Winter Dysentery

Also Known as: Bovine Coronavirus

Introduction

Winter diarrhoea is a disease of adult cattle worldwide, caused by coronavirus. Campylobacter may also contribute to severity and clinical signs of the disease. The disease is more common in dairy cattle than in beef cattle.

Clinical Signs

Adult cattle are affected plus the time of year (when cattle are housed). Cattle will be in good condition as this is an acute and transient disease. Signs are acute and up to 100% of the herd may be affected over a period of 2 - 3 weeks as it passes through the herd.

There will be transient diarrhoea of around 2 - 3 days duration and the diarrhoea will appear watery, black/green and will be profuse. Blood is visible in the diarrhoea in many cases.

Dramatic decrease in milk yields may also be noticed.

Diagnosis

Diagnosed on clinical signs, history and signalment. No diagnostic tests should be performed, but if in doubt, other causes of adult diarrhoea e.g. Johnes disease or Salmonella may be tested for.

Treatment and Control

This is a sporadic disease and no treatment is necessary. In severely affected cattle, electrolyte solution may be given to help treat the dehydration from diarrhoea.

Control measures include trying to maintain good hygiene measures during winter housing.

References

Andrews, A.H, Blowey, R.W, Boyd, H and Eddy, R.G. (2004) Bovine Medicine (Second edition), Blackwell Publishing

Radostits, O.M, Arundel, J.H, and Gay, C.C. (2000) Veterinary Medicine: a textbook of the diseases of cattle, sheep, pigs, goats and horses Elsevier Health Sciences