Long nosed sucking louse

(Linognathus vituli)

This is the most common sucking louse in southern Australia, but is found in all states.

Type

Sucking louse, fine mouthparts puncture the skin to feed on cattle blood.

Adults

These are small lice with adults 2.5 mm in length, usually appearing bluish-black in colour with an almost black head. The name of this louse is derived from the shape of its head which is long and narrow and about twice as long as it is broad (Figure 1). Long nosed sucking lice are smaller and more slender than short-nosed sucking lice.

Figure 1. Long nosed sucking louse adult Linognathus vituli. Image credit Peter James
Figure 1. Long nosed sucking louse adult Linognathus vituli. Image credit Peter James

Eggs

0.9 – 1.1 mm long.

Location on animal

These lice tend to be found most commonly along the head, neck, dewlap and backline, but in heavier infestations during winter can be found on most parts of the body. They are found in clusters and a close search must be made of a number of areas on the skin before you can gauge how severe the infestation is. They are more commonly seen on calves and dairy stock and rarely occur in large numbers on mature animals.

Life cycle

The incubation period of the eggs of this species is 7-10 days and the complete life cycle from egg to adult takes 24-29 days. Females lay about one egg per day gluing it to a hair shaft close to the skin. They live about 42 days with the female laying up to 50 eggs in her lifetime.

Control

How and when to treat lice