Differential Counts of Glycogen-free and Glycogen-laden Ova in Rat Ovaries during Estrous Cycle, Pregnancy and Lactation

Abstract

The results obtained in this investigation are summarized as follows:1. The glycogen-free ova in the secondary and GRAAFian follicles at the stages of pregnancy and lactation increased as compared with those at the estrous cycle stage, whereas glycogen-laden ones decreased at those stages, and at the stage of estrous cycle after weaning both the glycogen-free and glycogen-laden ova reached the same level as those at the estrous cycle stage. The percentage of the glycogen-free ovaw as higher at the stages of pregnancy and lactation than at the stages of estrous cycle and that after weaning, whereas that of the glycogen-laden ova was lower at the former two stages.2. The glycogen-free atretic ova in the secondary and GRAAFian follicles increased at the pregnancy stage as compared with those at the estrous cycle one. The glycogen-laden ova decreased at the lactation stage. At the stage of estrous cycle after weaning, both the glycogen-free and glycogen-laden ova reached the same level as those at the estrous cycle stage. The percentage of the glycogen-free atretic ova was higher at the stages of pregnancy and lactation than at the stages of estrous cycle and of estrous cycle after weaning, whereas that of the glycogen-laden ova was lower at the stages of pregnancy and lactation, nearly coinciding with the results about the normal ova in the secondary and GRAAFian follicles.3. The corpora lutea at the stages of pregnancy and lactation decreased as compared with those at the stage of estrous cycle, and then at the stage of estrous cycle after weaning, the corpora lutea reached the same level as those at the stage of estrous cycle.