External Parasites or Lice on Chickens and Other Poultry.

There are several types of biting lice that effect chickens and other poultry. These are known as ectoparasites or external parasites as they live on the outside of the bird. They range in size from about 1 to 4mm and can be found crawling on the bird at the base of the feathers, spreading from bird to bird by direct contact. Off the bird lice can survive for a few days so although less likely, can also spread from bird to bird via the hen house or litter. Most chickens will have a few lice on them from time to time but it's important not to let the numbers get out of control.

Signs of Lice

• 1 to 4mm fast moving lice at the base of the feathers.
• Lice eggs stuck to the feathers.
• A drop in the number of eggs laid.
• Irritation, scratching and in severe cases, anaemia.

Preventing Lice

Avoid contact with birds that have lice, provide a dust bath to help chickens and other poultry rid themselves of lice. Diatomaceous Earth can be added to the dust bath which will help.

Treating Lice

Powders containing the Pyrethrium are usually effective (when approved for application to birds) some organic powders contain tea tree and other ingredients that the lice don't like. Diatomaceous Earth like diatom can be effective with a few treatments, this works by drying the lice up but getting the bird dusted all over can be difficult. It is sometimes useful to add these powders to nesting areas, bedding and into dust baths (in the case of chickens, turkeys and guinea fowl) so that birds can effectively apply these themselves.
The life cycle of biting lice is around 3 weeks - so it is important when using a product to remove them that you re-check regularly and re-treat as necessary after a week as most products will not kill the eggs and these will hatch over this period.