Bovine Herpesvirus 2

Also know as: Bovine Herpes Mammillitis Virus — BHV-2

Introduction

Bovine herpesvirus-2 affects the teats and udders of cows as well as the perineum in some cases and occasionally the mouths and muzzles of suckling calves. It can also causes generalised disease in rare cases and lead to pseudolumpy skin disease. The disease is mostly seen in lactating cows. The virus is also zoonotic, causing lesions on the hands of milkers that touch the cow's lesions.

Transmission is by entry into the skin through trauma, such as from rough milking or poor milk machine quality or other types of teat trauma.

Signalment

Usually dairy cattle in milk. It can also affect the muzzles of suckling calves.

Clinical Signs

Signs include the appearance of the lesions, which are generally moist, raised erosions or plaques found on the teat and udder. The cow may develop secondary bacterial mastitis and her milk production may drop.

Diagnosis

Characteristic lesions can lead to a presumptive diagnosis. Definitive diagnosis is by virus isolation from a sample of the lesion.

Treatment and Control

Control measures include ensuring the milking machine is in full working order with no faults e.g. check the pressure and clean or replace teat liners to prevent teat damage, which allows virus entry.

If treatment is necessary, then there are topical antivirals available where this is economically viable. There are no vaccines against this virus.

References

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

Merck & Co (2008) The Merck Veterinary Manual (Eighth Edition) Merial

Russell, P (2007) Virology Study Guide, Royal Veterinary College