BRD might be the most expensive disease you're not fully accounting for. Beyond treatment and death loss, it's quietly draining performance and profits from your closeouts. Let's explore how BRD impacts your operation and what you can do about it.
What BRD Really Does to Performance
When cattle get sick, their bodies divert energy and nutrients away from growth and toward fighting infection. Here's how:
- The "Energy Sink" – Immune system activation turns immune cells into glucose hogs, reducing energy available for growth.
- Fever reduces dry matter intake (DMI), slowing weight gain.
- Cortisol and cytokines cause insulin resistance, limiting glucose uptake by muscle tissue.
- The liver produces acute-phase proteins by breaking down muscle for amino acids.
- Antibody production consumes protein resources.
How Immunosuppression Originates
Stress and dehydration weaken the immune system, making cattle more vulnerable to respiratory infections:
- Cortisol elevations over 24 hours: Elevated cortisol suppresses interferon, antibody production, and antimicrobial peptides (AMPs).
- Dehydration: Dehydration thickens mucus, impairing clearance and creating a breeding ground for bacteria.
- Insulin resistance: Cortisol and cytokines cause insulin resistance in immune cells.
- Fight or flight response: Stress hormones like epinephrine can trigger virulence in bacteria via quorum sensing.
- Metabolic syndrome: Over-conditioned calves may suffer from metabolic syndrome, further weakening immunity.
As cattle are moving through normal channels, they are exposed to numerous upper respiratory tract (URT) viruses. Considering the immunosuppression, these viruses now flourish in the URT, causing enough damage to predispose the tract to bacterial infection. The common BRD bacteria, namely Mannheimia, Pasteurella, Histophilus, and Mycoplasma are commensals of the nasopharynx. With viral damage to the URT, these bacteria begin to proliferate and migrate down into the depths of the lungs and cause bronchopneumonia, which we now call the BRD Complex.
The Hidden Costs Behind the BRD Complex
At first glance, it seems as though drug treatment costs would be the largest cost incurred from BRD, when in fact, as we will show, the loss of performance and mortality costs make up a bigger chunk of our BRD losses. Kemin developed a BRD Calculator that helps quantify the true cost of BRD for every 1% increase in morbidity. It factors in:
- In-weight and purchase price
- Projected out-weight, ADG, and feed-to-gain ratio
- BRD morbidity and case fatality rate
- Mortality cost and railer price
- Quality grade and choice/select spread
- Dry matter ration cost
Morbidity note: 67% of first pulls will be treated once; 33% of first pulls will be treated 2 or more times.
Cattle treated for BRD incur various performance losses during their stay at the feedyard, depending on how many times an animal has been treated. These parameters were derived from ranch-to-rail data and other industry data.
Performance losses vary by treatment frequency: