Relationship Between Ovulation and Body Temperature in the Mare: A Preliminary Study.
Authors: Auclair-Ronzaud Juliette, Barrier-Battut Isabelle, Bozec Jeanne, Potier Paul-Henri, Dubois Cédric, Wimel Laurence
Journal: Journal of equine veterinary science
Summary
# Editorial Summary: Body Temperature Monitoring and Ovulation Detection in Mares Reliable ovulation detection remains a cornerstone of efficient equine reproduction management, yet current best practice relies on transrectal ultrasonography—a method that demands veterinary expertise, mare handling, and significant cost. Auclair-Ronzaud and colleagues investigated whether automated body temperature monitoring using implanted microchips could provide a non-invasive alternative by tracking nine reproductive cycles with concurrent ultrasonography, serum hormone analysis (oestradiol-17β and progesterone), and continuous temperature recording at 10-minute intervals. Whilst overall daily temperature patterns remained consistent throughout the reproductive cycle, the researchers identified cycle-phase-specific temperature changes: ovulation triggered a sharp rise of 0.51–0.92°C occurring between 04:30 and 08:00, and the early luteal phase showed further elevation of 0.29–0.60°C between 10:30 and 16:00. These findings suggest implanted temperature sensors could offer equine practitioners a practical tool for non-invasive cycle monitoring, potentially reducing reliance on repeated veterinary examinations; however, the authors acknowledge that larger-scale studies examining complete cycles are essential before drawing firm clinical recommendations. For breeding operations and competition yards where labour costs and handling stress are significant concerns, further validation of this technique could prove economically and welfare-wise advantageous.
Read the full abstract on PubMed
Practical Takeaways
- •Automated temperature monitoring via implanted chip may offer a low-cost alternative to daily transrectal ultrasound for ovulation timing in breeding programs
- •Temperature increases occur at specific times of day (early morning for ovulation, mid-day for luteal phase entry), so monitoring must account for hourly variation rather than just daily averages
- •This preliminary work suggests promise but requires larger, more comprehensive studies before implementation as a standard practice tool
Key Findings
- •Body temperature increased by 0.51°C to 0.92°C at ovulation compared to end of follicular phase, occurring between 04:30 and 08:00
- •A significant temperature increase of 0.29°C to 0.60°C was measured during early luteal phase between 10:30 and 16:00
- •Daily body temperature patterns did not differ between reproductive cycle phases, but hourly-specific temperature differences were identified
- •Body temperature monitoring via implanted identification chip with temperature sensor shows potential as a non-invasive tool for ovulation detection in mares