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Blackleg is an acute, highly fatal disease primarily affecting young, healthy cattle between 6 months and 2 years old. Caused by the spore-forming bacterium Clostridium chauvoei, this disease progresses rapidly, often leading to sudden death with few visible signs.
Since the spores can survive in soil for years, proactive vaccination and management are the only reliable defenses against this devastating condition.
Early detection of blackleg is extremely rare due to the rapid progression of the disease; often, sudden death is the first sign. However, recognizing the potential symptoms and environmental risk factors is crucial for minimizing herd losses.
When clinical signs do appear, they are severe and progress quickly. Common symptoms include:
Symptom | Symptom Description |
Acute Lameness | Usually the first noticeable sign, often affecting one leg (hind legs are common). |
Swelling and Crepitation | Characterized by hot, painful swelling in large muscle groups (shoulder, hip, back, neck). The swelling becomes spongy and emits a crackling sound (crepitation) when pressed, due to gas buildup beneath the skin. |
Systemic Distress | High fever, severe depression, anorexia (loss of appetite), and rapid breathing. |
Progression | The affected area quickly becomes cold, dry, and insensitive as tissue dies. Death typically occurs within 12 to 48 hours of symptoms appearing. |
The spores of Clostridium chauvoei lie dormant in muscle tissue until activated by an oxygen-deprived (anaerobic) environment.
Muscle Trauma: Bruising, excessive exercise, rough handling, or injuries can damage muscle tissue and reduce oxygen flow, triggering spore activation.
Age: Most vulnerable cattle are fast-growing calves from 6 to 24 months old.
Environmental Disturbance: Soil disturbance (e.g., excavation, flooding, erosion) can bring dormant spores to the surface, increasing ingestion risk during grazing.
Seasonal Conditions: Outbreaks are often seen in the summer and fall months, especially after heavy rains or in areas with moist, rich pastures.
Treatment of a clinically ill animal is rarely successful and is primarily limited to large doses of penicillin administered very early in the infection. Prevention through a rigorous, timely vaccination program is the only effective solution for blackleg in cattle.
Consult with your veterinarian to establish a comprehensive clostridial vaccine schedule. This program is the cornerstone of blackleg prevention.
Calves (Primary Series):
Vaccinate calves at 2 to 3 months of age.
Administer a booster dose 4 to 6 weeks after the initial vaccination.
Older Cattle (Annual Booster):
Administer an annual booster dose to all adult stock, ideally timed 2–4 weeks before the anticipated high-risk period (usually spring turnout).
For cows, giving the booster 2–6 weeks pre-calving provides maximum passive immunity transfer to the calf via colostrum.
Mitigate the risk of spore exposure and activation within your ag operation.
Carcass Disposal: Do not move or drag animals suspected of dying from blackleg. This spreads infectious spores. Deeply bury or incinerate the carcass where the animal died to limit soil contamination.
Pasture Management: Avoid grazing vulnerable animals on known blackleg endemic pastures, especially after heavy soil disturbance or flooding.
Handling Practices: Implement gentle handling and transport protocols to minimize bruising and muscle trauma in young stock.
Sanitation: Ensure surgical instruments (for castration or dehorning) are sterile and clean to prevent potential wound infections that can trigger clostridial diseases.
FBN provides a range of highly effective multivalent clostridial vaccines that include protection against Clostridium chauvoei, as well as other dangerous clostridial organisms (like C. septicum and C. novyi).
Product Name | Key Protection Areas | Shop on FBN.com |
Caliber® 7 | Blackleg, Malignant Edema, Black Disease, Gas-Gangrene, and Enterotoxemia (Types C/D) | |
Alpha-7® | Enterotoxemia (Pulpy Kidney / Overeating Disease), Blackleg, Necrotic Enteritis, Malignant Edema, Infectious Necrotic Hepatitis (Black Disease), Gas Gangrene | |
Bovilis® Vision® 7 with SPUR® | Enterotoxemia (Pulpy Kidney / Overeating Disease), Blackleg, Necrotic Enteritis, Malignant Edema, Infectious Necrotic Hepatitis (Black Disease), Gas Gangrene |
Note: Always read and follow the manufacturer's label directions for dosage, administration, and proper handling. Consult your local veterinarian before implementing any new vaccination strategy.
Protecting your herd from blackleg in cattle is a proactive effort centered on consistent, high-quality vaccination. By implementing a strict clostridial vaccine program and managing your pastures to minimize spore exposure, you can drastically reduce the risk of this fatal disease.
Visit FBN.com today to secure your vaccines and other essential animal health supplies.
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