CO2 concentration affects in vitro pig embryo developmental capacity

Area of Science:

• Reproductive Biology
• Developmental Biology
• Animal Science

Background:

• In vitro embryo culture requires precise environmental control, with gas atmosphere being a critical factor.
• Carbon dioxide (CO2) concentration influences embryo development, but optimal levels for porcine embryos are not fully established.

Purpose of the Study:

• To investigate the impact of varying CO2 concentrations on the pre-implantation developmental capacity of pig embryos produced through parthenogenesis, IVF, and ICSI.

Main Methods:

• Porcine embryos from parthenogenesis, IVF, and ICSI were cultured in vitro under four different CO2 concentrations (3%, 5%, 10%, 15%).
• Cleavage rates and blastocyst development on day 7 were assessed to evaluate developmental capacity.

Main Results:

• The highest cleavage rates for all embryo types were observed at CO2 concentrations below 5%.
• No significant difference in oocyte cleavage rate was found between 3% and 5% CO2 for ICSI embryos.
• Blastocyst output significantly decreased, reaching 0% at 15% CO2 for all embryo types.

Conclusions:

• CO2 concentration is a key factor influencing pig embryo development in vitro.
• A 5% CO2 concentration appears optimal for maximizing cleavage and blastocyst formation in porcine embryos.
• Both excessively high and low CO2 levels negatively impact embryo developmental potential.