Introduction

A condition occurring worldwide in chickens, especially caged layers and with a complex set of causes including excessive calories, mycotoxins, deficiency and stress.

Signs

• Overweight typically by 25%.
• Sudden death.
• Sudden drop in egg production.
• Some birds with pale comb and wattles.

Post-mortem lesions

• Obesity.
• Headparts pale.
• Liver yellow, greasy and soft with numerous haemorrhages.
• Death by internal exsanguination after rupture of haematocyst.

Diagnosis

Lesions, history.

Treatment

Reduce energy intake, supplement with choline, vitamin E, B₁₂ and inositol.

Prevention

Feed to avoid obesity, avoid mycotoxins and stress.