[Border disease: a persistent virus infection in sheep (author's transl)]

Area of Science:

• Veterinary Virology
• Sheep Pathology
• Congenital Infections

Context:

• Border disease (BD) is a significant congenital infection in sheep.
• Characterized by stillbirths, abortions, and weak lambs with neurological signs and abnormal hair coats.
• Affected lambs exhibit tremors, erratic gait, and potential inability to rise, impacting flock productivity.

Purpose:

• To describe the clinical presentation, etiology, and diagnosis of Border disease in sheep.
• To elucidate the pathogenesis of neurological signs related to defective myelinogenesis.
• To highlight the role of bovine virus diarrhoea (BVD) virus in BD and discuss diagnostic approaches.

Summary:

• Border disease is caused by a virus closely related to BVD virus, leading to congenital infection in sheep.
• Clinical signs include neurological deficits and hairy birthcoats, resulting from defective myelinogenesis.
• Diagnosis relies on clinical signs, antigen detection (immunofluorescence), virus isolation, and antibody detection in ewes.

Impact:

• Understanding BD pathogenesis aids in developing control strategies for affected sheep flocks.
• Identification of asymptomatic carriers is crucial for preventing continuous virus shedding and transmission.
• Distinguishing BD from other ovine neurological diseases is vital for accurate diagnosis and management.