Bovine Respiratory Disease—better known as BRD—isn’t just one illness. It’s a catch-all term for respiratory diseases in cattle, most often showing up as pneumonia or shipping fever. While it’s common in stocker and feedlot operations, cow/calf producers aren’t immune to it either.
Why is BRD such a problem in feedlots? The answer is stress—a lot of stress. Calves fresh from weaning are suddenly hauled, mixed with unfamiliar cattle, and placed in new environments. This combination of stressors weakens their immune systems and makes them more vulnerable to respiratory infections.
A mix of factors working together causes BRD:
- Environmental stressors: weaning, transport, commingling, crowding, and sudden diet changes.
- Host factors: calf age, immune status, and overall health.
- Pathogens: bacteria, viruses, and sometimes both.
Even on pasture, BRD can be a serious concern. Nearly 20% of cow/calf operations deal with nursing-calf pneumonia, which is the leading cause of death for calves three weeks and older. That’s why prevention matters—whether you’re managing hundreds of head in a feedlot or just a few pairs in the pasture.
