Prevalence of 'Giardia' spp. in Beaver and Muskrat Populations in Northeastern States and Minnesota: Detection of Intestinal Trophozoites at Necropsy Provides Greater Sensitivity than Detection of Cysts in Fecal Samples

摘要

Surveys on the prevalence of Giardia in animal populations have relied on the detection of cysts in fecal samples. The prevalence of Giardia in beaver and muskrat in four New England states plus Minnesota using both the detection of trophozoites in mucosal scrapings from live-trapped animals at necropsy, and/or by the detection of cysts in fecal samples collected from kill-trapped animals has been determined. In muskrats the prevalence of infection was 36.6% by cyst detection in fecal samples (N=790) from kill-trapped animals while infection was 95.9% in live-trapped muskrats when intestinal contents were analyzed for trophozoites (N=219). Similarly, in beavers, infection was 9.2% by cyst detection in fecal samples (N=662) from kill-trapped beavers whereas 13.7% of live-trapped animals (N=302) examined for trophozoites were infected. The detection of trophozoites in mucosal scrapings from live-trapped animals consistently yielded significantly higher prevalences for both muskrats and beavers than did detection of cysts in fecal samples. (Copyright (c) 1990 American Society for Microbiology.)