| Breeding - Horses - Frozen Semen Expert Paul Loomis Questions (For answers, scroll down or click on question) What kind of results can I expect with frozen semen? Are all stallions good candidates for frozen semen? Questions and Answers {For Mare Owners} Q. What kind of results can I expect with frozen semen? A. Although some stallions have similar results
with frozen and fresh semen, AI with frozen semen, from most stallions, results in
slightly lower fertility per cycle than similar inseminations with unfrozen semen. When
stallions are selected for AI programs based on post-thaw semen quality, and mare
management is controlled, per cycle pregnancy rates of 40-50% can be expected on average.
This compares to 50-60% for cooled semen and 60-70% for immediately inseminated fresh
semen. Q. How do I know if my veterinarian is qualified to perform inseminations with frozen semen? A. The actual process of thawing and inseminating
frozen semen is quite simple. One must follow specific thawing instructions precisely in
order to obtain maximum post-thaw survival. This will require careful attention to detail
and properly temperature controlled water bath. However, the most important attribute to
look for in selecting a veterinarian with is extensive experience in equine reproduction,
broodmare management, and artificial insemination. To obtain the best results you mare
will need to be examined regularly during her heat cycle, and sometimes twice per day
palpations are required. The use of ultrasonography is also helpful to monitor follicular
development, and accurately predict the time of ovulation. Technical experience and a
commitment and interest in properly managing the inseminations is crucial. Q. Do I or my vet need special tanks to hold the frozen semen? A. No. The shipping tanks are specially designed
cryogenic vessels which maintain the frozen semen at –197 degrees centigrade for at
least two weeks. This allows shipment of the semen to your vet well in advance of the
anticipated insemination date avoiding the last minute "mad rush" to schedule
semen shipments that are associated with cooled transported semen breeding. Also, if the
mare fails to ovulate when predicted, no further shipments are required. There are
sufficient doses of frozen semen in the tank to inseminate the mare again as needed. Q: Could you give me instructions on the proper thawing of frozen semen? A: "Proper" thawing of frozen semen depends upon the package size and type and the freezing procedure used. Equine semen is most commonly frozen in small (0.25 or 0.5 ml) or large (2.5-5.0 ml) plastic straws. Semen should always be shipped with detailed instructions on thawing and handling recommended by the laboratory processing the semen. When available, those instructions should be followed exactly. Generally, we recommend that 0.5 ml straws be thawed in a 37°C water bath for 20-30 seconds. Larger 4.0 and 5.0 ml straws should be thawed in a 50°C water bath for exactly 45 seconds. For a copy of our detailed thawing, handling, and insemination protocols, please contact Select Breeders Service, Inc. at 410-658-3328 or SELBREED@aol.com. {for Stallion Owners} Q. Are all stallions good candidates for frozen semen? A. Not all stallions can be frozen successfully.
Based on studies conducted in Europe and experience of SBS, approximately 30% of all
stallions produce sperm which are unable to withstand the stresses of freezing and thawing
using current technology. Q. How many doses of frozen semen will my stallion produce from a collection? A. The average stallion provides sufficient sperm
on an every other day collection schedule to produce 12-15 doses of frozen semen.
Depending on sperm production of the individual this number may vary from 2-40 doses per
collection. Typically 2-3 doses are used per estrous cycle, therefore each collection
provides enough frozen semen to inseminate through 5-6 cycles. Q. How long will the frozen semen be good for? A. If stored properly frozen semen can maintain
viability for many years. Frozen semen is stored immersed in liquid nitrogen at –197
degrees C (-320 degrees F). At this temperature, metabolism is virtually halted. No one
knows the ultimate lifespan of properly stored frozen equine semen. However, SBS has
achieved pregnancies with semen frozen for more than 8 years. Q. Why is frozen semen such a good alternative to a transported cooled semen program? A. Our distribution program is designed to relieve
the stallion owner of many of the burdens associated with managing a transported semen
breeding program. Once you have booked the mares, our experienced professional staff
handles all the details of the shipments and breedings.
Q: How old must a stallion be before collection of semen is possible? I want to geld my colt but because of his great bloodlines and proven halter performance, I would like to freeze some semen. A: The decision is between 2 and
3 years of age. If the stallion can be reliably collected at two and semen
quality is good, you can freeze semen from a two year old stallion. The
later in the two year old year, the better. A stallion's testicles will
continue to grow until age 5 or 6. A two year old may not produce enough
sperm to make freezing an economically feasible process, therefore, I
would wait until 3.
Q: We are setting up an isolation facility for shipping frozen semen to Denmark. Do you have suggestions for best labs for CEM and EVA testing? Do you have schedules set up for testing on frozen semen? A: We send our CEM and EVA samples to Cornell University. EVA semen samples go to the University of Kentucky. Many state labs can perform the testing as well. Denmark is a member state of the European Union. I suggest you call the USDA at 301-734-8590 to get a copy of the complete requirements for health testing of stallions for export of semen to Denmark. Briefly, the health certificate requires among other things, negative tests for EVA and EIA on blood taken at least 14 days after the last collection for export. The CEM cultures must include two sets (prepuce, urethra, urethral diverticulum, presperm) taken 7 days apart at least 14 days after the last collection for export. All testing must be completed during the 30 day holding period after the last collection for export. Regulations can change so SBS
strongly suggests contacting the USDA for the most current version prior
to any semen freezing for export. SBS operates an annual quarantine for
semen freezing at it's Maryland facility from October - January. For more
information, please contact us toll-free at 877-658-3328 or via email at SELBREED@aol.com.
You can also visit our web site at www.equerry.com/sbs.
Q: Where can I take classes and learn to A.I. in the state of Missouri? A: I suggest you contact the College
of Veterinary Medicine at the University of Missouri Equine Hospital, Ph:
573-882-3513 or www.hsc.missouri.edu/vetmed.
Q: Knowing that to collect and freeze semen, the stallion must be taken to the veterinary hospital - Can we send the chilled semen to the hospital to be frozen rather than hauling the stallion? A: This is not advisable because
the reduction in sperm viability during cooling and transport is partly
due to exposure to seminal plasma. When we process semen for freezing,
seminal plasma is removed by centrifugation prior to addition of freezing
extender. There has been some success freezing semen that has been cooled
following centrifugation and resuspension in non-glycerolated freezing
media. The glycerol is added when the sample arrives and the extended
semen is packaged and frozen. Post-thaw quality of semen frozen using this
technique is generally much lower than immediately frozen sperm.
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