Sika Deer (Cervus nippon) are not "Dead-End Hosts" of the Giant Liver Fluke, Fascioloides magna (Bassi, 1875) Ward, 1917.

Abstract

Fascioloides magna, although of North American origin, is well established in central Europe. Here it is expanding its geographic range and has been exposed to new potential final hosts including native and naturalized species. Based on their contribution to the propagation and transmission of F. magna, its final hosts have been grouped into three types including 'dead-end hosts' that comprise species in which flukes reach the liver but rarely mature and produce few eggs which are not excreted. Sika deer (Cervus nippon) were classified as dead-end hosts, this being quoted in the literature without robust substantiation. In an investigation on the occurrence of F. magna among sympatric wild ungulates in a recently established focus of the parasite in Germany, nine of 24 sika deer were found infected with up to seven F. magna in their livers, and six of the fluke-positive sika deer had Fascioloides eggs in their feces. Most flukes were recovered in pairs from fibrous capsules. Associated with the low fluke burden, gross pathology of the livers was generally mild. The presence of mature flukes in fibrous capsules, and passing of ova in the feces, demonstrates sika deer to be suitable definitive hosts of F. magna and to be of epidemiologic significance because of their implication in the transmission of the fluke.