Parasitology

Parasitology

Chewing v. Sucking Lice

At Greenwood it is necessary to find out whether it is a sucking or chewing species. Because they feed differently, they ingest different amounts of blood and must therefore be treated differently.

While pouch lice are a type of chewing lice, at Greenwood we consider them a third category as their treatment differs from normal chewing lice.

To identify the kind of lice, staff will put an adult louse under a microscope. The width of the head to the shoulders and jaw size are the distinguishing factors; chewing lice have a broader head with narrower thorax while the sucking lice have a narrower head with broader thorax. Pouch lice are easily identified by location on the host body. As the name implies, pouch lice are normally inside the mouth/pouch of a waterbird (especially pelicans).

Figure 4: Pouch lice in pelican pouch.