The gastrointestinal tracts of 60 raccoons (Procyon lotor) were examined for helminths. Six species were found: four species of nematodes (Arthrocephalus lotoris, Physaloptera rara, Gnathostoma procyonis, and Baylisascaris procyonis); one species of cestode (Mesocestoides variabilis); and one species of acanthocephalan (Macracanthorhynchus ingens). Baylisascaris procyonis has been implicated in the decline of woodrat populations throughout the northeast United States. As such, this parasite also may have been a factor in the extirpation of the eastern woodrat (Neotoma floridana) throughout most of southern Illinois. The frequency occurrence of Baylisascaris procyonis in our sample was unexpectedly low, 3 of 60 raccoons (5.0%), and suggests that reintroduction of eastern woodrats to formerly occupied sites in southern Illinois may not be adversely affected by this parasite.
Birch, Gary L., Feldhamer, George A. and Dyer, William G. "Helminths of the Gastrointestinal Tract of Raccoons in Southern Illinois with Management Implications of Baylisascaris procyonis Occurrence." (Jan 1994).