7 July 1995

Vaccine offers new hope in the battle to defeat BVDV

By Sue Rider

THE UK cattle industry could stem the £70m a year lost to bovine viral diarrhoea virus (BVDV) if a new vaccine developed against the disease lives up to early expectations.

The vaccine, the first to be available in the UK for BVDV, has been developed by the Institute of Animal Health, Compton, Berks.

IAH researchers, speaking at the new Animal Health focus at the Royal, heralded the vaccine as a huge breakthrough given that the 200 BVDV vaccines available in the US were of little use.

They also pointed to the urgent need for an effective vaccine in view of the increased incidence of a super-virulent strain of BVDV that has appeared in UK herds since 1992.

The super strain kills non-pregnant adult animals, while the acute infection causes little harm in adult stock. But the more common BVDV infection is a concern among pregnant animals.

"When the infection hits in early pregnancy it can cause abortion or calf defects," said an IAH researcher. Surviving calves would be infected for life and at six to 12 months would develop mucosal disease.

"The animal goes off its food, suffers severe diarrhoea, and gets sores on its nose and tongue," added the IAH researcher.

She said that up to 2% of calves born from the UK dairy herd would be infected persistently with BVDV. Of those, more then 90% would develop mucosal disease.

The new vaccine, Bovidec, to be made by Grampian Pharma-ceuticals, should be available by the end of the month if it got the all clear.

The researchers recommended producers gave all heifers two doses of the vaccine three weeks apart, with the second dose one week before service. The IAH believes the vaccine would provide four weeks immunity. The animal would then require an annual booster.

"Producers with closed herds should screen their animals to pinpoint whether they have a persistently infected animal," said the IAH. "If they find none, it is still necessary to screen every replacement bought in as the herd would only be safe from infection if genuinely isolated. Most herds will have to vaccinate annually."