Oesophagostomum radiatum

Oesophagostomum radiatum Nodular Worm	Contents	Rev 10/17/2025
	Classification	Biology and Ecology
	Morphology and Anatomy	Life Cycle
Return to Oesophagostomum menu		Ecosystem Functions and Services
	Distribution	Management
Return to Chabertiidae Menu	Feeding	References
	Go to Nemaplex Main Menu	Go to Dictionary of Terminology

Classification

Phylum: Nematoda
Class: Chromadorea
Order: Rhabditida

Superfamily: Strongyloidea

Family: Chabertiidae

Subfamily Oesophagostominae

Oesophagostomum radiatum (Curtice, 1890) Stossich, 1899

Morphology and Anatomy:

Adults are white. .
Well-developed cervical alae. .
Cephalic region constricted behind the middle. No leaf crowns present but there is a ring of 38-40 small projections on the upper edge of the buccal capsule that may represent a vestigial leaf crown.

Females:

16-22 mm long and 300-400 um wide with a 300-400 um long tapering tail
Vulva quite posterior, 1 mm anterior to the anus
Eggs 72 x 38 um

Ref: Marchiondo et al., 2020

Males:

14-17 mm long and 300-400 um wide
Spicules 700-800 um long
Gubernaculum 100 um long, shovel-shaped with a telamon supporting structure near the cloacal aperture.

Reported median body size for this species (Length mm; width micrometers; weight micrograms) - Click:

Economic Importance:

A pathogenic parasite of the caecum and colon of cattle and buffalo. Most important in wet anmd warm tropical and subtropical regions of the world (Marchiondo et al., 2020)

Lifecycle is direct, no intermediate host. Eggs are deposited in feces. The L1 is probably microbivorous in the feces and molts to the L2 and then to the ensheathed infective L3 in 5-6 days. Infective L3 are present in pasture when moisture is present. The infective larvae are ingested by grazing cattle; they exsheath and enter the walls of the small and large intestine where they become encapsulated in nodules. They molt to L4 and enter an arrested (histotrophic phase) for 34 months. The L4 emerge from the nodules on to the surface of the mucosa and molt to the adult stage within 17-22 days of the initial infectrion. Adults mate and females produce eggs which are passsed in the feces. The prepatent period is 32-45 days (Marchiondo et al, 2020).

For Ecophysiological Parameters for this species, click	If species level data are not available, click for genus level parameters

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Damage:

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Management:

Topical and injected formulations of some anthelminthics are effective in cattle (Rehbein et al., 2022).

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References:

Marchiondo, A.A., Cruthers L.R., Reinemeyer, C.R. 2020. Nematoda, Strongyloidea. Chapter 2 in Marchiondo, Cruthers and Fourie (eds) Parasiticide Screening Vol 2. Academic Press.

Rehbein S., Hamel, D., Yoon, S., Johnson, C. 2022. Efficacy of eprinomectin topical solution and eprinomectin extended-release injection treatments against developing larval and adult Chabertia ovina and Oesophagostomum venulosum - two less common cattle nematode parasites. Veterinary Parasitology 312: 109837 https://doi.org/10.1016/j.vetpar.2022.109837

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