Longer days, lush green pastures, and the hum of summer are the hallmarks of the season on a farm. Yet as temperatures rise, so do the risks to your herd’s health. Summer illnesses can spread fast through livestock, turning what should be a time of abundant grazing and growth into a season of costly setbacks and stress.
From pinkeye to foot rot, hot weather and high humidity create perfect conditions for pathogens, parasites, and insects to thrive. Understanding why summer increases disease risks—and what proactive steps you can take—can mean the difference between a healthy, productive herd and lost animals or profits.
Farmers throughout the Tri-State area know how quickly a single case of disease can turn into a herd-wide problem. Being prepared is your best defense.
Why Summer Challenges Livestock Health
Warm weather doesn’t just make animals uncomfortable. Heat stress directly weakens the immune system, lowering resistance to infections. High humidity adds another layer of danger by making it difficult for animals to cool off, further stressing their bodies.
Rainfall during summer can leave pastures muddy and wet, perfect conditions for bacteria and parasites to multiply. Meanwhile, insects like flies and mosquitoes thrive, carrying disease from one animal to the next. Flies alone can cause a range of issues, from transmitting pinkeye bacteria to creating open sores through constant biting.
All of these factors combine into a challenging environment for livestock health. Without proper preventive care, even minor problems can quickly escalate.
Common Summer Diseases to Watch For
Keeping your animals safe starts with knowing which diseases are most common during the summer months in the Tri-State area:
- Pinkeye (Infectious Bovine Keratoconjunctivitis)
Dust, tall grass, bright sunlight, and flies irritate eyes, creating an entry point for bacteria. Pinkeye spreads fast in herds and can cause corneal ulcers, blindness, and decreased weight gain if not treated quickly.
- Summer Mastitis
Non-lactating cows and heifers are especially vulnerable when grazing in wet, insect-infested areas. Bacteria enter the teat canal, causing painful udder swelling, fever, and foul-smelling secretions.
- Foot Rot
Wet, muddy pastures soften the skin between hooves, allowing bacteria to invade and cause sudden, severe lameness. Animals with foot rot lose weight rapidly because pain makes them reluctant to eat or move.
- Clostridial Diseases (Blackleg and others)
Clostridia bacteria live in soil and can infect young, fast-growing calves through bruises or wounds. Blackleg often causes sudden death without warning.
- Fescue Toxicosis
Cattle and sheep grazing on endophyte-infected fescue can suffer heat intolerance, poor weight gain, decreased milk production, and reproductive issues during hot months.
Each of these diseases can spread quickly and cause severe health problems if not addressed early. Recognizing the signs and acting promptly are key to keeping your animals safe.
Proactive Steps to Prevent Summer Diseases
Effective prevention plans are built on simple but powerful strategies that protect your herd from the heat, stress, and increased disease risks of summer.
- Provide Constant Access to Clean, Cool Water: Water is important for animals to regulate their body temperature. Dehydration makes heat stress worse and can quickly lead to serious illness.
- Improve Shade and Ventilation: Trees, run-in sheds, and barns with good airflow give livestock places to cool down. Mechanical fans in barns or milking parlors can make a dramatic difference on sweltering days.
- Reduce Fly and Parasite Populations: Implementing fly control measures like ear tags, pour-on insecticides, feed-through larvicides, or insecticide sprays minimizes irritation and disease spread. Managing manure and standing water reduces breeding grounds for flies and mosquitoes.
- Rotate Pastures: Moving livestock to fresh paddocks prevents overgrazing and breaks parasite life cycles. Resting pastures also helps control worm burdens.
- Stay Up to Date on Vaccinations and Deworming: Work with your veterinarian to customize vaccination and parasite control schedules to your farm’s unique needs. Timely clostridial vaccinations protect against deadly diseases like blackleg, while deworming reduces parasite loads that weaken animals.
- Keep Pastures Healthy: Monitor and manage tall fescue pastures, especially in hot months. Consider planting endophyte-free or novel endophyte fescue varieties to reduce the risk of toxicosis.
- Watch for Early Warning Signs: Inspect animals daily for signs of illness, injury, or heat stress. Early detection allows quick intervention, saving lives and preventing herd-wide outbreaks.
When to Call for Veterinary Help
Sometimes, even with excellent management, animals can become ill. Prompt veterinary care can mean the difference between a quick recovery and severe complications. Farmers should reach out to their veterinarian if they notice:
- Red, cloudy, or runny eyes; squinting or blinking frequently
- Swollen udders with unusual or foul-smelling secretions
- Sudden lameness or reluctance to bear weight
- High fever, lethargy, or reduced appetite
- Sudden deaths among young animals
Acting quickly protects not only the sick animal but also prevents the spread of contagious diseases throughout the herd.
Support from Tri-State Veterinary Services
Tri-State Veterinary Services is proud to partner with farmers across Connecticut, Massachusetts, and New York to keep livestock healthy year-round. Our experienced veterinarians know the unique challenges local farmers face during the summer, and we’re dedicated to helping you prevent and manage seasonal diseases.
Whether you need on-farm consultations, herd health planning, or emergency services, the team is ready to help you protect your investment. Our veterinarians develop customized vaccination schedules, parasite control programs, and pasture management recommendations tailored to your operation’s size and goals.
In addition to hands-on veterinary care, Tri-State Veterinary Services offers convenient access to trusted products through the online pharmacy. Ordering vaccines, dewormers, fly control products, and other supplies online saves time, letting you focus on what you do best—caring for your animals.
Safeguard Your Herd This Summer
Summer should be a time of growth and productivity, not worry over preventable diseases. By taking proactive steps like providing clean water, ensuring shade, controlling flies, and vaccinating on schedule, you can dramatically reduce the risk of illness in your herd.
If you have questions about building a prevention plan or notice signs of disease in your livestock, don’t wait. Contact Tri-State Veterinary Services today at (860) 459-0986. Together, we can make sure your animals stay healthy and productive all season long.