Masters Thesis

Heligmosomoides polygyrus in Peromyscus.

The Nematode suborder Strongylata is among the most important groups of nematodes to man. In addition to two species of hookworms which infect millions of people in the world today, some 40 species of Strongyles infect domestic animals, causing considerable economic loss (Chandler and Read 1961). The Strongyles cause damage to their hosts by sucking blood. Most live in the digestive tract, but the species of 2 families, the Syngamidae and the Metastrongylidae, live as adults in the respiratory passages of their hosts. A few species in other families, for example the pig kidney worm, Stephanurus dentatus, of the Strongylidae, live in other exter-intestinal habitats.