Volume 51, Issue 2

Rediae and immature cercariae of the giant liver fluke, Fascioloides magna, a pathogenic and important parasite of game animals, were found in 6 out of 7,277 Radix peregra (Gastropoda, Lymnaeidae) from two localities in Western and Central Bohemia, Czech Republic. In one of these localities a relatively high infection of Galba truncatula (26 out of 76) with mature cercariae of F. magna was detected. R. peregra, which is dominant over Galba truncatula, has never been reported as the natural intermediate host of F. magna. Its potential susceptibility to F. magna infection was confirmed experimentally with 67 snails of R. peregra (out of 371) infected. The present data indicate the capability of F. magna to expand the spectrum of its intermediate hosts and demonstrate the potential epizootiological importance of lymnaeid snails, other than G. truncatula, for transmission of the parasite in Europe.

This study reviews the taxonomy of anoplocephaline cestodes of wood rats, Neotoma cinerea, N. fuscipes and N. mexicana (Sigmodontinae) in the western and south-western U.S.A. The anoplocephaline fauna included five species, only one of which, Andrya neotomae Voge, 1946, was relatively common and occurred in all three host species. Other species were Paranoplocephala freemani Haukisalmi, Henttonen et Hardman, 2006, P. primordialis (Douthitt, 1915), both host-generalist species of North American rodents, and two apparently undescribed species of Paranoplocephala s. str. Aprostatandrya octodonensis Babero et Cattan, 1975 from the indigenous South American rodent Octodon degus is regarded as a junior synonym of A. neotomae. A redescription is provided for A. neotomae.

The distribution patterns and the cestode species interactions within the spiral intestine of 20 specimens of Mustelus schmitti from coastal waters off Mar del Plata, Argentina were studied. Six cestode species were found: Tetraphyllideans Calliobothrium barbarae, C. australis, C. lunae and Orygmatobothrium schmittii, diphyllidean Echinobothrium notoguidoi and trypanorhynch Eutetrarhynchus vooremi. The most common number of parasite species per host was 3. Brillouin’s diversity index ranged from 0.1 to 1.2 Berger-Parker dominance index indicated that C. barbarae was the dominant species, followed by O. schmittii and C. australis. Calliobothrium barbarae, C. australis and O. schmittii presented a broad distribution along the spiral intestine, whereas C. lunae, E. notoguidoi and E. vooremi showed a more restricted niche breadth. In general, the Renkonen’s index showed no evidence of niche overlap in the range of distribution of the different species. In most of the infracommunities, intraspecific aggregation was stronger than interspecific aggregation, indicating that competition may play a little role. The distribution patterns of the Calliobothrium specimens concurs with the predictions of attachment sites for Calliobothrium species made by previous authors.

The extensive distribution of Echinococcus multilocularis cestode from endemic alpine areas to the parts of Central Europe has been recorded in recent years. The first confirmed finding of E. multilocularis in Slovakia was recorded in 1999 in the area adjacent to the Polish border. At present, this serious zoonosis occurs almost across the whole territory of Slovakia. The occurrence of these tapeworms in red foxes (Vulpes vulpes) at the border regions of Slovakia and Poland has been monitored. In these districts, out of 152 faecal samples examined, 36.2% were positive for the coproantigen-ELISA. With the sedimentation and counting technique the prevalence of E. multilocularis in red foxes was up to 38.8%. The examination of foxes from neighbouring districts revealed worm burden ranging from 1–15,000 specimens, but the majority of animals harboured medium number of tapeworms. In the Small Carpathian and Sub-Carpathian regions of Poland, out of 65 samples examined, 13.8% were coproantigen positive. Using the small intestine scraping method only 6.1% prevalence of E. multilocularis in red foxes was determined, mostly with a high worm burdens over 1,000 specimens. The results suggest possible transborder transmission of E. multilocularis, the causative agent of serious alveolar echinococcosis.

Gravid or subgravid females of the following three species belonging to the nematode genus Philometra were collected from marine perciform fishes of the Bonifacio Strait Marine Reserve, Corsica, France: Philometra justinei sp. nov. (prevalence 1.5%, intensity 11) and Philometra sp. (prevalence 3%, intensity 2) from the abdominal cavity and gonads, respectively, of the striped red mullet Mullus surmuletus (Mullidae), and Philometra serranellicabrillae Janiszewska, 1949 (prevalence 27%, intensity 2–6) from the gonads of the comber Serranus cabrilla (Serranidae). The newly described species, P. justinei, is mainly characterized by the absence of an anterior bulbous inflation of the oesophagus, body length of the gravid female (196 mm), conspicuously large amphids, number and distribution of cephalic papillae, and the morphology of larvae. It is the second known species of Philometra parasitizing fishes of the family Mullidae and the ninth species of this genus reported from marine fishes of the Mediterranean region. P. serranellicabrillae, studied for the first time by SEM, is redescribed.

Gongylonema neoplasticum was identified in the oesophagus of 14 wild rabbits (Oryctolagus cuniculus) from Portugal. This is the first record of Gongylonema neoplasticum in a naturally infected lagomorph species in Europe. This paper presents the most relevant measurements of adult worms and some of their surface features seen by scanning electron microscopy. Epidemiological aspects of G. neoplasticum such as geographical distribution, host spectrum and biological features are discussed.

Specimens of the fishes Rastrelliger kanagurta (Scombridae) and Siganus luridus (Siganidae) were caught in the Red Sea off the coast of Sharm El-Sheikh, South Sinai, Egypt. R. kanagurta was parasitised by Diplosentis nudus (Harada, 1938) Pichelin et Cribb, 2001 (Acanthocephala, Cavisomidae), and S. luridus by Sclerocollum rubrimaris Schmidt et Paperna, 1978 (Acanthocephala, Cavisomidae). The infection of R. kanagurta was followed monthly for one year (from September, 2004 to August, 2005). As a result, the seasonal cycle of D. nudus in its definitive host is described herein for the first time. The cycle is well-defined and extends for about 11 months (from October to August); in October, new generation of D. nudus starts to appear in the intestine of R. kanagurta; during the winter, the juvenile worms continued their growth; during the spring, most of the worms attained maturity and the mature worms copulated; during the summer, the worms began to die off naturally prior to their elimination from the intestine of the host. Sclerocollum rubrimaris is redescribed and Sclerocollum Schmidt et Paperna, 1978 is retained as a valid genus within the Cavisomidae.

European vipers are ambush predators with sporadic feeding events, thereby maintaining the digestive tract empty for long periods. According to previous studies relating lizards’ dietary habits and their helminth faunas, we predict poor gastrointestinal helminth communities in vipers. To test this hypothesis, we have examined the digestive tract of 86 specimens of Vipera aspis (L., 1758) and V. latastei Boscá, 1878, from several localities of the Iberian Peninsula. We found adults of only two nematode species Kalicephalus viperae (Rud., 1819) and Ophidascaris sp. and cysts adhering to the external wall on the stomach in case of two other nematode species Ascarops strongylina (Rud., 1819) and Spirurida gen. sp. All these nematodes are common parasite species in snakes, although Ophidascaris sp. has never before been recorded in Vipera sp. The low prevalence and small number of parasite species in Iberian vipers matched their low feeding rates. However, our results contrast with studies in Poland and Belarus of V. berus species, in which nematodes, as well as trematodes, are common and abundant. Rainfall rates are lower in the Iberian Peninsula than in eastern Central Europe, where amphibians are more available and consumed by V. berus. Amphibians, intermediate hosts for these helminths, have been recorded only sporadically as prey for V. aspis and V. latastei, thus supporting the absence of trematodes in both Iberian viper species. Among populations of Iberian vipers, the prevalence of parasites correlates with the feeding rate (i.e. percentage of vipers with prey), suggesting a linkage between the two parameters. In conclusion, our results suggest that several factors, including climatic characteristics of localities, feeding rates of predators, and type of prey consumed, influence the number and type of parasites in Iberian vipers.

Records of the European Harpirhynchidae Dubinin, 1957 (Acari, Prostigmata) are summarized and briefly discussed. This family is represented in Europe by 23 species belonging to three subfamilies, Harpirhynchinae (18 species recorded), Harpypalpinae Fain, 1972 (4 species recorded), and Ophioptinae Southcott, 1956 (1 species recorded). A new species Harpirhynchus dusbabeki sp. nov. from the bearded tit Panurus biarmicus (L., 1758) (Passeriformes, Timaliidae) in Slovakia is described. This new species differs morphologically from the two similar congeneric species, H. nidulans Nitzsch, 1818 and H. galeridae Fain, Bochkov et Mironov, 1999, by having setae 3a and two setae on both genua I and II.

The distribution of acetylcholinesterase (AChE) in oncospheres and developing cysticercoids of Hymenolepis diminuta was examined. The enzyme was localized in the nervous system and in some non-nerve cells of these larvae. In oncospheres AChE was detected in hook muscles and in the binucleated medullar center that is known to enclose two neurons. At early developmental stages of the cysticercoids the enzyme was localized in the post-oncospheral hook muscles and in subtegumental muscle fibers of the cercomer. At medium and late stages of development the activity of AChE was detected in the developing nervous system and in two and, subsequently, in four populations of cells, which gradually spread over the whole internal wall of the cyst, thus forming a thin multilayer AChE-positive lining of the cyst cavity. Following withdrawal of the scolex the lining separates the parenchyma of the turned neck from the cyst tissues and remains AChE-positive during the whole life of the parasite, i.e. up to the death of the infected host. The role played by non-neural AChE associated with the cyst cavity lining is unknown, but seems to regulate both the transport of nutrients and minerals into the scolex and waste substances in the opposite direction.

The accumulation of neutral lipids in the cells predetermined to evolve into the cyst cavity lining in Hymenolepis diminuta cysticercoids is presented. The differentiation of these cells from the mesenchyma cells and the accompanying systhesis of lipids began in very young, blastula-shaped larvae. Both the number of the cells and the amount of their lipids increased gradually during further development of the parasites. In the pre-encystment stage of the cysticercoids the cells concentrated around the cavity of the prospective cyst. Following encystment, the scolex and the inverted neck became surrounded by a compact mass of the cells, which started using the stored lipids as a source of energy indispensable for the formation of the cyst tissues and of the definitive multilayer lining of the cyst cavity. No neutral lipids were detected in the mature 23-day-old cysticercoids as well as in the experimentally excysted scoleces. Beside a low level of uniformly distributed phospholipids apparently associated with cell membranes, no local accumulations of these substances were observed at any step of the development of the larvae. The utilization of neutral lipids proves both the presence of a lipase-type enzyme(s) and an operative β-oxidation pathway in the cells of the cysticercoids, the latter feature being highly indicative of oxidative metabolism of these larvae.

Coccidiosis of chickens, caused by species of Eimeria (Protozoa, Apicomplexa), is an intestinal disease of major economic importance worldwide. In the present study, the reproductive characteristics of a precocious line (designated E. tenella Rt3+15) from Australia were investigated in chicken embryos and the implications of the findings briefly discussed.