Strongyloidea

PARASITES NEMATODES

General Appearance

Strongyloides stercoralis - Courtesy of the Laboratory of Parasitology, University of Pennsylvania School of Veterinary Medicine

Strongyloides stercoralis - Joaquim Castellà Veterinary Parasitology Universitat Autònoma de Barcelona

Strongyloides larvae - Joaquim Castellà Veterinary Parasitology Universitat Autònoma de Barcelona

Strongyloides - Joaquim Castellà Veterinary Parasitology Universitat Autònoma de Barcelona

• Bursate
• Relatively short (typically 1-5cm) but stout
• Heads often have characteristic features

General Life-Cycle

• Like that of the trichostrongyloids (eggs are also 'typical strongyle eggs'), but:
  • L3 → L4 → adult (typically occurs in the large intestine)
  • Larvae penetrate the mucosal wall and elicit nodule formation
  • Larvae of some species migrate around the body
  • Prepatent period varies between species from 3 weeks to over 6 months

Strongylus vulgaris

Peritonitis in sheep by penetration of intestines by larvae of Oesophagostomum columbianum

Strongylus edentatus and Strongylus equinus migrate through Peritoneal Cavity Parasitic - Pathology

Stephanuris dentatus causes peritonitis in pigs Peritoneal Cavity Parasitic - Pathology and may cause cysts in the pancreas

Syngamus laryngeus in larynx of cattle