Follicular dynamics in sheep and cattle

Modulation of the effects of FSH, androstenedione, epidermal growth factor (EGF) and insulin-like growth factor I (IGF-I) on bovine granulosa cells by GCIF, a growth-inhibitory factor of low molecular mass from bovine follicular fluid

“…Oestrogens in turn increase granulosa cell proliferation (Driancourt, 1991 DiZerega, 1989). EGF is one of the most potent stimulators of granulosa cell proliferation (May et al, 1988).…”

“…These growth factors are among the most potent stimulators of granulosa cell growth in vitro (Gospodarowicz and Bialecki, 1979). In vivo granulosa cells are known to have receptors for both EGF (Brigstock et al, 1989) and IGF-I (Kotsuji et al, 1990), although the precise role of these growth factors in vivo is, as yet, not fully understood (Driancourt, 1991). The Hynes et al (1996) reported the partial purification of a granulosa cell inhibitory factor (GCIF) of low molecular mass from bovine follicular fluid that inhibited granulosa cell pro¬ liferation in vitro.…”

The potential for gamete recovery from non-domestic canids and felids

“…When performing its gametogenic function, the follicle is an essential element for maintenance of oocyte viability, seeking to assure growth and maturation of immature oocyte and, finally, to release a mature oocyte by the ovulation process (Figueiredo et al, 2002). It is known that the ovarian follicular population seems to be made up of thousands of follicles in different mammalian females (Driancourt, 1991). Thus, oocyte retrieval represents a rich source of genetic material to be used as a foundation for genetic banks, aiding in endangered species preservation, mainly in relation to the possibility of collecting material originated from post mortem or convalescent animals.…”

From the germinal cells to the newborn animal: The transmission of genes and life through the generations

“…The first one, the 'basal' growth concerns follicles, from the primordial stage till the preantral stage (Hage et al, 1978;Driancourt, 1991;Driancourt et al, 1991). This phase is mainly under paracrine control of growth factors (GF) (Peters et al, 1973).…”