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Equine Embryo Transfer
Transcript of Equine Embryo Transfer
Equine Embryo Transfer
Embryo transfer is altering the way that horses reproduce. This is a concern for many due to the sensitive nature of life. Embryo transfer may result in the termination of an embryo, which can be controversial. The genetics may be altered in ways that would not occur from natural breeding. There are also welfare issues that need to be addressed concerning embryo transfer
Horses are not capable of super ovulation (ability to produce multiple eggs through hormone treatment) like cattle are which makes the success rate much lower than seen in other livestock species.
The success rate for each estrus cycle is 25-50%, and the estrus cycle in a horse is 21 days long. The low success rate increases the likelihood that more procedures will take place and put added stress on the horses involved
Embryo transfer has changed equine genetics in several ways:
Competitive mares are now able to reproduce and are not being taken out of competition, before embryo transfer these mares would only be in competition and would reproduce after they retired or less athletic mares were used. The foals produced from embryo transfer are able to be more athletic.
Better genetics helps to increase the value and demand of foals that are produced through embryo transfer.
In some cases a narrower range of genes are being used because popular bloodlines are more widely available.
The ability to select for more athletic mares that are not carriers of genetic disorders has helped to prevent breeding the lines that do carry genetic disorders.
Stress and Welfare
The process of embryo transfer requires a high amount of veterinary interaction and requires several recipient mares. This process puts a large amount of stress on the horses involved. Animal welfare groups aim to put as little stress on the animal as possible and embryo transfer can be viewed as an unnecessary procedure that increases the stress in multiple animals. Live cover or artifical insemination, without the removal and implantation of the embryo as well as the mandatory synchronization would minimize the stress and comply with animal welfare standards.
Equine Embryo Transfer is the process of impregnating one horse and then removing the embryo and implanting it into a recipient mare that will carry it to term. Several mares must be used to synchronize the estrus cycle with the donor and the closest will be chosen as the recipient.
Breed Organization Issues
Breed organizations that allow embryo transfer (such as the American Quarter Horse Association) are experiencing the dilemma of whether to allow registration of multiple foals from one mare. A mare that gives birth to her own foal can only produce one per year while embryo transfer allows multiple foals from one mare to be born each year and has caused problems with a rule that previously only allowed one foal per dam to be registered. Other Breed organizations may not accept embryo transfer foals, one example of this is the Jockey Club which thoroughbreds are registered through for racing.
A Quarter Horse donor mare with three foals produced by embryo transfer
various aspects of the embryo transfer process
Embryo transfer is a process that many view as disrupting the natural order of life. It may result in a termination of an embryo, providing changes to a bloodline that may not of otherwise occurred, and may present animal welfare and rights controversy. This process although controversial allows many mares to reproduce that otherwise cannot due to biological or competitive reasons.
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