HOW LONG IS MY MARES HEAT CYCLE ??
The entire mare estrus cycle is, on the average, 21 days in length. Her actual "heat" cycle, when she displays signs of "horsing", and is most receptive to the stallion, lasts about 7 days. A mare will ovulate, or release an egg into her reproductive tract to complete this heat period.  It is approximately 14 days from ovulation until she begins her next heat cycle. Fertile estrus cycles can range from 16 to 30 days or more, so a variability in length is not unusual.

IS THERE A SHOT THAT WILL BRING MY MARE INTO HEAT ??
Yes, but it must be given at the proper time in the estrus cycle to be successful. The "shot", called prostaglandin (Lutalyse in some cases), should only be given to a mare that has been OUT OF HEAT for at least 5 days. If properly used, most mares will show signs of "horsing" by day 3 and will ovulate by day 8. Prostaglandin can be a very powerful tool for breeding management when used as directed.

WHEN CAN YOU TELL IF MY MARE IS PREGNANT ??
An equine embryo can be located with ultrasound (if you look really hard) as early as 9.5 to 10 days post ovulation. To increase the accuracy of diagnosis, we routinely examine mares At 12-14 days.  This is also an excellent time to check a mare for twin embryos.  We do another exam at 35-38 days to monitor fetal development, and after 45 days, we can diagnose your mare "safely in foal".