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

美国东北部各州和明尼苏达州海狸和麝鼠种群中贾第鞭毛虫的流行情况：尸检中肠道滋养体的检测比粪便样本中包囊的检测具有更高的灵敏度