What it looks like
Lethargy and depression — Birds are inactive, unresponsive, and appear chronically ill
Ruffled feathers and huddling — Feathers appear fluffed; birds cluster together and move little
Diarrhea or watery droppings — Soft, watery, or greenish droppings
Respiratory signs (coughing, sneezing) — Mild to moderate respiratory signs; may include nasal discharge
Swollen joints or lameness — Difficulty walking; swelling in hock or other joints; bird may be unable to stand
Perihepatitis (liver inflammation visible at necropsy) — Fibrin coating on liver; visible during post-mortem examination
Sudden death or rapid decline — Bird appears healthy one day, severely ill or dead the next
Likely causes
- Infection with pathogenic strains of Escherichia coli (E. coli), gram-negative bacteria
- Ingestion of contaminated feed or water
- Inhalation of contaminated dust or aerosols (respiratory colibacillosis)
- Poor sanitation and overcrowding increasing transmission
- Stress (transport, vaccination, diet changes) triggering disease in carrier birds
What to do
Treat with broad-spectrum antibiotics (fluoroquinolone, aminoglycoside, or beta-lactam) under veterinary supervision. Antibiotic selection should ideally be based on culture and sensitivity testing. Follow label directions and withdrawal periods carefully. Provide supportive care: clean water, nutritious feed, and improved housing conditions. Manage secondary complications (arthritis, air sacculitis).
When to see a vet
See a vet if your bird shows severe signs or doesn’t improve within a few days of treatment.
Prevention
Maintain excellent sanitation: clean feeders/waterers daily, remove droppings regularly, disinfect housing. Avoid overcrowding. Quarantine new birds for 2-3 weeks. Minimize stress through good management. Prevent intestinal damage by avoiding wet litter and ammonia accumulation. Cull chronically infected birds to reduce transmission.
Frequently asked questions
What is colibacillosis?
Colibacillosis is infection caused by pathogenic E. coli strains. It can affect the respiratory tract (bronchitis), gastrointestinal tract (enteritis), joints (arthritis), or become systemic (septicemia, perihepatitis).
Is colibacillosis contagious?
Yes, contagious through contaminated environment (feces, dust, feed, water). Healthy birds can be carriers; stress or poor conditions trigger clinical disease in carriers and new infections in susceptible birds.
How is colibacillosis treated?
Antibiotics are the primary treatment. However, resistant strains are common; culture and sensitivity testing help guide drug selection. Supportive care and environmental improvements are essential for recovery.
Can E. coli kill chickens?
Yes, systemic colibacillosis (septicemia, perihepatitis) can be fatal, especially in young or stressed birds. Rapid recognition and aggressive treatment improve survival chances.
How do I prevent colibacillosis?
Maintain strict biosecurity and sanitation. Quarantine new birds. Minimize stress through good housing and management. Cull chronically infected birds. Manage litter moisture to reduce environmental contamination.