Bovine Brucellosis (Brucella): Causes, Symptoms, Diagnosis, Prevention & Control
Keywords targeted:
Bovine brucella, bovine brucellosis, brucella in cattle, brucellosis symptoms in cows, bovine brucella diagnosis, brucellosis prevention in cattle, dairy cattle diseases
Introduction to Bovine Brucellosis
Bovine Brucellosis is one of the most economically damaging and zoonotic diseases affecting dairy cattle and buffaloes worldwide. Caused primarily by Brucella abortus, this bacterial infection leads to abortion, infertility, reduced milk yield, and serious public health risks.
In India, where dairy farming is a backbone of rural livelihoods, bovine brucella infection often remains underdiagnosed, silently spreading within herds and causing long-term losses.
What is Bovine Brucella (Brucella abortus)?
Brucella abortus is a Gram-negative intracellular bacterium that primarily infects:
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Cattle
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Buffaloes
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Occasionally other livestock
It localizes in the reproductive organs, mammary glands, and lymph nodes, making it highly contagious within a herd.
How Brucellosis Spreads in Cattle
Brucellosis spreads through direct and indirect contact, especially during reproductive events.
Common Modes of Transmission
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Aborted fetus and placenta
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Uterine discharges after calving
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Contaminated feed, water, or bedding
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Infected milk and colostrum
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Natural service or infected semen
⚠️ One infected animal can infect an entire herd if biosecurity is weak.
Symptoms of Brucellosis in Cattle
In Female Cattle
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Late-term abortion (5–8 months of pregnancy)
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Retained placenta
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Infertility and repeat breeding
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Reduced milk yield
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Weak or dead calves
In Male Cattle
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Orchitis (swollen testicles)
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Reduced fertility
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Poor semen quality
Hidden Danger
Many animals become chronic carriers without visible symptoms, continuing to spread the disease.
Economic Impact of Bovine Brucellosis
Brucellosis causes direct and indirect financial losses, including:
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Loss of calves due to abortion
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Reduced lifetime milk production
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Increased breeding cycles
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Veterinary and management costs
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Trade and movement restrictions
Studies show brucellosis can reduce lifetime productivity of cattle by 15–25%.
Zoonotic Risk: Brucellosis in Humans
Bovine brucellosis is a serious zoonotic disease.
Humans can get infected through:
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Handling aborted materials without protection
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Consuming raw milk or unpasteurized dairy products
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Occupational exposure (farmers, vets, AI technicians)
Human symptoms include:
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Undulant fever
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Joint pain
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Chronic fatigue
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Muscle aches
Diagnosis of Bovine Brucellosis
Early and accurate diagnosis is critical for disease control.
Common Diagnostic Methods
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Rose Bengal Plate Test (RBPT)
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ELISA (i-ELISA, c-ELISA)
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Milk Ring Test (MRT)
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Rapid lateral flow diagnostic kits (on-field screening)
Regular screening enables early isolation and prevents herd-level outbreaks.
Treatment: Is Brucellosis Curable in Cattle?
❌ There is no effective treatment for bovine brucellosis.
Antibiotic therapy is not recommended due to:
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Poor efficacy
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High cost
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Risk of antimicrobial resistance
Infected animals should be isolated and managed as per veterinary and regulatory guidelines.
Prevention and Control of Brucellosis in Cattle
1. Vaccination
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Calfhood vaccination using S19 or RB51 vaccines
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Follow government-approved vaccination programs
2. Regular Testing
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Test new animals before introduction
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Periodic herd screening
3. Biosecurity Measures
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Proper disposal of aborted materials
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Disinfection of calving areas
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Separate calving pens
4. Milk Hygiene
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Avoid raw milk consumption
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Promote pasteurization
Role of Early Diagnosis in Brucellosis Control
Early detection:
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Prevents spread within herd
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Reduces economic losses
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Protects farm workers
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Improves reproductive efficiency
On-field rapid diagnostic tests are becoming a game-changer for rural dairy management.
Conclusion
Bovine Brucellosis is a silent but devastating disease affecting cattle health, farm economics, and human safety. With no curative treatment, prevention through vaccination, early diagnosis, and strict biosecurity remains the most effective strategy.
For sustainable dairy farming, regular brucella testing should be as routine as pregnancy diagnosis.
