Treating pneumonia in cattle starts with early detection and prompt antibiotic therapy, combined with anti-inflammatory support and proper hydration. Pneumonia, the most common and costly disease in beef and dairy operations, is rarely caused by a single pathogen. It’s typically a chain reaction: stress and viral infections weaken the respiratory tract, allowing bacteria already living in the animal’s airways to invade the lungs. The faster you identify and treat a sick animal, the better the outcome.
Recognizing Pneumonia Early
The classic signs are rapid breathing or panting, coughing, nasal discharge, droopy ears, and loss of appetite. A rectal temperature above 102.5°F signals fever, and cattle with pneumonia often spike above 104°F. These symptoms frequently appear a few days after a stressful event like weaning, transport, or commingling with new animals.
Visual observation catches many cases, but it misses subtle ones. Manual lung auscultation with a standard stethoscope has been shown to be unreliable among practitioners. A newer option is computer-aided lung auscultation, such as the Whisper Veterinary Stethoscope, which records thoracic sounds and uses a machine-learning algorithm to generate a severity score from 1 (healthy) to 5 (severely compromised). In a study of over 2,700 feeder cattle, higher scores at first diagnosis were significantly associated with both retreatment risk and mortality. The system correlates strongly with the extent of lung lesions found at slaughter, giving you a much clearer picture of how damaged the lungs already are.
Thoracic ultrasound is another tool gaining traction, especially in calf operations. It classifies lung consolidation by depth: less than 1 cm is mild, 1 to 3 cm is moderate, and 3 cm or more is severe. These categories matter for prognosis. Calves with mild consolidation at treatment had a short-term cure rate of about 59%, while calves with severe consolidation cured at only 33%. Even at 10 to 12 weeks out, calves with persistent severe lung damage gained roughly 100 grams per day less than healthier calves and produced over 7 kg less carcass weight.
What Causes It
Four bacteria drive the majority of bovine respiratory disease. The most frequently isolated is one that causes severe, hemorrhagic lung inflammation and is the dominant pathogen in recently weaned feedlot cattle and in calves with enzootic pneumonia. A second common bacterium tends to colonize lungs that are already damaged, causing purulent (pus-filled) infection. A third can trigger not only pneumonia but also heart inflammation and widespread infection in multiple organs. The fourth is associated with chronic pneumonia and joint infections in feedlot cattle, and calves infected with it often develop ear infections and swollen joints alongside their lung disease.
These bacteria don’t usually cause problems on their own. Viral infections, such as bovine respiratory syncytial virus, infectious bovine rhinotracheitis, or parainfluenza-3, typically come first and damage the airway lining. Stress from weaning, shipping, weather changes, or overcrowding suppresses the immune system and opens the door for bacterial invasion. One particularly aggressive bacterium can cause sporadic outbreaks with sudden death or high mortality even with aggressive treatment.
Antibiotic Treatment
Antibiotics are the cornerstone of pneumonia treatment in cattle. Your veterinarian will select an antibiotic based on the suspected pathogen, the animal’s history, and what has worked on your operation before. Long-acting injectable antibiotics are the standard because they maintain effective drug levels for days with a single injection, reducing handling stress on a sick animal. Common choices include macrolides, phenicols, and advanced-generation antibiotics, each with different spectrums of activity and meat withdrawal periods you need to follow.
Timing matters more than which specific drug you choose. Cattle treated at the first signs of illness respond far better than those treated after the disease has progressed. Once significant lung consolidation has set in, antibiotics can clear the infection but cannot reverse the scar tissue. That’s why the early detection tools described above are so valuable: they help you decide not just whether to treat, but how aggressively.
If an animal doesn’t respond to the first antibiotic within 48 to 72 hours, a second-line treatment with a different drug class is typically used. Chronic non-responders, especially those with joint swelling or ear infections, may have a pathogen that is inherently resistant to many antibiotics and carries a poorer prognosis.
Anti-Inflammatory Support
Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly given alongside antibiotics to reduce fever, ease pain, and help cattle feel well enough to return to the feed bunk. Meloxicam is frequently paired with antibiotics in combination products. These drugs bring down rectal temperature and improve comfort, which can encourage eating and drinking during recovery.
There’s an important nuance here, though. Research on giving NSAIDs alone, without antibiotics, early in a viral respiratory infection has not been encouraging. In one study, calves given meloxicam or aspirin early during a viral respiratory infection showed no reduction in clinical signs or lung damage. In another case, a different NSAID actually worsened lung inflammation in calves being treated for a bacterial infection. The takeaway: NSAIDs work best as part of a combined treatment plan with antibiotics, not as a standalone early intervention.
Hydration as Adjunct Therapy
Dehydration is an underappreciated problem in cattle with pneumonia. Sick animals eat and drink less, and fever increases fluid loss. When a calf becomes dehydrated, the mucus lining the airways gets thicker and stickier, making it harder for the respiratory tract to clear bacteria and debris. The tiny hair-like structures (cilia) that sweep mucus out of the lungs need adequate hydration and energy to function properly.
A recent study found that calves receiving oral rehydration therapy alongside their antibiotic treatment gained more weight than calves treated with antibiotics alone. The protocol used water mixed with a glucose-electrolyte solution at roughly 7% of body weight per day, divided into multiple feedings of no more than 3 liters each, administered by suckle bottle or tube for five days after diagnosis. The glucose and electrolytes support the energy needs of airway cells and improve mucus quality, helping maintain the physical barrier in the upper respiratory tract.
Housing and Environment
Where cattle live plays a direct role in pneumonia risk and recovery. Poor ventilation traps ammonia, moisture, and airborne pathogens at animal level. For calves, individual housing, whether indoors with good airflow or outdoors in hutches, consistently reduces respiratory disease compared to group housing in enclosed barns.
Deep straw bedding outperforms other bedding materials as an insulator. Calves in the first two weeks of life need ambient temperatures above 10 to 15°C to avoid diverting energy toward staying warm, and drafts dramatically increase heat loss. A high “nesting score,” meaning enough straw that calves can nestle into it with their legs tucked under the bedding, has a measurable preventive effect against respiratory disease in naturally ventilated barns. For sick animals recovering from pneumonia, a dry, draft-free, deeply bedded area helps the animal conserve energy for immune function and healing rather than thermoregulation.
Preventing the Next Outbreak
Vaccination is the most effective long-term tool for reducing pneumonia incidence. Standard preconditioning programs vaccinate calves at weaning and revaccinate 30 days later at feedlot arrival. But the timing of those doses can make a significant difference. In a controlled study, calves vaccinated 15 days before weaning and revaccinated 15 days before feedlot entry had a BRD incidence of about 17%, compared to 32% in calves vaccinated at weaning or 15 days after. Giving both vaccine doses before the animal faces the combined stress of weaning and transport, rather than during or after, cuts the disease rate nearly in half.
Beyond vaccination, the management basics matter: minimize commingling of animals from different sources, reduce transport time and stress, ensure adequate nutrition before and after weaning, and keep new arrivals separated for observation. Pneumonia in cattle is never entirely preventable, but the combination of strategic vaccination timing, low-stress handling, good housing, and rapid treatment when disease does appear gives you the best chance of keeping losses low and recovery rates high.