FAQ

Equine ICSI (Intracytoplasmic Sperm Injection) is an assisted reproductive technique in which a single sperm cell is injected directly into an oocyte (egg) under laboratory conditions. The fertilized oocyte is then cultured into an embryo and either transferred into a recipient mare or cryopreserved.

InFoal, Inc. provides laboratory-based equine ICSI services for mares and stallions that cannot be bred using conventional methods.

Equine ICSI is commonly recommended when:

• A stallion has low sperm numbers or poor motility

• Only frozen, limited, or deceased stallion semen is available

• A mare cannot carry a pregnancy due to athletic demands or uterine issues

• Traditional embryo transfer or insemination has failed

Research The first question most mare owners ask is, “Will the ICSI procedure damage my mare's ovaries?” That was the first concern I had when I started performing this procedure in 2006. We first learned to aspirate follicles on recipient mares, which was all we did for 2 years. First we were aspirating mature follicles through the flank approach, with a trocar and needle through a surgically prep on the donors flank. The needle was introduced into the follicle without ultrasound guidance. With that procedure, I worried about damaging the ovary with the needle, accidentally puncturing the bowel or other organ, infection or hemorrhage. After about 300 of those procedures, the only problem we had was 2 abcesses in the abdominal wall where the trocar was introduced. After modifying the procedure to inject penicillin into the trocar tract after the aspiration, no more abcesses occurred. I ultrasounded the donors the following day, I was worried about hemorrhage. There was never more hemorrhage than occurred with a hemorrhagic ovulation. ​ Then we began ultrasound guided aspiration of small follicles through the anterior vagina with an aspiration probe and a long needle. This approach allowed us to enter the ovary from the medial surface, which is much safer because the oviduct is located on the lateral side. A concern was that the aspiration needle would penetrate the oviduct causing blockage from scar tissue, but this cannot happen with the vaginal approach because the oviduct is on the far side of the ovary. The next concern is actual damage to the ovary from repeated penetration of the aspiration needle, both during one session (can be 3 to 5 actual needle entry points depending on the number and location of the follicles in the ovary), and the accumulated damage from repeated aspirations over time. The following article was published in 2005, investigating that question and finding no negative effects on fertility.

Conventional InVitro Fertilization is a natural form of fertilization. The sperm sample is activated and oocytes are incubated directly in the sperm media. Mother Nature selects the sperm and the mechanics of fertilization occur naturally.

InFoal, Inc. will be offering this process on a limited basis this year.

We have produced many ICSI embryos from 2 yr old fillies.

No, there are many veterinarians around the country now that can aspirate eggs from mares and send them to an ICSI laboratory.

We do aspirate here, inject the eggs, mature them in the incubator and transfer them into recipient mares.

InFoal, Inc. has a mobile hospital unit to come to you and aspirate your mare in a clean environment. A laboratory for search and incubation is contained in the front of the trailer to allow hospital conditions for the entire process.

With the success of freezing ICSI embryos, we can now transfer your embryo into your mare. Whether the donor mare or your recipient mare, the embryo seldom develops on the day the recipient is ready to receive it. However, once the embryo is frozen, it can be thawed and transferred when the recipient mare is ready.

You have a choice – transfer or freeze.

TRANSFER – transferring a fresh embryo requires a recipient mare that ovulated 4 to 5 days ago for a successful transfer. If there is one available, either from our herd, your own recipient or another ET facility, a fresh transfer is possible.

FROZEN – freezing ICSI embryos has become a very successful option if done properly. Since moving to Texas, we have learned that thawing and shipping frozen embryos to another facility does not work well. However, when embryos are thawed in our lab and transferred here without shipping them, the pregnancy rates are equal to the pregnancy rates of fresh ICSI embryos.

She is considered safely in foal at 45 days. During this time, when she is at the clinic, we will perform periodic pregnancy checks and she will be on a daily progesterone supplement. When she is confirmed pregnant at 45 days, you may take her home that day. Recipients can be taken sooner at the owners discretion.

Yes. We will perform a breeding soundness exam and if we can use her in the embryo program again, you will receive a refund if they are still breeding sound.

We highly suggest keeping the recipient mare on some form of progesterone, such as Altrenogest or Regu-Mate until at least 120 days regardless of her own progesterone level.

Cost will vary depending on where you have each part of the process performed. Basicly, there are three steps –

1.Aspiration the mare – collecting the oocytes from the donor mare's

ovary.

2. Injecting the oocytes – laboratory process of mechanically placing

the sperm inside the egg with a microscope and maturing the embryo.

3. Transferring the embryo into a recipient mare.

Each step may be performed at different locations, by different people. There are many facilities perform aspirations, there are only a few labs that perform the injection and culture, and there are several locations that provide recipient mares. Costs and results will vary depending on the combination of these three services.

We provide all three steps here. You can drop your mare off in the morning and pick her up that afternoon. We will aspirate her and the oocytes go directly into our lab. The injection and culture will be performed in our new state of the art laboratory by Dr Beck, who helped perfect the procedure 20 years ago. Once the embryo is mature, it will be transferred into one of our 1000 recipeint mares which have been monitered daily to insure proper timing and a healthy uterus.

We recieve oocytes from other aspiration facilities, and ship finished embryos to other tranfer locations. However, we achieve consistently higher success when all steps are performed in the same place.

Our cost for a 45 day pregnant recipient mare is $6300 if the entire process is performed at InFoal, Inc. That does not include a $1500 refundable deposit on the recipient mare.

Pricing is included in our contracts. Please contact us for more information.

InFoal, Inc. generally reserves the recipient mares for client embryos.

ICSI - the sperm is selected and injected into the egg by Dr. Beck.

cIVF - the sperm is selected by Mother Nature and fertilizes the egg naturally.

Otherwise, the aspiration, maturation and culture post-fertilization

are all the same.

We have performed over 4000 aspiration since we started doing ICSI in 2006. Originally, the follicle was approached thru the flank with an 8 inch 12 gauge needle with no ultrasound guidence. Only big preovulatory follicles were aspirated.

Once the vaginal approach was perfected, the numbers of oocytes (eggs) increased dramatically. This year (2025) we have performed over 700 aspirations, averaging 12.6 eggs per procedure.

Yes. Performance mares can undergo oocyte aspiration while continuing training or competition. Because the mare does not need to carry the pregnancy, ICSI allows genetic production without removing the mare from performance schedules.