Open Menu


IBR is caused by the bovine herpes virus. This virus causes three different types of disease: respiratory disease (IBR), venereal disease, and brain disease in calves. The main disease we see within the practice is the respiratory form.

Clinical Signs

  • Nasal discharge
  • Conjunctivitis (red eyes)
  • High temperature and milk drop
  • Loss of appetite
  • Pneumonia signs
  • Death in extreme cases


On the clinical signs described above. The signs of IBR are very variable. In some outbreaks, little more than a runny nose and red eyes is seen (although drops in milk yield can be large despite the apparently mild disease).

  • Nasal samples for virus testing from the respiratory tract
  • Blood testing for antibodies can identify infected cattle, particularly if paired samples are taken (3 weeks apart)
  • Post mortem examinations
  • Bulk milk tests


  • Biosecurity – Bought in cattle are the main source of the virus
  • Vaccination – There are several effective vaccines on the market. The main problem with most vaccines is that they produce antibodies which cannot be distinguished from those caused by natural infection. Thus, vaccinated cattle cannot be separated from latently infected cattle. A new marker vaccine is now available which does not produce the same antibodies as natural infection. This is helpful if you are trying to eliminate rather than control IBR
  • Environment – Adequate ventilation is needed to create a healthy environment for your herd

Remember vaccination in the face of an outbreak has been proven to reduce the severity of spread through your herd.

Please contact the clinic to speak to one of our vets if you require more information.