Early embryonic development, assisted reproductive technologies, and pluripotent stem cell biology in domestic mammals

Abstract

Over many decades assisted reproductive technologies, including artificial insemination, embryo transfer, in vitro production (IVP) of embryos, cloning by somatic cell nuclear transfer (SCNT), and stem cell culture, have been developed with the aim of refining breeding strategies for improved production and health in animal husbandry. More recently, biomedical applications of these technologies, in particular, SCNT and stem cell culture, have been pursued in domestic mammals in order to create models for human disease and therapy. The following review focuses on presenting important aspects of pre-implantation development in cattle, pigs, horses, and dogs. Biological aspects and impact of assisted reproductive technologies including IVP, SCNT, and culture of pluripotent stem cells are also addressed.

Use of pluripotent stem cells for reproductive medicine: are we there yet?

“…It is now possible to derive porcine ESCs from in vitro fertilized, in vivo derived, IVF aggregated and parthenogenetic embryos (Park et al 2013). However, in order to derive authentic porcine ESCs, the current culture conditions still require optimization (Hall et al 2013). Further, the time point for porcine ESC isolation from pre-implantation embryos needs to undergo an in-depth investigation to determine the ideal time point for derivation.…”

“…Although similar to mESClike parameters, these equine ESCs were unable to form teratomas in vivo (Li et al 2006). In addition, equine ESC-like cells were reported to be produced upon enzymatic ICM isolation from parthenogenetic, somatic cell nuclear transfer and in vivo derived embryos (Desmarais et al 2011;Hall et al 2013). However, after careful examination, these cells were deemed to be trophoblast stem cells and not authentic equine ESCs.…”

“…They were also capable of undergoing efficient differentiation into all the three germ layers when differentiated as EBs. Although these ESC lines were capable of forming teratomas upon transplantation into immunodeficient mice, their capacity to form chimeras and contribute to germ line transmission is yet to be assessed (Hall et al 2013). An interesting property of canine ESCs is that they are dependent on both naive and primed signalling pathways, supported by LIF and bFGF, respectively (Wilcox et al 2009).…”

Efectos de los RNAm maternos sobre la maduración del ovocito y el desarrollo embrionario temprano en mamíferos

“…En el campo de la reproducción animal, la identificación y caracterización de los genes que participaran en la regulación del crecimiento del ovocito y de la transición del ovocito al embrión, son requeridos para entender los mecanismos de maduración, fertilización y desarrollo embrionario de animales domésticos como el bovino (1)(2)(3) . El desarrollo potencial de un embrión depende del ovocito del cual se originó; por lo tanto el proceso de maduración por medio del cual el ovocito adquiere competencia, es crítico para generar embriones eficientes que originen individuos sanos después de ser implantados (4) .…”

“…In the field of animal reproduction, the identification and characterization of genes that participate in the regulation of the oocyte growth and the transition of the oocyte to embryo, are required to understand the mechanisms of maturation, fertilization and embryonic development of domestic animals such as the bovine (1)(2)(3) . The potential development of an embryo depends on the oocyte, from which it originated; therefore the mature process by means the oocyte acquires competition, is critical to generate efficient embryos that originate healthy individuals after being implanted (4) .…”