Welsh Bovine Viral Diarrhoea Eradication Scheme: guidance

We are committed to supporting an ambitious industry-led scheme to eradicate Bovine Viral Diarrhoea (BVD) from Wales.

From 1 July 2024 until 1 July 2025, no movement restrictions will be applied at herd level for herds that have a BVD antibody-positive test. 

We strongly recommend the appropriate actions described in the recommended testing options section below are undertaken before 1 July 2025. The aim is to clear the herd of BVD infection before herd movement restrictions are introduced in July 2025.

From 1 July 2024, all cattle herds are required to carry out antibody screening for BVD annually:

• samples must be submitted to an approved laboratory
• the result will be issued by the laboratory and will set the herd status to BVD Negative or Not Negative
• results will be reported by the laboratory to the keeper, their primary veterinary care provider, and the Welsh Government
• the herd status will be changed automatically by the BVD database system to BVD Negative, provided there are no BVD positive and BVD PI animals in the herd

Keepers of cattle herds in Wales must have their herds screened every year for BVD. 

You do not have to individually test every animal in the herd to find out if BVD is present. Instead, you will have to do an antibody screening test that will show if the herd has been exposed to BVD. The result of the screening test will tell you and your vet whether the herd is free of BVD. Or whether you need to do follow-up testing to find out if there is an active BVD infection in your herd. 

Your vet will be able to advise which animals to select for antibody testing. You must use one of the following methods:

Mandatory annual BVD antibody screening method:

Whenever possible for a screening test, use option (a) below. Where this is not possible options (b) and (c) should be followed in order. This test is for identifying antibodies and will determine if your herd has been exposed to BVD virus.

Before deciding to do a screening test, speak to your vet to identify how many separately managed groups you have in your herd. Your vet will decide how many animals need to be blood tested.

a) Five unvaccinated calves aged 9 to 18 months

Your vet should take samples of blood from not less than five unvaccinated calves in the age range of 9 to 18 months in each separately managed group. If there are fewer than five calves in a group, then test all the calves in the group.

b) Ten unvaccinated calves aged 0 - 9 months

If any of your sample of calves are aged 0-9 months, then your vet should take a sample of blood from not less than ten unvaccinated calves in the age range 0-9 months in each separately managed group. If there are fewer than ten calves in a group, then test all the calves in the group.

c) Five unvaccinated cattle over 18 months

If you have no calves in either of the above age categories, only then, can you choose to use the following method: 

Your vet should take a sample of blood from not less than five unvaccinated animals from each separately managed group. 

Recommended testing options:

a) Voluntary Calf testing

Individually test all newborn calves in the herd for virus by blood or tissue sample. You can test the calves as they are born or all at once. Ear tissue tag testing (explained below) can be a particularly useful way to do this and is the only method, that you may do without the assistance of a vet.

Ear tissue tags

Ear tissue sampling tags are designed to take a tissue sample from the ear whilst tagging the animal. The tissue goes into the labelled capsule when the animal is tagged, which you then snap off and send to the laboratory.

If you want to purchase ear tissue sampling tags, then contact your usual ear tag supplier. If they do not stock them, they should be able to direct you to somewhere that does. If you are sampling calves under 20 days old, you must use an official ID tag to take the BVD sample. This minimises the number of tags that are applied to a calf’s ear and reduces typographical errors at the BVD testing laboratory. Management tags can be used to take samples from other cattle (e.g. dead calves, older animals).

Important welfare note on ear tagging

If you wish to use tissue sampling tags you should minimise the number of tags applied to each animal. Applying additional ear tags can cause welfare problems for cattle.

If you decide to use tissue sampling tags, make sure you use the correct applicator. Some may appear to work with other tags but can apply them too tightly, causing pain and leading to infection.

b) Voluntary Whole herd antigen testing

Individually blood or tissue sample all the animals in the herd. This is a test for the BVD virus and has the advantage that all the persistently infected (PI) animals in the herd can be identified and removed. You may choose to tissue tag, in which case a vet does not need to be consulted, however, if you choose to take blood samples your vet will need to be involved. 

Cows that get infected with BVD in their first four months of pregnancy can give birth to a persistently infected (PI) calf. These PI animals are the major source of BVD infection, as they will have the virus all of their lives and spread it in huge quantities. They are born BVD Positive and remain so for the rest of their lives. Many will die within the first year of life, but some can live much longer and may appear normal. Cattle infected with BVD after birth are transiently infected and will normally recover in around three weeks but do suffer from a reduced ability to fight other infectious diseases and are likely to have impaired fertility until they recover.

Keepers can choose to retest a Positive animal to find out whether it is a PI or only a transiently infected animal. The retest must be done by a vet. It is best practice to remove BVD Positive and BVD PI animals from the herd as soon as possible. This can be done by culling on farm or sending the animal directly to an abattoir. BVD Positive animals are only permitted to move directly to an abattoir unless re-tested negative for BVD antigens after 21 days from the initial test.

Herds that have a BVD PI animal are classed as BVD Not Negative and their movements are restricted. Only BVD Negative animals can move out of the herd, as long as they have a valid BVD pre-movement antigen test result. 

From 1^st of July 2024, BVD PI animals will be restricted on the farm for life. They must be:

• housed indoors
• isolated from the rest of the herd with separate feed and bedding status 
• not give rise to any appreciable risk of spreading BVD 

It is strongly recommended that BVD PI animals are removed as soon as possible from the herd. 

BVD Herd status changes:

The mandatory annual antibody screening test or the identification of a PI animal in a herd are the only triggers for changing a herd’s BVD status from BVD Negative to BVD Not Negative. 

For the herd status to change from BVD Not Negative to BVD Negative, all cattle with a BVD Positive status must be resolved. All cattle with a BVD PI status must be removed from the herd.

Individual BVD animal status: 

Depending on the disease status an individual bovine animal can be:

• BVD Negative – this status applies to cattle which have had a negative antigen test result. This animal is exempt from future PI Hunts but will require a BVD pre-movement test to be moved out of the herd if the herd status is BVD Not Negative.
• BVD Positive – this status applies to cattle which have had a positive antigen test result. These animals can either be removed from the herd or re-tested for BVD antigens after 21 days from the initial positive antigen test.
• BVD PI – this status applies to cattle which have had two positive antigen test results in succession. These animals must be isolated from the rest of the herd for the remainder of their lives. It is strongly recommended to remove these animals from the herd as soon as practicably possible.
• BVD Unknown – this status applies to cattle which have not been individually tested for BVD under the Welsh BVD eradication scheme.

Movement restrictions 

Starting 1 July 2025, all Welsh cattle herds that have a herd BVD status of BVD Not Negative will be placed under movement restrictions.

A herd that is BVD Not Negative cannot move any cattle from the herd, without a valid negative BVD pre-movement antigen test. This negative BVD antigen test result will be valid for 30 calendar days from the date of sampling the animal. Herd movement restrictions apply from the time any BVD-positive antibodies are identified in a cattle herd during the annual mandatory BVD antibody screening.

• Keepers cannot move BVD Positive or BVD PI animals out of the herd except for slaughter.

Movement restrictions are lifted when:

• on retest, the BVD Positive animals have NOT been confirmed as a BVD PI, or
• the BVD Positive animal is removed to slaughter or killed on farm and,
• The evidence confirms that BVD has been eradicated from the herd.

BVD antigen pre-movement testing:

All BVD negative animals in BVD Not Negative herds will require a negative pre-movement antigen test (valid for 30 days from the taking of the sample) unless moving to slaughter or moving under a license granted by a veterinary inspector or Welsh Ministers.

If an animal tests positive at the pre-movement antigen test. The animal cannot be moved and will need to be re-tested after 21 days. The herd status will remain unchanged and the other animals in the herd do not need to be tested other than for pre-movement purposes.

Buying animals from outside of Wales: 

Keepers moving cattle with an unknown BVD status onto a Welsh holding will have to antigen test the animals within 20 days after the move. Animals with a BVD unknown status brought into a herd cannot leave the herd without an individual BVD Negative status.

If an animal tests positive upon post-movement, the herd status is amended to BVD not negative and the animal in question will need to be re-tested after 21 days. If the animal tests positive upon re-test it is classed as a “PI” and must be isolated.

In-calf cattle:

Keepers buying in-calf cattle must isolate them until they calve unless tested negative for BVD antigens and come from a BVD Negative herd.

Calf testing in BVD Not Negative Herds:

Keepers must antigen test within 20 days of birth all calves born in the 12 months following the detection of BVD antibodies.

Testing of Aborted or stillborn calves:

Aborted or stillborn calves must be tested within 7 days as far as reasonably practical. This requirement has no impact on the herd’s BVD status. It is used to gather evidence to support your veterinarian give you the best possible advice on eradicating BVD from your herd.

Informed Purchasing - Notification of BVD status before movement 

Keepers must disclose the BVD herd status and the individual animal BVD status before the movement takes place.

Keepers have to give notice within 72 hours prior to the movement/sale of cattle via the online system before move/sale to persons where the animal is being moved to. E.g. operator of a market, prospective keeper of the animal, any person with whom the animal is to be temporarily placed.

The use of an official tag for tissue tagging

If a calf is tissue tagged under 20 days old, the tag used must be one of the calf’s official tags.

Retest of a BVD Positive animal

A retest sample of a BVD Positive animal must be taken by a vet.

Reporting of test results

Test results must be reported and uploaded to the BVD database within 5 days of laboratory testing.

Under the Bovine Viral Diarrhoea (Wales) Order 2024, samples submitted for testing as a mandatory annual screening test must be sent to a laboratory approved by the Welsh Government for that purpose.

To submit a sample to an approved laboratory, please use a form provided by them.

• Agri-food and Biosciences Institute
• Axiom Veterinary Laboratories Ltd
• Biobest
• Farmlab Diagnostics
• National Milk Laboratories
• SRUC
• The Cattle Information Services (CIS)
• Welsh Veterinary Science Centre

Laboratory approval

To gain approval, a laboratory must:

1.     Hold a current accreditation of ISO17025 from an organisation that is itself accredited to ISO 17011 (EN 45002/3) for testing for BVD antigen and/or antibody.

2.     Be located in the UK or European Union.

3.     Agree to meet the duties of approved laboratories as described below.

Duties on approved laboratories

The laboratory must test samples submitted under the Order within five working days of receiving the samples.

The laboratory must declare a result for the samples submitted. This will be based on the test results generated by the samples submitted. The status will be either:

• negative for evidence of BVDV infection
• positive for evidence of BVDV infection or,
• unsuitable/insufficient test result where no result could be determined

Laboratories will use their professional judgment in reaching a decision on test results. They may request such information as they reasonably require of the person submitting the samples in order to reach a test result. Where insufficient information is supplied in spite of such a request being made, the laboratory may withhold a test result.

The laboratory must inform the keeper, the person submitting the samples and Welsh Ministers of the test results.

Laboratories may charge their customers at whatever level they decide, and at different levels for different types of tests. Fee levels for all types of tests should be published on the laboratory’s website.

Laboratories must electronically submit the individual official cattle ID numbers for each animal tested, the test type, the result from each sample and any other information required by the BVDCymru system.

Cattle that test positive will be classed as BVD Positive and can be re-tested by a vet after 21 days from the initial test. Cattle that test positive for BVD antigens twice in succession will be classed as BVD PI. BVD PI animals are restricted on farm for life and have to be isolated from the rest of the herd.

Laboratories must keep records for at least three years. The Welsh Government may request access for themselves or specify that it be given to research providers on their behalf.

Bovine viral diarrhoea: standard submission forms must be used for all BVD tests.

Laboratories must liaise with the BVDCymru service desk to promptly resolve test result submission errors.

Laboratories must adhere to the BVDCymru BVD result upload guidance when submitting their test submissions.

Livestock markets have an important part to play in the Wales BVD eradication programme. All cattle keepers, including temporary keepers such as auction marts, should inform potential buyers of the BVD status of their herd or the individual animal. Providing accurate information at the time of sale also helps to avoid disappointment and disputes when buyers take the animals home. Many sellers see the advantage of providing BVD information at all sales: full disclosure allows buyers to make arrangements to test BVD Not Negative animals, such as untested English stores, before mixing them with their existing herd.

BVD PI animals can only be moved directly to an abattoir. They cannot be moved through a market or to any other holding.  

When selling in-calf females, remember that the BVD status only applies to the dam. The status of the unborn calf cannot be guaranteed: calves can only be tested after birth and may have a different status to their dam. The best advice is for buyers to use a BVD tissue tag to identify the calf when it is born. 

Restrictions on the movement of animals off a holding with a BVD Not Negative herd status, a BVD positive animal or a BVD PI animal

All BVD negative animals in BVD Not Negative herds will require a negative pre-movement antigen test (valid for 30 days from the taking of the sample). Unless moving to slaughter or moving under a licence granted by a veterinary inspector or Welsh Ministers. 

If an animal tests positive at the pre-movement antigen test. The animal cannot be moved and will need to be re-tested after 21 days. The herd status will remain unchanged and the other animals in the herd do not need to be tested. 

Notification of BVD status prior to movement 

Keepers must give notice within 72 hours before the movement of animals via the online system to persons where the animal is being moved to e.g: 

• the operator of a market
• the prospective keeper of the animal
• any person with whom the animal is to be temporarily placed.

Some of the information you provide on the standard laboratory submission form will amount to your personal data. Welsh Government will be the controller for this information, and we will process it in line with our public task and the official authority vested in us. 

We will use your data to:

Accurately produce epidemiological reports and any relevant findings to better understand the incidence and prevalence of BVD in Wales, and; 

Produce maps showcasing the current disease status in Wales. 

These reports, findings and maps will be used by Welsh Government as part of the monitoring and evaluating step of the policymaking cycle. Should there be a need to share the epidemiological reports, findings and maps with 3rd parties, the personal data will be anonymised. 

Inform the data subject of its herd disease status. For this purpose, the personal data collected will be shared with:

• the laboratory processing the test samples – to be able to maintain continuity of evidence for the purposes of reporting disease status and analysing and interpreting epidemiological data.
• the veterinary surgeon collecting the test samples.

Send notifications to the data owner regarding the disease status of their herd, advice and support, next steps in the testing lifecycle, how to regain disease-free status, and how to maintain disease-free status.

For the purposes of disease monitoring and surveillance, for ensuring disease is diagnosed without undue delay and legislation is enforced and delivered, personal data will be collected by Welsh Government.

Your data will be retained for up to 15 years in line with the statutory requirements of The Bovine Viral Diarrhoea (Wales) Order 2024. This is a statutory requirement so data will be securely kept in order to monitor the progress of the scheme. We will keep this requirement under regular review.

You have the following rights:

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

The contact details for the ICO are as follows:

Information Commissioner's Office
Wycliffe House
Water Lane
Wilmslow
Cheshire
SK9 5AF

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

Data Protection Officer 
Welsh Government
Cathays Park
CARDIFF
CF10 3NQ

Email: DataProtectionOfficer@gov.wales