What is Bovine Embryo Transfer?

Embryo Transfer is a progressive reproductive technique that’s purpose is to maximize the genetic impact that a high- ranking animal has on your herd, and beyond, by vastly increasing the number of offspring produced by that female.

How many embryos can a donor produce?

An embryo collection can potentially be performed on a donor cow or heifer every 28 days. The average number of transferable embryos per flush is between five and six. However, results can greatly vary with some flushes resulting in no viable embryos and other flushes yielding more than thirty transferable embryos.

How do you set up a donor for ET?

Conventional embryo transfer involves specific timed hormonal treatment using follicle stimulating hormone, FSH, of a donor cow or heifer to promote the ovulation of numerous follicles. This process is known as superovulation. RVS will provide you with a tailored schedule detailing every step you need to take to successfully prepare your donor for her flush date.

At signs of estrus (or standing heat), the donor/s is then bred using artificial insemination. The eggs produced during ovulation are now fertilized and are left to maturate in the donor’s reproductive tract for several days.

How are the embryos retrieved from the donor?

On approximately day seven after insemination, the embryos are non-surgically collected, or “flushed”, from the donor’s uterus via intrauterine catheterization using a sterile flush solution. The embryos are safely procured using a filtration system and immediately brought to a laboratory for inspection and manipulation.

What happens to the embryos once they are collected?

Once the embryos have been inspected under a microscope and deemed viable, they then may either be transferred directly into recipients (who serve as surrogates) or the fresh embryos are frozen to be thawed and transferred into synced recipients at a later date.

Note that recipients must be synchronized, via natural cycle detection or artificial hormonal treatment, and approximately seven days post estrus in order to achieve a viable transfer resulting in pregnancy.

If/when the embryos are frozen, they are safely stored in liquid nitrogen storage tanks until a client is ready to transfer them into viable recipient females. Clients may store their embryos in their personal tank on- farm or RVS is happy to safely secure them at its highly monitored storage facility.

Can frozen embryos be shipped internationally?

As required by the International Embryo Transfer Society, all frozen embryos are to be marked and handled with a specific standard to which RVS is accustom. This enables us to ship your embryos to other livestock producers within the United States. We can export them to international producers, as well. Rolleston Veterinary Services is also certified by the American Embryo Transfer Association.