The number of calves with an initial bovine viral diarrhoea-positive (BVD) or inconclusive result is running at over twice the level for the corresponding period in 2024.

New data published by Animal Health Ireland (AHI) for the first 12 weeks of 2025 shows 212 calves with an initial positive or inconclusive result without a negative retest result – twice the figure of 102 BVD-positive calves in the corresponding period in 2024.

This higher incidence is occurring despite the number of calves tested to date in 2025 – at 953,796 head – running 66,943 lower than in 2024. The incidence of BVD-positive calves in 2024 was at its lowest level since the eradication programme began, finishing the year with just 444 BVD animals compared to 625 head in 2023.

The AHI data suggests that the increase in BVD-positive calves is stemming from a significant increase in herd outbreaks. The number of herds identifying BVD-positive calves has increased by just 14 herds to reach 77 herds despite incidence of BVD doubling.

Meanwhile, the number of empty tags identified at the point of testing is running 0.4% lower with 6,710 empty tags, equating to 0.7% of all calves tested.

AHI programme manager for BVD Maria Guelbenzu said the increase in cases was disappointing.

“While it is early in the year to assess the impact of this increase and whether it will sustain, Animal Health Ireland is currently performing analyses to assess the reasons behind the increase,” she said.

The Irish Farmers Journal understands that negotiations are still ongoing between the Department of Agriculture, Food and the Marine, the BVD Implementation Group and farm organisations regarding the 2025 tag subsidy to help farmers cover the cost of testing.