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

tissue proliferation proceeded along either the blood vessels or the bile ducts. The nut-sized foci seen in the liver proved to be connective tissue cysts of 3-5 mm wall thickness. The wall of the cyst became inseparably attached to the parenchyma, and its lumen was filled with a reddish-brown to blackish-brown, slightly granular substance of indistinct structure and resembling a blood clot in consistency. Each of these cysts was at least 3-4 cm in diameter; they often formed coalescing lacunae and were grouped primarily around the hepatic portal. Because of the coalescence, the exact number of the cysts could not be determined. While the majority of the cysts contained only the necrotic debris described above, from some of them flukes of large size could be squeezed out. The lumen of the cysts communicated with the larger bile ducts. A total of 10 flukes could be collected from the liver. The flukes occurred exclusively within the cysts, and at least 6 specimens were seen in the cyst lumen in pairs. The absence of the gallbladder prevented us from examining its content. All of the large flukes removed from the liver belonged to the species F magna. The liver contained no other flukes or other parasite species. Some measurements of the flukes removed from the liver are shown in Table 1. Only one of the flukes, the biggest specimen, had a shape typical of adult F. magna, i.e. having a rounded tail end and a blunt cephalic end. The other specimens were more slender and had more tapered ends, thus resembled the fluke Fasciola gigantica in shape but were thicker than that. None of the animals contained mature eggs, and such eggs could neither be demonstrated from the tissue debris present in the cysts seen in the liver. The helminths' multibranched intestines were filled with a reddish-brown substance similar to the tissue debris present in the liver cysts. The intestinal branches around the oral sucker displayed the fine ramification typical of the species, which could be used for distinguishing the species from members of the genus Fasciola. Although the sexual organs, including the vitellaria, were at a stage preceding full development even in the biggest fluke specimen, in histological sections of the helminths it could be demonstrated that vitellaria developed only on the ventral side of the caecal branches, as opposed to Fasciola hepatica and Fasciola gigantica in which they develop both ventrally and dorsally. The opercular suture was clearly distinguishable on the colourless, oval-shaped, 178-180 um long eggs collected from the uterus of the biggest fluke specimen; however, the egg-shell thickening characteristic of mature eggs was not yet discernible. Thin-walled eggs tended to undergo deformation; many of them had a tapering, deformed operculum. Prompted by the fact that we found such a severe infection in a single hind bagged at random, we wished to determine the prevalence of F magna infection in deer living in the Szigetköz region. Therefore, we asked game wardens to collect deer droppings for parasitological examination. In mid-April 1994,15 such samples were collected in the region of Dunaremete and Lipót. The samples were processed by routine parasitological examination methods used at the Central Veterinary Institute. Using a 5-gram amount of sample, we performed coprological examination using Benedek's egg enrichment by sedimentation and a combined zinc sulphate floatation procedure (Majoros 1986, Nemeséri and Holló 1972). As all the samples were derived from deer