Prenatal and Neonatal Exposure to Glyphosate-Based Herbicide Reduces The Primordial to Primary Follicle Transition in The Newborn Rat Ovary: A Preliminary Study

This study investigated how a glyphosate-based herbicide (GBH) affects the proportional distribution of ovarian follicles that develop from the 18 th day of the embryo period (E18) to the 7 th postnatal day (PND7) in newborn female rats. A total of 6 pregnant rats that were used in the study were divided into two groups so that there would be 3 pregnant rats in the control group and 3 pregnant rats in the GBH group. Starting from E21 to E18 the pregnant rats in the experimental group were administered at 50 mg/kg/day GBH subcutaneously (s.c.) and the physiological saline was administered as vehicle to the control group. Subsequently, female pups received vehicle or 2 mg/kg GBH from PND1 to PND7. On PND8, all female offspring (neonatal period, 6 newborn female rats from each group) were sacrificed by light ether anesthesia. For the histological examination of the dissected ovaries, the primordial, primary, secondary and preantral follicle numbers were determined using Crossman's modified triple staining method and Periodic Acid-Shiff (PAS) staining methods. The percentage of primordial follicles was significantly higher in the ovaries of female rats in GBH exposed group compare to the control group. However, the percentage of primary, secondary and preantral follicles was lower. Thus, it was observed that prenatal and neonatal GBH exposure decreased the transition of primordial follicle to primary follicle.