Piepenbreier, Klaus: Die Wirkung der Mikrogravitation auf das Abwehrsystemvon Schwertträgerfischen (Xiphophorus helleri, Heckel)in einem geschlossenen, aquatischen Ökosystem : immunologische und hämatologische Untersuchungen. - Bonn, 2006. - Dissertation, Rheinische Friedrich-Wilhelms-Universität Bonn.
Online-Ausgabe in bonndoc: https://nbn-resolving.org/urn:nbn:de:hbz:5N-08150
@phdthesis{handle:20.500.11811/2379,
urn: https://nbn-resolving.org/urn:nbn:de:hbz:5N-08150,
author = {{Klaus Piepenbreier}},
title = {Die Wirkung der Mikrogravitation auf das Abwehrsystemvon Schwertträgerfischen (Xiphophorus helleri, Heckel)in einem geschlossenen, aquatischen Ökosystem : immunologische und hämatologische Untersuchungen},
school = {Rheinische Friedrich-Wilhelms-Universität Bonn},
year = 2006,
note = {Background: The effect of space flight conditions on the immune system of humans and rodents was investigated since the beginning of space flight. Until now there were no investigations of the influence of microgravity on haematological parameters and defence functions in fish. The objective of this work was to investigate the influence of microgravity on the defence system of teleosts.
Methods: Aboard the 9 and 16 days lasting STS-89 and STS-90 space shuttle missions were four female swordtail fish (Xiphophorus helleri, Heckel 1848) each. During the space flights the Closed Equilibrated Biological Aquatic System (C.E.B.A.S.) was the habitat of the fish. Parallel to the space flights ground control experiments were performed. In addition fish from four terrestrial C.E.B.A.S. test runs and 39 female X. helleri that were kept under optimal conditions in aquaria were examined. In all tested fish the differential haemogram of nephritic tissue, the spontaneous cell proliferation activity of nephritic tissue and the phagocytosis activity of nephritic phagocytes were determined.
Results: A comparison of the examined defence system parameters of X. helleri from the C.E.B.A.S. space flight and from ground control experiments did not show statistically significant differences. However fish of some terrestrial C.E.B.A.S. experiments showed significant differences compared to the aquarium controls. They showed a decrease of the percentage of monocytes and lymphocytes in the differential haemograms as well as a reduction of phagocytosis and spontaneous cell proliferation activity. The decrease of monocytes and lymphocytes and the inhibition of phagocytosis are typical stress symptoms of teleosts. In addition it frequently came to significant differences between the data of swordtails from terrestrial C.E.B.A.S. experiments with different duration. Since the C.E.B.A.S. was a self-sustaining ecosystem environmental conditions developed during some C.E.B.A.S. experiments in a way that they were critical for the swordtails. Thus in addition to microgravity other environmental factors had an influence on the defence system of X. helleri.
Conclusion: On the basis of the available results it was not possible to show an influence of microgravity on the examined defence system parameters. Due to the significant differences between the data of fish from terrestrial C.E.B.A.S. experiments and the aquarium controls it is probable that, regardless of microgravity, the environmental conditions in the C.E.B.A.S. module had an influence on the examined defence parameters. Hence swordtails of terrestrial C.E.B.A.S. experiments showed symptoms that teleosts develop under the influence of stress. The frequent occurrence of significant differences between data of swordtails from terrestrial C.E.B.A.S. experiments with different durations indicates a correlation between the duration of exposure of X. helleri to critical environmental conditions and the state of their defence system. The results show that realistic assessments of the influence of microgravity on the defence system of swordtail fish will be possible when optimal environmental conditions for swordtail fish can be maintained during space flights.},

url = {http://hdl.handle.net/20.500.11811/2379}
}

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