Studies on the estrus cycle of the ground squirrel (Citellus citellus L.) at experimentally induced hibernation.
Eighty-five ground squirrels (C. citellus L.) were examined immediately after arousal (March-June). It was established that the animals were in estrus at the end of March; in April they were pregnant; in May they were in lactation; and in June they were already at rest, a postlactation period. Fifteen ground squirrels were treated with Hibernal and then placed in a chamber for 30 days at external temperature, 8-12 degrees C. In this case the estrus cycle of hypothermic ground squirrels was not changed. A retarded involution of corpus luteum persisted for a month and cystic follicles appeared in the ovary.
Tsvetkov
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T
Central Problem Laboratory for Cryobiology and Freeze-Drying, Sofia, Bulgaria.
Takeva
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D000818:Animals; D003338:Corpus Luteum / Q000502:physiology; D004971:Estrus / Q000502:physiology*; D005260:Female; D007036:Hypothermia, Induced; D007774:Lactation / Q000502:physiology; D010053:Ovary / Q000033:anatomy & histology / Q000502:physiology; D011247:Pregnancy; D012589:Sciuridae / Q000502:physiology*