Understanding and preventing louping ill virus in sheep and its significant welfare impacts.
Louping ill causes severe neurological suffering in affected sheep. The virus crosses the blood-brain barrier and causes progressive inflammation of the central nervous system. Affected animals show fever, loss of appetite, depression, incoordination, tremors, and the characteristic 'louping' gait. Terminal cases experience paralysis, recumbency, convulsions, and death.
The welfare impact is particularly severe because progression from first signs to death may occur within days, and treatment is limited to supportive care. Survivors may have residual neurological deficits. The distress experienced during neurological disease is significant.
Vaccination is highly effective and is the cornerstone of prevention in tick-endemic areas of Scotland, Northern England, Wales, and Ireland. Tick control through acaricide treatment and pasture management reduces tick burdens and transmission risk. Early recognition and isolation of affected animals prevents unnecessary suffering.