GIZZARD NEMATODES OF CANADA GEESE WINTERING IN SOUTHERN ILLINOIS

Gizzards from 64 hunter-shot Canada geese (Branta canadensis) were col lected in southern Illinois (USA) in December 1991 and January 1992 to determine the prevalence and intensity of gizzard nematodes. Three sp ecies of gizzard nematodes were recovered: Amidostomum anseris, Amidos tomum spatulatum, and Epomidiostomum crami. The prevalence of infectio n was 98%. Mean intensity was 17.8 nematodes per host and was signific antly greater for immature geese (40.3 nematodes/host) than for adult geese (10.9 nematodes/host). The intensity of both A. anseris and E. c rami was greater in immature geese, but even the most heavily infected birds did not display serious lesions. Despite a dramatic increase in the population of geese, mean intensity in adult geese was similar to mean intensity reported from earlier studies at the same site. Mean i ntensity in immature geese in 1991 and 1992 was greater than in earlie r studies.