It is 13 years since a voluntary control programme for bovine viral diarrhoea (BVD) was introduced in NI and over 10 years since the compulsory phase was put in place.

Since then, farmers have had to tissue sample all newborn calves.

That comes at a cost beyond the extra expense of the tag, whether it is time spent gathering samples and then taking them to a post office or your local tag supplier.

But even if we just concentrate on the extra cost of the tissue tag, a conservative estimate would suggest NI farmers have spent well over £20m on BVD tagging and testing since 2016 – if that figure had been known at the time, it would not have been believed.

That said, there is no doubt significant progress has been made and we have a much healthier cattle herd as a result of the BVD programme. But this disease should have been eradicated within five years and the reason it still exists is principally down to the actions of a small group of people who retain cattle persistently infected (PI) with BVD.

With many farmers no longer vaccinating and with fewer PI’s overall, we have a NI herd that is increasingly naïve to the disease – exposure to a PI can have potentially devastating results.

Controls

Since February 2025, the department has gradually introduced tighter controls on herds with PI calves and there is now an immediate movement restriction put on a herd with a positive or inconclusive BVD result. These restrictions are necessary to increase the pressure on those who don’t follow the rules, but inevitably will also catch out innocent farmers.

Unfortunately, more probably still needs to be done, especially where farmers request a re-test of a calf which give an initial positive result.

Perhaps the solution is that participation in the bovine genetics programme is made compulsory (rather than voluntary) in 2027, so all calves will be DNA sampled – if a BVD re-test is being done, the calf just has to be sampled again to prove it is the same animal.

Or alternatively, we can just keep spending over £2m every year on tissue tags.