Reproduction of the mare: sexual maturity, cycle, gestation and parturition


It is very important to acquire the basic knowledge about reproduction of a mare because they condition the success of the fertilization. How does the animal’s cycle unfold, its gestation and its birth? Answers.

Sexual maturity of the mare

The mare reaches sexual maturity during her first heat, i.e. between 12 and 18 months. It is at this age that the animal begins to secrete hormones and that ovulation causes in it changes physical and behavioral signals to the male that she may be fertilized. However, it is important to separate the mare from the male after her first year as, although possible, reproduction of the young equines is not recommended. Namely, even if the female is in heat, she does not reach her maximum growth until around 4 years old.

The ovarian activity of the mare

The mare’s reproductive system adopts a rhythm seasonal : it begins to activate in March to end in October. The increase in the duration of day constitutes a decisive aspect in his sexual receptivity dictated by the photoperiod (which reacts to sunlight). Note that the temperature also plays an important role. During a period of ovarian activity, cycles of 21 days during which will alternate:

  • A phase estrus from 6 to 8 days. The mare is in heat and accepts the stallion. Ovulation occurs between 24 and 48 hours before the end of sexual receptivity;
  • A phase luteal (dioestrus) of 14 days. The female refuses the male because she is preparing for gestation or is about to start her cycle again if she is not pregnant.

The behaviors of a mare in heat

To know if a mare is in heat, it is necessary to observe the modifications behavioral :

  • She often stands still with her rear legs spread;
  • She tilts her Bowl towards the ground, especially if a male is nearby;
  • She constantly lifts her tail to expose her vulva;
  • Flows mucous appear at the level of the vulvar lips;
  • The clitoris is exposed by jerky movements of the vulva;
  • She is more nervous than usual, neighs and urinates frequently.

Techniques used for mating

Natural or sophisticated, three methods breeding are generally used in horses.

  • The climb freely is carried out in the meadow without human intervention but with minimal supervision;
  • The climb in hand consists of restraining the mare and presenting her with a stallion held in hand. The stallion guides the male’s penis towards the female’s vagina;
  • THE’artificial insemination includes various techniques (fresh semen, frozen semen, embryo transfer, etc.). This method of reproduction provides a wide choice of parents.

Pregnancy diagnosis in the mare

If the mare’s heat does not return, the veterinarian has several processes to confirm pregnancy:

  • A transrectal palpation, from 18e day after the rise, allows to evaluate the size changes at uterine level;
  • A ultrasound performed between 18e and the 21e day can diagnose gestation and from the 55e day, determine the sex of the foal;
  • From blood tests, made from 18e to 21e day, aim to reveal the presence of progesterone. From 40e day, a second 100% reliable test finds the presence of the hormone secreted by the placenta of pregnant mares (equine chorionic gonadotropin);
  • From urine tests, achievable from 120e day until the foal is born, detect the presence of estrogen.

Foaling: the warning signs

In theory, gestation lasts about 330 days (11 months), but in reality it can extend from 320 to 360 days. Then, foaling is announced by different changes in the future mother:

  • A few days before, his udder filled with milk and the udders swell;
  • The wax from the udders begins to flow;
  • The mare looks at the flanks as if she was suffering from colic;
  • She frequently wags her tail, around in circles ;
  • Her vulva and birth canal relax, exposing more of the base of the tail;
  • The vaginal opening gets bigger;
  • During the phase of contraction, the mare fidgets, sweats, hits herself in the stomach, lies down and gets up constantly. Do not disturb her at the risk of stressing her and delaying the birth.

The birth in the mare

Birth begins with the loss of amniotic liquid. Most of the time, the foal mare upright and expels its young quickly, between 5 and 30 minutes maximum. Normally, the forelimbs come first, then come the head and the rest of the body. The umbilical cord breaks at the exit and failing that, the mare chews it and cuts it. It must be disinfected using a dye-based solution.‘iodine. The newborn is covered with a transparent membrane which tears on expulsion and which the mother licks to help her foal out. This phase is an important affective process which, moreover, stimulates breathing of the little one and its rising. After 4 hours, he should be standing and having started the suckling. The very first breast milk provides her with the antibody essential to fight against diseases until the development of its immune system. If the newborn has not suckled within 24 hours following the birth, do not hesitate to contact your veterinarian for advice. If the birth went well, it remains only to admire the tender complicity which will be tied between the mare and her foal.