Scotland alert as MV spreads
Scotland alert as MV spreads
MAEDI visna appears to be rising in sheep flocks and spreading to the north of England and Scotland, where it is thought to be rare.
In a letter to the Vet Record, Helen Buchanan, of the Vet Lab Agency, Thirsk, reports finding the disease in a Yorks flock. After the death of four old ewes, tests revealed that they were infected with MV.
It is typically seen in older ewes because it progresses slowly causing pneumonia symptoms and sometimes brain damage, although infection is picked up around birth. But MV can also lead to reduced growth rates in lambs in infected flocks because ewes suffer a type of mastitis, she says.
"MV is usually considered a disease of the south of England. But producers and vets should be aware that it could be present in the north and should follow eradication scheme guidelines to remain free of it," adds Miss Buchanan.
According to Barti Synge of SAC vet services, Inverness, which runs the Sheep and Goat Health Scheme, the disease is creeping up.
"There is evidence of antibody in sheep all over the country. There has also been a bad case reported in Lancs, recently. Once it becomes clinical in a flock, it can cause many cases of pneumonia.
"It seems to spread most when sheep are housed. Producers should also be careful to buy animals which are not infected." *