Bovis ISSN 2398-2993

Haemonchus placei

Synonym(s): Haemonchosis, Barber’s Pole Worm

Contributor(s): Ash Phipps , Andrew Forbes




  • Phylum: nematoda.
  • Class: secernentea.
  • Subclass: rhabditia.
  • Family: trichostrongylidae.
  • Genus: haemonchus.
  • Species: H. placei.​

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Clinical Effects



  • Adults inhabit the abomasum.
  • Eggs are passed in the feces.
  • L1 and L2 inhabit the feces.
  • L3 inhabit the feces and surrounding herbage.


  • Prepatent period= approximately 28 days.
  • Direct lifecycle.
  • Adult worms produce eggs which are passed in the feces of cattle.
  • L1 hatch from the eggs within the feces.
  • L1 develop to L2 and L3 in the feces.
  • L3 are infective. 
  • Cattle ingest the L3 from the pasture.
  • The L3 larvae enter rumen and ex-sheath. 
  • The L3 undergo a further two moults in close proximity to the abomasal gastric glands.
    • Note: hypobiosis can occur in abomasal glands.  
  • Adults occupy the mucosal surface of the abomasum.


  • Ingestion of infective larval stage.

Pathological effects

  • Adult worms may consume 0.05ml blood per day. The clinical disease observed will be dependent on the host ability to compensate for blood loss and protein loss. Main mechanism for clinical disease is anaemia and hypoproteinemia. 
  • Acute presentation: severe anemia and/or sudden death.
  • Chronic presentation: poor growth, anorexia, anemia, bottle jaw and anasarca. 


Control via animal

  • Immunity can develop post infection and haemonchosis in cattle is mainly seen in young animals. 
    Keep cattle in a good plane of nutrition. 

Control via chemotherapies

  • The anthelmintic of choice will be dependent on the following:
    • Targeted species (for treatment of mixed nematode infections).
    • Presence of anthelmintic resistance on the farm.
  • The products available will vary depending on the country and include some flukicides, eg Closantel Closantel, rafoxanide & nitroxynil, in addition to the macrolides, benzimadazoles and Levamisole Levamisole.

Control via environment

  • Avoid overstocking pens and paddocks. 


  • No commercial vaccine for Haemochus placei is currently available. 
    • Trials have demonstrated potential for a vaccine to be developed to provide some protection against the nematode. 
    • Barbervax is commonly used in sheep and goats for protection against Haemonchus contortus.


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Further Reading


Refereed Papers

  • Recent references from PubMed and VetMed Resource.
  • Van Wyk J A & Mayhew E (2013) Morphological identification of parasitic nematode infective larvae of small ruminants and cattle: A practical lab guide. Onderstepoort Journal of Veterinary Research 80 (1), pp 1-14 PubMed.
  • Bassetto C C et al (2011) Protection of calves against Hemonchus placei and Hemonchus contortus after immunization with gut membrane proteins from H. contortus. Parasite Immunol 33 (7), pp 377-381.
  • Fabiyi J P, Copeman D B & Hutchinson G W (1988) Abundance and survival of infective larvae of the cattle nematodes Cooperia punctata, Haemonchus placei and Oesophagostomum radiatum from faecal pats in a wet tropical climate. Australian veterinary journal 65 (8), pp 229-231.

Other sources of information

  • Junquera P (2018) Haemochus spp, parasitic round worm of cattle, sheep, goats and swine. Biology, prevention and control. Haemonchus contortus, Haemonchus placei. Haemonchosis.. [online] Available at: Last accessed: 28 January 2018.
  • Parkinson T J, Vermunt J J & Malmo J (2010) In: Diseases of cattle in Australasia: a comprehensive textbook. New Zealand Veterinary Association Foundation for Continuing Education. pp 159, 729.
  • Anderson D E & Rings M (2008) In: Current Veterinary Therapy: Food Animal Practice. Elsevier Health Sciences. pp 80-81.
  • Radostits O M, Gay C C, Hinchcliff K W & Constable P D (2006) In: Veterinary Medicine: A textbook of the diseases of cattle, horses, sheep, pigs and goats. Elsevier Health Sciences. pp 1548-1551.
  • Foreyt W (2001) Veterinary Parasitology Reference manual. 5th Edn. Blackwell Publishing Company. pp 80.
  • Urquhart G, Armour A, Duncan J, Dunn A & Jennings F (1996) In: Veterinary Parasitology 2nd Edition. Blackwell Publishing Company. pp 19-22.