Occurrence of the Giant Kidney Worm (Dioctophyma renale) in Long-Tailed Weasels (Mustela frenata) from Pennsylvania

Three adult giant kidney worms (Dioctophyma renale) were found in the right kidneys of two male long-tailed weasels (Mustela frenata) from Pike County, Pennsylvania. At necropsy, both weasels showed no clinical signs of decreased fitness. The right kidneys of both animals were enlarged and contained nematodes. This is the first described infection of long-tailed weasels by giant kidney worms in Pennsylvania. A more thorough investigation of long-tailed weasels across their range is recommended to determine prevalence rates of this parasite and potential impacts on weasel populations.