Bioscientifica Proceedings

The development of technologies to grow and mature oocytes from the most abundant primordial follicles holds many attractions for clinical practice, animal production technology and research. However, despite much research attention, it has proved difficult to grow follicles from early stages to maturity in vitro, as relatively little is known about the biology of oogenesis. It is clear that throughout oocyte development in vivo, follicle cell support is fund...

In ruminants, more than 30% of the embryonic losses observed after artificial insemination (AI) have an early origin, coincident with a marked elongation of the trophoblast which occurs before implantation. Several observations provide clear evidence that early elongation of the conceptus relies on cell multiplication, cell growth and cell shape remodeling. Recent results indicating an intense multiplication of a non-fully differentiated trophoblast, which still expresses ...

Summary. Embryo-maternal communication, as well as recognition and establishment of pregnancy, is predominantly controlled by secretion of hormones and proteins. Furthermore, uterine fluid serves as a histotroph and contains factors essential for embryo development and elongation, making it a meaningful source for proteomic approaches of early embryonic development. The studies included in this review address the analysis of uterine fluid and endometrium durin...

Abstract. The purpose of this review is to illustrate the critical value of integration of both in vitro and whole animal approaches in order to make real progress in terms of understanding the underlying mechanisms controlling ovarian follicle development and also in utilising domestic ruminants as models for the human in the translational development of interventions to address infertility. In terms of mechanistic aspects, this review concentrates o...

Abstract unavailable© 1987 Journals of Reproduction & Fertility Ltd...

During embryonic diapause, the development of the embryo is paused shortly after conception by metabolic or seasonal factors. When conditions become favorable, the embryo will resume development after reactivation by the maternal reproductive system. Inducing this resting state in in vivo or in vitro manipulated embryos may offer invaluable advantages in the long-term storage of embryos, therefore offering a potential worthwhile and novel alternative in assisted reproduction c...

Currently, there is no method to diagnose pregnancy non-invasively in most wildlife species that experience delayed implantation and pseudopregnancy, either during embryonic diapause or placental pregnancy. The aim of this study was to utilize farm-raised mink (Neovison vison) as a model species to evaluate changes in the fecal proteome associated with pregnancy. Specific objectives were to: 1) determine if fecal peptides were differentially abundant in parturient ver...

In experimentally induced diapause model in mice, blastocysts remain dormant for an extended period but resume implantation competency upon estrogen injection. The underlying mechanism by which extended longevity of dormant blastocysts is maintained is unclear. We have previously shown that dormant blastocysts, during experimentally induced diapause, exhibit heightened autophagic activation. Activation of autophagy appears to be a crucial adaptive response for survival in the ...

Keywords: oocyte; maturation; meiosis; differentiation; fertilization; pig© 1990 Journals of Reproduction & Fertility Ltd...

The pig industry is confronted with substantial losses due to piglet mortality. With 3-8% stillbirths and generally > 10% preweaning mortality, approximately one fifth of al I fetuses formed fully at the end of gestation die before weaning. Most of these losses occur in the perinatal period. Overall prenatal development (birth weight) and specific prenatal developmental and maturational processes in late gestation are predisposing factors for perinatal losses. Birth weight ...