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Spatial colonization by feral domestic cats Felis catus of former wildcat Felis silvestris silvestris home ranges

100%

Sarmento P. , Cruz J. , Eira C. , Fonseca C.

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nr 1

31-38

EN

Presently, wildcatFelis silvestris silvestris Schreber, 1777 populations are fragmented and rapidly declining in most of Europe. Although habitat destruction possibly constitutes the most serious threat to wildcat survival, hybridisation with feral domestic cats is also a critical problem. However, the mechanisms that allow domestic cats to colonise former wild cat home ranges are yet unclear. The present paper describes the decrease of typical phenotypic wildcats and the increase of phenotypic domestic cats in a remote wild area of Portugal (Serra da Malcata). A field survey using box-traps and radio-tracking between 1998 and 2001 revealed that wildcats were widespread in the study area and no domestic cats were present. A second survey using camera traps between 2005 and 2007 revealed only one wildcat whereas four typical domestic phenotype individuals were photographed. The present study clearly emphasizes the need for urgent measures aimed at preserving wildcat populations. These measures should include a national census of the species and an extensive monitoring of genetic integrity of wildcat populations, followed by the elaboration of a wildcat conservation action plan.

2

The system Tetrabothrius bassani (Tetrabothriidae)- Morus bassanus (Sulidae) as a bioindicator of marine heavy metal pollution

88%

Mendes P. , Eira C. , Vingada J. , Miquel J. , Torres J.

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nr 1

EN

Helminths are known to accumulate higher amounts of certain elements than their hosts. The present study assesses the accumulation of heavy metals in Tetrabothrius bassani and in its host, the Atlantic gannet (Morus bassanus) found dead due to bycatch along the seashore in the centre of Portugal. Samples of kidney, liver and pectoral muscle of 23 infected gannets, as well as specimens of T. bassani were analysed for As, Cd, Cr, Cu, Hg, Mn, Pb, Se and Zn by ICP-MS. The evidenced lower concentrations of Cr and Pb in tissues of gannets in comparison to an earlier study performed in the same area may reveal a change in the diet of M. bassanus between both study periods. The highest bioaccumulation factor was obtained for Cd with a 12.7-times higher concentration in the cestode than in gannet muscle. Lead concentration in T. bassani was 6.9-times higher than in kidney tissue, 8.5-times higher than in muscle and 9.5-times higher than in liver of M. bassanus. The cestode/seabird system T. bassani/M. bassanus can be considered a promising bioindicator system to monitor environmental Cd and Pb pollution in marine ecosystems.

3

Ultrastructure of the tegument of the anoplocephalid cestode Mosgovoyia ctenoides [Railliet, 1890] Beveridge, 1978

88%

Mlocicki D. , Eira C. , Zebrowska J. , Miquel J. , Swiderski Z.

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nr 3

4

Post-embryonic development and ultrastructural characteristics of the polycephalic larva of Taenia parva Baer, 1926 [Cyclophyllidea, Taeniidae]

75%

Swiderski Z. , Miquel J. , Mlocicki D. , Georgiev B. B. , Eira C. , Grytner-Ziecina B. , Feliu C.

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tom 52

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nr 1

EN

Post-embryonic development and fully-formed polycephalic larvae of Taenia parva Baer, 1926 were examined by light (LM) and transmission electron microscopy (TEM). Three developmental stages were recognised: (1) an early stage of exogenous budding at the surface of the central vesicle; (2) a stage of polycephalic cyst development accompanied by segmentation of the growing larval strobile and an obvious decrease in the size of the central vesicle; (3) fully-formed larval strobile and invaginated scoleces. In fully-developed encysted polycephalic larvae, there are usually 14–24 segmented larval strobilae, each terminating with an invaginated scolex; larval strobilae arise from a common central vesicle and remain attached posterior to it during the entire development. The number of segments varies between 109 and 120 per larval strobila. The polycephalic larvae examined closely resemble the strobilocercus type of taeniid larvae. The structure of developing and fully-formed larvae was examined by TEM. The tegument, scolex, subtegumental musculature of the strobilar segments, protonephridial system, calcareous corpuscles and medullary parenchyma of larvae exhibit general similarity with the same structures in adults at both LM and TEM levels. The morphogenesis of the larva of T. parva is compared with that of the polycephalic larvae of other Taenia spp. (T. krepkogorski, T. twitchelli and T. endothoracica) and with other asexually-multiplying cestode larvae (mesocestoidids, hymenolepidids and dilepidids).

5

Ultrastructure of oncospheral hook formation in the cestode Mosgovoyia ctenoides [Railliet, 1890] Beveridge, 1978 [Cyclophyllidea, Anoplocephalidae]

75%

Mlocicki D. , Swiderski Z. , Conn D. B. , Eira C. , Miquel J. , Baranowska-Korczyc A.

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tom 50

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nr 2

EN

The ultrastructure of oncospheral hook formation in the anoplocephalid cestode Mosgovoyia ctenoides (Railliet, 1890) Beveridge, 1978, is described. The hook morphogenesis takes place inside the six symmetrically arranged hook-forming cells, the oncoblasts. They show characteristic large nuclei of semilunar shape, localized at one pole of the embryo. At the beginning of the hook formation, the "hook-forming centre" appears in the cytoplasmic part of each oncoblast. It consists of numerous free ribosomes and polyribosomes surrounded by several mitochondria and Golgi complexes. The hook-forming centre is involved in synthesis of an electron-dense, undifferentiated hook primordium, which undergoes progressive differentiation and elongation into the fully developed hook. A fully formed oncospheral hook consists of the three parts: blade, shank, and base. Each hook, at the site of its protrusion from the oncosphere, is surrounded by two electron-dense rings interconnected by a circular septate junction. The hook material consists of two or three layers that differ in electron density: (1) a moderately electron-dense core, (2) a middle layer of low electron density, and (3) a highly osmiophilic cortex. Wide bands of hook muscles are attached to the basal and collar parts of the hook. The hook blades project outside of the oncospheral body into a large cavity delimited by the hook region membrane attached at this pole directly to the oncospheral surface. In the fully developed oncosphere of M. ctenoides, the three pairs of oncospheral hooks and their muscles form a complex "hook muscle system", responsible for coordinated hook action. The differentiation and ultrastructure of oncospheral hooks in the oncospheres of M. ctenoides are compared to those described in other cestode species.