In vitro culture and interferon-tau secretion by ovine blastocysts

Area of Science:

• Reproductive Biology
• Embryology
• Biochemistry

Background:

• Ovine embryo culture is crucial for reproductive technologies.
• Interferon-tau (IFN-tau) is a key pregnancy recognition signal in sheep.
• Understanding IFN-tau secretion dynamics during in vitro culture is vital.

Purpose of the Study:

• To assess long-term culture of ovine blastocysts.
• To evaluate interferon-tau (IFN-tau) secretion from cultured ovine blastocysts.
• To develop and validate assays for IFN-tau measurement.

Main Methods:

• Surgical collection of ovine embryos (days 7-10).
• In vitro culture in supplemented or standard DMEM.
• Daily monitoring of embryo morphology, diameter, and IFN-tau secretion via ELISA and antiviral assays.

Main Results:

• Ovine blastocysts cultured in DMEM without BSA showed variable survival and growth.
• Day-10 embryos exhibited significantly larger diameters after 7 days of culture compared to day-7 embryos.
• A higher percentage of day-8 embryos secreted IFN-tau earlier in culture than day-7 embryos.
• IFN-tau secretion levels varied, not correlating with embryo morphology.

Conclusions:

• Long-term culture of ovine blastocysts is feasible but influenced by culture medium composition.
• Day-8 embryos demonstrate a more robust IFN-tau secretion profile in vitro.
• Developed assays provide tools for assessing embryo viability and function through IFN-tau measurement.