Introduction

A bacterial infection, caused by Mycobacterium avium, of poultry, game birds, cage birds etc. Morbidity and mortality are high. Transmission is via faecal excretion, ingestion, inhalation, offal and fomites. The disease has a slow course through a flock. The bacterium resists heat, cold, water, dryness, pH changes and many disinfectants.

Signs

• Severe loss of weight with no loss of appetite.
• Pale comb.
• Diarrhoea.
• Lameness.
• Sporadic deaths.

Post-mortem lesions

• Emaciation.
• Grey to yellow nodules attached to intestine.
• Granulomas in liver, spleen and many other tissues, even bone marrow.

Diagnosis

Isolation, acid-fast stain in tissues, TB test. Differentiate from Lymphoid leukosis.

Treatment

None recommended.

Prevention

Market after one season, hygiene, cages, elimination of faeces etc.