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1. Bovine Viral Diarrhoea (BVD) is a viral infection of cattle, which can cause a variety of health issues, including abortion, infertility, and Mucosal Disease which is fatal. BVD in herds is maintained by a small population of animals that become “Persistently Infected” (PI) with the virus.

2. PI animals become infected with the virus in the uterus during early pregnancy. A PI animal may appear healthy but will remain infected for its entire life and infect others in the herd. It is likely 1-2% of animals in infected herds are PIs.

3. The presence of just one PI animal in a herd can quickly spread the virus and have a significant financial impact. The estimated annual costs of BVD presence to a 100-cow beef farm is £4,500 and for a 130-cow dairy farm, £15,000 a year. The removal of the PI animals is essential to eradicating the disease at farm level.

4. A PI animal has a high likelihood of suffering from poor health and diminished productivity throughout its life, lowering its market value and presenting welfare issues. A significant number of PIs will also die before reaching slaughter weight, due to a suppressed immune system.

5. Gwaredu BVD operates a voluntary BVD screening service for Welsh cattle keepers, funded by the Welsh Government through Rural Payments Wales. They can also assist keepers in identifying PI animals within a herd and provide guidance on achieving BVD freedom. Funding from Rural Payments Wales will no longer be available from 1 January 2023 bringing the voluntary BVD scheme to an end.

6. There are approximately 11,000 cattle herds in Wales. To date, around 9,163 of these herds have been screened for BVD (approximately 83.3%) and 2,539 (28%) of this figure tested positive for the virus. Within those herds, 940 PI animals have been identified.

7. Data gathered during the voluntary phase of the Gwaredu BVD scheme has shown it has not been possible to ensure PI removal from farms and BVD eradication through a voluntary scheme. This is because there are no restrictions on the movement of PI animals or their herd. Management of PI animals in Wales has been inconsistent, with some keepers choosing to retain or sell these animals on.

8. Vaccination is available for BVD, but this does not represent an effective way to eradicate the disease, as PI animals cannot be vaccinated and are incapable of building immunity to the disease. They continue to shed virus and present a constant infection risk in herds.

9. Cattle can become infected with BVD from:

  • nose-to-nose contact with infected cattle
  • transmission in the uterus from a pregnant, infected dam (making the calf a PI)
  • sexually via infected semen
  • contact with contaminated fomites (objects or materials which can carry infection, such as clothes or vehicles)

10. It is important to note that only animals infected in the uterus become PIs. Animals infected otherwise will not remain infected permanently.

11. BVD is an “immuno-suppressive” disease, which means infected animals become more likely to get other infections and this can have a serious impact on the general health and welfare of cattle.

12. BVD also affects the production in a cattle herd; it can cause a loss of milk yield and reduced appetite in cattle and result in a less efficient farm. This leads to financial losses for keepers and can increase cases of anti-microbial resistance (AMR).

13. The current voluntary scheme was launched in 2017 and has been extended until 31 December 2022. The screening is undertaken at the same time as testing for Bovine Tuberculosis (TB) in the form of a blood antibody test from 5 unvaccinated stock between 9 and 18 months old.

14. If the BVD screening returns an antibody negative status, it will signify there has been no BVD infection within the herd. An antibody positive status will confirm BVD infection is or has been present in the herd. It’s possible a PI animal is the cause of infection within an antibody positive herd.

15. Gwaredu BVD currently provides advice for herds that test positive for BVD and up to £1,000 to conduct a PI animal hunt, using additional testing methods to determine active infection with BVD in an animal.

Proposal for a compulsory BVD scheme

Annual herd screening

16. The Welsh Government’s intention is to replace the voluntary BVD scheme with a compulsory scheme, underpinned by legislation. This legislation will require all cattle keepers to have their herds annually screened for the virus, beginning with a BVD screening within 12 months of their previous voluntary screening, to be completed by an approved veterinary surgeon.

17. Screening would be done by blood sampling 5 animals per management group (a group of animals kept separate from other groups on the premises) in the 9-18 months age group. Where such animals are not present on the farm then 5 animals from other age groups would be permitted. If animals younger than 6 months are sampled, then 10 animals per management group should be sampled. This is to ensure a good sample is taken from a group, which may have had less exposure to any virus present in the herd.

18. Samples would then be sent by the veterinary surgeon to an approved laboratory for testing. The results of the screening will determine the “Herd Status”. Herds with negative BVD status will maintain this status for 12 months and no restrictions will apply to their cattle movements.

Positive Herd Status and PI Hunt

19. Positive herd status will be assigned when any animal tested as part of the screening process returns a positive result for BVD antibodies. 

20. Herds that test positive for BVD antibodies will have their movement restricted and all animals in the herd will be required to be individually tested, including those born in the 12 months after the positive screening test. Animals that return a positive BVD antigen test will require an additional test after 21 days have passed, to determine whether the animal has developed immunity.

21. This further antigen testing will aim to identify any PI animals and is known as a “PI hunt”. A PI animal can be identified, as it will return consistent positive BVD results throughout its lifetime and will never develop immunity to the virus. This is proved by repeating the antigen test from a BVD positive animal 21 days after its original test. This would be sufficient time for a non-PI animal to develop immunity to the disease.

22. Individual cattle from an antibody positive herd that test positive will only be allowed to move to slaughter unless they have returned a subsequent negative BVD antigen test and 21 days have passed. This will not be possible for a PI animal, given its inability to achieve immunity.

23. Individual cattle from an antibody positive herd that test negative, either during initial screening or following additional tests will be required to complete a premovement test in the form of a negative antigen test 21 days prior to any movement from the herd they are based in.

24. Keepers, whose herds receive a positive BVD herd status, will be encouraged to agree an animal health plan with their private vet on how to manage the BVD risks on their holding in line with Government guidance.

25. If a PI animal is identified, the keeper will be required to isolate the animal indefinitely from the rest of the herd. Isolating the animal requires keeping it in a separate enclosure than the rest of the herd or neighbouring cattle, in an environment sufficient to maintain the animal’s welfare and normal behaviour.

26. Isolation may include the need for single PI animals to be isolated together with companion animals from the herd in order to maintain their welfare and social interaction.

27. To ensure the welfare of any companion animals is maintained, as a minimum, two companion bovine animals should be housed with the PI during its period of isolation. This is to ensure their relationships are not negatively impacted by prolonged separation from the rest of the herd and they are able to maintain a bond with one or more other animals from the herd once the PI has died or been sent to slaughter.

28. In order to reduce the risk of onward spread of BVD, the companion animals should not be animals ever intended for breeding during or following isolation, as contact with a PI animal will present an increased risk of producing more PIs if used for breeding after serving as a companion animal.

29. Once the isolated PI has been moved to slaughter or has died naturally, the companion animals should be tested for BVD infection via antigen test and should return a negative result before being re-introduced to the herd. If a positive result is returned, further testing should be undertaken after 21 days has passed to ensure the animals no longer present a disease risk.

30. This is to prevent the spread of BVD to the rest of the herd. This measure must then remain in place until the PI animal is slaughtered or dies naturally. Identified PI animals will not be allowed to be sold or otherwise moved off the farm, unless to slaughter.

31. Milk and meat from a BVD infected animal, however, can be entered into the food chain as BVD does not present a risk to human health.

32. Any herd that does not participate in a BVD screening within the 12 month window will be subject to the same requirements as a herd that tests positive for BVD antibodies.

33. The aim of the compulsory BVD scheme will be to achieve BVD freedom in Welsh cattle herds. The benefits of eradicating BVD in Wales are:

  • the improved general health and welfare of Welsh cattle
  • increased efficiency and profitability of Welsh cattle farms
  • improved trade prospects for Welsh cattle keepers within the UK and with Third Countries
  • cattle keepers will be able to show potential buyers their herd’s and individual animal’s health status and freedom from BVD
  • potential for reduced greenhouse gas emissions and carbon footprint, due to more efficient farming
  • reduced demand for medicinal treatment for cattle and reduction in anti-microbial resistance (AMR)
  • Alignment with other UK countries, which either have established or are developing their own eradication schemes.

Transition period

34.The full implementation of the compulsory scheme may be preceded by a 3 to 6 month transition period, during which, cattle may only be moved from holdings that hold an antibody negative status for BVD, obtained during the voluntary phase. Herds that test positive for BVD antibodies will require additional pre-movement testing of individual animals before they can be moved off farm unless that movement is to slaughter. The intended purpose of the transitional phase is to give keepers sufficient time to arrange BVD screens for their herds and remain compliant with scheme requirements.


35. In order to gather views on this proposed legislation, the Welsh Government has issued this consultation, which will allow participants to respond to individual aspects of the proposal. Responses to the consultation will be collated and reviewed by Welsh Government officials and a summary will be published.

36. This consultation commences on 30 June 2022 and will close on 25 August 2022

37. The responses received will be carefully considered against the proposal for BVD legislation and, if considered beneficial, may help shape or amend the proposal.

38. The intention of the consultation is to use the insight of Welsh cattle keepers, industry, and other stakeholders to make the proposal more suitable, fair and accessible to those subject to its requirements.

39. The questions below will ask for your views on the introduction of mandatory BVD testing and the details of this proposal.

Consultation questions

Bovine Viral Diarrhoea (BVD) eradication

The Welsh Government believes eradicating BVD will bring significant animal welfare and economic benefits to keepers and their animals, as well as trade for Wales within the UK and with Third Countries. There are also wider benefits to achieving BVD freedom, including the increased efficiency and reduced carbon footprint of Welsh farms and supporting the campaign against anti-microbial resistance (AMR). The introduction of BVD legislation would be consistent with efforts in England, Scotland, Northern Ireland, and the Republic of Ireland, which either have or are planning to introduce their own compulsory schemes. The introduction of successful eradication schemes by individual administrations will help eradicate the disease from the UK more effectively, with consistent measures and aims.

Question 1

Do you agree that BVD presents a problem for the farming industry in Wales?

Question 2

Do you agree that BVD eradication will improve the health and welfare of Welsh cattle?

Question 3

Do you agree that eradication of Bovine Viral Diarrhoea (BVD) will benefit Welsh cattle keepers?

Question 4

Do you agree with the introduction of legislation to support the eradication of BVD from Wales?

BVD Screening

All herds will be required to have an annual screen for BVD (as detailed in the description of the voluntary phase) completed no later than 12 months after any previous screen.

The screening will take the form of a blood test sample taken from the animal(s)by an approved private veterinary surgeon and sent to an approved laboratory for testing.

This will give a “Herd status” that will be shared with the keeper by the private vet and renewed annually.

In Herds with negative BVD status, cattle will not be subject to BVD movement restrictions or individual testing.

In Herds with positive BVD status, all animals will be individually tested, including those born in the 12 months after the positive screening test. Animals that return a positive BVD antigen test will require an additional test after 21 days have passed, to determine whether the animal has developed immunity.

Furthermore, all animals in a BVD positive herd will be subject to the following movement restrictions:

  • Antigen positive (PI) animals will only by allowed to move to slaughter.
  • Antigen negative animals (animals which test negative at screening or following additional testing) will only be allowed to move from the holding where they are based if they have received a negative antigen test 21 days prior to movement. The 21 day period of testing before movement is based on scientific and veterinary advice.

Herds, which fail to test within the 12 months will be treated as if they have tested positive and will be subject to the movement restrictions above.

Question 5

Do you agree that legislation imposing requirements for mandatory regular BVD screening is necessary to eradicate the disease? 

Question 6

Do you agree that cattle from a herd with positive BVD status, that test positive, should have their movement restricted, unless that movement is to slaughter?

Question 7

Do you agree that cattle from a herd with positive BVD status, that test negative for BVD via antigen test, should not be permitted to leave the holding where they are based unless they obtain a pre-movement negative antigen test within 21 days of the move?

Question 8

Cattle keepers may be required to pay for their herd screenings, PI hunts and pre-movement testing to move cattle from a BVD positive herd. Do you agree that, in principle this is a fair expectation?

PI management and isolation

BVD in herds is maintained by a small population of animals that become “Persistently Infected” (PI) with the virus. PI animals become infected with the virus in the uterus during early pregnancy. A PI may appear healthy but will remain infected for its entire life and infect other animals in the herd.

By identifying a PI animal and isolating it from other animals for its lifetime, the potential for animals in the herd and neighbouring herds becoming infected will be greatly reduced.

The keeper may either maintain the PI animal in isolation until it dies naturally or send the animal to slaughter. Once all identified PIs in a herd have either died naturally or have been slaughtered and effective movement restrictions prevent BVD being reintroduced, the herd will achieve “BVD freedom”.

If keepers choose to keep a PI animal, they will be advised to agree an Animal Health Plan with their private vet, which includes specific considerations for effective PI isolation on their holding, in line with Government guidance, which would be issued alongside legislation.

This may include keeping single PI animals in isolation together with a minimum of two non-PI companion animals from the herd to ensure their welfare (to note, companion animals should not be intended for breeding, in order to reduce the risk of BVD spread).

It has not been possible to ensure effective management of PI animals through a voluntary scheme. However, the Welsh Government believes progress towards BVD freedom can be achieved in Wales through legislation to ensure effective isolation and removal of PI animals from herds.

Question 9

Do you agree that legislation imposing requirements for mandatory PI isolation is necessary to eradicate the disease?

BVD Data Management

The following data may be collected by or on behalf of Welsh Government in relation to BVD screening and testing:

  • Name and contact details of the keeper
  • The address, name and type of business (e.g. cattle/dairy farm)
  • BVD antibody herd status and dates of previous screenings
  • BVD antigen test results for individual animals
  • Animals identified as persistently infected (PI) within the herd
  • Information regarding instances of non-compliance with scheme requirements

It is proposed, that herd BVD status and antigen results of individual animals will be made accessible to other cattle keepers via their EIDCymru login on the online Welsh Government Multi Species Wales portal.

This will enable keepers buying cattle to view the BVD status of a herd they are buying from (i.e., whether animals in that herd have returned positive results for BVD antibodies at the screening stage). This will ensure keepers are aware if they are buying from a BVD positive herd. They will also be able to view the individual antigen status of the animal they are purchasing.

The level of BVD information displayed to keepers will be kept at a minimum to allow the practice of informed purchasing to operate. No personal or sensitive information, or information related to non-compliance with the scheme will be shared.

By ensuring relevant BVD information is available for keepers, awareness and responsible purchasing will reduce the spread of the virus and movement of infected animals will also be greatly reduced. This will allow keepers to protect their herds and their farm revenues by ensuring only healthy animals are brought into their herds and the risk to their businesses is lower.

All information will be stored and accessed securely to protect the data usage rights of keepers.

Question 10

Do you agree that farms should have the BVD status of their herds and individual animals (where their herd status is BVD positive) made securely available to other keepers via the Multi Species Wales online portal at the time of purchasing cattle?


It is intended that failure to comply with the compulsory scheme will be an offence under the Animal Health Act 1981.This is to ensure Welsh cattle herds are appropriately and regularly screened for BVD and that untested or BVD positive animals are not moved for sale. The intention is that cattle keepers will be expected to maintain compliance with the compulsory scheme requirements and to manage the BVD risks on their farms effectively. The proposed offences would include:

  1. Not antibody screening young stock within the permitted timescale
  2. Moving stock from a positive herd without an antigen test
  3. Not isolating an animal that has tested positive at antigen test

It is proposed that local authorities will be empowered to enforce all parts of the legislation including powers of entry (i.e. visiting farms), and we would expect them to act proportionately in accordance with their normal enforcement policy.

It is proposed that penalties would be applied in accordance with the Animal Health Act 1981 and could include an unlimited fine or imprisonment.

Question 11

Do you agree keepers that breach the requirements of the proposed compulsory scheme should be liable to penalties?

Question 12

Are you involved with cattle keeping?

Question 13

We would like to know your views on the effects that a BVD eradication scheme for Wales would have on the Welsh language, specifically on opportunities for people to use Welsh and on treating the Welsh language no less favourably than English.

What effects do you think there would be? How could positive effects be increased, or negative effects be mitigated?

Question 14

Please also explain how you believe the proposed policy could be formulated or changed so as to have positive effects or increased positive effects on opportunities for people to use the Welsh language and on treating the Welsh language no less favourably than the English language, and no adverse effects on opportunities for people to use the Welsh language and on treating the Welsh language no less favourably than the English language.

Question 15

We have asked a number of specific questions. If you have any related issues which we have not specifically addressed, please use this space to report them.

How to respond

Submit your comments by 25 August 2022, in any of the following ways:

Your rights

UK General Data Protection Regulation (UK GDPR)

The Welsh Government will be data controller for any personal data you provide as part of your response to the consultation. Welsh Ministers have statutory powers they will rely on to process this personal data which will enable them to make informed decisions about how they exercise their public functions. Any response you send us will be seen in full by Welsh Government staff dealing with the issues which this consultation is about or planning future consultations. Where the Welsh Government undertakes further analysis of consultation responses then this work may be commissioned to be carried out by an accredited third party (e.g. a research organisation or a consultancy company). Any such work will only be undertaken under contract. Welsh Government’s standard terms and conditions for such contracts set out strict requirements for the processing and safekeeping of personal data.

In order to show that the consultation was carried out properly, the Welsh Government intends to publish a summary of the responses to this document. We may also publish responses in full. Normally, the name and address (or part of the address) of the person or organisation who sent the response are published with the response. If you do not want your name or address published, please tell us this in writing when you send your response. We will then redact them before publishing.

You should also be aware of our responsibilities under Freedom of Information legislation If your details are published as part of the consultation response then these published reports will be retained indefinitely. Any of your data held otherwise by Welsh Government will be kept for no more than 3 years.

Your rights

Under the data protection legislation, you have the right:

  • to be informed of the personal data held about you and to access it
  • to require us to rectify inaccuracies in that data
  • to (in certain circumstances) object to or restrict processing
  • for (in certain circumstances) your data to be ‘erased’
  • to (in certain circumstances) data portability
  • to lodge a complaint with the Information Commissioner’s Office (ICO) who is our independent regulator for data protection.

For further details about the information the Welsh Government holds and its use, or if you want to exercise your rights under the UK GDPR, please see contact details below:

Data Protection Officer

Welsh Government
Cathays Park
CF10 3NQ

Rydym yn croesawu gohebiaeth yn Gymraeg / We welcome correspondence in Welsh.

Information Commissioner’s Office

Wycliffe House
Water Lane

Telephone: 01625 545 745 or 0303 123 1113

Rydym yn croesawu galwadau yn Gymraeg / We welcome calls in Welsh.



  1. Bovine Viral Diarrhoea (BVD) – An immunosuppressive disease of cattle
  2. Immunosuppressive disease – A disease that reduces the immune response of the infected animal
  3. Cattle keeper – The owner or person responsible for the cattle.
  4. Persistently infected (PI) animal – An animal that has become infected with BVD in the uterus during pregnancy and remains infectious for its lifetime
  5. Management group – Any group of animals kept separate from other animals on a premises.
  6. Antibody test – A test to determine if an animal has produced antibodies against a specific viral infection (i.e. has the animal been previously infected). This can be done via blood sampling, tissue and tag testing or (for dairy farms) via bulk milk sampling.
  7. Antigen test – A test to determine if an animal is currently infected with a virus
  8. PI Hunt – The measure by which additional BVD antigen testing takes place on a farm to identify infected and persistently infected (PI) animals
  9. Gwaredu BVD – An industry-led scheme, funded by Welsh Government, which facilitates on-farm BVD testing
  10. Herd status – A designation of whether BVD is present in a herd or not.

Number: WG45481