courtesy of American Association of Equine
Practitioners and Bayer Corporation
Breeding With Transported Semen
Today's breeding technology provides horse owners more options than were
available in the past. Artificial insemination and semen preservation techniques
make it possible to ship stallion semen to mares nearly anywhere in the country.
But success with transported semen will depend on the careful reproductive
management of both stallion and mare.
Why Ship Semen?
Even under the best conditions, transporting horses long distances can be
stressful and costly. Mares with Foals are of special concern, since foals are
particularly vulnerable to disease and injury when exposed to new horses and
environments. Older or injured mares, or those requiring special care, may also
benefit from staying closer to home during breeding season. The ability to ship
cooled semen makes it possible for breeders to arrange matings that might
otherwise be impractical due to distance, economics or health.
Many - but not all - horse are good candidates for the use of cooled
transported semen. Both mares and stallions should be in excellent reproductive
health, since fertility problems tend to be compounded when transported semen is
added to the breeding equation.
With shipped semen, there is generally only one opportunity per cycle to
breed a mare. Problem breeders may fare better at the stud farm, where they can
be monitored and serviced at regular intervals throughout their heat cycles.
Also be aware that not every stallion's semen cools or ships well. Therefore,
it is critical for a stallion's sperm viability to be checked after a dose has
been extended and cooled for 24 to 36 hours. This is generally the interval
between collection and the time the transported semen is placed in the mare.
If you are planning to raise a registered foal, be sure to check the
association's rules regarding semen transport in advance and follow them. While
registry acceptances are growing, no every breed registry permits the use of
Breeding with cooled transported semen is more management-intensive than with
on-site matings. Timing is critical. For the greatest chance of pregnancy, a
mare must be bred from 12-24 hours before ovulation to up to six hours after
ovulation. From a practical standpoint, however, once the mare has ovulated, it
may be difficult to determine whether you are still within an acceptable time
from e for fertility. Also, remember cooled stallion semen only has a shelf life
of 24-48 hours.
Prior to breeding season, a mare should have a full reproductive examination.
A uterine biopsy and culture may be indicated to get a clearer picture of the
mare's overall reproductive health. During breeding season, the mare should be
kept where she can be teased by a stallion on a regular basis in order to detect
the onset of estrus reliably.
Once the mare comes into heat, your equine practitioner will need to predict
the onset of ovulation accurately - allowing time for the semen shipment to
arrive. The veterinarian will monitor the mare daily or every other day via
rectal palpation and ultrasound throughout her heat cycle to determine the
appropriate time to breed her.
The stallion should also be evaluated for fertility prior to the breeding
season. Semen should be tested by extending, cooling and storing it in the same
way it will be handled for shipping. Commercial extenders have different
formulations. The stallion manager or veterinarian may want to experiment to see
which extenders promote the greatest viability. Proper handling is also
important. Here are some considerations:
An insemination dose of cooled semen requires 1 billion progressively motile
sperm cells, twice the number used in fresh insemination doses. Following
storage and transport, 500 million progressively motile sperm cells would be
considered a minimum insemination dose.
Veterinarians and stallion managers should have the equipment to determine
sperm concentrations and motility accurately. Doses should not be estimated.
Semen extenders should contain antibiotics to help reduce bacterial
contamination and the spread of disease.
A high quality shipping container is essential to semen viability; directions
should be followed exactly.
Due to variability between individual characteristics of each stallion's
semen, the procedures for extending, shipping, handling and insemination may
vary. Directions from the attending veterinarian or stallion manager should be
Any semen which remains after the mare has been bred should be checked for
Semen not used within 48 hours should be discarded even though it may still
appear to be viable.
Communication and Cooperation
Good communication between stallion and mare managers is essential.
Coordinating semen shipments will take planning and cooperation. Most stallion
managers plan collection schedules so as not to overtax a stallion's fertility
or reproductive performance. Collections made 3-4 times per week will
accommodate most cooled transported semen requirements without negatively
affecting fertility, while allowing breeders to meet on-site demands as well.
The mare should be on a regular teasing and examination schedule to reliably
ascertain the proper time to breed. This will allow planning and timely shipment
of cooled semen. Many overnight shipping services provide prompt, reliable
deliveries and can reduce the need for last-minute trip to the airport.
Transporting seen may have some cost-saving benefits. However, they can be
offset by increased management costs. Additional costs may include:
Special handling and shipping charges
Board, mare care, teasing and management at a breeding facility or clinic.
Veterinary examinations, palpation's, ultra-sound and artificial insemination
Pregnancy rates with transported semen are somewhat lower than with
on-the-farm breeding. This means it may take more than once cycle to get a mare
in foal. The mare owner absorbs the cost of additional semen shipments,
veterinary procedures and mare care.
A Team Effort
Breeding with cooled transported semen is a team effort requiring the
expertise of qualified professionals. The goal is to produce a healthy foal in
the most efficient, effective way. To prevent disappointment, undue expense and
loss of valuable time, you must do your part to ensure success.
credentials and references of the breeders
and professionals with whom you plan
to do business.
stallion and mare management facilities
and an equine reproductive specialist
whom you trust.
a good line of communication between
facilities if possible.
breeding contract carefully.
the associations with which you are
affiliated for their guidelines.
These forms and instructions are available for you to download. You may
retrieve the documents and view them on your screen. You may also print the
forms, fill them out and mail them to the ApHC for processing.
The ApHC forms on this page are in a Portable Document Format
(PDF), which is
a universal electronic file format.
Adobe Acrobat Reader enables DOS, Macintosh, UNIX and Windows users to view,
navigate and print any PDF files they receive. Click here to download a free
copy of the Acrobat Reader.