The pregnant mare

Routine Care

We are happy to advise on all aspects of routine management of the pregnant mare, including feeding, exercise, vaccination and worming.

We recommend that the health of the equine pregnancy is monitored regularly, particularly during the first few weeks, when the embryo is most fragile.

Once beyond about 45 days, the equine foetus is much less at risk, and unless there is reason for concern, such as early milk production, vaginal discharge or recurrent colic, mares can generally be generally left to their own devices during pregnancy.

Recommended Dates for Pregnancy Checks 

Twin pregnancy in the horse generally ends in disaster and all efforts should be made to avoid a twin pregnancy being carried to term. Unfortunately, twinning is also reasonably common, particularly in Thoroughbreds. Early pregnancy diagnosis allows twins to be detected promptly. One twin can be terminated at this stage, usually allowing the other to develop healthily to term.

The most reliable method of early pregnancy diagnosis is per rectum ultrasound examination. Blood tests are unreliable at this stage, and cannot differentiate between a single and multiple pregnancies.

We recommend a minimum of two pregnancy scans;  the first between 14-18 days and second between 28-35 days post covering.

A single scan is not reliable to diagnose either non-pregnancy or twinning. Stallion sperm can remain viable within the mare for up to 7 days. Therefore a mare scanned at 16 days after covering may be carrying a pregnancy that is only 9 days old, and hence too small to see. Scanning is less reliable when the date of covering/ovulation is unknown.

Foetal Sexing 

For those wanting to know whether to paint the foaling box blue or pink, or planning for future breeding programs, the sex of the unborn foal can be determined with a high degree of accuracy. This is best carried out between 65-75 days after mating.