Introduction

Some coronaviruses involved in this condition are considered to be bovine coronaviruses (or closely related thereto); others are avian coronaviruses closely related to infectious bronchitis virus. The infection is seen in turkeys and sometimes pheasants. Morbidity is close to 100% and mortality is 5-100%. Transmission is lateral with birds and faeces, with rapid spread. The course of the disease is about 2 weeks and birds then remain carriers for months. The viruses survive in frozen faeces for months.

Signs

• Anorexia.
• Depression.
• Frothy diarrhoea.
• Subnormal body temperature.
• Darkening of the head.
• Loss of weight.
• Huddling.

Post-mortem lesions

• Dehydration.
• Emaciation.
• Enteritis with petechial haemorrhages.
• Froth ingesta.
• Sometimes casts.
• Pancreas chalky.
• Urates in kidneys/ureters.

Diagnosis

Reproduction with filtered contents, isolation in turkey eggs, electron microscopy, immuno-fluorescence, Elisa. Commercial M4I IB Elisa will detect some infections.

Treatment

Warmth and good management, antibiotics, milk replacer, potassium chloride. Disinfect and rest houses for 3-4 weeks.

Prevention

All-in/all-out production, good hygiene and biosecurity, good management.