Commonly called the wire worm, this trichostrongyle nematode parasitizes sheep.

Life Cycle:
Unembryonated eggs are shed in the feces. After a day or two, first stage larvae hatch. The larvae feed on microorganisms in feces and develop to L2 larvae and then L3 larvae, which are still within the sheath of the L2 stage. L3 larvae are ingested with grass while grazing. The sheath is cast off in the definitive site, the abomasum; here the larvae molts two or three more times. In favorable conditions, adult worms develop and feed on the host's blood. Young adults (L4 larvae) can also take blood and cause anemia.

Clinical Signs:
Infected sheep have constipation (more often than diarrhea), weakness, lethargy, and pale mucus membranes. Infected animals are also anemic and may have bottle jaw and chronic weight loss. Heavy infections can be fatal.
Information from the article Haemonchus contortus - CVM

This page was last updated on: January 1, 2008
designed with Homestead
Barber Pole Worm
Haemonchus contortus