Hairy Shaker Disease (Border disease)
By Dr Mackie Hobson BSc(Agric),BVSc

1. Diseases

Border disease has not been of any significance in Angora goats in South Africa.  In 1972 clinical signs suggested that Border disease may have been involved in abortions and antibody titres have since been detected.

Border disease (Britain) or hairy shaker disease (Australia and New Zealand) is a congenital disorder of lambs characterized by low birth weight and viability, poor conformation, tremor, and an excessively hairy birth coat. Goat kids may also be affected.

What causes the disease?

Border disease is caused by infection of the foetus in early pregnancy with a pestivirus (Flaviviridae). Sheep, cattle, goats, and pigs are also susceptible.

How is the virus transmitted?

The virus is most commonly introduced by the addition of infected sheep or pregnant ewes carrying an infected foetus. The virus may also be transmitted from infected cattle.

Transmission occurs through contaminated feed and water or aerosol transition through breathing contaminated material.

Infected lambs can shed the virus through urine and nasal secretions and ewes through uterine secretions.

How does the virus cause abortion?

Virus acquired in early pregnancy by previously unexposed animals crosses the placenta and invades the foetus. Placentitis occurs 10–30 days after infection and may cause foetal death with abortion, resorption, or mummification. Abortion may occur at any stage of pregnancy.

How does the ‘hairy shaker develop’?

When abortion does not occur the virus becomes widely distributed in foetal tissues and caused changes in the skin, skeleton, and CNS. Affected lambs may be born 2–3 days early, and many die before or at weaning.

BVD virus exposure

In flocks exposed to bovine viral diarrhea virus (BVDV), up to 50% or more of lambs born may be affected with border disease. Thereafter, the prevalence declines, although the disease may become endemic when “recovered” lambs are retained for breeding. However, sheep can also acquire infection from transiently or persistently infected cattle.

Clinical Findings:

• Late abortions
• Kids may lie but able to lift just their heads and neck (flavi virus)
• Undersized lambs with excessively hairy and sometimes excessively pigmented fleece.
• Skeletal abnormalities that may be seen in newborn lambs include a decreased crown-rump length, shortened tibia and radius, and a shortened longitudinal axis of the cranium.
• Some lambs exhibit involuntary muscular tremors, particularly of the trunk and hindlegs. The tremors are reduced at rest and exacerbated by purposeful movement.
• In others, skeletal defects such as dropped pasterns and mandibular brachygnathia may predominate.

Affected lambs have a poor survival rate. In survivors, nervous signs gradually disappear within 3–4 mo. Even in the absence of typical hairy-shaker lambs, outbreaks of low fertility in ewes and poor viability and ill-thrift in lambs may be associated with border disease virus infection.

Reference, Extract from

• By Robert J. Callan, DVM, MS, PhD, DACVIM, Professor, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University

           Andrea S. Lear, DVM,

• Kleinvee-siektes: Jan de Wet, Gareth Bath