Populational variability of Proteocephalus longicollis (Cestoda: Proteocephalidae) in the vendace Coregonus albula from lakes of Karelia. P. 3-12.
Populational variability of Proteocephalus longicollis from the vendace inhabiting various types of Karelian water bodies was studied. High phenotypic diversity of the helminth and polymorphism in the cestode's major functional complexes — attachment, trophic and reproduction — are established. High degree of phenotype pool realization was determined for various P. longicollis populations. Traits belonging to different functional complexes were shown to have different variability patterns. The highest stability was shown for the attachment organs of P. longicollis, which had similar values of qualitative indices and nature of variation. The traits of the trophic and reproduction complexes are more variable. The conclusion was made that the high intrapopulation diversity of P. longicollis is a response to high ecological variability of the vendace, and the distinctions in the phenotype variability of the helminth reflect the differences between population development patterns of the parasite (cestode P. longicollis) and its host (vendace Coregonus albula) in lakes of Karelia.
in RussianModification of the structure of penial glands in males of the intertidal molluscs Littorina saxatilis and L. obtusata under the influence of the infestation by trematode parthenites. P. 13-22.
Sporocycts of the "pygmaeus" microphallides (Microphallus piriformes) are localized in hepatopancreas and gonads of Littorina molluscs causing total parasitic castration. A histological study of penial glands in Littorina saxatilis and L. obtusata males infested with trematodes M. piriformes has been made. Copulatory organs of noninfested molluscs, molluscs after recent contamination (with not completely formed daughter sporocysts), and molluscs containing mature metacercariae inside daughter sporocysts were examined. Based on the data obtained, probable dynamics of the histological structure of infested glandular apparatus was established. It was shown, that the trematode infestation have an influence on the muscular and secretory parts of penial glands. The wall of the penial gland muscular capsule becomes more fine in infested L. saxatilis. On the contrary, this wall is vastly thicker in infested L. obtusata, as compared with noninfested individuals. Glandular cells of the molluscs' penial glands decreases the amount of granular secret in both species. In L. obtusata the number of secretory cells is shown to be reduced up to their total disappearance. The above pathological changes probably prevent normal function of penial glands.
in RussianDynamics of physiological parameters in the nestlings of black-backed gull Larus marinus experimentally infested by the cestode Microsomacanthus ductilus (Cestoda: Hymenolepididae). P. 23-30.
The effect of the invasion with the cestode Microsomacanthus ductilus on physiological and biochemical processes in black-backed gull Larus marinus was examined. Experimental invasion of the gull nestling by the cestodes has been performed. Dynamics of the protein, lipid, and carbohydrate metabolism in the time history of the invasion was observed, in comparison with noninfested nestling. Increasing of the content of α-globulins and decreasing of the content of protein and albumin in the blood plasma of experimentally infested birds were registered to 4th day after invasion. To 7th day after invasion the level of general lipids and phospholipids decreases, while the content of γ-globulins and modified form of albumin increases. To 10th day after invasion symptoms of intoxication were observed, but some parameters proved to be reverted to normal condition. So, it can be assumed, that the most intensive reorganization of the metabolism in infested birds takes place in the period between 4th and 7th days after infestation. Possible causes of the observed phenomena are discussed.
in RussianThe role of marine amphipods in the life cycles of the cestode genus Microsomacanthus at Bering Sea coast of Chukchi Peninsula. First results of the investigation. P. 31-40.
Investigation of the helminth fauna was carried out in different amphipode species at Bering Sea coast of Chukchi Peninsula in July—September 2004. More than 3700 amphipode specimens of the following three species were examined: Lagunogammarus setosus Dementieva, 1931 (n = 2772 specimens) (Gammaridae), Eogammarus barbatus Tzvetkova, 1965 (n = 471), and Spinulogammarus subcarinatus (Bate, 1862) (n = 509) (Anisogammaridae). Numerous metacestodes of four hymenolepidid species from the genus Microsomacanthus Lopez-Neyra, 1945 were found, namely gull parasites M. ductilis (Linton, 1927) and M. lari (Yamaguti, 1940) comb. n., and eider parasites M. minimus Ryjikov, 1965 and M. somateriae Ryjikov, 1965. Relative selectivity of cestodes in the choice of intermediate host is revealed: M. ductilis and M. somateriae are found on L. setosus only, while M. minimus and M. lari are found in both species of anisogammarids. Brief descriptions and figures of metacestodes are given; data on extensiveness and intensity of the intermediate hosts invasion in six collection localities are provided. The greatest extensiveness of invasion is recorded in L. setosus (E. I. in M. ductilis was 1.98%, in M. somateriae — 1.84%). The identification of metacestodes is confirmed by the finding of mature cestodes of all above species in two Pacific eider specimens (Somateria mollissima var. nigrum) and three gull specimens (one Larus argentatus and two L. hyperboreus) captured in the area where the largest sample of Gammaridae was collected.
in RussianParthenogenetic generations of Helicometra fasciata Rud., 1819 (Trematoda: Opecoelidae) in the Black Sea molluscs Gibbula adriatica. P. 41-52.
Morphology of the Helicometra fasciata Rud., 1819 parthenogenetic generation from the Black Sea gastropods Gibbula adriatica (Phil.) was studied for the first time. Data on seasonal dynamics of the hemipopulation of daughter sporocysts are given. Daughter sporo-cysts of H. fasciata infest 10 ± 0.2% of G. adriatica (mainly specimens of larger size and elder age classes). As a rule, local microhemipopulations of daughter sporocysts castrate mollusc hosts.
Reproduction of H. fasciata daughter sporocysts is asynchronous: daughter sporocysts born specimens of next sporocyst generation during autumn and winter, and then they begin producing cercaria. In winter development of the cercaria embryo is blocked. Second change of the character of the each sporocyst' posterity is impossible because of the annual life cycle of G. adriatica. Endogenous agglomeration of the H. fasciata daughter sporocysts is extremely little: individuals of next sporocyst generation develop from no more than 2% of embryonic balls. Energy resources of the mollusc host are used by the H. fasciata daughter sporocysts mainly for producing cercaria; this fact can be interpreted as an adaptation of H. fasciata to using medium-sized, short-living mollusc hosts.
in RussianCharacteristics of the seasonal development of Schistogonimus rarus (Trematoda: Prosthogonimidae). An essay on quantitative estimation of the trematode in the ecosystem of the Malye Chany lake (south of Western Siberia). P. 53-65.
Quantitative estimation of the trematode Schistogonimus rarus at the stage of cercaria is carried out in the ecosystem of the Malye Chany lake, south of Western Siberia, on the base of long-term data obtained in 1995—2002. Average daily emission of the S. rarus cercaria was shown to be significantly higher in larger mollusc hosts (p < 0.01), by the results of laboratory investigations. Moreover, significant decrease of the average daily emission of the S. rarus cercaria from June to July is established (p < 0.01). It was revealed, that emission of the S. rarus cercaria in the south of Western Siberia (both in natural and laboratory conditions) lasts no more than 50 days and is finished in August. The infestation rate of the mollusc host Bithynia troschelii by the S. rarus parthenites varied from 0.28 to 1.44% in different years and correlated with the water temperature at first ten days of June (r = 0.75). Flow of the S. rarus cercaria (specimens per square meter) was estimated on the base of the quantitative characteristics of the cercaria emission, data on the infestation rate of the host population, and data on the host abundance. The flow of the cercaria varied from 6000 (in 1998) up to 330000 (in 2000) per season and correlated with the water temperature in third ten days of June (r = 0.71).
in RussianNosogeographical estimation of the territory of Primorsky Krai based on the analysis of spatial and temporal structure of the incidence of infectious diseases. P. 66-74.
Nosogeographic estimation of the territory of Primorsky Krai has been carried out on the base of the long-term data on spatial distribution of the incidence of infectious diseases. Analysis of the complex maps of the zoning allow us to say, that the territory of the region is rather clearly differentiated by the groups of infections.
in RussianInstructions to authors. P. 75-80.
Summary is absent.
in Russian
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