Calf pneumonia or Bovine Respiratory Disease (BRD) is a complex, multi-factorial disease usually seen in young, housed calves. BRD causes inflammation and damage to the lungs and airways which is often irreversible.

There are many viruses and bacteria which can cause pneumonia in calves, even neighbouring farms may have different viral and bacterial challenges. The only way to know what is causing disease in your herd is to test – this involves taking bloods, nasal swabs or samples of lung tissue if you have any losses. Testing is particularly useful if you have a disease outbreak and want to target treatment or to influence future vaccination programmes. However, other factors also play a role in disease outbreaks including weather, ventilation, stressors (e.g. mixing, weaning or overstocking) and the immune status of the calves (BVD).

Clinical Signs of advanced pneumonia can be easy to spot. These include:

  • Reduction in feeding
  • Dull demeanour
  • Dropping of the head
  • Increased respiratory rate
  • Nasal discharge
  • Cough

One of the first signs that a calf is suffering from pneumonia is an increased temperature, but this can occur days before the onset of other signs. Taking an animal’s temperature can allow detection and treatment of disease before it becomes more severe and permanent damage occurs.

Ensuring your calves have a strong immune status can reduce cases of pneumonia. The quality and quantity of colostrum a calf consumes affects its ability to fight off disease, so making sure that calves receive 3-4 litres, or at least 10% of their bodyweight of colostrum within 2-4 hours of birth is essential.

Vaccination protocols can also strengthen immune status, resulting in reduced losses associated with pneumonia and improved growth rates. The following points are useful to consider when thinking about vaccine use:

  • Route of vaccination – each produces immunity via different mechanisms – they are not just alternative forms of administration!
  • Intranasal vaccines give a quicker onset of cover, but for a shorter time period.
  • Most injectable vaccines must be given as two doses. The first primes the immune system and the second gives duration of cover by reinforcing the immune response. Protection is not complete until 2 weeks after the second dose.