Advances in in vitro production of sheep embryos

Abstract

Sheep is an important livestock in the world providing meat, milk and wool for human beings. With increasing human population, the worldwide needs of production of sheep have elevated. To meet the needs, the assistant reproductive technology including ovine in vitro embryo production (ovine IVP) is urgently required to enhance the effective production of sheep in the world. To learn the status of ovine IVP, we collected some publications related to ovine IVP through PubMed and analyzed the progress in ovine IVP made in the last five years (2012–2017). We made comparisons of these data and found that the recent advances in ovine IVP has been made slowly comparable to that of ovine IVP two decades ago. Therefore, we suggested two strategies or approaches to tackle the main problems in ovine IVP and expect that the efficiency of ovine IVP could be improved significantly when the approaches would be implemented.

Effect of Wild Marjoram (<i>Origanum vulgare</i>) Plant Extracts on Capacitation of Sheep Spermatozoa <i>in Vitro</i>

“…Healthy embryos require good quality oocytes [1]. Three of the key issues encountered within culture systems are the intrinsic quality of the immature oocytes [43] oxidative stress [44] and substandard culture medium [45].…”

“…Therefore, increasing productivity using the appropriate modern technologies including in vitro embryo production (IVEP) techniques is necessary. In the future, IVP systems could play a crucial role in sheep production by accelerating sheep breeding and reinforcing the production po-tency [1]. In vitro embryo production is a multi-step process consisting of: 1) In vitro maturation (IVM) of oocytes, 2) In vitro fertilization (IVF), and 3) In vitro culture (IVC) of zygotes up to the blastula stage [2].…”

Towards Improving the Outcomes of Assisted Reproductive Technologies of Cattle and Sheep, with Particular Focus on Recipient Management

“…As the industry moves to increase the number of lambs produced, and increase the size of the national ewe flock, the effective implementation of assisted reproductive technologies becomes increasingly important. From the second half of the 1980s, in vitro production of embryos (IVP) became a widely used technology within livestock industries [15]. IVP involves three main procedures, initiated from the collection of immature oocytes from the ovary, from either stimulated or unstimulated animals.…”

“…Ultimately, the aim of the development and implementation of these protocols is to increase the rate of genetic gain within Australian livestock industries, thereby increasing flock numbers. The oocytes undergo in vitro maturation (IVM), in vitro fertilisation (IVF) and in vitro culture (IVC) [15]. This generates an in vitro produced embryo which is then transferred into a recipient animal [15].…”

“…The oocytes undergo in vitro maturation (IVM), in vitro fertilisation (IVF) and in vitro culture (IVC) [15]. This generates an in vitro produced embryo which is then transferred into a recipient animal [15]. Embryo transfer (ET), MOET, and IVP from either mature (MIVET), or juvenile animals (JIVET) are the key ARTs under investigation.…”