separate cattle from sheep during the lambing period to prevent MCF transmission
Learn to recognise early signs of MCF — fever, ocular discharge, depression
Implement prompt euthanasia for confirmed MCF cases to prevent prolonged suffering
Discuss farm layout and separation strategies with your vet
Report suspected MCF cases to APHA — surveillance supports understanding of disease distribution