Q112443673
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Spermiogenesis and ultrastructure of mature spermatozoon of the caryophyllidean cestode Hunterella nodulosa, a parasite of suckers (Catostomidae), have been studied by transmission electron microscopy. This monozoic tapeworm is unique in its mode of attachment and represents the second North American species studied. The process of spermiogenesis of H. nodulosa follows the general pattern already described in other caryophyllideans. The most characteristic feature is the presence of a slight rotation of the flagellar bud, which seems to be a typical character of spermiogenesis in this cestode group. The mature spermatozoon of H. nodulosa is characterized by the presence of one axoneme of 9 + "1" type of the trepaxonematan flatworms surrounded by a semi-arc of cortical microtubules in its anterior extremity, parallel nucleus and cortical microtubules arranged in a parallel pattern, which corresponds to the Type III pattern of cestode spermatozoa according to Levron et al. (2010). Comparison of the present data with those available for other caryophyllideans did not reveal substantial differences, even though they belong to different families, infect different hosts (catostomid, cyprinid and siluriform fishes) and occur in distant zoogeographical regions. This indicates uniformity of the process of sperm formation and spermatozoon ultrastructure in one of the evolutionarily most ancient groups of tapeworms.
- MeSH
- Cestoda fyziologie ultrastruktura MeSH
- máloostní MeSH
- nemoci ryb epidemiologie parazitologie MeSH
- spermatogeneze fyziologie MeSH
- spermie cytologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
- Geografické názvy
- Severní Amerika MeSH
Examination of some freshwater and brackishwater (estuarine) fishes in South Carolina in October 2009 yielded, in addition to other parasites, 2 little-known nematode species identified as Dichelyne fastigatus Chandler, 1935 (Cucullanidae), from the red drum, Sciaenops ocellatus (Linnaeus), from an estuary, and Rhabdochona ovifilamenta Weller, 1938 (Rhabdochonidae), from the shorthead redhorse, Moxostoma macrolepidotum (Lesueur), from Lake Moultrie. Light and scanning electron microscopy (the latter used for the first time for these species) made it possible to describe several important, but previously unreported, taxonomic features in D. fastigatus, such as the location of the excretory pore and deirids, the shape of deirids and a gubernaculum, the shape and size of eggs, the presence of precloacal ventral oblique muscle bands, and 11 pairs of caudal papillae and a pair of phasmids. It distinctly differs from the most similar Dichelyne cotylophora (Ward and Magath, 1917), a parasite of North American freshwater percids, in the number and arrangement of postanal papillae and by a markedly elevated cloacal region. Records of Dichelyne lintoni Barreto, 1922, from S. ocellatus probably concern D. fastigatus. Examination of R. ovifilamenta revealed a high degree of morphologic and biometric variability in this species. Based on our analysis, Rhabdochona laurentiana Lyster, 1940 , Rhabdochona milleri Choquette, 1951, and Rhabdochona catostomi Kayton, Kritsky, and Tobias, 1979, are synonymized with R. ovifilamenta Weller, 1938, typically a parasite of North American catostomids.
- MeSH
- Ascaridida anatomie a histologie klasifikace MeSH
- infekce hlísticemi podtřídy Secernentea epidemiologie parazitologie veterinární MeSH
- infekce hlísticemi řádu Ascaridida epidemiologie parazitologie veterinární MeSH
- infekce hlísticemi řádu Spirurida epidemiologie parazitologie veterinární MeSH
- máloostní parazitologie MeSH
- mořská voda MeSH
- nemoci ryb epidemiologie parazitologie MeSH
- Perciformes parazitologie MeSH
- prevalence MeSH
- sladká voda MeSH
- Spiruroidea anatomie a histologie klasifikace MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Jižní Karolína MeSH
The vitellogenesis of the trematode Aspidogaster limacoides (Aspidogastrea: Aspidogastridae), a parasite of cyprinid fishes, is described here using transmission electron microscopy. Four different stages of vitellocytes are differentiated: immature vitellocytes, early maturing vitellocytes, advanced maturing vitellocytes and mature vitellocytes. The process follows the same general pattern already described in other free-living neoophorans and parasitic flatworms (i.e. Trematoda, Monogenea and Cestoda): differentiation into mature vitelline cells involves the development of mitochondria, granular endoplasmic reticulum, Golgi complexes, lipid droplets and shell-globules. Mature vitellocytes of A. limacoides are composed of numerous shell-globule clusters, few lipid droplets and glycogen granules. They differ from those of another aspidogastrean Rugogaster hydrolagi in that they possess numerous globules tightly packed and by the presence of only one type of vitelline material. The interstitial tissue of vitelline follicles of A. limacoides contains a peripheral nucleus and long cytoplasmic projections extending between vitelline cells. Since aspidogastreans are considered as an archaic group of parasitic flatworms and thus have a strategic phylogenetic position, future works needs to pay special attention to the ultrastructural and chemical composition of mature vitellocytes within this basal group of trematodes.
- MeSH
- Cyprinidae parazitologie MeSH
- infekce červy třídy Trematoda parazitologie veterinární MeSH
- nemoci ryb parazitologie MeSH
- ovum fyziologie ultrastruktura MeSH
- transmisní elektronová mikroskopie MeSH
- Trematoda klasifikace růst a vývoj metabolismus ultrastruktura MeSH
- vitelogeneze fyziologie MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Using transmission electron microscopy, spermiogenesis and the spermatozoon ultrastructure are described in Aspidogaster limacoides (Aspidogastrea, Aspidogastridae), from two cyprinid fishes, Abramis sapa and Blicca bjoerkna, from eastern Slovakia and north-western Russia. Results of the present investigation permit, for the first time in Aspidogastrea, to describe general pattern of spermiogenesis and the organization of the spermatozoon in this presumably the most basal group of parasitic flatworms (Neodermata). Spermiogenesis starts by the formation of a zone of differentiation characterized by long striated rootlets, two centrioles giving rise to flagella, and intercentriolar body composed of different electron-dense plates. Later, a flagellar rotation followed by a proximodistal fusion of the flagella with the cytoplasmic extension takes place. Beside the possession of elements typical of Neodermata, such as two axonemes of the 9 + '1' trepaxonematan pattern, nucleus, mitochondrion and cortical microtubules, the mature spermatozoon of A. limacoides exhibits characteristics unique in Aspidogastrea: (a) a long undulating membrane, (b) an electron-dense zone, and (c) a lamellate body. The terminology and structure of different typical elements of Aspidogastrea are discussed. It is interesting to note that the long undulating membrane and a continuous row of cortical microtubules have already been described in polyopisthocotylean monogeneans, which can be a case of convergence unless future phylogenetic studies confirm relatedness of these groups.
- MeSH
- buněčné jádro ultrastruktura MeSH
- Cyprinidae parazitologie MeSH
- organely ultrastruktura MeSH
- spermatogeneze MeSH
- spermie ultrastruktura MeSH
- transmisní elektronová mikroskopie MeSH
- Trematoda fyziologie izolace a purifikace ultrastruktura MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
- Geografické názvy
- Rusko MeSH
- Slovenská republika MeSH
The scolex surface of the mature spathebothriidean Cyathocephalus truncatus (Pallas, 1781), a parasite of the brown trout Salmo trutta fario L., was studied using scanning and transmission electron microscopy. A particular attention was paid to microtriches, unique structure on the surface of the Cestoda. The scolex of C. truncatus is covered with two types of filiform microtriches (filitriches): aciculate (approximately 3 microm long) and capillate (approximately 10 microm long). Capillate microtriches, which have never been reported in any other spathebothriideans, are described for the first time using transmission electron microscopy. The tegument covered with filiform microtriches only (no spiniform microtriches are present) is typical of cestode groups supposed to be the most basal, e.g., Gyrocotylidea, Spathebothriidea, and Caryophyllidea.
