Is there competition between Haemonchus contortus and Haemonchus placei in a pasture grazed by only sheep?

In conclusion, hybridization between H. contortus and H. placei can occur in the field during coinfection. It was demonstrated that H. placei established successfully in artificially infected worm-free sheep; however, with concomitant natural reinfection with H. contortus, the H. placei population showed a rapid decrease and was eliminated within a few months in an environment without cattle.
Source: Veterinary Parasitology - Category: Veterinary Research Source Type: research