Chewing Lice

Bovicola (Damalinia) bovis

(cattle biting louse, red louse)

Length ~2 mm

Most commonly found on dorsum.

Infestations may extend cranially to head and caudally to tailhead.

Bloodsucking Lice

Linognathus vituli

(long-nosed cattle louse)

Length ~2.4 mm in females, ~1.8 mm in males

Head and body elongated

Color: bluish

Most commonly found over withers, lateral shoulders, and dewlap.

May have generalized distribution over animal.

In early infestations, may be found in clusters.

In heavy infestations, may be found over most of body.

Solenopotes capillatus

(little blue cattle louse)

Length ~1.5 mm in females, ~1.1 mm in males

Can be mistaken for L vituli nymphs; however, head and body are less elongated

Found in distinct clusters, mainly on head and face.

Heavy infestations may extend to dewlap or surround eyes.

Haematopinus eurysternus

(short-nosed cattle louse)

Length ~2.9 mm in females, ~2.3 mm in males

Often found on front half of host from ears to dewlap.

Infestations tend to be heavier in cranial portions of body, including ears, during warm weather.

Haematopinus quadripertusus

(cattle tail louse)

Large louse: length ~4.0 mm in females, ~3.2 mm in males

Adults often confined to tail; eggs commonly noted on tail switch.