ICSI Services
Ultrasound video of a developing ICSI fetus at 45-50 days of pregnancy after transfer of a vitrified ICSI-produced embryo approximately 40 days after non-surgical embryo transfer.
Horse breeders are well aware that for every successful embryo transfer pregnancy and subsequent foaling, numerous embryos can be lost. This is due to failure of maturation of eggs, fertilization, or embryo death before transferring to a recipient along with failure to establish or maintain a pregnancy, or a result of chromosomal defects. This process is costly to horse breeders and poorly understood by equine scientists.
In the past 10-15 years Equine Assisted Reproductive Technology (EqART) has experienced significant growth for breeders, particularly with the advent of intracytoplasmic sperm injections into matured eggs (ICSI). UC Davis’ tradition of serving horse breeders and our long-standing relationship with the horse industry in California and around the world led to a wide range of advances in equine health including Equine Reproduction.
We are pleased to announce that our laboratory and the Equine Reproduction Service at the UCD Veterinary Teaching Hospital are offering this unique service to produce equine embryos. We offer a variety of embryo services including transvaginal ovarian aspiration of eggs, ICSI in vitro fertilization, freezing embryos, and embryo biopsy services, and many others. We are also receiving shipped oocytes from anywhere in the US for ICSI production of embryos for storage and shipping for embryo transfer.
Our Success is Your Success! We have been producing horse embryos using ICSI and we have produced several foals using this procedure. We typically obtain a 50% egg maturation rate and of those eggs that mature, we typically can expect about 30% of sperm-injected eggs to become transferrable blastocysts that we can ship or freeze for later transfer to recipients.
How does ICSI work?

TVA/OPU: In vitro embryo production starts with the collection of immature eggs from the donor mare in a procedure named Ovum Pickup (OPU) / Transvaginal aspiration (TVA).
Shipping: Retrieved eggs are placed in a ‘Holding medium’ and transported within 24 hrs. to the ICSI lab in a special device designed to keep the internal temperature to ~22C.
In vitro Maturation: Immature oocytes are placed in a special maturation medium and cultured in the incubator for about 24-27 hours. Usually, only about 66% of oocytes will mature and be suitable for fertilization with ICSI.
ICSI: Matured eggs are injected with sperm from the selected stallion under the microscope using micromanipulators.
Embryo Culture: ICSIed eggs are placed in a special culture medium and placed in the Non-invasive time-lapse incubator where they start developing. About 30% would develop and reach the Blastocyst stage within 7-10 days.
Vitrification or Transfer: Once an embryo has reached the blastocyst stage, it needs to be transferred into a recipient mare (properly cycled), OR it needs to be frozen in a technique called ‘Vitrification’ and stored in liquid nitrogen for posterior thawing an ET.
This whole process could takes about 9 to 11 days.
OUR ICSI EMBRYO SUCCESS RATES
The table below demonstrates our lab’s ICSI Success rates:
Oocyte maturation rate | 66% |
Cleavage rate after sperm injection | 66% |
Blastocyst rate | 34% |


Traditionally ICSI has only been available in a few specialized laboratories in North American where established centers for ART are located. Through the work of Drs. Stuart Meyers and Pouya Dini, California breeders can now readily access ICSI technology at UC Davis, avoiding costly and long-distance transportation of mares and stallions.
Of course, our research program and training of future equine veterinarians and embryologists is one of our primary missions at UC Davis. The expansion of EqART to include clinical services to horse owners also provides a foundation from which to build an understanding of egg and ovarian function that will take understanding equine reproductive health to new and unexplored levels. This research will serve to benefit mares as well as stallions and improve the production of foals significantly and benefits research training of graduate students, postdoctoral fellows, residents, and visiting scholars. Research and service to horse owners are thus mutually beneficial and support our research program!
Click here to download more information about ICSI and embryo production at UC Davis (pdf)