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Recipient mares

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More information? See also the frequently asked questions
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Recipient mares

One of the most important factors in a successful embryo transfer is the recipient mare. Equiception maintains a large group of high-quality recipient mares that have been carefully assessed and selected.

More about Recipient mares

More about the recipient mare

The recipient mare plays a crucial role in the success of the embryo transfer. She is responsible for carrying the embryo to term and supporting the foal through its earliest and most vulnerable life stage.

To receive the embryo successfully, the recipient mare must be in exactly the right phase of her cycle. At this moment, her uterus is prepared to accept the embryo, allowing it to implant properly and ensuring hormonal support for the pregnancy.

After the transfer, the recipient mare will carry the foal throughout the entire pregnancy. At birth, she provides the foal with the first milk (colostrum) and takes on the role of caring for and protecting the newborn. A well-matched, healthy, and reliable recipient mare is therefore essential not only for a successful pregnancy, but also for the welfare of the foal.

At Equiception, we work with a large selection of carefully selected recipient mares. These mares are thoroughly evaluated for health, temperament, and fertility, and are ready to carry embryos from our clients’ donor mares.

In some cases, owners choose to use their own mare as a recipient. This is certainly possible and can be a good option. However, we recommend discussing this with your veterinarian to determine whether your mare is suitable for the role of recipient.

Frequently asked questions
What are the requirements for a an ideal recipient mare?

Choosing the right recipient mare is essential for a successful embryo transfer. The ideal recipient mare is between 3 and 15 years of age, has a healthy body weight between 500 and 750 kg, and is in good physical condition. Mares over 12 years old should have successfully delivered at least one healthy foal.

It is also important that the mare has a calm and manageable temperament and does not differ in weight by more than 150 kg compared to the donor mare. While mares with a foal at foot can be used as recipients, we prefer not to use mares that have foaled less than 35 days ago in order to maximize the chances of a successful transfer.

Can I use my own mare as a recipient for embryo transfer?

Yes, it is certainly possible to use your own mare as a recipient for embryo transfer. As a client of Equiception, you may choose to have your own mare carry the embryo, provided she meets the key criteria required for a successful transfer.

There are several important considerations when using your own recipient mare:

To give the embryo the best chance of success, the recipient mare should meet certain requirements, such as being between 3 and 15 years old, weighing between 500 and 750 kg, and being in good physical condition. It is essential that the mare is in optimal health to properly support the pregnancy.

You may choose to have your own veterinarian synchronize your recipient mare with the donor mare. Technically, this is possible, but it requires both experience and a bit of luck.                              

Do you prefer to leave it to us? Equiception can also take care of this process for you. 

Relying on just one recipient mare carries some risk. We recommend attempting to synchronise at least two or three recipient mares. This increases the chance that at least one will ovulate at the right time, which improves the likelihood of a successful pregnancy.

While using your own recipient mare can be a good option, the decision should be made carefully to maximize the chances of a successful transfer. Equiception respects your choice, but emphasizes that responsibility for using a non-ideal recipient mare rests with the client. We always recommend considering the potential risks and discussing the plan thoroughly with your veterinarian.

If you’re unsure whether your mare is suitable, or would like advice specific to your situation, feel free to contact us. 

What does fertility management of the recipient mare involve?

At Equiception, we begin preparing our recipient mares in early December by placing them under additional lighting. This light stimulation helps the mares become cyclic earlier in the season, so they are ready to receive embryos.

Although it is possible to use non-cyclic mares treated with hormones, or mares without ovaries, as recipients, pregnancy rates in these mares are lower compared to well-synchronized cyclic mares. This highlights the importance of proper preparation and timing when selecting the right recipient mare.

Embryos are typically flushed between day 7 and 9 after ovulation of the donor mare. They are then transferred into a recipient mare that has ovulated between 4 days after the donor mare  and 1 day before the donor mare. While transfers into recipient mares that ovulate up to 5 days later can still lead to pregnancies, the highest success rates are seen when the recipient ovulates 1 to 2 days after the donor mare.

In some cases, especially when only one recipient mare is available it may be necessary to actively synchronize the donor and recipient mares. In larger groups of recipient mares, synchronization is usually not required, as there are mares ovulating spontaneously on a daily basis, ensuring that suitable recipients are available for embryo transfer.

Careful monitoring of the recipient mare’s cycle is essential. This includes tracking follicular development, the uterine edema pattern, day of ovulation, number of ovulations, corpus luteum development, and any reproductive abnormalities. In addition to cycle timing, the overall quality of the cycle plays a crucial role in selecting the most suitable recipient mare.

When is a mare possibly unsuitable or less suitable as a recipient for embryo transfer?

There are several factors that determine whether a mare is suitable for embryo transfer. While a mare that is currently not in foal may sometimes still be used as a recipient, it is important to first carefully assess her general physical condition. Following this, a thorough reproductive examination is performed to identify any abnormalities that could affect her ability to become or remain pregnant after embryo transfer. If a mare is found to have issues that may reduce her chances of pregnancy, this will impact the success of the procedure.

Mares requiring a Caslick’s procedure are often not ideal as recipients. The presence of uterine fluid, air, or large cysts also significantly reduces the chances of a successful pregnancy. Depending on the severity of these findings, using such a mare for embryo transfer may be too risky

That said, the decision is not always black and white. For example, an older mare with a foal at foot and a single large uterine cyst may still be considered suitable, depending on her overall health and the specific characteristics of the cyst.

However, mares with an active uterine infection should never be used as recipient mares. This poses serious risks to the embryo.

At Equiception, we also limit the number of embryo transfers per recipient mare. A maximum of two to three embryos may be transferred into the same mare per season. If the mare fails to become or remain pregnant after multiple attempts, she will no longer be used as a recipient.

Finally, it is essential that the mare is in good health and physical condition. Mares with ongoing health issues or poor body condition should not be considered for embryo transfer.

If you have any doubts or questions about your mare’s suitability as a recipient, please don’t hesitate to contact us. We are happy to help you make the right decision.

 

What should I consider when buying a recipient mare?

When purchasing a recipient mare, there are several important factors to consider to ensure you choose a healthy, suitable mare that can successfully carry an embryo. Below are the key points to keep in mind:

1. Age and health

  • Age: The ideal recipient mare is between 3 and 15 years old. Mares over 12 should have successfully carried and delivered at least one healthy foal. Older mares can still be used, but success rates may decrease with age.
  • Health: The mare should be in excellent physical condition. A full health check is essential, including a reproductive exam. Health problems such as chronic lameness can lower the chances of a successful pregnancy. Also performing a dental check is essential to identify potential problems

2. Body weight

  • The recipient mare should weigh between 500 and 750 kg, and her weight should not differ by more than 150 kg from the donor mare. Mares that are too light or too heavy may have more difficulty carrying a pregnancy.

3. Reproductive and physical history

  • It’s important to know if the mare has successfully carried a foal in the past.
  • Mares that have had a Caslick’s procedure are usually less suitable.
  • Also check for past uterine issues such as fluid, air, or cysts, as these can reduce pregnancy success rates.

4.  Cycle and fertility

  • The mare should have a regular and healthy reproductive cycle. If she has trouble coming into heat or maintaining pregnancies, this may affect her suitability.
  • If there is any doubt about her fertility, a veterinarian should assess her for reproductive abnormalities that could interfere with pregnancy.

5. Character and stable behavior

  • The mare should be easy to handle and have a calm character. Stress during embryo transfer can reduce the chances of success. She should also be free of stable vices/unwanted stable habits. 

6. Cycle synchronization

  • The recipient mare’s cycle may need to be synchronized with the donor mare’s. Make sure the mare is suitable for this process and responds well to hormonal treatments.

7. Future use

  • Think about how often you plan to use this mare in the future. It’s wise to choose a mare that is not only suitable for one cycle but can be used multiple times as a recipient.

8. Veterinary advice

  • Always have the mare examined by a veterinarian experienced in reproduction and embryo transfer. Equiception can support you in this process and provide a thorough evaluation, helping you make a well-informed decision.
What are the costs of renting a recipient mare?

Renting a recipient mare involves several costs, including the rental fee itself, the cost of flushing the embryo, and the transfer into the recipient mare. The rental period officially begins once the recipient mare is confirmed 45 days pregnant.

From that moment on, all boarding and medical expenses required to maintain the health of the mare, the pregnancy, and the foal are the responsibility of the client. You may also choose to take out a pregnancy or foal insurance policy for added security.

We work with a rental agreement in which all conditions are clearly outlined.

For the most up-to-date prices, please refer to our pricelist.