Abstract
The ultrastructure of the ovary of Milnesium tardigradum during early vitellogenesis is described. Within the ovary, there were large multinuclear cells surrounded by many mononuclear oocytes. Observation of serial sections revealed four multinuclear cells that were connected to each other by cytoplasmic bridges. Each peripheral oocyte was connected to the multinuclear cell. An enormous ER-like structure was conspicuous in the centre of the multinuclear cell. The presence of large numbers of lipid droplets and yolk granules in both multinuclear cells and many mononuclear oocytes suggested a role as nurse cells. A small number of these oocytes grow to be eggs. The structural features of the multinuclear nurse cell were compared with other known examples.
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References
J. Amsellem C. Ricci (1982) ArticleTitleFine structure of the female genital apparatus of Philodina (Rotifera, Bdelloidea) Zoomorphology 100 89–105 Occurrence Handle10.1007/BF00310356
H. Baumann (1964) ArticleTitleÜber den Lebenslauf und die Lebensweise von Milnesium tardigradum Doyère (Tardigrada) Veröffentlichungen aus dem Überseemuseum Bremen, Reihe A 3 161–171
M. E. Bentfeld (1971) ArticleTitleStudies of oogenesis in the rotifer, Asplanchna. I. Fine structure of the female reproductive system Zeitschrift für Zellforschung 115 165–183 Occurrence Handle1:STN:280:DyaE3M7otlGmtg%3D%3D
J. Büning (1994) The Insect Ovary. Ultrastructure, Previtellogenic Growth and Evolution Chapman & Hall London
R. A. Dewel D. R. Nelson W. C. Dewel (1993) Tardigrada F. W. Harrison M. E. Rice (Eds) Microscopic Anatomy of Invertebrates, Vol. 12. Onychophora, Chilopoda, and Lesser Protostomata Wiley-Liss, Inc. New Yolk 143–183
R. C. King J. Büning (1985) The origin and functioning of insect oocytes and nurse cells G. A. Kerkut L. I. Gilbert (Eds) Comprehensive Insect Physiology Biochemistry and Pharmacology, Vol. 1. Embryogenesis and Reproduction Pergamon Press Oxford 37–82
T. Makioka (1988) ArticleTitleOvarian structure and oogenesis in chelicerates and other arthropods Proceedings of Arthropodan Embryological Society of Japan 23 1–11
E. Marcus (1928) Bärtierchen (Tardigrada) F. Dahl (Eds) Die Tierwelt Deutschlands NumberInSeriesVol. 12 Gustav Fischer Jena 1–230
M. Matsuzaki H. Ando (1977) ArticleTitleOvarian structures of the adult alderfly, Sialis mitsuhashii Okamoto (Megaloptera: Sialidae) International Journal of Insect Morphology & Embryology 6 17–29 Occurrence Handle10.1016/0020-7322(77)90027-7
L. Rebecchi R. Bertolani (1994) ArticleTitleMaturative pattern of ovary and testis in eutardigrades of freshwater and terrestrial habitats Invertebrate Reproduction and Development 26 107–118
A. C. Suzuki (2003) ArticleTitleLife history of Milnesium tardigradum Doyère (Tardigrada) under a rearing environment Zoological Science 20 49–57 Occurrence Handle12560601
M. G. Walzl (1992) ArticleTitleUltrastructure of the reproductive system of the house dust mites Dermatophagoides farinae and D. pteronyssinus (Acari, Pyroglyphidae) with remarks on spermatogenesis and oogenesis Experimental & Applied Acarology 16 85–116 Occurrence Handle10.1007/BF01201494 Occurrence Handle1:STN:280:DyaK3s7lsVWqtA%3D%3D
B. Weglarska (1979) ArticleTitleElectron microscope study on previtellogenesis and vitellogenesis in Macrobiotus richtersi J. Murr. (Eutardigrada) Zeszyty Naukowe Uniwersytetu Jagielloniskiego, Prace Zoologiczne 25 169–189
B. Weglarska (1987) ArticleTitleYolk formation in Isohypsibius (Eutardigrada) Zoomorphology 107 287–292 Occurrence Handle10.1007/BF00312174
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Suzuki, A.C. Ovarian Structure in Milnesium tardigradum (Tardigrada, Milnesiidae) during Early Vitellogenesis. Hydrobiologia 558, 61–66 (2006). https://doi.org/10.1007/s10750-005-1416-6
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DOI: https://doi.org/10.1007/s10750-005-1416-6