Ahead of the 2026 spring-calving breeding season, Animal Health Ireland (AHI) is urging farmers to ramp up biosecurity measures to help stamp out bovine viral diarrhoea (BVD).

Detailed analysis by AHI shows that herds located within 400m of a confirmed BVD case in 2025 or 2026, face a significantly increased risk of infection.

The data indicates that these herds have a one-in-seven chance of becoming positive the following year, even if they have no prior history of infection.

Reviewing on-farm biosecurity in consultation with a veterinary practitioner is critical at this time of year, according to AHI.

All pregnant animals can become infected with BVD, but heifers are particularly vulnerable as they tend to have lower immunity.

Exposure during early pregnancy can result in the birth of infected calves.

Key BVD biosecurity measures before breeding

AHI highlights several crucial steps farmers can take to protect their herds:

Boundary management: Avoid grazing cows and heifers in early pregnancy near boundaries where nose-to-nose contact with neighbouring cattle occurs;
Vaccination: While not preventing virus entry, vaccination reduces the impact of accidental exposure and should be considered as part of a herd health plan;
Quarantine practices: Isolate all purchased or returning cattle for a minimum of 28 days. Calves from introduced pregnant animals should be tested promptly and kept separate until confirmed negative;
Hygiene protocols: Ensure all farm visitors and workers follow strict cleaning and disinfection procedures;
Equipment control: Minimise sharing of equipment such as trailers and calving jacks between farms. If completely unavoidable, thoroughly clean and disinfect before use.

Commenting on the need to take steps in 2025 to protect herds in 2026, Dr. Maria Guelbenzu, BVD programme manager at AHI said: “The decisions of today impact us all tomorrow. That is why we are urging farm families and their vets to ramp up efforts to protect herds from BVD.

"Acting now will protect your herd’s health, improve productivity and profitability while supporting the national goal of BVD eradication.

"Farmers, their vets and their entire industry have made huge strides in eradicating BVD and we are now closer than ever to achieving BVD freedom," she said.