Written by: Sherri L. Barclay of Barclays Arabians
Livestock cloning company ViaGen, Inc. has partnered with equine marketing firm
Encore Genetics to bring this fantasy to life with the first commercial horse
cloning operation in the country. On March 30, 2006, these two companies announced
the news of the birth of two famous horse clones as well as news of yet other
pregnancies.
Royal Blue Boon is a legendary cutting horse registered with the American Quarter
Horse Association. She is now a part of history for being the first mare to be
commercially cloned here in the US. On February 19, 2006, the foal, Royal Blue
Boon Too, was born to a recipient mare in Purcell, Okla. On Royal Vista Southwest
Farms. The foal was born with no complications and continues to thrive on the
farm where she was born.
Not soon after, a clone of the mare Tap O Lena was born on the same farm arriving
on March 9, 2006. Nine additional clones of other celebrated horses are to be
born this year alone. There are still many other ViaGen/Encore mares due in the
year 2007. These two companies have also gene banked more than 75 additional champion
horses from multiple breeds and disciplines. Due to some client confidentiality
agreement, names of these horses could not be released.
Dr. Jim Bailey, DVM and manager of Royal Vista Southwest oversaw the entire cloning
process. "From the time I transferred the embryo into the recipient mare,
these pregnancies were normal in every way and the births followed suit. The resulting
foals were born normally and immediately stood to nurse. They bonded well with
the recipient mares and continue to grow and play in the sun."
Unlike the movie Jurassic Park, in order to make a clone of a horse the technique
is a bit different as well as fairly simple. First, there is a biopsy of tissue
taken from the horse to be reproduced. Once ViaGen's lab receives the sample,
cells are grown in a culture. Then a process called Nuclear Transfer takes place.
This is where DNA from the donors cells are transferred into enucleated oocytes
(eggs from which the genetic material has been removed). The embryos are then
grown in an incubator for several days before being transferred to a recipient
mare. This process is the same as with traditional embryo transfer. Finally, once
the mares reach the normal gestation period. The cloned foals are born.
Still a bit confused? Let's look a bit deeper into the cloning process. Livestock
cloning is the most recent evolution of selective breeding in animal husbandry,
which dates back to the dawn of time. Many of our readers may not know this however,
Arab sheiks first used artificial insemination in horses as early as the 14th
century. Techniques such as embryo transfer, in virto fertilization, embryo splitting
and blastomere transfer have become common place in just the last fifty years.
These processes provide farmers and ranchers powerful tools for breeding their
best animals. The cloning process also accelerates the birth of the best possible
stock by allowing horse breeders to be certain of genetic make-up of a particular
animal.
Clones are not genetically modified organisms or GMO's as some people may believe.
Cloning is considered quite simply to be assisted reproduction. Clones are basically
identical twins separated in time. These twins are genetically identical to its
single parent and is developed from a single donated cell.
While cloned animals are genetically identical that is where the similarities
may stop. For instance, during fetal development the cells that produce pigment
called melanocytes, migrate around the fetus. The final location of these cells
is not controlled by genetics and can be affected by the uterine environment.
Because of this the color or pattern of a clone may be slightly different from
that of the original. In scientific terms, their genotype - the clones genetic
makeup as opposed to its physical characteristics. Cloning cannot control the
clones phenotype - or the physical expression of a trait, like the placement of
any of the clones particular markings. So, if you are looking to create an identical
twin of your favorite horse it may not happen. The clones markings may be slightly
different then the donor.
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Clones also have the exact same potential as the cell donor or original. You must
consider however that these clones are brought up in a different environment at
a different time. Essentially; nutrition, socialization, exposure to foreign pathogens,
etc. can affect behavior and the ability to perform. Clones may therefore be different
from each other and from the original cell donor. This means that just because
your horse acts exactly how you want it to, your horse's clone being exposed to
a different environment, may not act the same or do well in the same discipline
as the original.
Cloning does have other challenges. Higher rates of fetal and neonatal issues
were observed with assisted breeding techniques. This includes virto fertilization
and embryo transfer. It has also been noted with cloning.
At this time there are no equine registries that will allow cloned animals to
be registered. They are still considering it as an option however to date none
of the registries have opened up to cloning. The Jockey Club is considered by
some to be the purest of all breeding institutions. They believe that both the
short term and long term health of the Thoroughbred breed is best served without
the use of many current breeding practices. These practices include artificial
insemination, embryo transfer and cloning.
Next month we will continue to look at this controversial process, get reactions
about cloning and explain how you can gene bank your own horse.