Pneumonia: The enemy of weanlings

Over the autumn months, a number of weanling-focused tasks are due to take place, such as: weaning; de-horning; castration if necessary; housing; and vaccination/dosing.

A plan should be put in place to ensure these jobs are carried out in a timely manner over the coming weeks, rather than all carried out on the same day, as this would put huge stress on weanlings.

Weaning is naturally stressful for two reasons: disruption of the cow-calf bond and dietary change from milk to forage.

A stressed calf will have lowered resistance to infections; poor immunity and disease (especially pneumonia) go hand-in-hand.

Pneumonia in cattle is a complicated, multi-factorial disease which means that many things can impact on its onset or course.

It is the most common cause of death in cattle of all ages over one month old. The word pneumonia basically means inflammation of the lungs.

What causes pneumonia in cattle?

Some of the agents that cause pneumonia live in the animal’s upper respiratory tract without causing disease.

However – under stressful conditions – the balance changes and these agents can start to multiply and move to locations, such as the lung, where they cause pneumonia.

The-high risk periods in cattle are those times when the animals are under increased stress. Examples include: change in weather; change in diet; and mixing of different groups.

How can I recognise it?

The cattle will likely be off their feed, empty looking and off form. There may be panting, coughing and/or have a watery or mucus discharge from the nose; often they may have an elevated temperature (>39.5ºC).

What can I do to treat pneumonia?

Antibiotics treat bacterial infections; they do not treat viral pneumonia. Most cases can get worse very quickly, so the best course of action is to talk to your vet who will advise you on the best treatment.

Antimicrobial resistance is an increasing problem in animal and human health; there is an onus on each and every one of us to use antibiotics responsibly.

In simple terms, this means using the right antibiotic at the right time and not overusing them as a crutch for poor management and housing.

For those animals that are treated and survive, it can still result in long-term lung damage, which affects life-long thrive. The graph below shows that cattle take significantly longer to fatten as a result of pneumonia.

How can I prevent pneumonia in cattle?

To prevent pneumonia in cattle, you need to minimise infectious pressure and maximise the animal’s immunity.

This means decreasing the amount of infection the animals are exposed to and increasing their immunity to the bugs that cause pneumonia.

  • Try to avoid exposing cattle to stressful conditions. Be mindful of any abrupt changes as animals tend to find these stressful. For example, when you are weaning, do it gradually and don’t suddenly change the diet;
  • When cattle are indoors, ensure sheds have a steady airflow and are well ventilated. A smoke-bomb-test can indicate the airflow and ventilation quality of the shed;
  • Avoid overstocking or mixing stock of different age groups;
  • If you notice an animal panting or off-form, try to remove it from the pen as it will act as a source of infection for other animals;
  • When you buy in animals, try to isolate them for a few weeks until you are happy they are not incubating infection.

Lungworm control

It is important that weanlings are dosed correctly and pasture management is taken into account.

Different dosing products have varying lengths of activity against worms; always read the instruction leaflet for the correct advice on the amount to administer, method of delivery and persistence of activity (if any).


When it comes to pneumonia, prevention is definitely better than treatment. As pneumonia can result from bacterial or viral infection, it is important to choose a vaccine that provides protection against both.

Bovilis Bovipast® RSP provides protection against viral (RSV and PI3) and Pasteurella (Mannheimia haemolytica serotypes A1 and A6 pneumonia). For the best results, calves need to be fully vaccinated two weeks before weaning.

With regards to Bovilis Bovipast® RSP, this means giving the first vaccine at six weeks pre-weaning and a booster four weeks later at two weeks pre-weaning.

A single dose of Bovilis IBR marker live may also be given at least two weeks pre-weaning. Bovilis IBR Marker Live can be given alongside Bovilis Bovipast RSP.

Bovilis Bovipast RSP is the only cattle pneumonia vaccine which contains IRP technology; what does this mean?

  • When bacteria like Mannheimia (Pasteurella) haemolytica reach the lungs of an animal, it needs iron to multiply and grow;
  • IRPs or iron regulated proteins on the surface of bacteria allow absorption of iron;
  • Animals vaccinated with Bovilis Bovipast RSP produce antibodies to these IRPs. These antibodies bind to the IRPs and reduce the bacteria’s ability to absorb iron and multiply;
  • When bacteria cannot absorb iron they have a reduced ability to cause disease.