Occurrence and Pathogenicity of Heligmosomoides spp. (Nematoda: Heligmosomidae) Associated with Cecal Villi in Arvicolid Rodents

R. L. Rausch, University of Washington - Seattle Campus
M. L. Johnson, University of Puget Sound

Document Type Article

Published in Proceedings of the Helminthological Society of Washington 50(1). 1983. pp. 25-35

Abstract

The host response to the nematodes Heligmosomoides hudsoni (Cameron, 1937) and H. johnsoni Rausch and Rausch, 1973 (Heligmosomidae) was investigated in their natural hosts, varying lemmings, Dicrostonyx spp., and heather voles, Phenacomys intermedius Merriam (Rodentia: Arvicolidae) respectively. The nematodes occupy the cecum of the host, where they coil tightly around the long cecal villi. In individual animals, the comparatively few villi occupied became much enlarged, exhibiting severe hyperplasia of the mucosa and other microscopic changes, as described. The mechanism of pathogenesis involved three factors: strangulation of the villi, pressure atrophy, and chronic irritation by the crests of the synlophe. In lemmings, the presence of abundant plasma cells in affected villi indicated that H. hudsoni evokes a strong immune response. The distribution and zoogeography of the nematodes and their hosts are discussed.