Studies on the Pathology of Dicrocoeliasis and Fascioliasis in the Goat I. The Histopathology of the Liver and Bile Ducts

Abstract

Comparative studies were made on the histopathology of the liver and bile ducts in dicrocoeliasis and fascioliasis of the goat. Investigations revealed certain similarities in the nature of the pathological phenomena produced by D. dendriticum and F. hepatica. However, a feature peculiar to fascioliasis was the migratory tracks of immature flukes in the liver parenchyma. Further, the lesions produced by fascioliasis were distinctly more pronounced than those present in dicrocoeliasis.

In both parasitic diseases the bile-duct walls showed glandular hyperplasia, increased frequency of goblet cells and globule leucocytes, and extensive fibrosis in the outer layers. The desquamation produced by Dicrocoelium remained superficial whereas Fasciola was capable of causing deep erosions in the walls of the main bile ducts. The bile-duct walls did not become calcified. Increased fibrosis was present in the interlobular areas, too, but only fascioliasis produced extensive disorganisation of the hepatic architecture, due to the scars originating from repaired migratory tracks. The liver parenchymal cells were degenerated, showed decreased glycogen but were increasingly infiltrated by neutral fats.

Sammanfattning

Jämförande undersökningar har utförts med avseende på leverns och gallgångarnas histopatologi vid dicrocoeliasis och fascioliasis hos get. Fynden visade en del likheter hos de patologiska förändringarna orsakade av D. dendriticum och F. hepatica. Fascioliasis visade i motsats till dicrocoeliasis karakteristiska migrationsgångar i leverpar enkymet orsakade av omogna leverf lundror. Skadorna orsakade av fascioliasis var dessutom mer prononcerade än vid dicrocoeliasis.

Hos vardera parasitära sjukdom visade gallgångsväggarna en körtelaktig hyperplasi, ökad frekvens av hägarceller och globule leukocyter och prononcerad fibrös i perifera skikt. Av Dicrocoelium orsakade deskvamationer var superficiella medan Fasciola visade djupgående erosioner i väggarna hos de stora gallgångarna. Förkalkningar observerades dock inte, ökad fibrös påvisades i de interlobulär områdena men en prononcerad desorganisation observerades endast vid fascioliasis orsakad av ärrbildningar utgående från helnade migrationsgångar. Levercellerna var ofta degenererade och visade minskad glykogenhalt och infiltration med neutralt fett i tilltagande mängder.