Electron microscope studies of spermateleosis in Fasciola hepatica L

Gresson, R. A. R.; Perry, Margaret M.

doi:10.1016/0014-4827(61)90079-9

Cited by 39 publications

(14 citation statements)

References 13 publications

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“…+/À presence/absence of considered character (Justine 1991(Justine , 1995. Nuclear elongation and migration at least into the proximal median process is a universal phenomenon in the Digenea (Gresson and Perry 1961;Sato et al 1967;Rees 1979). The single noteworthy characteristic concerns the sequence in the migration process of nucleus and mitochondria along the spermatid body.…”

Section: Discussionmentioning

confidence: 99%

Dicrocoelium hospes Looss, 1907 (Digenea, Dicrocoeliidae): spermiogenesis, mature spermatozoon and ultrastructural comparative study

et al. 2005

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This work describes the first ultrastructural results on spermiogenesis and on the mature spermatozoon of Dicrocoelium hospes (Trematoda, Digenea) collected in Bos indicus from Senegal (Africa). Examination of this species was processed by TEM. Spermiogenesis follows the general pattern found in the digenean, but reveals a particularity consisting of the appearance of glycogen granules in the late spermatids within the testes. The mature spermatozoon possesses five distinct regions and presents all features found in Digenea gametes: two axonemes, mitochondria, nucleus and parallel cortical microtubules. However, several characters allow us to distinguish D. hospes from other digenetic trematodes within the Dicrocoeliidae family. In fact, we observed several structures that are absent in the other species of Dicrocoeliidae studied until now, such as: a cytoplasmic expansion, extramembranar ornamentation, spine-like bodies and two parallel mitochondria in the mature sperm. Moreover, additional particular characteristics were observed in this species in both extremities of the spermatozoon. This work produced new data on the ultrastructure of this trematode family which may be useful for phylogenetic purposes.

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Section: Discussionmentioning

confidence: 99%

Dicrocoelium hospes Looss, 1907 (Digenea, Dicrocoeliidae): spermiogenesis, mature spermatozoon and ultrastructural comparative study

et al. 2005

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“…The authors considered these structures as an evidence for belonging to the gonial stem line. In trematode adults, the nuage-like structures, referred to as "nucleoluslike cytoplasmic bodies," were recorded in oocytes of Fasciola hepatica (Gresson 1964), Gorgoderina attenuata (Koulish 1965), Pharyngostomoides procyonis (Grant et al 1977), and Prosthodendrium ascidia (Podvyaznaya 1990). In this connection, it is interesting to note the obvious similarity in the fine organization of the germinal masses described in the present study and the young ovaries observed by Orido (1987) in developing lung flukes Paragonimus ohirai.…”

Section: Discussionmentioning

confidence: 99%

An ultrastructural study of reproduction in the sporocysts of Prosorhynchoides gracilescens (Digenea: Bucephalidae)

Podvyaznaya

2007

Parasitol Res

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The germinal development in Prosorhynchoides gracilescens sporocysts was studied using electron microscopy. The germinal cells proliferated and developed within multiple floating germinal masses located in the terminal portions of sporocyst branches. The germinal masses were composed of supporting and germinal cells. Supporting cells possessed numerous flattened extensions that spread around and between developing germinal cells to form three-dimensional mesh network, which maintained the integrity of the germinal mass. Morphological evidences of close interactions between supporting and germinal cells were numerous gap junctions between the two cell types and phagocytosis of small fragments of germinal cells cytoplasm by supporting cells. The germinal cells displayed structural differences that seemed to reflect their sequential developmental changes. These changes included (1) cell growth and increase of organelles number, (2) dispersion of nuclear chromatin and increase of nucleolus size, (3) polarization of the cell, (4) appearance of specific structures such as nuage and laminated inclusions. The germinal cells left the germinal masses to finish their differentiation in the body cavity and then cleaved to give rise to cercarial embryos. Ultrastructural features of the germinal elements of P. gracilescens sporocysts are discussed in the light of existing controversy concerning the nature of the germinal sacs reproduction.

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“…Numerous studies have been carried out on the spermatogenesis of flukes, for example, Gresson [3] explains the basics of the phenomenon, and there are also many other studies on the spermatogenesis of the genus Fasciola [1,2,[4][5][6][7]29]. These researches were based on observations of the spermatogenesis process and the results agree in most of the points, although differ in some aspects.…”

Section: Discussionmentioning

confidence: 99%

Abnormal Spermatogenesis in the Common Liver Fluke (Fasciola sp.) from Japan and Korea.

1998

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ABSTRACT. Diploid and triploid specimens of Japanese and Korean Fasciola sp. showed abnormality in their spermatogenesis. Live germ cells obtained from the testes were observed under a differential interference contrast microscope. In the stages from spermatogonium to spermatid, the cells combined together at the central cytoplasmic bridge during a series of divisions. One spermatogonium becomes a cell group of 8 primary spermatocytes through 3 mitoses. Until the primary spermatocyte stage, cells are divided in a uniform manner. In most of the diploid specimens, the primary spermatocytes are irregularly divided into non-uniform secondary spermatocytes, however, some specimens perform a regular division. In the majority of triploid flukes, the primary spermatocytes are divided in a regular pattern, but some of the specimens perform an irregular division. The non-uniform spermatids do not perform a spermiogenesis. In the diploid specimens, no spermatozoa were found that were produced by spermiogenesis. Whereas in the triploid specimens, some spermatids distributed uniformly on the surface went through a spermiogenesis. We observed some moving spermatozoa in one triploid specimen. The spermatozoa possibly retain their normal reproductive function. -KEY WORDS: chromosome, Fasciola, parthenogenesis, spermatogenesis, triploid.

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Electron microscope studies of spermateleosis in Fasciola hepatica L

Cited by 39 publications

References 13 publications

Dicrocoelium hospes Looss, 1907 (Digenea, Dicrocoeliidae): spermiogenesis, mature spermatozoon and ultrastructural comparative study

Dicrocoelium hospes Looss, 1907 (Digenea, Dicrocoeliidae): spermiogenesis, mature spermatozoon and ultrastructural comparative study

An ultrastructural study of reproduction in the sporocysts of Prosorhynchoides gracilescens (Digenea: Bucephalidae)

Abnormal Spermatogenesis in the Common Liver Fluke (Fasciola sp.) from Japan and Korea.

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