Exposure of different cryoprotectants and concentrations on diameter and number of the granulosa cells of bovine preantral follicles

Abstract

This study evaluated the effect of glycerol (GLY), dimethyl sulfoxide (DMSO) and propylene glycol (PROH) in diameter of follicle, of oocyte and of granulosa cells number of preantral follicles cattle. Ovarian fragments were exposed to cryoprotectants at concentrations of 20 and 40% for 10 min. Then, the tissue was fixed in Carnoy and processed by traditional technique of histology. Slides were stained by hematoxylin and eosin and evaluated under optical microscope equipped with eyes wide with morphometric. Data were analyzed by ANOVA and Tukey test. Regarding diameter of the follicle, no difference was found among the control and the groups exposed to the cryoprotectants. However, in relation to the diameter of the oocyte, 40% concentration in all tested cryoprotectants the primary follicles showed reduction in diameter, including 20% of propylene glycol. For primary follicles, only 40% of glycerol presented difference from control group. For the granulosa cells 40% of DMSO and 20 and 40% of PROH showed significant reduction compared to control group, in primary follicles. In conclusion primary follicles were resistant to cryoprotectants effects. For the primary structures, glycerol, dimethyl sulfoxide and propylene glycol led to reduction of diameter of oocyte and number of granulosa cells but not of follicular diameter.