Morphological characteristics of the ovary, uterus and embryo during the delayed implantation period in the Hokkaido brown bear (Ursus arctos yesoensis)

@article{Tsubota1993MorphologicalCO,
  title={Morphological characteristics of the ovary, uterus and embryo during the delayed implantation period in the Hokkaido brown bear (Ursus arctos yesoensis)},
  author={Toshio Tsubota and Hiroshi Kanagawa},
  journal={Journal of Reproduction and Development},
  year={1993},
  volume={39},
  pages={325-331}
}
Ovaries having corpora lutea and uteri of 6 female Hokkaido brown bears (Ursus arctos yesoensis), which were legally killed by hunters from October to December in Hokkaido, Japan, were examined macroscopically and histologically. Four of the 6 female bears had unimplanted embryos in the uterine lumen during the period of delayed implantation between October 19 and November 20. Ovaries of bears which had unimplanted embryos contained the corpora lutea with extensive vacuolation or numerous… 

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