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1.
We document histological changes through ontogeny in the epiphyseal cartilage of the third phalanx of Rana caralitana from Turkey and provide an assessment of the maturation of the epiphysis from newly metamorphosed froglets to 10‐year‐old individuals. The epiphysis of R. caralitana is compared to other Rana taxa previously studied, and we report on novel histological data pertaining to later stages of epiphyseal growth in this taxon. In addition, we document the development of endochondral ossification in late stages of ontogeny in R. caralitana. Our results suggest a correlation between the long lifespan of R. caralitana and the developmental changes and maturation of the epiphyseal cartilage in this taxon. This study also provides a quantitative assessment of the different regions of the epiphyseal cartilage in the epiphysis of Rana through ontogeny, and has therefore permitted quantifiable deductions about the relative maturation and differentiation of the chondrocytes of the epiphysis through time. Anat Rec, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

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Pelophylax caralitanus is a medium‐sized frog that is endemic to the upland Lake District of south‐central Turkey and currently identified as a threatened species as a result of overharvesting and habitat modification. In this report, demographic data are provided for four major lakeside populations of this species based on a skeletochronological analysis of bone growth in large samples of frogs that were captured and released during 2011 and 2013. Adult males (aged 2–9 years) and females (aged 2–10 years) ranged in size from 66 to 105 mm snout‐vent length (SVL) and 65 to 110 mm SVL, respectively, and typically attained sexual maturity in their second (low‐elevation sites) or third (high‐elevation sites) summer of growth following metamorphosis. The four populations exhibited differences in growth rate and age at sexual maturity, which appeared to reflect differences in the average monthly temperature and length of the growth season rather than elevation per se, that is, warmer temperatures and longer growth seasons resulted in smaller adults. All populations had a similar overall age structure, with approximately equal frequencies of individuals in the five age and size classes following maturity. Anat Rec, 301:1224–1234, 2018. © 2017 Wiley Periodicals, Inc.  相似文献   

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Gnathostomatid nematodes identified morphologically as Spiroxys japonica Morishita, 1926 were collected from the dark-spotted frog Pelophylax nigromaculatus (Hallowell) (Amphibia: Ranidae) in China. Light and scanning electron microscopy were used to study the morphology of this species in detail. Previously unreported morphological features are revealed and others corrected. In addition, adult nematodes of S. japonica collected from P. nigromaculatus and Spiroxys hanzaki Hasegawa, Miyata & Doi, 1998 collected from Andrias japonicus (Temminck) (Caudata: Cryptobranchidae) in China and Japan, respectively, and the third-stage larva of S. japonica collected from Lithobates catesbeianus (Shaw) (Anura: Ranidae) in Japan, were characterised using molecular methods by sequencing and analysing ribosomal [large ribosomal DNA (18S) and internal transcribed space] and mitochondrial [cytochrome c oxidase subunit 1] target regions, respectively. The new morphological and genetic data contributes to a more accurate diagnosis of this hitherto little known nematode genus.  相似文献   

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Millán  Javier 《Parasitology research》2018,117(9):3015-3018
Parasitology Research - Information about the role of micromammals in the epidemiology of Leishmania infantum and Babesia sp. in southern Europe is scarce. Wild micromammals were captured in...  相似文献   

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This paper presents the first record of two native Mediterranean cymothoid species caught attached to introduced Lessepsian rabbitfishes. This is also the first record of cymothoids from the coastal waters of Libya. Anilocra physodes was collected from Siganus luridus while Nerocila bivittata was found on both Siganus rivulatus and S. luridus. Rabbitfishes in the southern central Mediterranean have acquired native Mediterranean cymothoids but do not seem to be infested along the Levantine coast.  相似文献   

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We genetically analysed malaria parasites (Protozoa) in three Mediterranean blue tit (Cyanistes caeruleus) populations from central Spain. A total of 853 breeding individuals were screened for parasites of the genera Plasmodium and Haemoproteus using a very efficient polymerase chain reaction approach that amplifies a partial segment of the mitochondrial cytochrome b gene of these parasites. We have found six lineages of Plasmodium (SGS1, GRW11, COLL1, DELURB4, GRW04 and BLUTI10) parasitizing the studied populations but we did not detect any infection by Haemoproteus. One of the detected lineages (BLUTI10) has not been previously described in any bird species and this is the first study recording lineages DELURB4 and GRW04 in blue tits. SGS1 (belonging to the morphospecies Plasmodium relictum) was the most frequent lineage (overall prevalence, 24?%), whereas the other lineages showed a much lower prevalence (<4?%). Only a small proportion (12.2?%) of positive amplifications of the most common lineage (SGS1) was detected in blood smears using light microscopy and infection intensities were very low (mean?±?SE, 2.0?±?1.4 parasites/2,000 erythrocytes). We have also found strong inter-population variability in prevalence patterns (12–41?% for lineage SGS1), suggesting important differences in parasite transmission rates among the geographically close studied localities.  相似文献   

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Four relatively uncommon members of the family Priapulidae (Priapulida) from very different parts of the world were examined to determine the presence of a parasitic coccidian in their midgut. The parasite was found in three of those priapulid species, Priapulopsis bicaudatus, P. australis, and Halicryptus higginsi, but not in the fourth one, Priapulus tuberculatospinosus. Using electron-microscopy techniques, we compared parasites of the different species with one another and with a parasite of Priapulus caudatus investigated by McLean in 1984. All of these parasites apparently belong to the same species and are likely to be Alveocystis intestinalis, a coccidian first described by Beltenev from P. caudatus and H. spinulosus. The present work greatly expands the geographical range of Alveocystis intestinalis and documents an uncommon case of low host specificity in eimeriid coccidians. Received: 5 August 1996 / Accepted: 28 August 1996  相似文献   

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Species that are introduced to novel environments can lose their native pathogens and parasites during the process of introduction. The escape from the negative effects associated with these natural enemies is commonly employed as an explanation for the success and expansion of invasive species, which is termed the enemy release hypothesis (ERH). In this study, nested PCR techniques and microscopy were used to determine the prevalence and intensity (respectively) of Plasmodium spp. and Haemoproteus spp. in introduced house sparrows and native urban birds of central Brazil. Generalized linear mixed models were fitted by Laplace approximation considering a binomial error distribution and logit link function. Location and species were considered as random effects and species categorization (native or non-indigenous) as fixed effects. We found that native birds from Brazil presented significantly higher parasite prevalence in accordance with the ERH. We also compared our data with the literature, and found that house sparrows native to Europe exhibited significantly higher parasite prevalence than introduced house sparrows from Brazil, which also supports the ERH. Therefore, it is possible that house sparrows from Brazil might have experienced a parasitic release during the process of introduction, which might also be related to a demographic release (e.g. release from the negative effects of parasites on host population dynamics).  相似文献   

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A new diagnostic strategy was assessed for the routine diagnosis of intestinal parasites in returning travellers and immigrants. Over a period of 13 months, unpreserved stool samples, patient characteristics and clinical data were collected from those attending a travel clinic. Stool samples were analysed on a daily basis by microscopic examination and antigen detection (i.e. care as usual), and compared with a weekly performed multiplex real-time polymerase chain reaction (PCR) analysis on Entamoeba histolytica, Giardia lamblia, Cryptosporidium and Strongyloides stercoralis. Microscopy and antigen assays of 2,591 stool samples showed E. histolytica, G. lamblia, Cryptosporidium and S. stercoralis in 0.3, 4.7, 0.5 and 0.1% of the cases, respectively. These detection rates were increased using real-time PCR to 0.5, 6.0, 1.3 and 0.8%, respectively. The prevalence of ten additional pathogenic parasite species identified with microscopy was, at most, 0.5%. A pre-selective decision tree based on travel history or gastro-intestinal complaints could not be made. With increased detection rates at a lower workload and the potential to extend with additional parasite targets combined with fully automated DNA isolation, molecular high-throughput screening could eventually replace microscopy to a large extent.  相似文献   

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Summary It has been assumed until recently that frogs were hyperopic as observed by retinoscopy, which is the universal method of objective refraction. However this method is believed to be erroneous because light is reflected by a layer other than that of the receptors. Using a refractometer in which light is focused in the eye and viewed ophthalmoscopically, the eyes of the frog are found to be emmetropic. It is assumed that these data are valid because of the underlying principle of this instrument, and because this result is in agreement with recent electrophysiological measurements.  相似文献   

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The neuropeptide FF (NPFF) is a member of the RFamide related peptides (FaRPs) that share the dipeptide Arg-Phe-NH2 at their C-terminal. It was originally isolated from bovine brain and its wide distribution has been demonstrated in the brain of several mammalian species. By means of an NPFF antiserum we have investigated the distribution pattern of NPFF-like immunoreactive cells and fibers in the brain of anuran and urodele amphibians. In both amphibian orders, the most conspicuous labeled cell population was found in the preoptic area and hypothalamus, primarily in the suprachiasmatic region. Numerous fibers reached the median eminence and the intermediate lobe of the hypophysis. Only in the anuran brain cells were observed in the pallium and septum. In the urodele, cells and fibers of the terminal nerve were distinctly labeled. Cell bodies were widely distributed in the reticular formation of anurans and, in both orders, a large cell population was found in the nucleus of the solitary tract and the spinal cord. Comparable fiber distribution between both orders exists in which the basal telencephalon (mainly the amygdaloid complex), the hypothalamus and the spinal cord are the regions most richly innervated. The distribution pattern of NPFF-like immunorective elements in the brain of amphibians, which only partly overlaps with those of other FaRPs, supports the notion that a NPFF-like peptide exists in amphibians. On the basis of its localization, this peptide may act as a hypophysiotropic neurohormone and be involved in background adaptation. Its wide distribution in similar zones of the brain in amphibians and mammals suggests that functional roles of this peptide have been conserved in vertebrate evolution.  相似文献   

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The increasing movement of people to wilderness areas, shrinking of wildlife habitats and the resulting urbanisation of wildlife has led to growing concerns about the transfer of parasitic diseases, particularly from contaminated faeces. Faecal samples from wild carnivores in Ireland were examined for the presence of protozoan and nematode parasites. Red fox (Vulpes vulpes) samples (n?=?91) were positive for Uncinaria stenocephala (38 %), Eucoleus aerophilus (26 %), Toxocara canis (20 %), Trichuris vulpis (4 %) and Isospora-like oocysts (9 %). Badger (Meles meles) samples (n?=?50) were positive for Uncinaria criniformis (40 %), E. aerophilus (6 %) and Isospora-like oocysts (16 %). No parasites were observed in pine marten (n?=?48; Martes martes) faeces. Approximately 5 % of American mink (Mustela vison) samples were positive for Cryptosporidium by polymerase chain reaction (identified as Cryptosporidium andersoni (n?=?3) and ‘mink’ genotype (n?=?1)). The results suggest that wild carnivores in Ireland have a range of parasites, although it is unclear from the present study to what extent these infections are associated with morbidity. While it can be expected that, via their faeces, wild carnivores contribute to the spread of these parasites, they are unlikely the primary source of environmental contamination. Therefore, they should not always be the principal target of control measures.  相似文献   

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Summary Myelinated dendrites — probably of motoneurons — were found in the spinal cord of the frog. It is assumed that the myelin sheath, by increasing the membrane resistance, improves the function of the dendrite as a cable.Supported by the Deutsche Forschungsgemeinschaft  相似文献   

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