| Project/Area Number |
61560338
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
基礎獣医学
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| Research Institution | Gifu University |
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Principal Investigator |
TIBA Tosiro Faculty of Agriculture, Gifu University, Professor, 農学部・農授 (90001528)
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| Co-Investigator(Kenkyū-buntansha) |
KITA Isao Faculty of Agriculture, Gifu University, Associate Professor, 農学部, 助教授 (60021705)
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| Project Period (FY) |
1986 – 1988
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| Project Status |
Completed (Fiscal Year 1988)
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| Budget Amount *help |
¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 1988: ¥100,000 (Direct Cost: ¥100,000)
Fiscal Year 1987: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1986: ¥1,200,000 (Direct Cost: ¥1,200,000)
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| Keywords | Spermatogenesis / Spermatogonia / 季節繁殖動物 / 静子形成 / 精粗細胞 / 季節繁殖 / 精上皮 / 精巣 |
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| Research Abstract |
Seasonal changes in speramtogenesis and other related sexual functions in five species of seasonal breeders were investigated.
1. Japanese selow In a total of 568 animals, it was clarified that the testis size and androgen levels in testes as well as in serum showed a dicidede tendency to decrease from December to March. In young animals, the spermatogenic activity and testosterone levels attained the adult levels at the age of 2.5 to 3.
2. Ferrets and minks Enhanced proliferation of undifferentiated type of spermatogonia was observed after cell loss during the non-breeding season. This reaction of the spermatogonia is particularly sensitive to degeneration of differentiated type A spermatogonia.
3. Golden hamster In the animals exposed to short photoperiods, enhanced proliferation of isolated type of undifferentiated A spermatogonia (AIs) was demonstrated after degeneration of other developed germ cells. This reaction seemed to be particularly sensitive to loss of defferentiated type B spermatogonia. The results obtained from ferrets, minks and hamsters suggest the presence of feedback mechanism between differentiated and undifferentiated spermatogonia. This mechanism may play an important role for regulating annual changes in spermatogonial proliferation in seasonal breeders.
4. Japanese macaques The results were obtained from two animals that during the non-breeding season undifferentiated type Ad spermatogonia increased in number. This finding seems to be supprted by the observations mentioned above.
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