Welcome to the world little Jamie - Veronica (standing) and Kylie (kneeling)
On January 12th 2014, Hawkesbury Equine Veterinary Clinic welcomed to the world one of the first foals in the Hawkesbury resulting from embryo vitrification.
Veronica Hazelton sent us this gorgeous photo of little ‘Jamie’ and filled us in on how this little filly came to be ...
On January 12th 2014, Hawkesbury Equine Veterinary Clinic welcomed to the world one of the first foals in the Hawkesbury resulting from embryo vitrification. The new filly named ‘Jamie’ was conceived using chilled artificial insemination in January 2013. The filly’s dam Lady (Statford Lady Aviatorix) is a lovely tall elegant mare with superb paces and a wonderful nature who was bred to event. Sadly she suffered a paddock injury shortly after being broken in and was retired for breeding. Jamie's is by the warmblood Redgum James 007, so the outcome is a little filly that is 70% TB with great warmblood type movement.
Lady was ‘flushed’ 6.5 days after ovulation and the embryo was recovered and cleaned. At this stage, the embryo, which was to become ‘Jamie’ was only 150 microns in size, which is smaller than can be seen with the naked-eye. The embryo was then vitrified (frozen) and stored in a liquid nitrogen tank. Because this was a trial, the embryo was transferred two weeks later into a recipient mare named ‘Bossy’. After 348 days gestation, Bossy gave birth to a stunning healthy filly named ‘Jamie’.
A few weeks on we are happy to report that Jamie has 3 amazing paces with natural spring and suspension ...
and rather attractive to boot!
Kylie Hardwicke BVSc BIO, who has been very much involved with this new foal, explains what embryo vitrification is all about …
What is embryo vitrification?
Embryo vitrification is a new and arising technique that now offers many more options to owner’s wishing to get the most out of their mare’s genetics. Embryo vitrification is a process where a 6 to 6.5 day embryo is frozen by a rapid freeze technique which leaves the embryo in a “glass like” state. These “frozen” embryos are then stored in a liquid nitrogen tank until the owner would like to transfer that embryo into a recipient mare.
Why would you freeze an embryo?
There are several situations in which embryo vitrification may be warranted and beneficial to a breeder. Embryo vitrification is the only available option to preserve a mare’s genetics. A donor mare can have several embryos vitrified for “safe keeping” should the mare be sold, become infertile or pass away. Performance mares that are in training during the breeding season can have their embryos vitrified during the autumn/winter months and have them implanted in September / October. Or finally the mare owner may not have the time or money to transfer and raise a foal at the current time, but can keep embryo/s frozen until the circumstances are right.
What is the process?
The process is similar to routine embryo transfer except that the embryo is flushed from the donor mare earlier than with fresh transfers. This means that the donor mare is bred via natural, chilled or frozen semen and the embryo is flushed from her uterus at 6 to 6.5 days post ovulation. The timing of ovulation is important as flushing a mare too early will not recover an embryo as it may still be within her fallopian tubes and flushing the mare too late will recover an embryo that is too large. Embryo’s that are too large (>6.5 days or 250um) have been shown to not survive the freezing process.
Embryos recovered are then washed and graded. Embryo/s of the appropriate size and grade then undergo a 4 step process using different concentrations of cryoprotectants and substrates before loading them into a 0.25ml straw and frozen in liquid nitrogen. Finally the embryos are placed into storage tanks to use either the next breeding season, or 5, or 50 years later.
When it comes to thawing the embryo, an appropriate healthy young and reproductively sound recipient mare is chosen and her breeding cycle is monitored. 5 days after the recipient ovulates, the embryo is thawed and transferred directly into that mare’s uterus using a trans-cervical approach. The recipient is treated with progesterone, antiinflammatories and sometimes antibiotics to help her keep the pregnancy.
Having the ability to preserve valuable genetics is important to the equine industry. That is why “vitrification” is now available at Hawkesbury Equine Veterinary Centre. The pregnancy rates reported from vitrified embryos have been 70-75% per embryo transferred after utilizing the 4 step vitrification method.
Kylie Hardwicke graduated from Sydney University in 2009 with merit. Her final year rotations included time at Kentucky Equine Veterinary Clinic who have a successful embryo transfer program and the New Bolton Centre in Pennsylvania for their large animal Neonatal Intensive Care Centre.
In 2010 Kylie began work at Hawkesbury Equine Veterinary Clinic Her main interests are reproduction and intensive care medicine including neonatal foal care. In 2012 she visited Royal South West Vista in Oklahoma USA. RSWV perform up to 1,500 embryo transfers per year and a large scale embryo vitrification program. The knowledge gained from the vets at RSWV has helped Hawkesbury Equine veterinary Clinic improve their embryo transfer success rate up to 90% as well as initiating an embryo vitrification program.
