Lice

Anopluran - Sucking Lice

Anopluran lice are found only on placental mammals. They feed on the blood of hosts via their piercing mouth parts, consisting of three stylets, and thus have been dubbed "sucking lice."  Example genera include Haematopinus, Linognathus, Solenoptes, Polyplax, Pediculus, and Phthirus.

Anopluran lice
Adult lice and nits of the suborder Anoplura as seen on their host.

Haematopinus sp.
A genus of sucking lice that infests pigs, cattle, horses, and other species.

Haematopinus sp.
Nits (eggs) attached to hairs.

Haematopinus eurysternus Also known as the short-nosed cattle louse, Haematopinus eurysternus is considered to be the most economically important louse of cattle. They are usually found on the top of the neck, base of the horns, brisket, and tips of the ears, but may be found anywhere when an animal is heavily infested.

Haematopinus suis
Haematopinus suis adults feeding on a pig. The largest species of louse to infect domestic animals, Haematopinus suis, or the hog louse as it is commonly known, is an obligate ectoparasite of wild and domestic swine. A known carrier of Swine Pox, the hog louse is associated with intense pruritis and often confused with mange.

Haematopinus quadripertusus
Haematopinus quadripertusus nymphs on the vulva of an adult cow. Haematopinus quadripertusus adults are found almost exclusively in the hair at the end of cattle tails, lending their common name the 'tail-switch louse.' They lay their nits on tail heads and switches. Upon hatching, nymphs migrate to the soft skin around the anus, vulva, and eyes. Once they molt, they migrate one more time back to the tail switch.

Linognathus sp.
A genus of sucking lice that infests sheep, cattle, and dogs.

Pediculus humanus
Pediculus humanus is comprised of two subpecies, Pediculus humanus humanus (body louse) and Pediculus humanus capitis (head louse).

Polyplax spinulosa
A common louse of rats, Polyplax spinulosa, or spined rat louse, can be found on domestic, laboratory, and wild rats. It is a biological vector for Haemobartonella muris in addition to causing host pruritus and alopecia.

Phthirus pubis
Known as the pubic louse or crab louse, Phthirus pubis infests only humans. Lice are extremely host specific and Phthirus pubis is not known to survive and reproduce on pets or other animals. A related species, Phthirus gorillae, has been described from mountain gorillas.
Photo by Brian Herrin, Kansas State University

Solenopotes capillatus
Also known as the little blue cattle louse, Solenoptes capillatus is preferentially found on the face and jaw of captive ungulates, namely cattle and gazelles. They are spread through direct contact.

Mallophagan - Chewing Lice

Mallophagan or "chewing lice" are found on both birds and mammals, ingesting skin, keratin from feathers or hair, and secretions of their hosts. Three suborders are described - Ischnocera (e.g. Damalinia spp.), Amblycera (e.g. Gliricola spp.), and Rhynchophthirina (Haematomyzus spp.).

Damalinia bovis
A common chewing louse of cattle is Damalinia bovis. They may be found in greater numbers on cattle during the winter and early spring when cattle are in closer proximity and have longer hair coats. ​

Damalinia caprae
The most common louse of goats, Damalinia (Bovicola) caprae preferentially inhabits the lumbar area and back of shorter haired goats.

Damalinia caprae
Adults (blue arrow) and nits (black arrow) of Damalinia (Bovicola) caprae on the back of a goat.

Damalinia equi
The chewing louse of horses, Damalinia (Bovicola) equi has a predilection for the neck and tail head. Outbreaks are more likely to occur during the winter time and clinical signs include pruritus, alopecia, and scaly skin.

Felicola subrostrata
The chewing louse of cats. This louse is easily recognizable because the head is triangular-shaped.

Menopon sp.
Genus of chewing lice commonly found on birds.

Trichodectes canis The canine biting louse is about 1.5 millimeters in length and can be visualized without magnification.

Trichodectes canis
Cleared specimen of adult Trichodectes canis.

Trichodectes pinguis
Adult Trichodectes pinguis, the chewing louse of black bears.