Cold Weather & Pneumonia in Calves – Vet Guide 2025 ❄️🐄

Hi there! I’m Dr Duncan Houston BVSc. Cold weather always brings a spike in calf pneumonia cases—and there's a good reason. Environmental chill impacts calf resistance, airway function, and immune response. In this 2025 vet guide, we’ll unpack the science behind the risk, prevention strategies, early detection, and how Ask A Vet can help you manage health during winter months.

1. Why Cold Weather Drives Pneumonia Risk 🧬

• Bacterial bloom: Chilly temperatures encourage growth of respiratory bacteria in nasal passages and airways, increasing pathogen load and risk of lung invasion.
• Thicker mucus: Cold thickens mucus, and stiffened mucus impedes airway clearance, making it harder for lungs to purge pathogens.
• Ciliary dysfunction: The microscopic cilia lining airways sweep out debris; thickened mucus hampers this ability, allowing pathogens deeper access to lower lungs.

2. Long-Term Impacts of Calf Respiratory Disease

• Dairy heifers that develop pneumonia as calves tend to calve for the first time later than healthy peers.
• Cows requiring multiple pneumonia treatments as calves produce ~10% less milk in their first lactation and ~15% less in the second.
• Respiratory illness causes economic losses—but also disrupts future herd productivity and longevity.

3. Prevention Strategies for Cold Seasons 🛡️

1. Warm, draft-free housing: Provide plenty of dry bedding, windbreaks, calf jackets when needed, and open ridge or side-vent ventilation without direct drafts.
2. Stable microclimates: Heat mats or targeted heat lamps can support thermoregulation during extreme cold.
3. Manage population density: Reduce overcrowding to limit pathogen exposure and stress.
4. Nutrition & immunity: Ensure sufficient energy and protein intake. Offer vitamins A, D, and E to support calf immune health.
5. Colostrum protocols: Ensure high-quality colostrum intake to build early systemic and mucosal immunity.
6. Early vaccination: Administer appropriate respiratory vaccines to calves before cold season begins.

4. Early Signs & Monitoring 🔍

Under cold stress, calves may slowly develop pneumonia:

• Frequent coughing, nasal discharge
• Increased respiratory rate or open-mouth breathing
• Reduced appetite or lethargy
• Fever, but it’s not always present

Observe calves daily—especially at dawn or right after feeding—and identify any subtle respiratory issues early.

5. Veterinary Diagnosis & Treatment Approach 💉

• Bacterial culture: If antibiotics fail, send nasal or lung samples; work with your veterinarian to identify correct treatments—Mycoplasma infections require specific antibiotics.
• Supportive therapy: Provide fluids, anti-inflammatories, and ensure ample nutrition.

6. Recovery & Long-Term Management

• Keep recovered calves in ventilated, clean environments to support convalescence.
• Maintain a robust vaccination and health-check schedule.
• Provide ongoing nutrition to support catch-up growth and future performance.
• Keep track of calves with respiratory issues to refine future prevention steps.

7. The Ask A Vet Edge 📱

Ask A Vet supports you with:

• Remote diagnosis help during cold weather pneumonia outbreaks
• Assistance with ventilation management and environmental design
• Support diagnosing antibiotic-resistant pathogens
• Tips for bedding, stress reduction, and convalescent care during winter
• Scheduling monitoring checklists and record‑keeping tools in the app

8. 2025 Take-Home Messages

• Cold weather thickens mucus and slows airway clearance, allowing pneumonia to take hold.
• Lung illness in calves affects performance, fertility, and milk yield later in life.
• Prevention through housing, ventilation, colostrum, nutrition, and vaccination is key.
• Early detection improves treatment outcomes—don’t wait!
• Ask A Vet provides essential support during the cold season.

Conclusion

Pneumonia in cold-weather calves isn’t just seasonal—it’s influential. With thoughtful housing, ventilation, nutrition, and wellness strategies, you can drastically reduce respiratory disease in calves and protect future herd productivity. Partner with Ask A Vet for tailored winter management and keep your calves—and your bottom line—thriving in 2025 and beyond. 🐮❤️