FRIESIAN BREEDING

Frozen Semen and Artificial Insemination

Let's face it, if we're going to venture into breeding our Friesian Mares, then Artificial Insemination is, in most cases, our only option. The option of a live cover breeding is less available. Our mares would need to be transported a very long distance, unless we happen to be lucky enough to live near by a breeding stallion that just happens to be a good genetic match for our mare, and the stallion just happens to offer live cover. So, then we must use shipped semen, either fresh chilled or frozen.

 The Following information is comprised of details taken from an article written by Jonathan F. Pycock, BvetMed, PhD, DESM, MRCVS, and RCVS Specialist in Equine Reproduction.

A successful AI depends upon the following components, for the MARE:

A satisfactory Breeding Soundness examination; the induction of an ovulatory estrus; the accurate prediction of ovulation; correct timing of insemination relative to ovulation; appropriate storage, thawing, and handling of semen; correct insemination technique; post insemination examination and treatments as required; and correct pregnancy diagnosis 14 to 16 days after insemination.

 For a typical set of circumstances, a reasonably fertile mare and good quality semen, one can expect pregnancy rates of 35% to 50% per cycle with frozen semen.  The OVERALL pregnancy rates, at the end of the season, including chilled semen inseminations, vary between 50% and 90%, with an average of about 75%, but after the few mares which lose their pregnancies, the resulting live foal rate ends up around 65%.

With frozen semen, there is evidence that some semen might not remain viable as long as 24 hours following insemination, so insemination closer to ovulation is preferable.  The regime most commonly used with frozen semen is to examine the mare every 6 hours as ovulation approaches.  Insemination should be just before ovulation is anticipated.  If semen supplies are limited, insemination can be withheld until ovulation is detected.  This system ensures the use of a single insemination dose at a maximum of 6 hours after ovulation.  In the experience of Dr. Pycock, pregnancy rates do not begin to decline with frozen semen as long as insemination is within 6 hours following insemination.  Ideally, one would prefer to inseminate the mare in the eight-hour period before ovulation.

 To supplement this information, I would like to add an observation noted by a reputable Friesian Horse Breeder in the Netherlands, pertaining to the insemination of frozen semen in Friesian Mares.  This is an observation as a result of extensive experience with AI and the Friesian Horse, though, is NOT a guarantee for a successful insemination.

 It is suggested that, “the Friesian Mare should be inseminated as soon as possible after the ovulation has occurred and the follicle is empty. For example, if at 1pm the follicle is at 5.3 cm, then, at 3pm the follicle is at 3.9 cm, it is time to inseminate!”  Inseminating the mare prior to ovulation is often times less successful, and potentially a waste of valuable semen.

 All straws for the single insemination dose should be thawed for 40 seconds in water that is EXACTLY 100.4 degrees Fahrenheit.

(38 degrees CELCIUS)  NOT warmer! 

Do NOT use Extender!!!!

 Pre-warmed instruments (catheter and syringe) should be used for the insemination.

 For questions and website comments, please email Webmaster. sherri@kasteelfriesians.com

07/30/2009