In vitro growth of oocytes from primordial follicles isolated from frozen–thawed lamb ovaries

Alginate encapsulation supports the growth and differentiation of human primordial follicles within ovarian cortical tissue

“…Although primordial follicle isolation and culture has been accomplished in species including the mouse and lamb, attempts to do the same in primates have been less successful [41][42][43]. Primordial follicles are difficult to isolate and culture because they are small, the connections between the granulosa cells and oocytes are minimal, and the ovarian environment surrounding them is comprised of dense extracellular matrix components [44,45].…”

Interaction between ascorbic acid and follicle-stimulating hormone maintains follicular viability after long-term in vitro culture of caprine preantral follicles

“…Thus, it is very important to develop a long-term in vitro culture system that allows follicles to grow to more advanced stages, with the added benefit of providing a better understanding of ovarian physiology. In fact, few studies have demonstrated that long-term in vitro culture of preantral follicles enclosed in ovarian tissue promotes follicular activation in sheep [4] and humans [5] and [6]. To our knowledge, this is the first report that demonstrates the maintenance of caprine preantral follicle survival using histological and ultrastructural analysis, even after longterm culture (14 d) in domestic animals.…”

“…Therefore, an extended culture period may be required for preantral follicle development. However, few long-term in vitro culture studies achieved follicular activation, namely, the transition from primordial to growing follicles in ovines [4] and humans [5] and [6].…”

In vitro development of primordial follicles after long-term culture of goat ovarian tissue

“…Therefore, an extended culture period may be required for a follicle to develop to the preovulatory stage. Few long-term in vitro culture studies have achieved follicular activation, i.e., the transition from primordial to primary follicles (ovine: Muruvi et al, 2005; human: Otala et al, 2002 andSadeu et al, 2006) or the development of antral follicles (bovine: Gutierrez et al, 2000;mouse: Mitchell et al, 2002). Recently, Gupta et al (2008) produced buffalo embryos after the long-term culture of isolated large secondary follicles.…”

“…Interestingly, in most of the in vitro culture systems, independent of the culture period, the medium has been totally or partially replaced by fresh medium every other day (Silva et al, 2004 andMuruvi et al, 2005).…”