this manuscript reviews the present knowledge related to folliculogenesis in sheep.folliculogenesis starts with formation of primordial follicles before birth, present as a pool containing a certain number of follicles. by the attainment of puberty, a group of follicles from that pool starts to grow, a process known as primordial follicle activation or recruitment. the number of growing primord...

background: nandrolone decanoate (nd) is an anabolic androgenic steroid (aas) which influences the ovarian structure and function. we assessed the effects of nd on the ovarian volume, number of primordial follicles, and level of hormones and also evaluated the modulatory effects of gonadotropins on the histopathological changes imposed by the administration of nd. methods: six groups of sprague...

The assembly of the developmentally arrested primordial follicle and the subsequent transition of the primordial follicle to the primary follicle are critical processes in normal ovarian physiology that remain to be elucidated. Ovarian follicles do not proliferate and the primordial follicles present in the neonate represent the total number of gametes available to a female throughout her repro...

Background: With all the recent advances in cancer treatments, many young cancer patients find themselves facing the prospect of losing their fertility after aggressive chemotherapy or radiotherapy. Cryopreservation of ovarian cortical tissue has emerged as a potential option to restore fertility in these young women. Materials and Methods: Because autotransplantation of cryopreserved ovarian c...

Factors that cause some primordial follicles to enter the growth phase while the others remain quiescent are unknown. The hypothesis was tested that primate primordial follicles can survive and initiate growth in vitro in serum-free medium. Superficial pieces of ovarian cortex, containing mostly primordial follicles, were obtained from baboon fetuses during late gestation and cultured for 0, 2,...

The mechanisms that regulate the gradual exit of ovarian follicles from the non-growing, primordial pool are very poorly understood. A better understanding of the signals that initiate follicular growth in mammals, and of the conditions necessary for sustained growth of early preantral follicles in vitro, could have practical implications for contraception, alleviation of infertility, and regul...

Initiation of folliculogenesis through the induction of primordial follicle development in the ovary has an important role in determining the fertility and reproductive fitness of most mammalian species. The factors that control this critical process are largely unknown. The hypothesis tested in the current study was that kit-ligand/stem cell factor (KL) promotes the initiation and progression ...

We hypothesized that the ovulatory response of one ovary to FSH would be related positively to the size of the primordial and growing pools of follicles in the other ovary. Nonlactating cows (n = 26) were unilaterally ovariectomized and 2 days later were superovulated. The superovulatory response was classified as Low (< 5 corpora lutea [CL]), Medium (5-14 CL), or High (> 14 CL). Surface follic...

In a sexually mature female, primordial follicles continuously leave the arrested pool and undergo the primordial to primary follicle transition. The oocytes increase in size and the surrounding squamous pre-granulosa cells become cuboidal and proliferate to form a layer of cuboidal cells around the growing oocyte. This development of the primordial follicle commits the follicle to undergo the ...

This manuscript reviews the present knowledge related to folliculogenesis in sheep.Folliculogenesis starts with formation of primordial follicles before birth, present as a pool containing a certain number of follicles. By the attainment of puberty, a group of follicles from that pool starts to grow, a process known as primordial follicle activation or recruitment. The number of growing primord...