Fujita Health University
Fujita Health University
Fujita Health University
Research Institute of Environmental Medicine, Nagoya University
Research Institute of Environmental Medicine, Nagoya University
Research Institute of Environmental Medicine, Nagoya University
Aichi University of Education
Johannes Gutenberg University, Mainz
出版者
宇宙開発事業団
出版者（英）
National Space Development Agency of Japan (NASDA)
In a space experiment, the adaptation of goldfish behavior during flight and readaptation after landing were investigated. Six goldfish (one normal, one with otoliths removed on both sides, four with otoliths removed on one side) were flown in a Fish Package (F/P) of Aquatic Animal Experiment Unit (AAEU). The Dorsal Light Responses (DLRs) of fish with otoliths removed were recorded after operation until launch and after landing. The behavior of the fish in microgravity were recorded with a video camera on Mission Elapsed Time (MET) Day-00, 02, 05, 08, 12. On MET Day-00, the two fish with otoliths removed on one side showed flexion of the body toward the operated side. These fish also showed rolling behavior toward the operated side. However, the body flexion disappeared on MET Day-05 or MET Day-08. No rolling behaviors were observed after that time, which might indicate adaptation in microgravity. The normal fish and the fish with otolith removed on both sides showed backward looping responses during the 13 days mission. Although the frequency of looping episodes decreased after MET Day-08, five fish still showed looping response at MET Day-12, that was the last day of video recording on orbit. In microgravity, visual system of fish did not seem to provide sufficient cues to prevent them from looping and rolling. After landing, no looping and no rolling behavior were observed. However, the tilt angle of the DLR increased in the fish with otolith removed five month before launch but not in normal and those with otoliths removed two weeks before launch. These results suggest that the behavioral dysfunction and the adaptational process in space are dependent on vestibular inputs.
微小重力下における魚の前庭順応機構の研究(GOLDFISH)
00271001.pdf
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