C
Clarity News Hub

How often do mares come season?

Author

Emma Payne

Published Jan 10, 2026

So-called periods of heat mirror the mare's ovarian activity. This occurs from April to October in general, and results in a succession of cycles lasting 21 days on average.

What are the signs of a mare in season?

Mare cycles generally last 21 days with them expressing signs of heat for 4-7 days. Estrus is expressed outwardly by; raising the tail, frequent urination, “winking” or eversion of the vulva, squealing, and posturing which entails widening the back legs while rounding the hind quarters.

Do mares go into heat every month?

Most mares experience heat cycles during spring and summer months, when days are longer and warmer. On average, your mare will be in heat (estrus) for six days, then out for 15 days in a recurring cycle. During heat, her developing follicles release the hormone estrogen.

Are mares in season all year?

Mares are 'long day breeders' meaning that they usually breed during late spring, summer and early autumn. Mares are also termed seasonally polyoestrous breeders, that means they cycle (have oestrous cycles) many (poly) times per year but only during the breeding season (seasonally).

At what age do mares stop coming into season?

Generally, mares are past their reproductive prime when they reach 15 to 16 years old. There are mares that can carry and deliver healthy foals into their 20s, but the majority of them have had multiple successful pregnancies before.

32 related questions found

Do mares go through menopause?

Unlike humans, mares do not undergo menopause, although their eggs do deplete eventually. Ball emphasized that a mare's actual age and reproductive age are not the same. The reproductive age is dependent on the number of oocytes (eggs) populated in the mare's ovary at birth.

Can a gelding bring a mare into season?

To answer your question specifically, exposure to another horse, be it a gelding, stallion or mare, does not necessarily induce estrus. A mare will cycle on her own, depending on her geographic location, when the day length is long enough to stimulate her natural cycle.

Do mares cycle in winter?

Most mares are seasonally polyestrous and cycle when the length of daylight is long. Anestrus occurs during the winter when daylight length is short.

How many times a year do mares go into heat?

As a general rule, horses have their first heat cycle when they turn one year, and the cycle stops when the horse is about 20 years old. The cycle lasts three weeks, and the horse will be in heat for two to five days, but this may vary slightly depending on factors such as their age, season, and location.

Why is my mare in season in winter?

During the winter when the ovaries are inactive, circulating levels of the hormone progesterone are very low. This lack of progesterone may lead to the mare appearing in season throughout the winter.

Why is my mare always in season?

Mares that continue to come into heat or have more frequent heat periods may be suffering from ovarian tumors, infection, or other disease conditions. A veterinary examination can uncover these problems that may affect breeding soundness.

Can I ride my mare when she is in heat?

Many mares become very sensitive when they're in season but if she's showing you she's in pain when you ride her, it may be time to get her some help. When mares come into season, they'll have significant hormonal changes that can result in discomfort and mood swings.

Why is my mare not coming into season?

Untreated mares may remain out of heat and will not cycle for up to 2 to 3 months. Other, less common causes of failure to cycle include Equine Cushing's Disease, chromosomal abnormalities, and adminis- tration of certain hormones.

Do mares pee more when in season?

During the peak of estrus, the mare may sniff, lick, or nuzzle the stallion. A mare in heat will also urinate frequently, particularly if a stallion is teasing her to test her receptiveness. She is also likely to raise her tail and assume a breeding stance.

How many days are between mares in heat?

The average length of the estrous cycle is 21 to 23 days (from one ovulation to the next). Estrus – Refers to “heat,” the period when the mare is receptive to the stallion (usually lasts about five to six days).

How do you deal with a mare in heat?

Progesterone has been shown to be the most effective hormone to suppress a mare's heat, but estradiol (a form of estrogen) and oxytocin can also be effective. Following examination, your veterinarian will be able to recommend the ideal hormone therapy treatment plan for your mare.

Why is my mare so mean?

“It may be due to subtle changes in hormonal levels. There can also be an obvious physical problem like an ovarian tumor which causes the production of male hormones. Ovarian bleeding, urinary tract infections, back pain, and vaginitis (vaginal inflammation) can be other reasons a mare may alter her behaviour.

Can you breed a 30 year old mare?

In general, female horses can breed until they are 25 years old, and male horses can breed up to 30 years old. But some horses may stop breeding either much younger or older depending on their health, fertility, and history.

How long is a mare pregnant?

On average, a mare's pregnancy lasts 338 to 343 days. Labor and delivery are generally very uneventful.

How can you tell if a horse is in heat?

While each horse is unique, there are several signs that a horse is in heat. Some of the most common signs include tail raising, frequent urination, anxiety, increased interest in stallions, squealing, signs of aggression, unpredictable behavior, and looser bowel movements.

What is teasing a mare?

Determining the estrus cycle starts in early December with daily teasing. Teasing is when a teasing stallion is put in close proximity with a mare so that one can look for signs of ovulation.

Why do mares kick stallions?

A mare may kick at a stallion if it is not receptive to being bred. This defensive instinct may explain why some horses kick when they become alarmed—such as when a person, dog, or another animal 'pops into view' behind the horse.

Can you ride a broodmare?

It is generally considered safe to ride a mare during the first six to eight months of pregnancy. The foal does most of its growing during the last trimester, so it is best to reduce activity at this point.

Is 20 too old to breed a horse?

Mares can continue to produce foals well into their late teens or early to mid 20's. However, mare owners should realize that the prognosis for fertility of an older mare decreases each year.

Can a horse tell if a woman is on her period?

When we think about the reproductive cycle of a human woman, the most 'visible' part of that cycle is menstruation. That isn't the case for a mare – a mare's 'period' cannot be seen since she just absorbs the discharge.