• • 
• Tweet

  

The evolution of the polo pony

From embryo transfers to clones

An article by Dr. Julio G. Oriol DVM, MSc, PhD

By Julio G. Oriol DVM, MSc, PhD

At the end of the 1980’s, the first polo ponies were born via embryo transfer (ET) in Argentina. This method of assisted reproduction was promoted in Argentina by Martin Reynal, who was successful polo pony breeder and previous president of the Argentine Association of Polo (AAP).  At this time, I visited Argentina from Canada with the idea of organising the 3rd International Symposium of Equine Embryo Transfer, but this met with some resistance from breeders, especially the thoroughbred breeders. However, thanks to support from the Argentine Veterinary Equine Association and a group of veterinarians interested in equine reproduction, the conference went ahead.

The cover of the book of the resulting conference was a scene from the Argentine Open, a decision made jointly with Professor W.R. "Twink" Allen, the global pioneer of ET.  We both believed that polo ponies would be the biggest beneficiaries of this method of reproductive assisted technology. The conference also gave the founding knowledge to many Argentine veterinarians who had just started using assisted reproductive techniques.

Now, 20 years after that conference, I have no doubt that we didn’t make a mistake, and all the breeders understand the huge positive impact that ET had in the genetic selection of polo ponies. There is a presumption that the genes that give ability for playing polo to the ponies are largely inherited. The empirical proof that the best mares produce the best offspring is easy to see in the catalogues at the horse sales. With time, the ET process has become more efficient, the use of frozen semen has increased, the success rate of frozen embryos, and foetal sexing and semen sexing have also all increased. As a result, all the breeding population has improved, and polo ponies seem to be better than in the 1980's.

When in 2003 the first equine clones were born, people began to look to polo ponies as the ideal horse to clone, partly because the polo pony breed associations are so open to assisted reproduction techniques, and partly because as previously mentioned, the high inheritability of the polo playing genes.

The first commercial clones were produced by Dr. Eric Palmer’s Cryozootech, based in France. There, the greatest implications were for the world of Showjumping. The firm had tremendous problems in registering the cloned horses, under a cloud of controversy. It was not until July 2012 that the Federation Equestrian International (FEI) authorized the competing of clones and their offspring. Still, many breeders maintain that horses should be bred in fields, not in labs. 

Back to polo: Polo breeders have always looked favourably on the possibility of cloning. It is likely to be the only breed association that never opposed it. For example the AQHA (American Quarter Horse Association) which has now allowed the process, had at one stage opposition of 86% in a poll done by the association. Bit by bit the various associations are allowing the registration of clones, with the exception of the thoroughbred breeders, where every method of assisted reproduction is banned, even the simplest of all, artificial insemination.

However, cloning process is as yet extremely inefficient. The clone begins with the oocyte. These form the chamber in which the collected cells from the horse to be clone are placed. The oocytes are collected from ovaries which are obtained at the abattoirs.  It takes around 500 equine ovaries to clone just one horse. This requires a lot of slaughterhouse material for the process to work. United States of America has banned the slaughter of horses in abattoirs, which by default put Argentina on the map, as around 200,000 horses are slaughtered in the country every year. Therefore, a lot of material can be obtained in Argentina to make a lot of clones.  Once the embryo has been created in the lab it is transferred to the mare, again, Argentina has many ET centers with good numbers of very well synchronized recipient mares.

In 2010, in association with Crestview Genetics in the USA, was the first to clone a polo pony. The clones were created in the USA and then sent to Argentina once they were born, to be raised and backed.

Also in 2010, a group of Argentine scientists led by Dr. Daniel Salamone of the University of Buenos Aires produced the first non-commercial equine clone in South America.  The technique used was very novel, and improved the efficiency of the cloning process. This led to his recognition by the prestigious magazine Biology of Reproduction. The editors put the story on the cover, an honour that is on par with winning the Open. This work is also another improvement for the Argentine horse industry.  The work was partially supported by the Sidus Group, an Argentine company who was also produced transgenic cows. At this moment there are three groups working on the cloning process.  

In a few years, we will see the boost to polo that the clones of the top ponies will bring. With all certainty the Argentine Polo Pony will continue to be the leader on the international stage thanks to the players and the support of a group of breeders, breakers and vets that have made the breeding of polo ponies an art form. Maybe science cannot beat art, but it can certainly lend a helping hand.

By Julio G. Oriol DVM, MSc, PhD
Equine Reproduction Specialist.
e-mail: juliogoriol@gmail.com

Read the complete article in the next issue of PQ International