Bovine Respiratory Disease (BRD) is a challenging and economically important disease: a calf treated for BRD at 3 months of age or less is 2.5 times more likely to die after 3 months old, and have stunted growth in the first 6 months that will set her back for the rest of her life. Therefore, it’s incredibly important to prevent BRD by identifying it as early as possible!
Fortunately for us, Dr. Terri Ollivett and the UW School of Veterinary Medicine have developed a technique to monitor and identify BRD in calves by repurposing the ultrasounds veterinarians already use for pregnancy checks to visualize and score calf lungs via Thoracic Ultrasound (TUS).
TUS is useful for both individual calf decisions and herd level monitoring. For a particular calf, TUS will identify lung issues associated with a poor outcome such as chronic pneumonia, lung abscesses and lung necrosis, which can aid in culling decisions. At a herd level, TUS can identify the age group at risk, monitor prevalence and severity, the impact of ventilation changes and the effectiveness and accurate administration of vaccine and treatment protocols.
Monitoring BRD starts with a baseline: either a subset of a large group or all of a small group are scanned and scored. This data will identify the prevalence of BRD, age of onset, BRD subtype and duration of disease. How well workers are identifying calves with BRD can also be monitored with a TUS at the time of first treatment. Significant lung lesions at the time of treatment indicate late disease detection and that protocols and training on finding BRD in calves should be reviewed.
Combined with the Wisconsin Respiratory Score system, TUS identifies three subtypes of BRD: upper respiratory infections, clinical pneumonia or subclinical pneumonia. Severe subclinical pneumonia often goes undetected without TUS and is associated with a delay in disease detection, insufficient treatment, inconsistent nutrition or environmental challenges such as poor ventilation, drafts, or cold stress. Knowing the subtype of BRD will provide direction to finding the source of the problem.
Let us help reduce BRD in your calves! Dr. Bargren worked with Dr. Ollivett and learned about TUS directly from the source and other RVVC vets are trained. TUS is very fast: it only takes 20-30 seconds to scan each calf but provides a wealth of information that can influence the rest of a calf’s life, so it’s worth the time!