Date of Award
Master of Science
TITLE: PREVALENCE OF BAYLISASCARIS PROCYONIS AND IMPLICATIONS FOR MANAGEMENT OF EASTERN WOODRAT (NEOTOMA FLORIDANA) POPULATIONS Baylisascaris procyonis, a roundworm, is an endoparasite carried and spread by the ubiquitous raccoon, Procyon lotor. Raccoons are the definitive host of this parasite and normally do not experience mortality from being infected. However, accidental hosts include a wide range of animals from small rodents and birds to humans, and in these the parasite can cause brain damage and death. Infected raccoons can potentially release thousands of eggs in a single scat. The prevalence of B. procyonis in the raccoon population is a concern in areas where the endangered eastern woodrat (Neotoma floridana) occurs or has been reintroduced. The foraging strategies of woodrats make them particularly susceptible to infection. A high prevalence of the parasite could reduce population densities or negatively influence their successful reintroduction and long-term recovery. I established 10 transects in 4 areas of southeastern Illinois where woodrats have been reintroduced to gauge the abundance of this parasite and the possible implications for eastern woodrats. Latrine sites were visually located along these transects and raccoon scat piles sampled and analyzed using Fecalyzer flotation kits. Habitat variables were measured at each latrine site and compared to corresponding random sites to determine possible latrine site selection indicators. Four substrate types containing latrines were encountered: rock (n = 18), downed log (n = 13), leaf litter (n = 8), and live tree (n = 1). The amount of coarse woody debris was greater (t78=2.46, p<0.0088) at latrine sites (28.1%) than at random sites (16.6%). There was no difference in distance to a large tree at latrine vs. random sites. Seasonal variation in scat presence was apparent. The Garden of the Gods study site yielded the highest number of latrines and samples. Analysis yielded one fecal sample that tested positive for B. procyonis, out of 79 total samples (1.3%) . A comparison analysis was conducted at Randolph County Conservation Area, approximately 160 km west of the study area, which yielded a prevalence rate of 10%. The low rate of prevalence at the study area suggests that the parasite likely poses little risk to the reintroduced woodrat populations.
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