Introduction

The bacterium Borrelia anserina infects chickens, turkey, geese, ducks, pheasants, grouse and canaries with morbidity and mortality up to 100%. It is transmitted by arthropods, e.g. Argas persicus, and occasionally by infected faeces. The bacterium is poorly resistant outside host but may be carried by Argas persicus for 430 days. Brachyspira pilosicoli, previously known as Serpulina pilosicoli, is an intestinal spirochaete that can be associated with inflammation of the large intestine in a broad range of mammals and birds. It has been associated with typhilitis, diarrhoea, reduced egg production, and egg soiling in chickens.

Signs

• Depression.
• Cyanosis.
• Thirst.
• Often diarrhoea with excessive urates.
• Weakness and progressive paralysis.
• Drops in egg production may be seen in both systemic and intestinal forms

Post-mortem lesions

• Marked splenomegaly.
• Spleen mottled with ecchymotic haemorrhages.
• Liver enlarged with small haemorrhages.
• Necrotic foci.
• Mucoid enteritis.

Diagnosis

Haematology, isolate in chicken eggs or chicks or poults.

Treatment

Various antibiotics including penicillin.

Prevention

Control vectors, vaccines in some countries.