Rebreeding Your Horse on Foal Heat

Get the facts about this common horse breeding practice.

Get the facts about this common horse breeding practice.


Our 20-year-old mare has had four foals without any problem.

She is due to foal this year after finally conceiving with on-farm AI collection and direct insemination.

Barring any foaling problems, should we rebreed on her foal heat or wait for the next cycle?

Get answers about pregnant mare care and breeding your horse with AQHA’s Horse Reproduction report, available for download for just $9.95.


Breeding on foal heat is a subject that will elicit many opinions. With foal heat breeding, the pregnancy rate is lower than on subsequent cycles. The pregnancy loss rate is higher than mares bred on subsequent cycles. A majority of the data for these statistics comes from large commercial breeding farms. A study performed at Texas A&M University looked at foal heat breeding in the population of prison mares. These mares are selected for fertility and bred to stallions of good fertility. In that study, there was no difference with pregnancy rate if the mare was bred on foal heat or if foal heat was skipped and the mare was bred on subsequent heats.

I would skip foal heat and breed her on the subsequent cycle. If she is due to foal later in the year, you can shorten the interval to the second heat with the use of prostaglandin. I would suggest having your veterinarian palpate and ultrasound the mare’s uterus when she is in foal heat to make sure it is in good shape. – Pete Sheerin, D.V.M., Lexington, Kentucky

Learn more about breeding on foal heat and other horse breeding issues with the Horse Reproduction report.

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8 thoughts on “Rebreeding Your Horse on Foal Heat”

  1. I was asked by several people if there is a cure or a way to stop a horse from grinding their teeth together while being ridden. I’ve noticed this primarily when the horse is collected and on the bit. I must also relate that this has been mostly when trying to retrain a race horse to dressage or pleasure.

  2. Tony
    I would think teeth grinding is his way of telling you he is unhappy. Possibly he is not ready for that level of riding and it would be best to ask for collection/on the bit for shorter periods of time and try to reward him when he performs without grinding his teeth. The good thing is he isn’t bucking because he is unhappy. Could this be a habit he has picked up, similar to weaving, and grinds his teeth more than you know.

  3. Thanks Mary

    I believe that your suggestion is a little over 100% correct. I will personally work with this horse and will get back to you asap!

    Thanks Tony

  4. After more than 30 years working with horses, I am having problems with a 3 year old gelding that we raised from birth. He has developed a ‘dislike’ of being handled at the poll, ears, and even his forehead and upper mane. I am not aware of injury or infection that would cause him discomfort. This has been building over a period of time. He is easy to catch, halter and saddle. He leads at walk or trot, backs, round pens or lunges easily. The problem is when we want to groom or bridle this area. He then becomes tense and pushy, raising his head above our reach and ‘throws’ his head if you continue the activity. He has not been started riding because of this problem. I recently sent him to a trainer who was made aware of the problem, I picked him back up after a week there as he did not feel they were making any progress with him either. Currently I am trying to work 1-2 times per day (without the halter or bridle) on just rubbing and scratching him, including the problem area as much as he allows. Any other suggestions? Sincerely, Susan Rigon

  5. Funny, I was always told by the vet I worked for that breeding back during the foal heat would yield better results. Personally, I do not practice this.

  6. Susan, After 60 years as a trainer, I’ve developed a bag full of training tips. For your head-shy horse try loping a thin rope (about the diameter of baling twine) as far up on the horse’s neck as possible. Place your left hand on the bridge of the horse’s nose and simultaneously place pressure on the nose and pull downward on the rope. Do not place excessive pressure because the horse will fight. Hold that pressure until the horse dips it’s head, then instantly release. Continue this pressure until the horse understands what you want, then lengthen the time of the pressure to keep the horse’s head down to your work level. Hold for 2 seconds, then for 4 seconds, etc. Now attempt to bridle the horse while keeping pressure from the rope over the horse’s neck. When he raises his head, bring his head down until you can successfully bridle the horse. If that doesn’t work, we’ll have to look into that bag for another trick.

  7. I would love to know about TOXIC COLESTROM.I was told every mare should be tested once she has milk. Thanks J.

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