Eradicating BVD in the UK – where are we now, and where are we heading? We spoke to a leading cattle vet and the technical director of Wales’ BVD eradication scheme to find out.
TEXT RACHAEL PORTER
Control and eradication of bovine viral diarrhoea (BVD) varies throughout the UK, with each nation operating its own distinctly different scheme. As a result, England, Scotland, Northern Ireland and Wales are at different stages on the journey towards becoming BVD free.
But a couple of recent industry developments and announcements could be the catalyst to push each of the nations forward towards achieving BVD-free status at a faster rate. In July 2021, the Ruminant Health and Welfare Group set the industry a target to be free of the disease by 2031.
“This target should focus the minds of all vets and producers involved in each devolved country’s schemes,” says Wales-based Gwaredu BVD’s technical director Neil Paton, who is also a farm animal lecturer at the Royal Veterinary College.
“Becoming BVD-free is the ultimate goal of all the schemes. It’s good to see the ambition stated so clearly and I’m confident that all countries can meet it. It’s just nine years away and some schemes are further ahead than others. Scotland and Northern Ireland, with their compulsory schemes, are leading the field and lighting the way for England and Wales,” he says. Boehringer Ingelheim Animal Health vet Kath Aplin says that in England many producers are still unaware of their herd’s BVD status and are yet to put measures in place to control the disease. “More work will certainly be required to hit the 2031 target. But the Health and Welfare Pathway, unveiled in late 2021, is an exciting development and will help those herds not currently participating in a BVD eradication scheme to get a foot on the ladder, and start on the path to achieving BVD-free status,” she says.
Although the BVD schemes across the UK vary, there are some interesting – and useful – aspects from them all. Unsurprisingly, producers’ engagement with BVD schemes varies depending on whether the scheme is compulsory or voluntary, though the voluntary, vet-led scheme in Wales has seen rapid and high levels of uptake. “That’s certainly our experience,” says Dr Paton, adding that close to 90% of all herds have been tested for BVD at least once. Almost all producers are engaged and keen to start.
“It’s unlikely that any scheme would get 100% uptake on a voluntary basis, so I think making BVD testing mandatory would certainly help to mop up the remaining producers who have yet to sign up,” Dr Paton adds. Producers’ response to BVD being detected in their herd varies, with some producers in all schemes still attempting to rear persistently infected (PI) animals (see Figure 1).
Figure 1: Fate of P1 animals (National BVD Survey 2021)
“Prompt removal of PIs is critical to the success of any scheme,” adds Dr Paton. “This is an area all devolved-country schemes need to focus on, with clear messages around removing PIs as soon as they are identified.” England’s forthcoming Animal Health and Welfare Pathway, which is linked to the Government’s new support package for agriculture, will help English producers on the journey towards BVD eradication. Beginning in spring 2022, it will include a funded annual vet visit – worth £372 for dairy businesses – free for all eligible BPS units with 10 or more cows, with a focus on BVD for herds that are not already linked to a scheme.
“The visit will focus on current BVD status, data collection and biosecurity, with the aim being to develop a robust plan for becoming and remaining free of BVD,” says Ms Aplin.
“The herd’s own vet is the key to successfully tackling BVD. Building on what is often already a strong relationship between producers and their vet, the pathway is an opportunity to review and plug any gaps in existing BVD control plans, or start afresh if BVD hasn’t previously been tackled on the farm. With BVD being so prevalent, there’s potential for big gains, both in terms of animal welfare and bottom-line for the business,” she adds.
The Scottish BVD eradication scheme has been mandatory since 2013. Around 90% of Scottish herds are BVD negative, and herds are really seeing the benefits, including healthier calves and reduced antibiotic use. “At this stage in the scheme, vaccination continues to play a vital role in keeping herds protected,” says Ms Aplin. “There’s a much lower risk of cattle being exposed to BVD now, compared with at the start of the scheme, but there’s also less natural immunity, so the consequences are potentially serious.”
“In Wales, Gwaredu BVD has focused on the serological screening of young stock, taking advantage of annual vet visits to cattle farms,” says Dr Paton. “The voluntary phase of the scheme will continue until December 2022.” He says the challenge for Wales, as with other voluntary schemes, has been to continue developing producer engagement once the initial early adopters have signed up.
As in Scotland, policymakers for Wales are looking at where to take the scheme next. Options include legislation, mandatory surveillance, movement restrictions and, in some cases, inspection of facilities. Northern Ireland’s scheme became compulsory in 2016 and engagement is correspondingly high, with 20,779 herds participating as of December 2021. Surprisingly, but also in line with what’s seen in other nations, 102 PI animals remained in the national herd at that stage. “The vet’s role in communicating the requirement and benefits of removing any PI immediately upon identification cannot be under-estimated,” adds Ms Aplin.
Mandatory or not, all schemes require buy-in from producers. “Some producers are more engaged in BVD eradication than others. The aim of all programmes is to work with producers to tackle this important disease in an effective and practical way,” adds Dr Paton. “One missing link from all the schemes is the role played by a planned vaccination programme. There’s little point in testing to eradicate a disease if a herd is then left vulnerable to exposure due to poor biosecurity.” In his experience, once producers start to vaccinate against BVD, and see the benefits in terms of herd health, welfare, fertility, productivity and peace of mind, they continue – even when the herd is officially BVD free.
“BVD compromises immunity and, as a result, makes herds more susceptible to disease. Producers don’t want to risk the disease re-entering their herd. Even the most robust biosecurity policy can’t always keep it out. So vaccination is an insurance policy.”
More information about the Animal Health and Welfare Pathway, and funding available can be found at https://defrafarming.blog.gov.uk/2021/09/09/introducing-the-animal-health-and-welfare-pathway.