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

Hello, I’m Dr Duncan Houston BVSc. Cold weather isn't just uncomfortable for your calves—it can be dangerous. Winter conditions significantly raise the risk of respiratory infections and pneumonia, especially in vulnerable calves. In this 2025 guide, we’ll explore the science behind cold-induced pneumonia, prevention strategies, treatment tips, and how Ask A Vet can support your herd through the coldest months. 🧬🌡️

1. Why Cold Weather Increases Pneumonia Risk 🧫

In frigid temperatures, respiratory bacteria flourish in the calf’s nose and throat. Cold air also thickens mucus, impeding the function of cilia—tiny hairs lining the airways that sweep pathogens out. 🦠❌

• More bacteria + impaired clearance = pneumonia risk.
• Chilled air slows cilia, allowing bacteria to settle deep into the lungs.
• Once lower lungs are colonized, inflammation and respiratory symptoms escalate quickly.

2. How Cold Affects Calf Lung Defenses ❄️💨

• Thicker mucus: Traps more pathogens, but doesn't clear easily.
• Reduced ciliary motion: Less movement = less clearance.
• Increased exposure: Damp, drafty housing raises microbial loads.

This chain reaction compromises lung defenses, making cold a high-risk season for pneumonia outbreaks. 🐄🧠

3. Long-Term Consequences of Pneumonia 💔

Cold-season pneumonia isn’t just an acute problem—it affects calf development:

• Dairy heifers with calfhood pneumonia calve later on average.
• Cows treated >1x for pneumonia produce:
• 🍼 10% less milk in their 1st lactation
• 🍼 15% less milk in their 2nd lactation
• More treatments = more antibiotic resistance & cost.

4. Prevention: Housing, Hygiene & Nutrition 🏠🧼🥣

✅ Housing & Airflow

• Ensure clean, dry, draft-free pens with fresh bedding
• Ventilate with an open ridge or side inlets—no direct drafts
• Use calf jackets for added warmth without limiting airflow

✅ Hygiene

• Disinfect bottles, feeders, and stalls regularly
• Keep bedding dry and deep—especially during snow or sleet

✅ Nutrition

• Feed high-energy milk replacers and clean starter
• Supplement with vitamins A, D, and E to support immune function

5. Watch for Early Signs 👀🚨

Early detection saves lives. Signs to monitor:

• 🐄 Coughing or nasal discharge
• 🐄 Increased respiratory rate or effort
• 🐄 Drooped ears, dull behavior, decreased appetite
• 🐄 Fever over 103°F (39.4°C)

6. What to Do If Calves Get Sick 💊

• Call your vet: Don’t wait to see if it “passes”
• Antibiotics: Bacterial strains vary—culture to select correct treatment
• Mycoplasma? This bacteria needs specific antibiotics—get a lab confirmation
• Supportive care: Electrolytes, warmth, and palatable feed

7. Ask A Vet Helps You Winter-Proof Your Herd 📱🐄

• 👩‍⚕️ On-call respiratory protocol assistance
• 📋 Custom calf monitoring checklists
• 🧪 Help interpreting culture and treatment results
• 📈 Prevention strategies specific to your barn and region

8. Winter Calf Survival Checklist ✅❄️

• Warm, dry, draft-free shelter 🏠
• Good bedding and calf jackets 🛏️🧥
• Clean feeders and bottles 🧼
• Fresh air without direct wind 🌬️
• Nutrition + vitamin support 🥛
• Quick response to signs of illness 🚑
• Ask A Vet backup for emergencies 📲

9. Take-Home Messages for 2025 🐄💡

• Cold thickens mucus, slows cilia, and increases bacterial load ❄️🦠
• Calves need dry warmth and ventilated barns to stay safe 🏠🔥
• Early pneumonia treatment avoids long-term productivity loss 🩺🍼
• Mycoplasma is difficult to treat—get lab confirmation 🧪📋
• Ask A Vet is here to help—any time, in any weather 🌨️📱

Conclusion

Winter pneumonia in calves is serious but preventable. With vigilant observation, clean housing, supportive feeding, and fast treatment, your herd can stay healthy—even in harsh cold. 🐄❄️ Don’t hesitate to reach out to Ask A Vet for help creating winter-proof protocols or responding to the first sign of sickness. Together, let’s protect your calves and your future productivity. ❤️📈