Bovine viral diarrhoea (BVD) was recognised as a priority disease by the Welsh Government in their Animal Health and Welfare framework group implementation plan in 2013. As a result, Gwaredu BVD was established as a voluntary scheme to deliver the Welsh BVD eradication programme. It is an industry-led programme dedicated to supporting farmers.
The decision to make BVD a priority disease was significantly influenced by the efforts of Scotland and Ireland in eradicating BVD from their national herds. The Welsh BVD eradication programme has benefited enormously from the lessons learned and the sharing of knowledge.
Benefits of eradication
Eradicating BVD has many benefits for cattle industries. These range from removing financial restrictions to increasing farm profitability. The reduction in disease burden accounts for this, and improves health and welfare. This improvement in health and welfare is likely to lead to better mental health for farmers as concerns around cattle health are alleviated.
As these limitations on businesses are removed, the need for antimicrobial usage is reduced and the chance of resistance occurring is reduced. All of these benefits are likely to result in a reduction of the carbon footprint of cattle farms.
Both farmers and veterinary surgeons will gain from the experience of eradicating disease on farm, and it is hoped that this will be evident in greater confidence in dealing with other diseases on farm. This will enhance the veterinary surgeon–farmer relationship from detailed discussion of disease control on farm, to the technical confidence in taking blood samples.
For the industry as a whole, BVD freedom will enhance the reputation of farming in Wales, improving its viability, and maintaining farming as part of the Welsh culture and language in rural communities.
Rationale for surveillance testing
In order to facilitate implementation, a technical group was established consisting of leading experts from all over the UK to discuss and decide on the most applicable approach to eradicate BVD in Wales. Two approaches were considered: the tag and test route (Irish model/approach); and the use of check tests followed by persistently infected (PI) hunts in exposed herds (the initial Scottish approach. Following trial work, subsidised by Hybu Cig Cymru, it was predicted that around 75% of Welsh cattle herds were naive to BVD antibodies. Thus, it was decided that the check test approach was the most suitable for Wales/the Welsh cattle industry and this was confirmed in the first months of the programme (Paton, 2018).
The design of the Welsh BVD eradication programme has been based on the approach that for herds that screen antibody negative (naive) there should be minimal cost, effort and disruption to their businesses. A frequent question is ‘Why not just tag?’ and apart from the appropriate allocation of limited resources, antibody testing will not be affected by abortions, still births, and barren cows being omitted from testing on farms.
Gwaredu BVD data demonstrate that with 28% of the 9272 herds screened in Wales testing antibody positive during their youngstock screen, it was correct to take this route. The choice to perform BVD surveillance testing at the annual bovine tuberculosis (bTB) test also proved popular as it enabled testing to be performed when animals were already gathered and a veterinary surgeon was present on the farm, thus using available resources (farmer and veterinary time) incredibly effectively. Furthermore this empowers the veterinary surgeon to deal with an infectious disease on farm and it was an ambition of the Gwaredu BVD programme that veterinary surgeons would gain confidence in managing disease on farm.
Gwaredu BVD funding and delivery
Funding for the delivery of a voluntary programme was made available in 2017 for 5 years when the Welsh Government awarded £10 million to Coleg Sir Gar in partnership with the Royal Veterinary College to deliver the programme. The Gwaredu BVD programme was launched at the 2017 Royal Welsh Show and began national screening in September 2017 with check tests conducted on farm alongside routine bTB. This enabled a large number of farms to be targeted in a short time period by combining with other routine infectious disease surveillance. Gwaredu BVD funding towards PI hunting commenced approximately 3 months later in January 2018 and was targeted at farms that had failed a check test. This allowed appropriate allocation of finite resources.
Scheme structure and testing as used by Gwaredu BVD
All cattle farms are eligible for a free check test per management group annually. It is the decision of the farm's veterinarian how many management groups are sampled with some farms having many groups being checked.
This allows farms to be categorised either as BVD free or that they have evidence of BVD on farm. Where there is evidence of disease, financial support is available to identify the PI animals on farm (Figure 1).
While, as was previously stated, the use of tissue tags is not part of the surveillance strategy of Gwaredu BVD, it is a rational choice for the detection of newborn PI animals. Tags along with blood sampling for antigen detection and bulk milk testing are options available to the farmers and veterinary surgeons that need to carry out testing to identify any PIs that may be present on farm. It remains the farmer's responsibility to determine the fate of the PI. Gwaredu BVD recommends that the animal is slaughtered as soon as possible.
In all cases, it is expected that appropriate biosecurity advice is given, veterinary continuing professional development (CPD), both in person and online, is provided to support this. To allow farmers to educate themselves, leaflets and other resources are produced to improve biosecurity practices on farms in Wales.
Scheme successes to date
Of the 11 000 Welsh cattle herds (beef and dairy), 9272 have had a check test at least once through this voluntary programme, as of October 2022. This represents 84% of all cattle herds voluntarily participating in the programme.
This success is attributed to a number of factors and the significant support and backing provided by the whole cattle industry in Wales. This includes, but is not limited to:
- Government funding to establish a national programme
- Free and simple check test offered to farmers on an annual basis
- The ability to incorporate the check test with the annual bTB test when animals are gathered and veterinary surgeons are present on farm
- Raising industry awareness about the disease via a comprehensive communication strategy
- Veterinary surgeon collaboration and engagement
- Industry stakeholder support and continual engagement
- Commitment by the Welsh Government to consider the introduction of legislation if the initial voluntary programme achieved sufficient uptake.
A particular success is the acceptance and the value perceived by the farmers of the Gwaredu BVD certificate. While it only truly reflects the number of years a farm has tested antibody free, they are something farmers are rightly proud of. Certificates are displayed at point of sale and at shows to advertise the status of cattle. As part of the Gwaredu BVD programme, farms that screen antibody negative receive a herd status certificate, ranging from bronze (3357 farms currently at this status) to gold (2179) based on the number of years continuously screened and clear.
These certificates are designed to be used when marketing stock to demonstrate their herd's freedom from BVD and encourage informed purchasing. It is also hoped that these will keep famer engagement as they work to achieve and retain the reward of a certificate. The loss of certificate status, particularly gold, is not taken lightly. The Gwaredu BVD team receive numerous enquiries surrounding how to achieve gold status, and why they have sometimes been demoted.
It is indisputable that eradicating BVD would significantly enhance the health, welfare and reputation of Welsh agriculture.
Gwaredu BVD has demonstrated that BVD eradication is important to the Welsh cattle industry. Gwaredu BVD stakeholders, and in particular the farming unions, are keen to see the gains made retained into the future. It is recognised by Gwaredu BVD that this will require legislation to succeed. In this, Gwaredu BVD has gained Welsh government support in considering legislation. The Welsh Government launched a consultation on the 30th of June 2022, which closed on the 25th of August 2022. Following this, the industry is awaiting a government response to the answers to the consultation. It is to be hoped that the next phase continues with a familiar mechanism of Gwaredu BVD to minimise confusion within the farming community. Gwaredu BVD are strongly advocating for no gap between the voluntary phase and implementation of legislation, which may require an extension of the programme into a ‘Transition’ phase.
Exit strategy
The benefit of the approach outlined above is that the exit strategy is embedded in the check test. Sufficient negative antibody testing will demonstrate freedom from BVD in the Welsh herd. With Scotland already well on the way, and England making plans, it is not inconceivable that BVD testing could be eliminated and supplanted with other disease testing to produce a healthier national herd.
Challenges on the journey towards eradication
Cross border trade
Although cattle are traded from all over the UK, the England-Wales land border poses a major disease risk because of the large numbers of cattle crossing, and essentially over the fence contact of cattle. Hundreds of cattle cross this border daily. It is therefore, critical to the success of the Welsh programme that the English BVD eradication scheme is also prioritised. It is important that cattle movements are managed in such a manner that BVD is not transported with them.
Eradication fatigue
Keeping farmers and veterinary surgeons engaged and enthused with the need to eradicate BVD over several years is a challenge. Repeated extensions are of particular concern with farmers losing faith that legislation will actually be enacted. Stakeholders will likely need clear signposting of progress to date and the direction of travel to avoid the perception of an aimless, neverending programme of testing without an endpoint.
Persistently infected removal
To eradicate BVD it is imperative that all identified PIs are immediately isolated and culled at the earliest opportunity. There is no compensation provided in the Welsh BVD eradication programme. Evidence from the first 300 PIs identified demonstrated that 25% were culled, 50% retained on farm and 25% moved to other farm holdings. This highlights the significant challenge that will require legislative support to prevent the movement of PIs (unless to slaughter) to other holdings, and encourage farmers to cull rapidly on identification.
Reliance on veterinary surgeons
The surveillance route of the Gwaredu BVD programme is highly dependent on veterinary surgeons to both remember and encourage farmers to participate in the programme. Veterinary surgeons and the veterinary–farmer relationship are a vital part of this scheme. Maintaining veterinary engagement and enthusiasm for the scheme is essential. To help this Gwaredu BVD provides CPD online and in person to veterinary surgeons and support staff. The office is available for queries and more general support in both surveillance and eradication activities.
If legislation is put in place, Gwaredu BVD strongly hopes that similar support will be made available to veterinary surgeons and farmers.
Currently most testing takes place at the time of the bTB test. The use of bTB testers has recently been authorised and how BVD testing will be carried out on farms where these individuals carry out work is not yet clear.
Conclusion
Gwaredu BVD has developed a long way from the initial concepts suggested to various committees as the project team worked towards a funded application. The simple model, exploiting the already existing veterinary activities in Wales and building on and enhancing these has largely been accepted by the farming and veterinary industries. With 84% of farms in Wales testing once, it is appropriate that legislation is put in place to retain the gains, and allow Welsh farming to cement a reputation for sustainable high health production.