Preventing the Spread of BVD During Calving Season

The longer a BVD-positive (BVD+) calf remains on the farm, the greater the risk of infection spreading, both within the herd and to neighbouring farms.

• Tag all newborn calves as soon as possible after birth. Ensure that calves are dry before tagging to minimise the occurrence of ‘empty’ tags (tags without tissue samples).
• Isolate newborn calves from pregnant cows and maintain strict biosecurity measures until a negative test result is confirmed.
• Farmers participating in the National Genotyping Programme will receive double tissue tags. Note that BVD sampling under this scheme requires a different set of taggers. BVD sample bottles/vials and lab envelopes are white, while DNA sample bottles/vials and lab envelopes are pink. Ensure each sample type is sent to the correct laboratory.

Send samples to the testing laboratory as soon as possible after collection.

• Place samples in a sealable bag inside a padded envelope.
• Clearly write your name, address, and herd number in the top left-hand corner of the envelope.
• Mark the envelope with ‘Exempt Animal Specimen’ on the back.
• Currently, the minimum postal fee for sending samples to a laboratory in Ireland or Northern Ireland is €2.95, which covers up to 10 samples if packed flat. For larger submissions, visit the post office to ensure correct postage.

If a tissue tag test returns a positive or inconclusive result:

• Isolate the affected calves immediately and remove them as soon as possible.
• Prompt removal is essential to qualify for higher financial support from the Department of Agriculture, Food and the Marine (DAFM) and to reduce the risk of further spread within the herd.
• Confirmatory testing of positive or inconclusive animals is no longer allowed.

Herds located near an infected herd are at a higher risk of contracting BVD.

• Research indicates that breeding herds within 400 metres of a BVD+ herd have a one in seven chance of testing positive the following year.
• Herds near farms that had BVD+ calves in 2024 (those within or adjacent to the highlighted hexagons in Figure 1) are particularly vulnerable.
• These herds should prioritise prompt tagging and testing, as well as reviewing biosecurity measures to quickly identify and isolate any BVD+ calves, preventing further spread (see next section).
• Check your area on the provided map to assess potential risks.