BY KIMBERLY LOUSHIN
Breeding the next generation of equine super stars is no easy feat. The breeding process alone can be complex and stressful, and while assisted reproductive technologies have vastly improved outcomes and allowed mares and stallions with low fertility to successfully breed, the multi-step process often requires numerous laboratories or veterinary clinics to work in tandem. With that comes communication errors, shipping delays and other variables that threaten the viability of the future pregnancy.
But Equigea, based in Summerfield, Florida, is streamlining the process of equine Intracytoplasmic Sperm Injection (ICSI), a technique which fertilizes donor mare eggs with a single sperm. By being the only reproductive center in Florida to handle the process from oocyte and semen collection to birth, Equigea and its employees can ensure tighter quality control, better communication and mitigate the risks of shipping genetic material.
Photo courtesy of Equigea
Equigea is a collaboration between Peterson Smith’s Advanced Fertility Center and Avantea, a world leader in assisted reproductive techniques, which cloned the first horse in 2003. Founded in 2016, Equigea combines Peterson Smith’s veterinary knowledge with Avantea’s technology and techniques to provide comprehensive care. Equigea handles a few hundred ICSI procedures a year, and with its small dedicated staff, clients get a personalized experience. Because Equigea operates out of part of the Peterson Smith Equine Hospital + Complete Care, horse owners have access to a wide network of equine practitioners.
“We are able to provide all aspects pertaining to the ICSI process,” says Dr. Melissa Pratt, director and theriogenologist at Equigea. “We do the aspirations here to recover the oocytes, and then we’ll do the injections at our own ISCI lab, so the oocytes do not need to be shipped anywhere, which makes us stand out from other places. And then any resulting embryos we can either cryopreserve those to be transferred at a later date, or we can transfer them fresh into one of our recipient mares.”
As the lead veterinarian, Pratt does the aspirations to collect the oocytes from the donor mares herself and works alongside a technician who came from the human in-vitro fertilization (IVF) world in the laboratory to fertilize and either store or implant the embryos using Avantea’s procedures and technology. While the lab work is done in-house at Peterson Smith, Pratt consults with Avantea, which is based in Italy on all lab decisions.
Photo courtesy of Equigea
Once oocytes are aspirated, they are placed in a maturation media until mature. At that point, the oocytes are injected with sperm. Pratt then checks for embryos beginning at seven days post injection. By day 10, she knows whether an embryo has formed, which mimics the timeline seen in natural breeding. Once an embryo is formed, it can either be implanted into a recipient mare, which can be provided by Equigea, or frozen for preservation. The entire process can be done in-house, eliminating the need for shipping, where delays can affect viability.
“It provides a little bit of continuity and fewer variables,” says Pratt. “So once you start opening yourself up to having to ship oocytes, there’s all kinds of things that can happen. They can get lost with FedEx; they can get lost with airplanes, which then forces a delay in getting them into the lab, getting them in maturation. It’s fewer variables when you’re doing it all in one place, which then makes it easier to ensure the quality is going to be the best it can be, because you have more control.”
The ICSI process was initially used primarily for mares who had trouble conceiving or had trouble maintaining a pregnancy or for stallions with limited semen or poor quality semen, but the advances in technology make it a good option for mare owners who want to limit the amount of time their horse misses from competition. With very little down time needed for the aspiration process, mares bred with Equigea can stay in work and shouldn’t miss any showing, and Pratt has seen an uptick of competing mares over the last two to three years.
“It doesn’t really affect the mare’s day-to-day,” says Pratt. “We can bank all of those embryos that we make, store them in the tank, and then whenever they’re ready to start transferring, we can go ahead and transfer. We don’t need the mare, so it’s essentially the same thing as freezing semen. You can bank it; it can sit in the tank as long as it’s stored correctly. They can store them forever and they can start pulling out the embryos and using them whenever they’re ready, so it’s really convenient.”
Of the different assisted reproductive techniques, ISCI provides the “biggest bang for your buck” to mare owners, according to Pratt. When she aspirates the follicles, each oocyte recovered is a chance for an embryo, while other options result in a single embryo. With ISCI, multiple embryos can be stored and used as desired, meaning a mare can produce several foals from one retrieval.
“We’re getting really good results, and we’re a family vibe here, where we’re just as invested in getting mares pregnant because we are a lot smaller than other places,” says Pratt. “We truly are invested in each horse that we see, and that’s what we put into every case that we’re dealing with is a personalized approach as opposed to just banging through numbers.
