Heterakis

HETERAKIS GALLINAE

• An atypical ascarid.
• Lives in the caeca.
• 1.5cm long, relatively slender and has a pointed tail. (Thus, it does not look like an ascarid, but is otherwise typical of the group).
• Eggs similar to those of Ascaridia.
• Life-cycle is non-migratory.
• Earthworms can act as transport hosts.
• This worm is not very pathogenic – its main importance is as the vector of Histomonas meleagridis, the protozoan parasite that causes 'blackhead'.
• Another species of Heterakis is a serious pathogen of pheasants. This burrows deeply into the caecal mucosa causing nodule formation, leading to weight-loss and death.