Defined system for in vitro production of porcine embryos using a single basic medium

Area of Science:

• Reproductive Biology
• Animal Biotechnology
• Embryology

Background:

• Previous work established porcine blastocyst production via in vitro fertilization (IVF) and culture (IVC).
• Chemically defined media like porcine gamete medium (PGM) and porcine zygote medium (PZM)-5 were previously used.
• A need exists for a single, defined basic medium for efficient in vitro embryo production encompassing in vitro maturation (IVM), IVF, and IVC.

Purpose of the Study:

• To investigate the effects of basic media and macromolecular components on porcine oocyte in vitro maturation (IVM).
• To develop a defined system for in vitro embryo production using a single basic medium.
• To evaluate the impact of different maturation media on subsequent parthenogenetic activation and IVF outcomes.

Main Methods:

• Porcine immature oocytes were matured in porcine oocyte medium (POM) or modified North Carolina State University (mNCSU) 37.
• Media were supplemented with either porcine follicular fluid (pFF) or polyvinyl alcohol (PVA) as macromolecular components.
• Oocytes underwent parthenogenetic activation or IVF, followed by embryo culture in PZM-5 for 5 days.

Main Results:

• Maturation with mNCSU37+PVA resulted in significantly lower metaphase II progression.
• Cleavage and blastocyst formation rates were reduced in parthenogenetic and IVF embryos matured with mNCSU37+PVA.
• POM+PVA yielded a significantly higher normal fertilization rate, though PVA supplementation reduced blastocyst cell numbers compared to pFF.

Conclusions:

• The choice of basic medium and macromolecular supplement critically affects porcine oocyte IVM, parthenogenetic activation, and IVF success.
• mNCSU37 supplemented with PVA is suboptimal for porcine oocyte maturation and subsequent embryo development.
• A defined system using a single basic medium for IVM, IVF, and IVC is achievable for porcine blastocyst production.