| 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. | surveys of the prevalence of the intestinal protozoan giardia spp. in animal populations have relied almost exclusively on the detection of cysts in fecal samples. we have determined the prevalence of giardia spp. in beaver and muskrat populations in four northeastern states and minnesota by using both the detection of trophozoites in mucosal scrapings from live-trapped animals at necropsy and the detection of cysts in fecal samples collected from kill-trapped animals. in muskrats the prevalence ... | 1990 | 2178552 |