Bovine Lungworm (Husk): Welfare and Prevention

Key Facts

• Lungworm larvae are ingested from pasture and develop in the lungs, causing coughing and respiratory distress
• First-season grazers are most severely affected — naive animals lack acquired immunity
• The characteristic 'husk' cough can be heard across a field — a clear welfare indicator
• Severe infections cause bronchopneumonia, secondary bacterial pneumonia, and deaths
• Oral anthelmintic vaccines (Dictol) given 6 weeks before first grazing provide solid protection

Welfare Considerations

Bovine lungworm causes intense respiratory suffering. The coughing is violent, frequent, and exhausting — affected cattle may cough continuously for minutes at a time. Secondary bacterial pneumonia complicates many cases, adding fever and systemic illness to the respiratory distress. Welfare-centered management requires prompt anthelmintic treatment (macrocyclic lactones, benzimidazoles) combined with NSAIDs for anti-inflammatory and analgesic effects. Prevention through vaccination of naive cattle before their first grazing season is highly effective and eliminates most welfare suffering from this condition.

What You Can Do

• Vaccinate naive cattle with oral lungworm vaccine 6 weeks before their first grazing season
• Monitor first-season grazers for coughing — early intervention before severe pneumonia develops is critical
• Treat all confirmed lungworm cases with anthelmintic plus NSAID combination for welfare and recovery
• Avoid high-risk pastures (known larvae challenge) for naive first-season grazers where possible
• House severely affected cattle to reduce stress and facilitate recovery and nursing care