Raccoon Latrine Structure and Its Potential Role in Transmission of Baylisascaris procyonis to Vertebrates

Abstract

Baylisascaris procyonis, the common large roundworm of raccoons (Procyon lotor), causes clinical neurologic disease in many species of mammals and birds. Infective eggs of B. procyonis are present at raccoon latrine sites, and these sites may be important in the transmission of this parasite to syntopic small vertebrates in forested areas. We located raccoon latrines in forested sites in Indiana, sampled soil and fecal material from these locations, and examined these samples for the presence of Baylisascaris procyonis eggs. We also quantified the structural characteristics of raccoon latrines in wooded areas, compared their characteristics with randomly located sites, and classified sites based on structural features using stepwise discriminant function analysis. B. procyonis eggs were present at 14% of the raccoon latrines sampled. Latrine sites differed from randomly located sites and exhibited characteristics generally associated with treefall gaps. Most latrines were located either on logs (49%) or at the base of large trees (37%). Structural features surrounding latrines often are important travel routes or foraging areas for various small vertebrates. The visitation of mammals and birds to sites exhibiting these structural features may result in infection with B. procyonis. In this way, Baylisascaris procyonis could have long-term impacts on populations of native mammals and birds.