Trichostrongylus spp

From Rabbit
Adult Trichostrongylus worm

Trichostrongylus spp are a parasitic nematode roundworm of rabbits worldwide.

These nematodes have a direct life cycle and normally inhabit the cecum and large intestine of lagomorphs. Eggs are expelled through the host's faeces and shed into the environment approximately two weeks after the initial infection[1].

Species which are pathogenic to lagomorphs include:

  • Trichostrongylus retortaeformis (European rabbit)[2][3]

Infection rates in rabbits vary seasonally and as well as influenced by the rabbit's age. Higher burdens are apparent in younger rabbits in summer months[4]. The parasite also has a tendency to migrate into the intestinal mucosa during the initial establishment phase, causing enteritis which may be mild enough to avoid detection clinically[5].

Most infections are asymptomatic but heavy burdens may cause syphlitis and anemia.

Treatment is usually effective with fenbendazole or ivermectin.


  1. Audebert F et al (2002) Life cycle of Trichostrongylus retortaeformis in its natural host, the rabbit (Oryctolagus cuniculus). J Helminthol 76:189–192
  2. Cornell SJ et al (2008) Seasonality, cohort-dependence and the development of immunity in a natural host-nematode system. Proc Biol Sci 275(1634):511-518
  3. Murphy L et al (2011) Explaining patterns of infection in free-living populations using laboratory immune experiments. Parasite Immunol 33(5):287-302
  4. Cattadori IM et al (2005) Immuno-epidemiology and peak shift in a seasonal host–nematode system. Proc R Soc B 272:1167–1169
  5. Audebert F et al (2003) Intestinal migrations of Trichostrongylus retortaeformis (Trichostrongylina, Trichostrongylidea) in the rabbit. Vet Parasitol 112:131–146