Visna in a UK flock and the biosecurity risk arising from the onward sale of likely infected pedigree stock

Small ruminant lentivirus infections in sheep most commonly present with respiratory signs (maedi) and indurative mastitis, while primary neurological (visna) have rarely been reported Great Britain (GB). Most reports of visna describe referable to myelitis, although central associated encephalitis may feature. In this case, was diagnosed a 4-year-old ewe small pedigree flock, recently imported GB from northern Europe. Initial clinical findings were head tilt, circling, facial tremors unilaterally reduced menace response. These progressed include hyperaesthesia, ipsilateral hemiparesis recumbency. Flock level infection had by serology, the diagnosis individual case confirmed serology histopathology. The subsequent sale animals flock through large national auction at private sales raises significant ethical questions serves as reminder importance biosecurity precautions.