UK - The term avian intestinal spirochaetosis (AIS) refers to disease in chickens and sometimes other avian species
associated with the presence of Brachyspira species spirochaetes in the large intestine, according to the Animal Health
and Veterinary Laboratories Agency in their Veterinary Information Note.
Clinical Signs
In the UK the disease is mainly seen in layer chickens from approximately 20 weeks of age onwards, in which there are mild to
moderate clinical signs typically including diarrhoea (particularly slimy or slightly frothy, caramel coloured droppings), pasty
vents, faecal staining of egg shells and a drop in egg production, and the birds may appear lethargic.
