Journal of the Faculty of Fisheries and Animal Husbandry, Hiroshima University Volume 9 Issue 2
1971-03-20 発行

Studies on the Uteri and Ovaries in Fur Seals : I. Macroscopical Observation with Special Reference to the Multiparaous Changes

オットセイ雌生殖器の研究 : I 経産にともなう変化の肉眼的観察
Okamoto, Toshikazu
Gross analyses of the ovaries and uterine horns from 29 female fur seals, collected in western Pacific Ocean, off northern Japan from January to May, were done to clarify the macroscopically visible changes of the ovaries and uterine horns in pregnancy and after parturition.
1. The corpora lutea of pregnancy, corpora albicantia and white scars in the ovaries were macroscopically distinguished.
2. The judgement of the parturition experience by the presence of corpora albicantia may not be always correct, because the corpora albicantia and the white scars seemed to disappear within four years after parturition and the corpora lutea of nonpregnancy exists.
3. The results of the present study on the appearance of corpora lutea and corpora albicantia supported the view that most female fur seals matured sexually at three or four years old.
4. From the relation between the number of the corpora albicantia and the structures of the uterine horn, it was presummed that the multiparous changes could be expressed by the macroscopically visible changes of the uterine horns of fur seals.