Mastitis, an inflammation of the mammary gland, is a prevalent issue in the dairy industry, causing significant economic losses and affecting animal welfare. It occurs in clinical and subclinical forms, primarily due to bacterial infections like Staphylococcus aureus and Escherichia coli.
Effective management involves a blend of prevention and treatment strategies, including hygiene, bedding maintenance, milking practices, nutrition, and timely use of antibiotics. Early detection and a proactive approach ensure better herd health, minimized losses, and improved dairy product quality.
Key Takeaways:
| Aspect | Key Insights |
|---|---|
| Causes of Mastitis | Mainly bacterial infections (Staphylococcus aureus, Streptococcus agalactiae, etc.) through the teat canal. |
| Types | Clinical (visible symptoms) and Subclinical (no visible signs, detected via SCC). |
| Economic Impact | Losses due to reduced milk production, discarded milk, treatment costs, and premature culling. |
| Prevention | Hygiene during milking, clean bedding, proper nutrition, dry cow therapy, and well-maintained equipment. |
| Diagnosis | SCC, California Mastitis Test, and bacteriological culture to identify pathogens. |
| Treatment | Intramammary antibiotics, supportive care, and specific pathogen management. |
| Supportive Care | Pain relief, frequent milk removal, fluids, and proper veterinary care for severe cases. |
| Animal Welfare | Addressing pain and discomfort, reducing culling risks, and improving overall cow health. |
Understanding Mastitis
1. Causes of Mastitis
The primary cause of mastitis is bacterial infection, with various pathogens commonly involved. These include:
- Staphylococcus aureus
- Streptococcus agalactiae
- Escherichia coli
- Streptococcus uberis
- Klebsiella spp.
Other less common pathogens that can cause mastitis include Corynebacterium bovis, Mycoplasma spp., and Pseudomonas aeruginosa. Fungi, mycoplasma, viruses, physical injury, or chemical irritation can also cause mastitis. Pathogens typically enter the udder through the teat canal.
The origin of the pathogen often categorizes Mastitis:
- Contagious pathogens are spread from cow to cow, mainly during milking. These include Staphylococcus aureus, Streptococcus agalactiae, and Mycoplasma spp.
- Environmental pathogens reside in the cow’s environment, such as bedding, manure, and water. Examples include Escherichia coli, Klebsiella spp., Streptococcus uberis, and Streptococcus dysgalactiae.
2. Types of Mastitis
- Clinical Mastitis:
- Characterized by visible signs of inflammation, including swelling, heat, redness, and pain in the udder.
- Abnormal milk, which may appear watery, contain clots, flakes, or pus.
- Potential systemic signs, such as fever, anorexia, and lethargy.
- Subclinical Mastitis:
- Does not show visible symptoms but still impacts milk production and quality.
- Detected through elevated somatic cell counts (SCC).
Economic Impact of Mastitis
Mastitis results in significant economic losses for dairy producers, including:
- Reduced milk production
- Decreased milk quality, affecting cheese yields and shelf life
- Discarded milk due to mastitis or antibiotic treatment
- Increased treatment and veterinary costs
- Higher labor costs and decreased milking parlor efficiency
- Premature culling of infected cows
- Reduced fertility and higher risk of premature birth
Mastitis as an Animal Welfare Issue
Mastitis is also an animal welfare issue due to:
- Pain and discomfort experienced by cows
- Increased risk of culling
- Potential for severe cases and death
Prevention of Mastitis
Effective prevention of mastitis relies on a multifaceted approach, addressing various aspects of dairy herd management.
1. Milking Hygiene
Maintaining proper milking hygiene is crucial for mastitis prevention. This includes:
- Ensuring milking equipment is clean and well-maintained
- Pre-milking teat cleaning and disinfection:
- Using individual towels for each cow
- Adequately drying the teats
- Applying post-milking teat dips with germicidal properties
2. Bedding Management
Proper bedding management is vital to prevent mastitis:
- Maintaining clean and dry bedding to minimize pathogen growth
- Regular cleaning and replacement of bedding material
- Considering deep straw or sand bedding for better moisture management
3. Housing and Environmental Factors
- Ensuring proper ventilation in barns
- Minimizing mud and moisture in fields and cow tracks
- Reducing stress on cows to bolster their immune systems
4. Culling Chronic Cases
- Identifying and culling cows with recurring or chronic infections
- Focusing on cows infected with Staphylococcus aureus as they are more difficult to treat
5. Dry Cow Therapy
- Administering long-acting antibiotics at the end of lactation
- Treating existing infections and preventing new ones during the dry period
- Selective use of antibiotics at dry-off, as well as teat sealants
6. Nutrition
- Providing a balanced diet to maintain a strong immune system
- Ensuring adequate intake of vitamins and minerals
- Managing negative energy balance
7. Milking Equipment Function and Use
- Maintaining proper milk line vacuum and duration of milking
- Avoiding over-milking
- Ensuring adequate massage during milking
8. Other Management Practices
- Trimming long udder hair
- Using automatic backflush systems
- Ensuring proper cow flow to avoid injuries
9. Mycotoxin Management
- Monitoring feed for mycotoxins
- Incorporating mycotoxin counteracting products into the feed
Diagnosis of Mastitis
Accurate diagnosis is essential for effective mastitis management, as it helps identify the underlying cause and guide appropriate treatment.
1. Somatic Cell Count (SCC)
- SCC is an indicator of inflammation in the udder
- DHIA reports identify individual cows with subclinical mastitis
- Linear SCC scores help assess milk loss due to infection
- Bulk milk tank SCC (bSCC) is a herd-level indicator
2. California Mastitis Test (CMT)
- An on-farm test for early detection of mastitis
3. Bacteriological Culture
- Identifies specific pathogens to guide treatment
- Determines antibiotic resistance
- Newer near-cow diagnostic methods like the DairySmart system provide more immediate information
Treatment of Mastitis
Effective treatment of mastitis involves a combination of antibiotic therapy and supportive care.
1. Antibiotic Therapy
- Antibiotics eliminate the infection
- Intramammary infusions are the most common form of treatment
- Systemic antibiotics may be necessary for severe cases
- Following prescribed withdrawal periods is essential
- Select appropriate antibiotics based on culture results and antibiogram
- Prefer older, approved antibiotics for lactating cows
- Avoid antibiotics used for human medicine
- Consider dose frequency and duration
- Avoid injectable antibiotics when intramammary options are available
2. Treatment of Specific Pathogens
- Streptococcus agalactiae: High success rate with intramammary antibiotics
- Staphylococcus aureus:
- Target cows with new infections
- Cull chronically infected cows
- Segregate and milk infected cows last or with separate equipment
3. Supportive Care
- Monitor cows and provide pain relief
- Increase fluids and remove milk more frequently from the infected quarter
4. Treatment of Severe Cases
- Immediate veterinary attention
- Use of intravenous fluids and intensive care
5. First Aid Measures
- Applying ice to the udder surface
- Draining and safely disposing of infected milk
Conclusion
Prevention and early detection are crucial for effective mastitis control in dairy herds. An integrated approach using proper management and hygiene practices is key to reducing the incidence of mastitis. While antibiotics play a role in treatment, they should be used judiciously as part of a comprehensive control program.
By prioritizing prevention and implementing a proactive mastitis management strategy, dairy producers can safeguard the health and welfare of their cows, while also minimizing economic losses and ensuring the production of high-quality dairy products.
Table: Comparison of Mastitis Pathogens
| Pathogen | Transmission | Treatment |
|---|---|---|
| Staphylococcus aureus | Contagious | Target new infections; cull chronically infected cows |
| Streptococcus agalactiae | Contagious | High success rate with intramammary antibiotics |
| Escherichia coli | Environmental | Supportive care; antibiotics for severe cases |
| Streptococcus uberis | Environmental | Supportive care; antibiotics for severe cases |
| Klebsiella spp. | Environmental | Supportive care; antibiotics for severe cases |
