Dr. Murai Éva - Gubányi András szerk.: Parasitologia Hungarica 27. (Budapest, 1994)

at an early stage; thus, chronic lesions and mature flukes usually do not develop in these species (Stromberg et al. 1985a). Although potential egg shedding by sheep was described as an exceptional case (Campbell and Ibdd 1955), because of its rare occurrence this has, fortunately, no epizootiologic importance. Domestic swine react to F. magna infection in a manner similar to the wild boar. Although domestic animals rarely stay in areas visited by game, because of the mostly symptomless helminth-carrier status of game animals the infection may extend to large areas and, hence, it may occasionally pose a risk to domestic animals. As, apart from exceptional cases, no domestic animal species sheds eggs of the large American liver fluke in its faeces, by diagnostic faecal examination the infection of domestic animals cannot be demonstrated in vivo (Soulsby 1965). Despite the fact that liver flukes themselves are not strictly host specific (Foreyt and Todd 19766), in the United States F magna infection of deer is both epizootiologically and ecologically distinct from Fasciola hepatica infection of domestic animals, perhaps due to the fact that deer are indigenous on the American continent while domestic animals were introduced to it. Nevertheless, mixed fluke infections do occur in both host groups, but especially in cattle (Foreyt and Todd 1972). Since mixed infection may occur also in the European ungulate species which are of "chaotic" origin, in vivo diagnosis by coprological examination cannot always offer essential proof of the existence or absence of infection. The yellow fluke eggs shed by cervids cannot be differentiated with absolute certainty on a morphological basis and, as has been mentioned above, from domestic animals only the eggs of flukes belonging to the genus Fasciola can be demonstrated. In view of these facts, the prevalence of F magna can be monitored only by the regular examination of the liver and droppings of antlered game. Initially this does not appear to be a simple task, as the pathogen is insufficiently known in Hungary and because hunting as an activity is not aimed at surveying the health status of animals. It is difficult to make realistic predictions as to the future fate of F magna infection in Hungary; however, two premises can, and have to, be outlined. If the scope of free movement of the big game population, including the Szigetköz deer, will be restricted and individual stocks will become isolated from each other, a local increase of the fluke population can be reckoned with, as the risk of infection of snails will be higher within a given area. In that case F magna infection is likely to manifest itself in a clinically apparent form in big game. If, however, changes disturbing the living-space (e.g. in the Szigetköz area) lead to a more intensive movement and transmigration of trophied game, the inapparent form of infection may disperse throughout a large area. In that case there will be no local increase in the number of fluke eggs present in the droppings; hence, the risk of infection of snails will be lower, but the expanded scope of game movement will expose domestic animals to a risk of infection. F magna infection of the big game population entails unforeseeable consequences as to the condition of trophies. In Hungary this has outstanding importance, as our antlered big game (red deer, fallow deer, roe-deer) have long been known as animals carrying trophies which belong to the world's best as far as quality is concerned. Although F