Lice are often found on hens that are debilitated or unwell, and live their entire lives on the body of the host chicken; adult lice shun sunlight and will quickly scatter when feathers are parted. They cannot spread to humans or other species.
Lice live for one month and during this time a female louse will lay between 50 to 300 eggs. Adult lice are visible to the naked eye (3mm) and can usually be easily spotted running on the skin under the wings and around the base of the tail where they also lay their eggs in clusters. These clusters are very hard and difficult to remove without actually plucking out the feather (Figure 3).