Stephanofilaria stilesi

Stephanofilaria spp.
Class	Nematoda
Super-family	Filarioidea

Stephanofilaira stilesi

Stephanofilaira stilesi
Class	Nematoda
Super-family	Filarioidea

Hosts

Intermediate hosts: The horn fly e.g Haematobia irritans

Definitive hosts: Cattle.

Identification

These small nematodes are between 3-6mm in lenth. The eggs have thin shells, and are around 65μm in length. The microfilaria are 50μm long and enclosed in a spherical, vitelline membrane.

Lifecycle

Horn flies feed on lesions found on the host skin, and ingest microfilariae, which later develop into L3. The definitive host is infected when the fly leaves the L3 on the host.

• The infective larvae develop in the horn fly - Haematobia irritans
  • Flies ingest microfilaria as they feed on cutaneous lesions.
  • Microfilaria develop into L3 larvae in the hornfly over 18-21 days.
  • Infective L3 larva are deposited into the skin when the fly bites again, where they grow into adult worms.