In vitro fertilization and embryo development in pigs

Area of Science:

• Reproductive Biology
• Embryology
• Animal Science

Background:

• Significant advancements have been made in in vitro maturation (IVM) and in vitro fertilization (IVF) for pig embryo production.
• Polyspermic penetration remains a key challenge, impacting the success of in vitro-matured oocytes.
• Early in vitro culture methods faced limitations, with embryos often arresting at the four-cell stage.

Purpose of the Study:

• To review the current state of in vitro-produced (IVP) pig embryo development.
• To identify persistent challenges in IVP, specifically polyspermy and embryo quality.
• To highlight areas for future research to improve large-scale pig embryo production.

Main Methods:

• Review of existing literature on pig IVM, IVF, and embryo culture techniques.
• Analysis of factors influencing polyspermy, including boar variation and IVF protocols.
• Comparison of in vitro-produced (IVP) and in vivo-derived pig embryo development and morphology.

Main Results:

• While culture media now support blastocyst development, IVP embryo blastocyst rates vary significantly.
• Differences in morphology and cell numbers exist between IVP and in vivo-derived blastocysts.
• Surgical transfer of IVP embryos yields acceptable pregnancy rates, but polyspermy and poor survival hinder large-scale production.

Conclusions:

• Polyspermy and suboptimal embryo quality are major obstacles to efficient large-scale in vitro pig embryo production.
• Further research is needed to enhance oocyte and embryo quality.
• Developing improved IVM, IVF, and embryo culture techniques is essential to minimize polyspermy and boost embryo survival.