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1

Helminth parasites in native and invasive mammal populations: comparative study on the Barbary ground squirrel Atlantoxerus getulus L. [Rodentia, Sciuridae] in Morocco and the Canary Islands

100%

Lopez-Darias M. , Ribas A. , Feliu C.

Acta Parasitologica

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2008

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tom 53

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nr 3

EN

A total of 51 and 21 adults of Barbary ground squirrels (Atlantoxerus getulus) were trapped during May–July 2006 from the introduced populations on Fuerteventura Island (Canary Islands) and the native populations in Morocco, respectively. One trematode, 1 cestode and 4 nematode species were recovered belonging to five families: Brachylaima sp. (Brachylaimidae), Catenotaenia chabaudi (Catenotaeniidae), Protospirura muricola (Spiruridae), Dermatoxys getula and Syphacia pallaryi (Oxyuuridae), and Trichostrongylus sp. (Trichostrongylidae). We report for the first time the presence of P. muricola, Trichostrongylus sp. and Brachylaima sp. in A. getulus. Brachylaima sp. was found in the insular population only, as a result of a diet that includes snails. The two oxyurids were found at both sites. The continental population showed higher species richness (5 vs 3 species). This is the first report of helminth parasites from A. getulus from the Canary Islands.

2

Ultrastructure of spermatogenesis of Taenia taeniaeformis [Batsch, 1786] [Cestoda, Cyclophyllidea, Taeniidae] and comparison of spermatological characters in the family Taeniidae Ludwig, 1886

88%

Miquel J. , Swiderski Z. , Foronda P. , Torres J. , Feliu C.

Acta Parasitologica

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2009

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tom 54

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nr 3

230-243

EN

The ultrastructure of spermatogenesis of Taenia taeniaeformis is described for the first time by means of transmission electron microscopy (TEM). Mature testes contain all stages of spermatogenesis; primary spermatogonia are usually situated at the periphery and mature spermatozoa in the centre of testes. The general process is similar to that described in other cestodes. Six incomplete, synchronic cytokineses occur: four mitotic and two meiotic cell divisions. All these divisions occur simultaneously, resulting in a rosette cluster of four tertiary spermatogonia, then eight quaternary spermatogonia, and subsequently sixteen primary spermatocytes. All of these enter into a growth period and their enlarged nuclei move to the periphery of cells of the rosettes. The first meiotic division forms thirty-two secondary spermatocytes and after the second meiotic division, there are sixty-four spermatids. Spermiogenesis in T. taeniaeformis corresponds to the Ba and Marchand’s Type 3 and begins with the formation of a differentiation zone in the form of a conical projection of cytoplasm delimited by a ring of arching membranes and surrounded by submembranous cortical microtubules. Within this area, there are two centrioles, orthogonally disposed, and vestigial striated rootlets. Only one of the centrioles develops a flagellum that grows externally to the cytoplasmic extension. Posteriorly, a flagellar rotation inferior to 90° occurs and the flagellum becomes parallel to the cytoplasmic extension. Later, the two processes fuse during the so-called proximodistal fusion. The nucleus elongates and moves into the cytoplasmic extension. In the final stage of spermiogenesis, a single crested body appears at the base of the differentiating spermatozoon. Finally, the ring of arching membranes constricts and the young spermatozoon detaches from the residual cytoplasm. Ultrastructural aspects of spermatogenesis are compared with that of other cestodes studied to date, particularly of the family Taeniidae.

3

Cadmium and lead concentrations in Moniliformis moniliformis (Acanthocephala) and Rodentolepis microstoma (Cestoda), and in their definitive hosts, Rattus rattus and Mus domesticus in El Hierro (Canary Archipelago, Spain)

88%

Torres J. , Eira C. , Miquel J. , Foronda P. , Feliu C.

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2011

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tom 56

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nr 3

EN

Information on parasites of vertebrates living in terrestrial ecosystems as monitoring tools for heavy metal environmental pollution is scarce. The present study evaluates the potential suitability of the models Rattus rattus/Moniliformis moniliformis and Mus domesticus/Rodentolepis microstoma as promising bioindicator systems for cadmium and lead pollutions under natural conditions. The highest level of cadmium was found in one specimen of M. moniliformis (335.2 ng g−1 wet weight) and the average concentration of Cd in the acanthocephalan was significantly higher than values found in R. rattus liver and kidney tissues. The maximum concentration of lead occurred in one specimen of R. microstoma (567.4 ng g−1 wet weight) and the average concentration of Pb in the cestode was significantly higher than values found in M. domesticus liver, kidney and muscle tissues. The present results allow proposing both models as promising biomonitoring systems to evaluate environmental cadmium pollution (mainly R. rattus/M. moniliformis) and lead contamination (especially M. domesticus/R. microstoma) in terrestrial nonurban habitats.

4

A transmission electron microscopical study of the tegument of Maritrema feliui (Digenea: Microphallidae)

88%

Swiderski Z. , Montoliu I. , Feliu C. , Gibson D. I. , Miquel J.

Acta Parasitologica

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2013

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tom 58

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nr 4

EN

The tegument of the microphallid digenean Maritrema feliui, examined by means of TEM, is described as a syncytial epithelium organised into two layers. The outer layer is an external anucleate, cytoplasmic region connected to a second region composed of nucleate perikarya (cytons) deeply embedded in the surrounding cortical parenchyma. The surface layer of the tegument is covered by a plasma membrane with many deep invaginations, which are apparently pinocytotic. This layer also bears numerous large, electron-dense spines of two types, which are intracellular and attached to the basal plasma membrane. Its cytoplasm is rich in free ribosomes, contains numerous mitochondria, disc-shaped granules frequently arranged in a rouleau, and several large, moderately electron-dense, membranous bodies. The subtegumentary perikarya and their nuclei, which are both flattened, are described in detail, as are their connections with the surface tegument. These perikarya appear to be the source of the disc-shaped granules and some of the other inclusions present in the surface layer. The main characteristics of the tegumental structure of M. feliui are commented upon in relation to the findings of previous publications and their suggested functions.

5

Spermiogenesis and sperm ultrastructure of Scaphiostomum palaearcticum Mas-Coma, Esteban et Valero, 1986 [Trematoda, Digenea, Brachylaimidae]

88%

Ndiaye P. I. , Miquel J. , Ba C. T. , Feliu C. , Marchand B.

Acta Parasitologica

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2002

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tom 47

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nr 4

EN

Spermiogenesis in Scaphiostomum palaearcticum begins with the formation of a zone of differentiation, which comprises striated rootlets associated with the two centrioles and an intercentriolar body in-between. It is characterised by an asynchronic flagellar rotation and subsequent proximo-distal fusion with a median cytoplasmic process. The migration of the nucleus toward the median cytoplasmic process before its fusion with the free flagella is also described. However, in the case of S. palaearcticum, the mitochondrion migrates toward the median cytoplasmic process before the fusion of the second axoneme. Attachment zones are also formed before the fusion of the axonemes with the median cytoplasmic process. The mature spermatozoon of S. palaearcticum is filiform and tapered at both ends and presents all the features found in the Digenea gamete: two axonemes, mitochondrion, nucleus and two bundles of parallel cortical microtubules. Nevertheless, certain features allow us to distinguish S. palaearcticum from other digenetic trematodes.

6

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.

Acta Parasitologica

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2007

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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).

7

Analysis of helminth communities of the pine marten, Martes martes, in Spain: Mainland and insular data

75%

Segovia J. M. , Torres J. , Miquel J. , Sospedra E. , Guerrero R. , Feliu C.

Acta Parasitologica

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2007

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tom 52

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nr 2

EN

The present study analyses the helminth communities found in one hundred and two specimens of Martes martes from the Iberian Peninsula and the Balearic Archipelago. The component community is constituted by seventeen helminth species, which frequency and mean abundance show a bimodal pattern. The set of core species is constituted by the trichurids Pearsonema plica, Eucoleus aerophilus and Aonchotheca putorii (72.2% of total helminth individuals found), while the remaining can be considered satellite species. Significant co-occurrences were found among E. aerophilus/A. putorii and E. aerophilus/P. plica. These results demonstrate the great importance of earthworms within the diet of pine marten and contribute to the knowledge of the pine marten’s food ethology, since this kind of prey normally goes undetected in diet studies. Several helminth species, as Sobolevingylus petrowi, Centrorhynchus aluconis, Uncinaria criniformis, Mastophorus muris and Spirura rytipleurites seurati seem to show geographical distributions limited to insular ecosystems. Moreover, helminth communities of M. martes among four Spanish territories, including mainland and insular areas, are characterized and compared.

8

Parasite fauna of rodents (Murinae) from El Hierro (Canary Islands, Spain): a multidisciplinary approach

51%

Feliu C. , Lopez M. , Gomez M. S. , Torres J. , Sanchez , Miquel J. , Abreu-Acosta N. , Segovia J. M. , Martin-Alonso A. , Montoliu I. , Villa M. , Fernandez-Alvarez A. , Bakhoum A. J. S. , Valladares B. , Oros J. , Foronda P.

Acta Parasitologica

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2012

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tom 57

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nr 2

EN

The parasite fauna (protozoa, helminths and insects) of the two most widespread Murinae rodents in El Hierro (Canary Islands, Spain), the black rat (Rattus rattus) and the house mouse (Mus musculus domesticus) was studied. Faunistic, ecological, ecotoxicological data, as well as information on the biology of some nematode parasites of R. rattus are provided. The present work is unprecedented in the Canary Islands, and provides the first data on the parasite biodiversity in Murinae from the archipelago. Concerning to parasitofaunas stands out: a) impoverishment of biodiversity of helminths respect of which have the same hosts in other islands; b) increasing the number of species of Siphonaptera, even compared with flea species that parasitize the same hosts from continental biotopes.