The occurrence of Fascioloides magna (Bassi, 1875) in the wild cervid population in the Lower Silesian Wilderness – epidemiological and pathological aspects

Abstract

Introduction Fascioloides magna is a parasite of high veterinary importance due to its pathogenicity for wild and domestic ruminants. The aim of our study was to describe the presence of trematode infection in the red deer population in the Lower Silesian Wilderness, one of the established fascioloidosis foci in Central Europe, and to assess the overall prevalence of F. magna in the studied area. In order to achieve this, a coprological study of different cervid species was performed. Material and Methods The livers of 99 red deer were collected over three years and examined for the presence of trematodes. Prevalence and infection intensity was estimated and a histopathological analysis was performed. In addition, 172 faecal samples from red deer, fallow deer and roe deer were examined. Results By year, Fascioloides magna was isolated from the livers of 2/30 (6.7%), 9/34 (26.5%) and 10/35 (28.6%) red deer. Severe hepatic lesions, including massive tissue damage, extensive fibrosis, and cirrhotic changes in the liver parenchyma were observed. Faecal examination revealed the presence of F. magna eggs, with a prevalence of approximately 40%, 50% and 53% in roe deer, fallow deer and red deer, respectively. Conclusion The eggs of F. magna may be commonly excreted in the faeces of roe deer, as well as those of red deer and fallow deer. The presence of F. magna throughout the cervid population in the Lower Silesian Wilderness favours the risk of the trematode’s transmission to livestock or farmed deer.

Identification and Molecular Characterization of Giant Liver Fluke (Fascioloides magna) Infection in European Fallow Deer (Dama dama) in Romania—First Report

“…Cervids originating from central Europe showed severe hepatic lesions in response to F. magna infection, as well as liver hypertrophy, and large areas of the liver surface on the diaphragm side were covered with fibrin [ 59 ]. The results of the present study revealed the presence of one to six pseudocysts that contained a hemorrhagic liquid and harbored 4–39 adult flukes with a length of 3.8–8.2 cm.…”

Hatchability of Fascioloides magna Eggs in Cervids

“…Our results supported a previous finding. The F. magna could be able to reach sexual maturity and produce fertile eggs in roe deer [ 6 ], whose species is currently known as the aberrant host. On the other hand, we confirmed that the parasite has the potential for selfing (self-fertilisation), which was previously observed in its relatives, within the order Echinostomida [ 12 , 13 ].…”

“…The signs of this possible co-evolutionary process can be detected. Within its older European habitats, faecal egg shedding is also confirmed [ 6 ], while it is lacking in newly invaded areas [ 5 ]. Pseudocyst formation in roe deer, as the sign of an advanced stage of infection, has already been found in all European F. magna habitats [ 15 ].…”

“…Fifty-two faecal samples were analysed to assess the prevalence and epidemiological risk of F. magna infection in roe deer [ 6 ]. The samples were collected in 2015 (n = 35) and 2017 (n = 17) in the Lower Silesian Wilderness, Poland.…”

“…These results demonstrated, on the one hand, that roe deer also could have a considerable role in the deposition of large American liver fluke eggs into the environment. On the other hand, the presence of the eggs in faecal material could indicate a co-evolutionary host–parasite relationship [ 6 ].…”