The biting louse is an ectoparasite of birds and sometimes also mammals. Unlike ticks, lice are able to chew and survive on skin fragments, skin secretions, feathers, and hair instead of blood. Some species do feed on blood but it is mostly from existing wounds. Biting lice rarely have a significant adverse effect on their hosts directly, but can cause skin irritation and scratching. This can lead to open wounds on the host that can get infected.
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