Submitted to: Journal of Veterinary Diagnostic Investigation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/6/1999
Publication Date: N/A
Citation: Interpretive Summary: A parasitic worm (Capillaria hepatica) causes liver lesions and abnormal increase in certain blood cells (eosinophils) in humans. The parasite has been reported in numerous mammalian hosts throughout the world. In the USA, documented hosts of this parasite include the mouse, rat, vole, chipmunk, groundhog, squirrel, mole, shrew, opossum, weasel, fox, skunk, and raccoon. Infection of porcupines by the parasite has not been documented previously. A total of 53 adult porcupines (38 females and 15 males) were examined from State Gamelands No. 13 in northeastern Pennsylvania, USA. The parasites or their eggs were evident in the livers of 5 porcupines (1 male and 4 females). Livers of 6 additional animals exhibited characteristic track-like lesions caused by the parasite. However, the latter did not show the presence of the parasites or their eggs. Although Capillaria hepatica has been reported in many hosts in the northeast USA, infection of mammals that are exclusively vegetarian, has not been previously reported. Given that porcupines are primarily vegetarian feeders, finding Capillaria hepatica in the livers of the presently described porcupines was unexpected. However, it is conceivable that mature eggs of these parasites may have been present in the environment and that the porcupines could have ingested these eggs.
Technical Abstract: Tissues of 53 adult porcupines (Erethizon dorsatum) from Pennsylvania were obtained for histopathological examination. Hepatic capillariasis was recorded in 9% of the porcupines. An additional 11% of the liver sections showed lesions that were compatible with migration by Capillaria hepatica. As only 1 section of the liver per animal was examined microscopically, the documented prevalence of Capillaria hepatica in Pennsylvania is considered conservatively low. This condition, however, was sub-clinical, because none of the infected animals showed clinical signs, and none revealed severe pathological changes in the affected livers. This appears to be the only report of Capillaria hepatica in porcupines.