In the last few months, we have started carrying out routine calf lung scanning for some of our dairy clients. This has been a really valuable learning exercise to gain more in-depth insights into respiratory disease in heifer calves. Before long we won’t be far away from peak respiratory disease season. As always, getting ahead of the game is the aim for preventative health care, so here I discuss a bit more about calf lung scanning, how it can be implemented on farm, and the benefits of using it as part of a routine calf health monitoring programme.
What is it and why is it useful?
Lung scanning is the process of using our ultrasound scanners, that we normally use for PDing cows, to scan calves’ chests. This allows us to visualise the lung tissue and assess if there is any consolidation (areas of infected lung that aren’t functional) indicating respiratory disease. Interestingly, this consolidation often comes much earlier, up to a week, than the development of clinical signs (such as coughing, nasal discharge, and fever). This means we are often detecting and treating cases of respiratory disease much earlier than by using traditional detection methods such as scoring charts on farm or clinical examination. In many cases, this leads to shorter courses of antibiotics, and better resolution of consolidated tissue. If left untreated this can have long term detrimental impacts on calf growth rates, and even into lactation with decreased yields and increased risk of early culling.
Implementation on Farm
So far, we have applied this technique in different ways depending on requirements specific to each farm. As a “one-off” for a cohort of calves, we can scan around the time of weaning, to assess for areas of consolidated lung that will lead to poorer performance as an adult cow. We have then been using this extra information, alongside health history and growth rates, to make appropriate selections for which animals to breed from and eventually enter the adult herd. This also gives us an idea of how successful our pneumonia control has been in the pre-weaning period, and subsequently investigate any problems that we may find. Another approach we have taken is weekly visits, where we scan calves a week prior to the time we would usually see clinical signs on farm, to identify calves in the early stages of pneumonia, before signs develop. This allows for prompt treatment and earlier resolution of the disease to minimise long term impacts and reduce antibiotic use.
This is not a one-size-fits-all approach, and certainly not a silver bullet to solve all pneumonia issues, but it can provide some useful information and be incorporated into a wider management plan for controlling pneumonia in your calves. If you are interested and want to hear more, as always, we’d recommend having a chat with your routine vet to see if it’s something that may be of benefit to your calves
Written By Tom Angel, BVetMed PGDipVCP MRCVS Veterinary Surgeon
