The future of calf respiratory disease management

Understanding the pathogens

As an industry, we now understand more than ever about the pathogens involved in respiratory disease. Good vaccines exist for most, and it is possible to eradicate two viral causes – Bovine Viral Diarrhoea (BVD) and Infectious Bovine Rhinotracheitis (IBR) – from farming systems entirely. With reliable Polymerase Chain Reaction (PCR) diagnostics now widely available, we can safely assume that most farms harbour most pathogens within their animal populations. The critical question is why some calves develop disease while others do not. Vaccines play an important role in managing risk, but we must also focus on maximising the resilience and disease resistance of our cattle.

The long-term impact

The long-term effects of pneumonia are now better quantified. In beef systems, the impact on liveweight gain is clear. In dairy, respiratory disease in calves casts a long shadow over first lactation performance and herd survival beyond it. Daily liveweight gain data, increasingly collected on dairy farms, is helping raise industry standards. Rather than aiming to double birthweight by weaning, should we now aim to triple it? Subtle drops in pre-weaning growth rates below 0.8kg per day can have lasting effects on heifer and adult cow performance, setting the course for long-term-term productivity in those first eight weeks of life.

Improving detection

Detection remains a challenge. Stock people are skilled at identifying severe cases, but spotting early signs in larger groups is difficult. Cattle are evolutionarily hardwired to mask subtle symptoms, and coughing in dusty environments can become normalised. However, technology is advancing rapidly. Remote sensors, cameras and thermal imaging can detect reduced activity, lower feed intake, weight changes and temperature rises, potentially identifying clinical signs at the earliest possible stage. Combined with automatic drafting of at-risk animals, these tools offer real hope for reducing stress on both animals and farmers.

Trans-thoracic ultrasound has been another breakthrough, allowing vets to visualise lung damage directly. This technology often reveals higher levels of clinical and sub-clinical pneumonia than previously suspected. While processing this information can be sensitive, establishing a baseline creates the incentive for meaningful management changes.

Managing risk factors

Risk factors vary by farm, making active health planning with veterinary input essential. One universal consideration, however, is the impact of stress on immune response. Handling, transportation, and mixing of groups (particularly common in dairy-beef systems) trigger cortisol release, which compromises disease resistance. Systems that simplify loading, shorten journey times, maintain stable groups and reduce handling stress will have significant benefits.

For dairy systems, the highest risk period runs from birth through weaning and beyond. Colostrum and transition milk feeding remain fundamental to building calf resilience. Looking ahead, should each calf come with a colostrum passport, or should source farms be colostrum management accredited? There is another question worth asking – is our respiratory disease problem actually a calf scour problem at source? A calf that scours is far more likely to develop respiratory disease subsequently.

For beef suckler and finishing systems, air quality, ventilation capacity and stocking rates are the priorities for review. Shed capacity matters not only for the cold, damp days of autumn but also for managing heat-stress risk in the summer months.

Looking ahead

The industry now has a better understanding, better diagnostic tools and better technology for early detection than ever before. The challenge ahead lies in joining up supply chains so that each stage positively influences the next, with all eyes on more sustainable production and reduced reliance on treatment.

Interested in finding out more about this topic? Read Colin’s long read piece above