{"id":17740,"date":"2025-01-09T13:18:44","date_gmt":"2025-01-09T13:18:44","guid":{"rendered":"https:\/\/herdwatch.com\/en-uk\/?p=17740"},"modified":"2026-05-25T08:58:46","modified_gmt":"2026-05-25T08:58:46","slug":"maedi-visna-in-sheep","status":"publish","type":"post","link":"https:\/\/herdwatch.com\/en-uk\/blog\/maedi-visna-in-sheep\/","title":{"rendered":"Maedi-Visna Virus – What you need to know"},"content":{"rendered":"\n
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Farmer Guide<\/div>\n\n

Maedi-Visna (MV) in sheep: understanding the risk and protecting your flock<\/h1>\n\n

\n Maedi-Visna (MV) is a chronic viral disease that can significantly impact flock health and productivity.\n Early detection, strong biosecurity, and accurate records are key to controlling its spread and protecting your flock.\n <\/p>\n\n

\n Sheep health<\/span>\n Disease control<\/span>\n Farm compliance<\/span>\n <\/div>\n <\/div>\n <\/div>\n\n
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\n 1<\/span>\n Chronic viral disease affecting sheep<\/span>\n <\/div>\n
\n 2<\/span>\n Slow to develop but highly contagious<\/span>\n <\/div>\n
\n 3<\/span>\n Can reduce productivity and performance<\/span>\n <\/div>\n
\n 4<\/span>\n Strong biosecurity helps reduce spread<\/span>\n <\/div>\n <\/div>\n <\/div>\n\n
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What is Maedi-Visna?<\/h2>\n\n

\n Maedi-Visna (MV) is a chronic viral disease affecting sheep, caused by the Maedi-Visna Virus (MVV),\n which belongs to the lentivirus family. It was originally introduced into the UK through imported sheep\n and has since spread, particularly within commercial flocks.\n <\/p>\n\n

\n MV primarily affects the respiratory and nervous systems, leading to chronic pneumonia (Maedi)\n and progressive wasting (Visna). It is a slow-developing disease, with symptoms often taking years to appear.\n <\/p>\n\n

\n \u201cMV can spread within a flock long before symptoms appear, making early detection and prevention essential.\u201d\n <\/div>\n\n

\n Although the virus is not zoonotic and does not affect humans, it is highly contagious between sheep.\n Infected animals can spread the virus before showing any visible signs, making control particularly challenging.\n <\/p>\n <\/div>\n\n

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Clinical signs of MV<\/h2>\n\n

\n Because MV develops slowly, symptoms may not be immediately obvious. Over time, affected animals may show:\n <\/p>\n\n