Haemonchus

Also known as:	Barber's pole worm
The most important veterinary species	Contortus

Scientific Classification

Kingdom	Animalia
Phylum	Platyhelminthes
Class	Trematoda
Subclass	Digenea
Order	Echinostomida
Family	Fasciolidae
Genus	Fasciola
Species	F. Hepatica

Introduction

Haemonchus contortus is a nematode parasite from the family Trichostrongyloidea. It is found worldwide, and is an extremely important parasite of sheep and goats, particularly in tropical/ subtropical regions.

Within the UK, it is found most commonly in the South, where the climate tends to be a little warmer and drier. Some have shown complete resistance to current anthelemintics which is posing a real problem, making sheep and goat farming extremely difficult in some areas of the country.

• Haemonchus contortus (abomasum) - sheep
  • 2cm long,barber's pole appearance when fresh
  • Primarily a tropical/sub-tropical parasite, although may cause problems in the UK (was restricted to SE England but has spread north to Scotland due to warmer, wetter winters in recent years)
  • Blood-sucking nematode (piercing "lancet" in buccal capsule of L4 and adult worms)