Infectious bovine rhinotracheitis (IBR) is a highly infectious viral disease in cattle caused by bovine herpesvirus 1 (BoHV-1).

According to Animal Health Ireland (AHI), evidence suggests that 75% of Irish cattle herds have been exposed to the virus.

The virus it typically spread by close contact with an infected animal, although airborne spread is also possible at a distance of up to 5m.

IBR can also be spread by contaminated semen, equipment and people.


Symptoms of possible IBR outbreak include:

  • Dullness and reduced appetite;
  • High temperature; rapid and loud breathing – sometimes with coughing;
  • Fluid discharge from nose and eyes;
  • Inflammation of the throat;
  • On occasion, death.

An outbreak of the disease will also have an impact on herd production, with reduced milk yields and abortion possible.

It is also possible to have a sub-clinical infection within the herd, with the first signs of an issue being reduced yields and poor reproductive outcomes.


Controlling the disease within a herd is a long-term process. This is because infected animals become latent carriers for life, developing antibodies that are detectable in blood and milk samples.

Detecting animals that are antibody-positive can be a reliable indicator of an IBR infection within a herd.

A reduction of spreading the virus within a herd can be achieved by selective culling and a vaccination programme.

Vaccinations play a key role in controlling the spread of IBR within your herd. It is important to note however, that vaccinating an already-infected animal will not remove the infection.

Already-infected animals should be identified and culled from the herd.

Vaccinations should be completed in line with manufacturer’s instructions. This reduces the likelihood that a non-infected animal will become infected.

It is also important that strict biosecurity measures are used; any purchased-in animals should be isolated until proven to be negative for the virus.


Continuous screening alongside a vaccination programme is key to controlling IBR within herds.

If you notice symptoms within your cows, further investigation is advised, to determine if IBR is the cause.

Farmers should use all the tools that are available to them to monitor their herds, with bulk tank screening a useful way of monitoring IBR within herds.