Symposium review: Progesterone effects on early embryo development in cattle

Area of Science:

• Reproductive Biology
• Dairy Cattle Science
• Embryo Development

Background:

• Dairy cattle fertility is multifactorial, involving oocyte quality and uterine environment.
• Progesterone (P4) is vital for pregnancy establishment and maintenance.
• Inconsistent results exist regarding exogenous P4 supplementation for improving fertility.

Purpose of the Study:

• Review recent findings on embryo-maternal interactions during bovine pregnancy establishment.
• Highlight the role of progesterone (P4) in uterine biology and embryo development.
• Focus on the etiology of pregnancy losses in dairy cattle.

Main Methods:

• Literature review of recent findings.
• Analysis of studies on progesterone's role in bovine reproduction.
• Focus on embryo-maternal interactions and P4's impact.

Main Results:

• Reduced P4 during follicle development is linked to lower fertility.
• Low post-ovulation P4 reduces conceptus growth and pregnancy rates.
• Elevated P4 post-conception can advance conceptus elongation and increase interferon-τ (IFNT) production.

Conclusions:

• Progesterone (P4) significantly influences key events in bovine pregnancy establishment.
• Understanding P4's role in embryo-maternal interactions is critical for improving dairy cattle fertility.
• Further research is needed to optimize P4 supplementation strategies.