A livestock disease surveillance service has advised Pembrokeshire farmers to store cattle food and water away from dogs and foxes to avoid an infection which can lead to abortion.

The advice from the National Animal Disease Information Service follows the publication of data showing a big increase in livestock abortion this spring.

One of the most recently identified causes is neosporosis with dogs and foxes said to be a potential source of infection.

NADIS vet Mike Howe, who is based in Pembrokeshire, said studies found that neosporosis caused over 10% of all abortions in UK cattle.

However, as a large number of healthy calves can be infected with the protozoa, neospora, other causes of abortion, particularly BVD or leptospirosis, should be eliminated before diagnosis is made, suggested Mr Howe.

High hygiene standards at calving and careful storage of cattle food and water were important means of preventing infection, he explained.

However, transmission from mother to calf, was far more important, he stressed. "Over 90% of calves born to mothers with antibodies to neospora will have been infected in the womb," said Mr Howe.

According to a report by Richard Laven, manager of the Scottish Agricultural College's surveillance centre, farmers should identify infected cattle and cull them.

Also, only seronegative cattle should be selected for breeding, he advised.

"Heifers with antibodies should be sold for meat and not bred from," said Mr Laven.

"These strategies look expensive to achieve, however the cost of neosporosis far outweighs the cost of eliminating it from the herd."

Research by the National Animal Disease Information Service, a network of veterinary practices and colleges monitoring diseases in the UK livestock industry, is sponsored by the Milk Development Council, the Meat and Livestock Commission, Elanco Animal Health and Intervet.