August 2026 – Weanling Pneumonia Prevention

Pneumonia is an illness that can severely impact performance and, in some cases, cause death in weanlings. Even calves with minor infections, with no clinical signs, can be knocked back performance wise. Pneumonia is usually caused by a combination of several factors such as exposure to bacteria or viruses along with stressful or poor management practices.

Focusing on three key areas can help reduce the pneumonia risk on-farm. It can be as easy as A, B, C.

Stress causes a drop in immunity in calves which leaves them wide open to diseases such as pneumonia.

Stressful events include transport, weaning, painful procedures (disbudding) and mixing of groups. Try to avoid multiple stress events happening at the same time – space them out where possible.

Gradual weaning reduces stress of the calves. Removing cows slowly, creep feeding and use of anti-suckers are options to consider. Avoid the sudden removal of cows. Gradual weaning prevents a dramatic drop in weight and can save your ears a lot of pain. Ensure calves are adequately feed before and after weaning – at least 1.5kg /day of concentrates to ease this transition. Hungry animals are stressed animals.

Boosting immunity of calves gives them the best chance at fighting infection.

Vaccinations can help prevent disease or reduce the severity of disease. Vaccines can cover viruses such as Bovine Respiratory Syncytial Virus (BRSV) or bacteria such as Mannheimia haemolytica. Each product covers different strains, provides different lengths of immunity and have different dosage requirements. With so many options on the market – it’s best to talk to your vet and devise a plan. Complete the vaccination course weeks before weaning or other stress events.

Don’t let parasite control go by the wayside. Ensure you’re watching for signs such as coughing or scouring. Take consistent dung samples for egg counts (these are not always helpful for detecting lungworm). Unfortunately worm situations can change quickly due to the weather so keep a close eye, particularly when the rain returns.

Reduce the spread by reducing exposure risk where possible. This involves identifying sick animals, separating them from the healthy animals and getting them treated early. Once the disease is advanced, treatment doesn’t always lead to a full recovery.

Signs to look for:

• Dull, lethargic animals,
• Coughing,
• Panting
• Off feed
• Eye or nose discharge
• Temperature over 39.5◦C

Reduce diseases spreading onto your farm by keeping any new animals separate when they arrive. Keep them in a separate field or shed, away from your main herd for at least a week to ensure they are healthy. This gives you time to treat or vaccinate them as needed.

Housing can be another time when pneumonia becomes a problem. This can often be due to poor ventilation in the sheds. Cobwebs in the rafters or the strong smell of ammonia when the shed is full can be signs that the ventilation is insufficient. Fresh air circulation needs to be adequate without introducing draughts at the level of the animals. Review the inlets and outlets in the shed and make changes ahead of the housing season if needed.