Is a 3 metre gap between my herd and neighbouring herds essential?
For the BVD accreditation programme this is a requirement however for the BVD vaccinated monitored free programme the gap is not essential however the breeding herd must be vaccinated against BVD virus. It is also worth considering grazing lower risk animals in the fields adjacent to neighbouring herds e.g. youngstock rather than the higher risk pregnant animals.
BVD Testing
What cattle do I need to test?
Five blood samples per group aged 9-18 months (or if sold before 9 months old then 10 samples per group down to six months old). Any non-homebred animals that have not been in contact with the youngstock groups must be blood tested for antibody and antigen/virus in addition.
Can I include bought-in animals?
These can be tested over and above the homebred youngstock screen. Any non-homebred animals that have not been in contact with the youngstock groups must be blood tested for antibody and antigen/virus.
I don’t have any cattle aged 9-18 months old – can I test other ages instead?
If sold before 9 months old then 10 samples can be collected per group down to six months old. Alternatively all calves born into the herd (including aborted and stillborn calves) can be tested for antigen/virus e.g. using ear tissue collected using the specially designed ear tags or on blood samples.
What is the difference between antibody and antigen?
Antibodies are produced by the immune system following exposure to the virus whereas antigen is part of the virus and is often used interchangeably with virus. PI animals are carriers of antigen/virus.
Do I test for antibody or antigen?
For the youngstock check test (five per group aged 9-18 months old) it is antibody testing. The alternative is to test all calves born into the herd (including abortions & stillbirths) using blood or ear tissue for BVD antigen (virus).
Bought-in cattle should be tested for both BVD antibody and antigen.
Can ear tissue test results be used to gain status?
As an alternative to testing a subsample of homebred young stock all calves born into the herd (including aborted and stillborn calves) can be tested for antigen/virus e.g. using ear tissue collected with the specially designed tags
How long can ear tissue samples be stored for before I need to send them to the lab for testing?
Samples can be stored in a cool, dark place for up to two weeks
How quickly can my herd gain BVD free status?
Two clear screens of consecutive calf crops are required and these would usually be done about 12 months apart.
My herd has passed its first qualifying test – when can I do the second qualifying test?
Once the next calf crop has reached nine months old. If testing all calves born into the herd for antigen/virus then continue testing all calves that are born until two years of calves have been tested.
What testing is required for the second herd test?
The same testing is done as for the first test i.e. five homebred cattle from each group aged 9-18 months old (or ten per group if 6-9 months old). If testing all calves born into the herd for antigen/virus then continue testing all calves that are born until two years of calves have been tested.
Once I have gained status for my herd do I need to test every year?
Yes, the same testing is required each year. Herds can switch from a complete calf screen for antigen/virus to an antibody check test i.e. five homebred cattle from each group aged 9-18 months old (or ten per group if 6-9 months old)
Which cattle do I test for the annual herd test?
The same testing is done as for the qualifying tests i.e. five homebred cattle from each group aged 9-18 months old (or ten per group if 6-9 months old) or testing all calves born into the herd.
I want to find the PIs in my herd – do I need to test all cattle?
If the herd has good records then it may not be necessary to test all of the cows. A PI cow will always produce a PI calf so if the calf is not a PI its dam will not be a PI. Any cows that do not have an offspring that can be tested will need to be sampled e.g. barren/aborted or if its calf has died. All youngstock up to calving age plus any males would need to be sampled.
Once I have removed the PI animals from my herd what is the next step?
Continue testing all calves born into the herd (for antigen/virus) for 12 months from when the last PI was removed.
Can my test results be forwarded to the central BVD database (e.g. BVD Free England, Scottish Government/ScotEID)?
Yes results can be uploaded to a central databases. A small charge is incurred for uploading BVD Free England results to their database which is passed on to the member.
There is no charge for uploading BVD accredited status to the BVD Free England website
BVD Vaccination
What does BVD Vaccinated Monitored Free status mean?
The herd has had two clear calf crop screens and the breeding herd is being vaccinated against BVD virus. There is no requirement for a minimum 3 metre gap between neighbouring herds so it is of a lower health status than BVD accredited free status. The BVD VMF programme is therefore more suitable for herds that are not selling replacement breeding stock.
My herd is vaccinated against BVD – can I still gain status?
Yes vaccine can be used in the accreditation programme and it is essential for breeding cattle if participating in the BVD Vaccinated Monitored Free programme
Will the use of BVD vaccine in my herd interfere with testing?
It is still possible to identify PI animals if BVD vaccine has been used in a herd. Vaccination will generate antibodies which may be detectable in the BVD antibody blood test so when carrying out the youngstock check test they should be blood sampled before being vaccinated.
I have bought-in cattle in my herd and don’t know their vaccination status. Can they be tested for BVD?
Yes, they should still be tested for both BVD antibody and antigen. It is still possible to identify if they are PI animals.
Can I use vaccine to protect animals going to shows?
Yes this is worth considering. Some shows are now insisting that all cattle are tested for antigen/virus before being allowed entry to the show, which will reduce the risk of them coming into contact with the virus. However there is a risk that cattle could be transiently infected with BVD virus i.e. if they are exposed to the virus in the week to ten days before the show. Naïve animals that come into contact with them could be at risk of infection and could take virus back to their home herd. A quarantine period after showing would prevent this. Pregnant animals would be at greatest risk as a PI calf could be created in the womb if the cow/heifer is in the first 120 days of pregnancy.
BVD - Added Animals
What testing is required for bought-in animals?
Unless bought-in animals are being added direct (i.e. not through a market) from a BVD accredited herd (in which case testing is optional) then:
Test for BVD antibody and antigen/virus at least 28 days after entry to quarantine (an earlier additional test can be carried out if desired but must be repeated at this stage). If all animals are antibody and antigen negative they can be released from quarantine.
If a group of animals has mixed antibody positive and negative results the group should remain in quarantine and the antibody negative animals should be retested after at least a further 28 days. If the negatives remain negative the group can be released from quarantine.
If pregnant animals are antibody positive they should be kept isolated from the herd until the calf is born and can be tested for virus/antigen as there is a risk that they could be carrying a PI. If known to be antibody positive or fully vaccinated prior to service they can be removed from quarantine but the calf should still be tested for virus when it is born.
I have purchased in-calf female replacements – can they be added to the herd if they test negative for virus after being in quarantine?
If they are antibody negative then yes. However if pregnant animals are antibody positive they should be kept isolated from the herd until the calf is born and can be tested for virus/antigen as there is a risk that they could be carrying a PI. If known to be antibody positive or fully vaccinated prior to service they can be removed from quarantine but the calf should still be tested for virus when it is born.
What testing is required for animals returning from show/sale?
Test for BVD antibody and antigen/virus at least 28 days after entry to quarantine. If all animals are antibody and antigen negative they can be released from quarantine.
If a group of animals has mixed antibody positive and negative results the group should remain in quarantine and the antibody negative animals should be retested after 28 days. If they have all remained antibody negative the group can be released from quarantine.
If pregnant animals are antibody positive they should be kept isolated from the herd until the calf is born and can be tested for virus/antigen. If known to be antibody positive pre-showing or fully vaccinated prior to service they can be removed from quarantine but the calf should still be tested for virus when it is born.
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