The Threat of BRSV: How Vaccination Helps

Bovine Respiratory Syncytial Virus (BRSV) poses a significant threat to cattle health, especially young calves, causing severe respiratory illness and economic losses. Vaccination is the most effective and widely recommended strategy to protect herds, reduce disease severity, and minimize outbreaks. By stimulating a strong immune response, vaccines help cattle resist infection, leading to healthier animals and more profitable operations.

Raising healthy calves is a top priority for any cattle producer. However, invisible threats like Bovine Respiratory Syncytial Virus (BRSV) can quickly turn a thriving calf crop into a costly challenge. This common and highly contagious respiratory disease can spread rapidly, leading to sick animals, expensive treatments, and even fatalities. The frustration of seeing your hard work undermined by preventable illness is understandable. But there’s good news: you’ve come to the right place to understand BRSV and, more importantly, discover the most effective and practical solution. Let’s explore how vaccination acts as a powerful shield against this pervasive threat, safeguarding your herd’s health and your farm’s future.

Understanding the Threat: What is Bovine Respiratory Syncytial Virus (BRSV)?

Bovine Respiratory Syncytial Virus (BRSV) is a major player in the bovine respiratory disease (BRD) complex, often called “shipping fever.” It’s a highly contagious virus that primarily targets the respiratory system of cattle, particularly young calves. While adult cattle can also be infected, they often show milder symptoms or no symptoms at all, acting as carriers that can spread the virus to more vulnerable animals.

The Impact of BRSV on Calf Health

When BRSV strikes, it damages the cells lining the airways and lungs. This damage makes the calves more susceptible to secondary bacterial infections, which often lead to more severe and prolonged illness. The symptoms can range from mild to life-threatening, depending on the calf’s age, immune status, and the presence of other stressors or co-infections.

Common Symptoms of BRSV Infection:

Fever: Often one of the first signs, calves may have a high body temperature.
Coughing: A persistent, often deep, moist cough is typical.
Nasal Discharge: Clear at first, but can become thick and yellowish as secondary infections develop.
Difficulty Breathing: Rapid, shallow breathing, open-mouth breathing, or extended neck to ease breathing.
Loss of Appetite: Sick calves will eat less or stop eating entirely, leading to weight loss and weakness.
Depression: Calves may appear lethargic, stand with a lowered head, and be unresponsive.
Eye Discharge: Watery eyes can also be observed.
Pneumonia: In severe cases, BRSV can lead to severe pneumonia, which can be fatal.

The severity of BRSV outbreaks can vary greatly. In some herds, it might cause a few sniffles and coughs, while in others, it can lead to widespread illness, high mortality rates, and significant economic losses. This variability makes it a particularly insidious threat, as its true impact isn’t always immediately apparent until it’s too late.

How BRSV Spreads and What Makes it Worse

BRSV is primarily spread through direct contact between infected and susceptible animals. Coughing and sneezing release virus particles into the air, which can then be inhaled by other cattle. It can also spread indirectly through contaminated equipment, feed, or water, though airborne transmission over short distances is the most common route.

Several factors can increase the risk and severity of BRSV outbreaks:

Stress: Weaning, transportation, commingling of calves from different sources, and changes in diet are major stressors that weaken a calf’s immune system, making them more vulnerable.
Poor Ventilation: Overcrowded barns with inadequate airflow trap virus particles, increasing the viral load and the likelihood of transmission.
Co-infections: BRSV often works in tandem with other viruses (like Bovine Viral Diarrhea Virus – BVDV, Infectious Bovine Rhinotracheitis – IBR, Parainfluenza-3 – PI3) and bacteria (like Mannheimia haemolytica and Pasteurella multocida). These co-infections complicate the disease and worsen its outcome.
Age: Young calves (typically between 1 and 6 months of age) are most susceptible due to their developing immune systems and waning maternal antibodies.

Understanding these factors is crucial for developing a comprehensive prevention strategy that goes beyond just vaccination.

The Economic and Welfare Impact of BRSV on Farms

The threat of BRSV extends far beyond individual sick calves; it can have a devastating impact on a farm’s bottom line and the overall welfare of the herd. Recognizing these costs helps underscore the importance of proactive prevention.

Direct Economic Losses

BRSV outbreaks lead to a cascade of financial drains:

Treatment Costs: Veterinary visits, antibiotics for secondary bacterial infections, anti-inflammatory drugs, and supportive care (e.g., electrolytes, fluids) add up quickly.
Reduced Performance: Sick calves eat less, gain weight slowly, or even lose weight. This leads to delayed market readiness, lighter weights at sale, and reduced feed efficiency.
Mortality: While not always the highest percentage, deaths due to BRSV and associated pneumonia are the most direct and irreversible economic loss.
Labor Costs: Caring for sick animals requires significant extra labor, diverting time and resources from other essential farm tasks.
Cull Rates: Chronically ill calves that fail to thrive may need to be culled, representing a loss of potential future production.

Indirect Economic Losses

The ripple effect of BRSV can be felt throughout the operation:

Reduced Reproductive Performance: Stress and illness in young stock can impact their long-term health and future reproductive capabilities, especially in heifers.
Impact on Reputation: Farms with a history of disease outbreaks may face challenges selling calves, potentially receiving lower prices due to buyer concerns.
Disruption to Farm Schedule: Managing a disease outbreak can disrupt breeding schedules, marketing plans, and overall farm management.

Animal Welfare Concerns

Beyond the financial implications, BRSV significantly compromises animal welfare. Sick calves experience pain, discomfort, difficulty breathing, and general malaise. Prolonged illness can lead to chronic respiratory issues, poor growth, and a diminished quality of life. From an ethical standpoint, preventing such suffering is a responsibility of every producer.

The cumulative effect of these losses highlights that preventing BRSV is not just a health issue, but a critical business decision for sustainable and profitable cattle farming.

The Science Behind BRSV Vaccination: How it Helps

Vaccination is the cornerstone of BRSV prevention. It works by safely introducing components of the virus to the calf’s immune system, training it to recognize and fight off the actual infection when encountered in the field. This proactive approach is far more effective and less costly than treating sick animals.

How Vaccines Work

Vaccines contain weakened or inactivated forms of the virus, or specific viral proteins. When administered, these components stimulate the calf’s immune system to produce antibodies and specialized immune cells. These antibodies and cells then “remember” the virus. If the calf is later exposed to the live BRSV, its immune system can quickly mount a strong defense, neutralizing the virus before it causes severe disease.

Types of BRSV Vaccines

There are generally two main types of BRSV vaccines available:

Modified-Live Virus (MLV) Vaccines:
- Contain a weakened form of the live virus that can replicate in the animal but does not cause disease.
- Typically stimulate a strong, long-lasting immune response, mimicking natural infection.
- Often provide faster protection.
- Can sometimes cause mild, transient side effects.
- May not be suitable for pregnant animals unless specifically labeled for use in pregnant cows or calves nursing pregnant cows.
Killed Virus (KV) Vaccines:
- Contain inactivated (killed) virus particles that cannot replicate.
- Generally considered safer for all animals, including pregnant cows.
- Often require more doses (priming and booster shots) to achieve sufficient immunity.
- Immunity may not be as robust or long-lasting as MLV vaccines.

The choice between MLV and KV vaccines depends on the specific farm situation, veterinary advice, and the manufacturer’s recommendations. Many vaccines are combination products, protecting against BRSV along with other BRD pathogens like IBR, BVDV, and PI3.

Benefits of BRSV Vaccination

Vaccinating against BRSV offers numerous advantages:

Reduced Disease Severity: Vaccinated calves, even if exposed to BRSV, typically develop much milder symptoms, if any, compared to unvaccinated calves. This means less suffering and faster recovery.
Lower Mortality Rates: By preventing severe pneumonia and secondary infections, vaccination dramatically reduces the number of deaths attributable to BRSV.
Decreased Treatment Costs: Fewer sick animals mean less need for veterinary interventions, antibiotics, and other medications, saving significant money.
Improved Performance: Healthier calves eat more, gain weight faster, and reach market weight sooner, improving overall farm profitability.
Enhanced Herd Immunity (Herd Effect): When a large percentage of the herd is vaccinated, it reduces the amount of virus circulating in the environment. This protects even unvaccinated or immunocompromised animals, creating a “herd immunity” shield.
Reduced Stress and Labor: A healthy herd is easier to manage, reducing the stress on both animals and producers.

For more insights into vaccination schedules and their importance, you might find this article helpful: Dog Vaccines & Boosters: How Often Does Your Dog Need Shots? While focused on dogs, it highlights the general principles of booster importance.

Proper administration is key to vaccine efficacy. This includes storing vaccines correctly, using clean needles, administering the correct dose, and following the recommended route (e.g., subcutaneous or intramuscular). Consulting with a veterinarian is essential to develop a tailored vaccination protocol for your specific herd and regional disease risks.

BRSV Vaccination Protocols and Best Practices

Developing an effective BRSV vaccination protocol requires careful planning and collaboration with your veterinarian. It’s not a one-size-fits-all solution, as factors like herd size, management practices, geographical location, and disease history all play a role.

Key Considerations for Vaccination Timing

The goal of BRSV vaccination is to provide protection when animals are most vulnerable. This typically means:

Calves: Vaccinating calves before they are exposed to the virus, especially prior to stressful events like weaning, commingling, or transportation. Maternal antibodies can interfere with vaccine effectiveness in very young calves, so timing needs to consider this. Many protocols involve a primary series followed by a booster.
Pregnant Cows/Heifers: Vaccinating dams can help transfer protective antibodies to their calves through colostrum (first milk). This passive immunity provides crucial early protection to newborn calves before they can develop their own immune response. Killed vaccines are typically preferred for pregnant animals.
Incoming Animals: New additions to the herd should be vaccinated and ideally isolated for a period to prevent introducing new pathogens.

Sample BRSV Vaccination Schedule for Calves

This is a generalized example. Your veterinarian will provide specific recommendations based on your farm’s unique situation and the vaccine products used.

Calf Age/Event	Vaccine Type (Example)	Purpose	Notes
Pre-weaning (e.g., 2-3 months old)	BRSV (MLV or KV) – First Dose	To initiate immune response before weaning stress.	Ensure calves are healthy. Avoid vaccinating stressed calves.
Weaning (e.g., 4-6 weeks after 1st dose)	BRSV (MLV or KV) – Booster Dose	To boost and solidify immunity. Crucial for robust protection.	Administer before or at weaning to protect during this high-stress period.
Pre-shipment/Sale (if applicable)	BRSV Booster (if timing allows)	To ensure peak immunity before commingling/transport.	Allow at least 2-3 weeks between vaccination and shipment for immunity to develop.
Adult Cows (Annually)	BRSV (KV, if pregnant; MLV if not)	To protect the cow and provide colostral immunity to calves.	Typically administered 4-8 weeks pre-calving for colostral transfer.

Integrating Vaccination into a Holistic Herd Health Plan

Vaccination is a powerful tool, but it’s most effective when part of a broader herd health strategy. A comprehensive plan should also include:

Biosecurity Measures: Preventing the introduction and spread of disease within the farm.
Nutrition: Ensuring calves receive adequate nutrition to support a strong immune system.
Stress Reduction: Minimizing stressors like overcrowding, poor ventilation, and abrupt changes in diet or environment.
Parasite Control: Internal and external parasites can weaken immunity, making animals more susceptible to BRSV.
Early Detection and Treatment: Regularly monitoring calves for signs of illness and promptly treating affected animals to prevent disease progression and spread.
Record Keeping: Maintaining accurate records of vaccinations, treatments, and animal health observations is vital for tracking efficacy and making informed decisions.

Working closely with your veterinarian to tailor these practices to your specific operation is paramount. They can help you select the most appropriate vaccines, determine optimal timing, and integrate BRSV prevention into a comprehensive health management program.

Beyond Vaccination: Holistic BRSV Prevention Strategies

While vaccination is the cornerstone of BRSV control, it’s not a standalone solution. A truly effective strategy involves a multi-faceted approach that addresses environmental factors, management practices, and overall animal well-being. This holistic approach maximizes the benefits of vaccination and minimizes the risk of outbreaks.

1. Biosecurity Measures

Preventing the introduction and spread of pathogens is fundamental to herd health. For BRSV, this means:

Isolation of New Animals: All new cattle entering the herd, especially calves, should be isolated for at least 3-4 weeks. During this period, monitor them for signs of illness and administer necessary vaccinations.
Controlling Traffic: Limit access to your farm by non-essential personnel and vehicles. Ensure visitors wear clean clothes and disinfect footwear.
Cleaning and Disinfection: Regularly clean and disinfect barns, stalls, feeding equipment, and water troughs, especially between groups of calves.
Separate Sick Animals: Promptly isolate any animal showing signs of respiratory illness to prevent further spread.

2. Optimizing Environmental Conditions

The environment plays a huge role in the transmission and severity of BRSV. Focus on:

Ventilation: Ensure adequate fresh air circulation in barns and calf housing. Good ventilation removes airborne pathogens, moisture, and noxious gases (like ammonia) that irritate respiratory tracts. Avoid drafts that can chill calves.
Space and Density: Prevent overcrowding. Providing ample space per calf reduces stress, minimizes direct contact, and lowers the concentration of airborne pathogens.
Bedding Management: Keep bedding dry and clean. Wet, soiled bedding harbors bacteria and creates an unhealthy environment.
Temperature Control: Protect calves from extreme temperature fluctuations, which can stress their immune systems.

3. Nutritional Management

A well-nourished calf has a stronger immune system, better equipped to fight off infections. Key nutritional aspects include:

Colostrum Management: Ensure newborn calves receive adequate high-quality colostrum within the first few hours of life. Colostrum provides essential maternal antibodies that offer passive immunity.
Balanced Diet: Provide a balanced diet appropriate for the calf’s age and stage of development, with sufficient energy, protein, vitamins, and minerals. Deficiencies can impair immune function.
Access to Clean Water: Constant access to fresh, clean water is crucial for overall health and hydration, especially for sick animals.

4. Stress Reduction

Stress is a major immunosuppressant. Minimizing stressors can significantly reduce BRSV susceptibility and severity:

Gradual Weaning: Implement gradual weaning strategies (e.g., fence-line weaning) to reduce the stress associated with separation from the dam.
Minimize Commingling: Avoid mixing calves from different sources or age groups whenever possible, as this increases exposure to various pathogens.
Gentle Handling: Reduce stress during handling, moving, and processing.
Consistent Routines: Maintain consistent feeding, watering, and handling routines to provide a stable environment.

5. Early Detection and Prompt Treatment

Even with the best prevention, some calves may still get sick. Early detection and treatment are vital to prevent disease progression and limit spread:

Daily Monitoring: Regularly observe calves for subtle signs of illness, such as reduced appetite, lethargy, or a slight cough.
Temperature Checks: Use a thermometer on suspicious calves.
Veterinary Consultation: Contact your veterinarian immediately if you suspect a BRSV outbreak or if calves show severe respiratory symptoms. Prompt diagnosis allows for targeted treatment and management adjustments.

By combining robust vaccination programs with these comprehensive management and biosecurity practices, producers can create a formidable defense against BRSV, leading to healthier calves, reduced economic losses, and improved animal welfare.

Real-World Impact and Success Stories of BRSV Prevention

The principles of BRSV prevention, particularly vaccination, are not just theoretical concepts; they have tangible, positive impacts on cattle operations worldwide. Producers who commit to comprehensive BRSV control strategies consistently report significant improvements in herd health and profitability.

Reduced Mortality and Morbidity

One of the most immediate and impactful benefits observed on farms with effective BRSV vaccination programs is a dramatic reduction in calf mortality. Where outbreaks once led to multiple deaths, vaccinated herds see far fewer fatalities. Beyond deaths, the overall sickness rate (morbidity) also drops significantly. This means fewer calves are sick, and those that do get ill experience milder symptoms, recover faster, and require less intensive treatment.

Improved Weight Gain and Performance

Healthy calves grow better. Farms that successfully control BRSV report improved daily weight gains and better feed conversion ratios. Calves aren’t expending energy fighting off disease; instead, they’re using it for growth and development. This translates directly into heavier calves at weaning or market, leading to increased revenue per animal. The stress of illness can stunt growth permanently, but preventing severe BRSV allows calves to reach their full genetic potential.

Lower Treatment Costs and Labor Savings

The financial burden of treating sick calves is substantial. Veterinary calls, antibiotic courses, anti-inflammatory drugs, and supportive care all add up. By preventing severe BRSV, producers drastically cut down on these expenses. Furthermore, the labor required to identify, isolate, treat, and monitor sick animals is significantly reduced. This frees up valuable time and resources that can be redirected to other productive farm activities, improving overall operational efficiency.

Consider a hypothetical scenario: A farm previously experienced a 10% mortality rate and a 30% morbidity rate from BRSV, costing thousands in treatments and lost production. After implementing a strict vaccination protocol and improving ventilation, the farm sees mortality drop to less than 1% and morbidity to under 5%. The savings in veterinary bills and increased calf weights quickly offset the cost of the vaccine program, demonstrating a clear return on investment.

Enhanced Animal Welfare and Producer Peace of Mind

Beyond the economics, the improved welfare of the animals is a profound benefit. Seeing fewer calves suffering from severe respiratory distress, coughing fits, and pneumonia brings immense relief to producers. A healthy, thriving herd is a source of pride and reduces the emotional toll that comes with managing widespread illness. This peace of mind, knowing that proactive steps are in place to protect the herd, is invaluable.

These real-world outcomes underscore that investing in BRSV prevention, centered around vaccination, is a smart, humane, and profitable decision for any cattle operation. It’s a testament to the power of scientific advancements in animal health when applied diligently and consistently.

Addressing Common Concerns and Myths about BRSV Vaccination

Despite the overwhelming evidence supporting BRSV vaccination, some producers may have questions or hold misconceptions. Addressing these concerns with clear, factual information is crucial for widespread adoption of effective prevention strategies.

Myth 1: “My calves look healthy, so I don’t need to vaccinate.”

Reality: This is a common and dangerous misconception. BRSV can spread rapidly and often silently before overt symptoms appear. By the time you see sick calves, the virus may have already infected a large portion of your herd. Vaccination is about *prevention*, not treatment. It builds immunity *before* exposure, ensuring calves are protected when the inevitable challenge comes. Waiting until calves show signs of illness is like waiting for your house to catch fire before buying insurance – it’s too late for effective prevention.

Myth 2: “Vaccines are too expensive.”

Reality: While there is an upfront cost to vaccination, it is a small investment compared to the potential losses from a BRSV outbreak. Consider the true cost of disease: veterinary bills, antibiotics, lost weight gain, increased labor, and potential calf deaths. When you factor in these expenses, vaccination consistently proves to be a highly cost-effective measure. Many studies and real-world farm data demonstrate a significant return on investment for vaccination programs due to healthier, more productive animals.

Myth 3: “Vaccines cause too many side effects.”

Reality: Modern BRSV vaccines are very safe. While any vaccine can potentially cause mild, temporary side effects (like a slight fever, lethargy, or a small swelling at the injection site), severe reactions are rare. The benefits of protection against a potentially deadly disease far outweigh these minimal risks. Reputable vaccine manufacturers adhere to strict safety standards, and adverse events are carefully monitored. Discuss any specific concerns about side effects with your veterinarian.

Myth 4: “Maternal antibodies from the cow will protect my calves.”

Reality: Maternal antibodies (passed through colostrum) provide crucial early protection, but their levels decline over time. This leaves a “window of susceptibility” when calves are no longer protected by maternal antibodies but have not yet developed their own active immunity. This window often coincides with the age when calves are most vulnerable to BRSV (e.g., 1-4 months). Vaccination helps to bridge this gap, ensuring continuous protection. Furthermore, the quality and quantity of colostrum can vary, making passive immunity unreliable as a sole defense.

Myth 5: “If I have good management, I don’t need vaccines.”

Reality: Excellent management practices (biosecurity, ventilation, nutrition, stress reduction) are absolutely essential and complement vaccination. However, they cannot replace the specific immune protection provided by vaccines. BRSV is highly contagious, and even with the best management, exposure can occur. Vaccination provides a critical layer of specific immunity that management practices alone cannot achieve. The most successful BRSV prevention programs integrate both vaccination and sound management.

Addressing these concerns with factual information empowers producers to make informed decisions that prioritize the health and profitability of their cattle operations. Trusting in scientific evidence and expert veterinary advice is key to overcoming these common myths.

Expert Recommendations and Future Outlook

The consensus among veterinary experts and animal health organizations is clear: BRSV vaccination is a non-negotiable component of a robust herd health program. Its proven efficacy in reducing disease severity, mortality, and economic losses makes it an indispensable tool for cattle producers.

Consult Your Veterinarian

The single most important recommendation is to work closely with your local veterinarian. They possess the expertise to:

Assess Your Farm’s Risk: Understand your specific management practices, historical disease challenges, and regional BRSV prevalence.
Tailor Vaccination Protocols: Select the most appropriate BRSV vaccine type (MLV vs. KV), determine optimal timing for primary and booster doses, and integrate it with other essential vaccines.
Advise on Administration: Provide guidance on proper vaccine handling, storage, and administration techniques to ensure maximum efficacy.
Develop a Holistic Health Plan: Help you implement comprehensive biosecurity, nutrition, and stress reduction strategies that complement vaccination.
Monitor and Adjust: Evaluate the effectiveness of your current program and make adjustments as needed based on herd health outcomes.

Your veterinarian is your most valuable partner in protecting your herd against BRSV and other diseases.

Ongoing Research and Future Developments

The field of animal health is continuously evolving. Researchers are constantly working to develop even more effective and user-friendly vaccines, improve diagnostic tools, and better understand the complex interactions of BRSV with other pathogens. Future developments may include:

Next-Generation Vaccines: Development of novel vaccine technologies that offer enhanced immunity, longer duration of protection, or easier administration.
Improved Diagnostics: Faster and more accurate on-farm diagnostic tests to identify BRSV quickly and guide treatment and control measures.
Genetic Resistance: Research into breeding cattle with increased natural resistance to BRSV, although this is a long-term endeavor.
Precision Animal Health: Utilizing data and technology to predict outbreaks and tailor interventions more precisely to individual animals or specific groups within a herd.

Staying informed about these advancements, often through your veterinarian, ensures that your farm benefits from the latest scientific knowledge and tools in disease prevention.

In conclusion, the threat of BRSV is real and significant, but it is also largely preventable. By embracing vaccination as a cornerstone of your herd health strategy, supported by sound management practices and expert veterinary guidance, you can protect your calves, safeguard your farm’s profitability, and ensure the welfare of your animals for years to come.

Frequently Asked Questions (FAQs) about BRSV and Vaccination

Q1: What is BRSV and why is it a concern for cattle farmers?

A1: BRSV stands for Bovine Respiratory Syncytial Virus. It’s a highly contagious virus that causes respiratory illness in cattle, especially young calves. It’s a major concern because it can lead to severe pneumonia, reduced growth, high treatment costs, and even death, causing significant economic losses for farmers.

Q2: How do calves usually get BRSV?

A2: Calves typically get BRSV through direct contact with infected cattle, often via airborne droplets from coughing and sneezing. It can spread very quickly in crowded conditions or when animals are stressed, such as during weaning or transport. Indirect spread through contaminated equipment is also possible but less common.

Q3: How does a BRSV vaccine protect my calves?

A3: A BRSV vaccine works by safely introducing a weakened or inactive form of the virus to the calf’s immune system. This “trains” the immune system to recognize the virus and produce protective antibodies. If the calf later encounters the actual BRSV, its immune system is ready to fight it off quickly, preventing severe illness or even infection altogether.

Q4: Are there different types of BRSV vaccines? Which one is best?

A4: Yes, there are Modified-Live Virus (MLV) vaccines and Killed Virus (KV) vaccines. MLV vaccines often provide stronger, longer-lasting immunity but might have specific usage restrictions (e.g., for pregnant animals). KV vaccines are generally safer for all animals but might require more booster shots. The “best” vaccine depends on your specific farm situation, herd health history, and veterinarian’s recommendation.

Q5: When should I vaccinate my calves against BRSV?

A5: Vaccination timing is crucial. Calves are typically vaccinated before stressful events like weaning or commingling, which increase their risk of exposure. Many protocols involve a primary dose followed by a booster shot a few weeks later. Pregnant cows can also be vaccinated to pass protective antibodies to their calves through colostrum. Always consult your veterinarian for a tailored vaccination schedule.

Q6: Can vaccination completely eliminate BRSV from my herd?

A6: Vaccination significantly reduces the risk of BRSV infection and greatly lessens the severity of disease if an animal does get infected. While it’s a powerful tool, it doesn’t guarantee 100% elimination of the virus from a farm, especially in high-traffic or high-stress environments. It works best as part of a comprehensive herd health plan that also includes good biosecurity, proper nutrition, and stress reduction.

Q7: Besides vaccination, what else can I do to prevent BRSV?

A7: Beyond vaccination, key prevention strategies include maintaining excellent biosecurity (isolating new animals, cleaning equipment), ensuring good ventilation in barns, avoiding overcrowding, providing proper nutrition, and minimizing stress during handling and weaning. Promptly isolating and treating any sick animals also helps prevent spread.