Histopathological changes of micromamalian skin in feeding places of the ticks Ixodes trianguliceps, I. persulcatus and I. ricinus (Ixodoidea). P. 177-183.
Histopathological changes in the places of attachment and feeding of the Ixodes trianguliceps, I. persulcatus, and I. ricinus on natural hosts are similar. They pass through the stages of skin inflammation: perforation, exudation and proliferation. The mouthparts of tick contact with the host tissues. The fibrin deposit and callogen capsule surround the mouthparts. These species of ticks do not form the cement. Formation of the feeding cavity is caused by the salivation of ticks and neutrophil infiltration into surrounding tissues. Unnatural hosts (mice, rabbits) do not form the callogen capsule in the places of feeding, the callogen fibres are disposed irregular. Mast cells accumulate in the tick attachment site in the skin of natural host and degranulate in response to the tick salivary antigens releasing the histamine. Mediators involve cutaneous hypersensitivity reactions.
in RussianParasite-host associations of fleas and small mammals in the Omsk province. P. 184-191.
A generalized analysis of data on a flea fauna, range of their hosts in various natural zones, and features of parasite-host relationships between fleas and small mammals obtained in the Omsk province during long term researches in 1963—1997 is given. 35 flea species are recorded. The most mass species both on animals and in their nest is Ctenophthalmus assimilis; the numerous species are Amalareus penicilliger, Megabothros rectangulatus, M. walkeri, Peromyscopsylla silvatica, Ctenophthalmus unciatus, Palaropsylla sorecis, Doratopsilla birulai, Neopsylla pleskei, Hystrichopsylla talpae; the usual species — Ceratopsyllus garei, M. calcarifer, M. turbidus, Frontopsylla elata, Amphipsylla sibirica, A. kuznetzowi, Peromyscopsylla dasyenema, Radinopsylla integella, Catalagia dacenkoi. Other species are less numerous or infrequent. The general infection rate of the flea populations on rodents and insectivores makes 30.4%. For certain species it reaches 65.1% (on red-backed vole Cletrionomys rutilus), for regular groups — 86.9% (on shrews of the genus Sorex). The greatest variety of the flea populations is observed on Microtus arvalis, the least one — on Sorex caecutiens and S. daphaenodon. In the nests of small mammals the variety of fleas is significantly lower. Based on the index of flea species relative "loyalty" to small mammals and their nest we have recognized 6 groups of fleas.
in RussianInfluence of parasites on host adaptations to environmental factors: host-parasite system molluscs — trematode parthenites. P. 192-200.
This laboratory study examined the survival of extreme environmental conditions by the White Sea periwinkle Littorina saxatilis. Molluscs from localities with high and low prevalence of Microphallus piriformes, which is a representative of the "pygmaeus" group of digeneans (Microp-hallidae), were compared. These parasites have not a stage of free-living cercariae in their life cycle. Metacercariae mature inside the sporocysts parasitizing the molluscan host. No negative influence of infection was found on resistance of molluscs to prolonged desiccation and extremes of air and water temperature. On the contrary, significant lower mortality of high infected snails was observed in some experiments. Exposure to fresh water was the only treatment that caused more intensive mortality of high infected snails in comparison with low infected one. The results of the experiments were discussed taking into consideration the available data on mechanisms of molluscan resistance and features in the relationships of "pygmaeus" group sporocysts with the organism of molluscan host. It was emphasized that the wide spread opinion regarding the only negative influence of trematode infection on the resistance of infected molluscs should be revised.
in RussianParasites-invaders of the Volga river basin: history in invasion, perspectives of dispersion, possibilities of epizootic. P. 201-212.
The fauna of fish parasites in the Volga river increased by 15 species in last time. These parasites have invaded together with introduced hosts or dispersed after destruction of some physical and ecological barriers. The infusoria Ambiphrya ameuri, cestode Cestobothrium acheilognathi, trematodes Amurotrema dombrovskajae and Sanguinicola skrabini have been introduced together with their hosts. A creation of water reservoirs destroyed ecological barriers and created favorable conditions for the migration and dispersion of parasites. The cestodes Eubothrium rugosum, Proteocephalus longicollis, and nematode Cystidicola farionis migrated from the North, Aspidogaster limacoides migrated from the South. The leech Caspiobdella fadejevi, trematodes Rossicotrema donicus, Apophallus muehlingi, Niccola skrjabini, Plagioporus skrjabini migrated through the Volga-Don channel. Some invader have already finished their dispersion in the water reservoirs of Volga river, other parasites still continue this process. South border of the E. rugosum range is in the Kujbyshev water basin, the leech C. fadejevi is distributed in all water basins, trematodes R. donicus, A. muehlingi and P. skrjabini are found in the Volga delta, while N. skrjabini has already reached the Saratov water basin. Perspectives of new invaders and epizootic significance of invaders is discussed.
in RussianTo the history of fish parasite fauna formation in the water bodies of the European North. P. 213-220.
The fauna of fish parasites in water bodies of the Europaen North was formed in the Holocene by species immigrated from adjacent regions. The Volga River basin played a very important role in the history of the formation of fauna in water bodies of the European North (North Dvina and Onega river basins, Onega and Ladoga lakes), because there were wide connections between them in the postglacial period.
in RussianEight new species of Coccidia (Sporozoa, Coccidia) from fishes of the continental waters of Russia. P. 221-227.
Description of coccidian species infecting freshwater fishes is given. Localities: Neman river, Goussia peleci sp. n. — oocyst 37.5—45 x 35—42.5 µm, oocyst residuum (OR) absent, sporocysts 20—22.5 x 15—17.5 µm, Stieda body (SB) absent, sporocyst residuum (SR) present, host (h) — Pelecus cultratus; G. cultrati sp. n. — oocyst 22.5—30 µm, OR absent, sporocysts 12.5 x 15 µm, SR, SB absent, wall 2—2.5 µm, h — P. cultratus; G. arinae sp. n. — oocyst 12.5 x 17.5 µm, OR present, sporocysts 5—7.5µm, SR, SB absent, h — P. cultratus; G. vimbae sp. n. — oocyst 15—22.5 µm, OR absent, wall 2.5 µm, sporocysts 5—7.5 µm, SR, SB absent, h — Vimba vimba vimba; G. gymnocephali sp. n. — oocyst 25 x 25 µm, OR absent, sporocysts 10 x 12.5 µm, SR, SB absent, h — Gymnocephalus cernuus; G. cernui sp. n. — oocyst 15—22.5 µm, OR present, sporocysts 5—12.5 µm, SR, SB absent, h — Gym. cernuus; G. luciopercae sp. n. — oocyst 30—35х30 µm, OR absent, sporocysts 12.5—15 x 10—12.5 µm, SB absent, SR present, h — Stizostedion lucioperca; Eimeria fluviatili sp. n. — oocyst 20—22.5 µm, OR present, sporocysts 7.5 x 12.5 µm, SB present, SR absent, h — Perca fluviatilis.
in RussianMicrosporidians, knidosporidians and ciliatae (Peritricha: Peritrichida: Mobilina) found in fishes from water bodies of the Minusinsk depression. P. 228-234.
During the period of 20 years (1964—1984) 10000 fish specimens collected in water bodies of the Minusinsk depression have been examined by the methods of total and partial parasitological dissections. The studies were held in the Enisey, Abakan, Tasheba, and Tuba rivers, in the Krasnoyarskoye and Sayano-Shushenskoye reservoirs, and in some lakes. The data on a parasite species composition of microsporidians, cnidosporidians and ciliatae are given.
in RussianQuantitative indices of the infection with gregarinids (Sporozoa: Gregarinina) in the euphausiid Thysanoessa raschii (Crustacea: Euphausiacea). P. 235-240.
An occurrence of the gregarinids in the gastrointestinal tract of euphausiid Thysanoessa raschii was studied in summer 1982 and winter 1983 in the southern part of the Barents Sea. The infection rates of T. raschii with gregarinids was 0% in winter and 89.4% in summer. The highest level of infection was 1035 gregarinida per crustacean. The level of infection was found to be related mainly to be food composition (no gregarinids was found in euphausiids with copepods in stomach, the high level — in crustaceans with phytoplankton in the gastrointestinal tract).
in RussianSome problems of the taxonomy of monogeneans of the order Dactylogyridea (Platyhelminthes: Monogenea). P. 241-248.
Different taxonomic problems of the Dactylogyridea Bychowsky, 1937 are discussed. From the recent point of view, all old genera need a careful revision. Taxa of higher ranks should be analysed taking into account their host phylogeny and zoogeography. The order Tetraonchidea Bychovsky should be disband and all its families should be moved to the Dactylogyridea. The aberrant families Montchadskyellidae and Anoplodiscidae also belong to the Dactylogyridea. Dactylogyrideans are most similar to the primitive monogeneans.
in RussianInfluence of the cestode Bothriocephalus acheilognathi on morphological and physiological characteristics of carps reared in warm water. P. 249-256.
Influence of the cestode Bothriocephalus acheilognathi on morphological and physiological characteristics of carps and protein content in organs and tissues of fishes reared in basins with warm water have been studied. Dynamics of weight, length, height and index of nourishment state have been examined in carps noninfected and infected with cestodes.
in RussianEctoparasites of the gray rat Rattus norvegicus in some areas of steppe and forest-steppe zones of Ukraine. P. 257-261.
More than 2000 gray rat specimens and 5 burrows have been examined in several regions of steppe and forest-steppe zones of Ukraine. 24 647 representatives of Arthropoda of 39 taxonomic groups have been collected. Species composition of parasitic mites (Gamasida, Trombiculidae, Myobiidae, Listophoridae) and insects (Anoplura, Siphonaptera) has been defined.
in RussianChronicle. P. 262-264.
Summary is absent.
in Russian
Go top