Cooled/Frozen Semen
Articles ( * = members only )

Artificial Insemination: It's Not How Much You Have, It's Where You Put It
When it comes to artificial insemination, the site of deposition might have a big impact on the procedure's outcome. Placing semen directly into the uterine horn containing the ready follicle could allow breeders to use far less ejaculate per mare, maximizing stallion fertility rates, and reducing the likelihood of endometritis, according to Juan Samper, DVM, PhD, Dipl. ACT, of Langley, British Columbia, Canada, who presented his findings on the ... Read full story

Ice Formation Not to Blame for Loss of Viability in Preserved Equine Sperm *
Loss of spermatozoa viability following cryopreservation, historically attributed to the formation of intracellular ice, is now believed to be a result of an osmotic imbalance during thawing. Osmotic imbalances result in the movement of water into cells, causing them to swell and burst. In a recent study co-authored by John Morris, PhD, from Asymptote Ltd., a United Kingdom-based company specializing in controlled solidification, spermatozoa were ... Read full story

Frozen vs. Cooled Semen  *
We are getting ready to breed our mare to a stallion whose semen is only shipped frozen. Does using frozen-thawed semen instead of cooled semen reduce the chances of our mare getting pregnant? Sheri Generally, any time you manipulate semen, the per-cycle pregnancy rate decreases. The rate should be highest for fresh semen, then shipped semen, followed by frozen-thawed semen. This assumes a reproductively healthy mare and stallion. Per-cycle ... Read full story

Breeding Globally--AI Advances  *
Breeding without boundaries; it sounds like science fiction. Yet today we can breed two animals from different time zones, even different continents, through advances in artificial insemination. In this article, we will delve into the present and future of this advancing technology, discussing how it can be used for the convenience of owners and the betterment of breeds. But first, a little history... Artificial insemination (AI) is the collection ... Read full story

International Breeding
I brought two Walking Horse mares to France. I would like to breed to a U.S. stallion and want to know what the success rate might be with shipped frozen or cooled semen. Will I run into importation red tape? Joey Expect LOTS OF RED TAPE. It would be best to deal with frozen semen because of the risk of transport delays. The most expedient way to navigate importation and customs requirements would be to see your local agricultural ... Read full story

AAEP Convention 2004: Sperm Membrane Integrity  *
While a large part of microscopic semen evaluation centers around motility (directional sperm movement) and morphology (sperm structure), some reproductive specialists think there's more to the story. In an attempt to better understand stallion fertility, Steven P. Brinsko, DVM, MS, PhD, Dipl. ACT, associate professor of theriogenology at Texas A&M University, presented the results of research investigating the relationships between sperm membrane ... Read full story

Semen Evaluation  *
Breeding horses today often involves the use of artificial insemination (AI) with fresh, cooled, or frozen semen (except for Thoroughbreds). But whether you are using AI or live cover, the main goal is to get a viable sperm to fertilize a mature, healthy ovum (also known as an oocyte or egg). Therefore, it is important to evaluate and understand the sperm-producing capabilities of a stallion and understanding the quality of his semen. Terry Blanchard, ... Read full story

Advances in Artificial Insemination  *
Artificial insemination (AI) is becoming an increasingly popular method for breeding horses, and with that comes advances in the timing methods used to inseminate mares. "Breeders have embraced the use of transported cooled semen for all the benefits associated with shipping semen to mares as opposed to shipping valuable mares and foals to stallions for live cover or on-farm AI," said Paul R. Loomis, MS, CEO of Select Breeders Services in Colora, ... Read full story

AAEP 2003: Artificial Insemination Made Simple  *
Ed Squires, PhD, an honorary Diplomate in the American College of Theriogenology (reproduction), of Colorado State University, presented a lecture at the 2003 American Association of Equine Practitioners’ convention on a simplified strategy for insemination of mares with frozen semen. Squires said the perception in the industry is that mares must be examined four to six times per day to use frozen semen successfully. He said the reasons for frequent ... Read full story

Evaluating Semen Quality  *
Stallion owners must determine if their stallions have what it takes physically to make a good breeding prospect, including good semen quality, before the start of the breeding season. In his presentation at the sixth annual Equine School at the Alltech Symposium, Peter Sheerin, DVM, Dipl. ACT, a theriogenologist at Rood and Riddle Equine Hospital in Lexington, Ky., asked the audience: “What is good semen quality?” “One definition of good semen ... Read full story

Uterine Lavage Before Insemination Not Harmful to Mare Fertility  *
Uterine lavage can be performed immediately prior to artificial insemination in mares without adversely affecting fertility, according to a recent study completed at the University of Idaho (UI) in Moscow, Idaho. The uterine lavage process is used to clear the uterus of inflammatory fluids that could decrease the viability of semen in mares. Researchers already knew that uterine lavage could be performed as soon as four hours after insemination ... Read full story

AI Made Easy   *
Ed Squires, PhD, an honorary Diplomate in the American College of Theriogenology (reproduction), of Colorado State University, presented a lecture at the 2003 American Association of Equine Practitioners’ convention on a simplified strategy for insemination of mares with frozen semen. Squires said the perception in the industry is that mares must be examined four to six times per day to use frozen semen successfully. He said the reasons for frequent ... Read full story

Effects of Airport Radiation on Shipped Semen   *
As airports across the country and around the world continue to tighten security, there is a growing concern among some researchers that increased radiation levels for screening luggage and shipped parcels have the potential for damaging shipped semen. Terry Blanchard, DVM, MS, Dipl. ACT, of Texas A&M University, says that even before the Sept. 11, 2001, terrorist attacks, the radiation levels for screening luggage and shipped parcels had been ... Read full story

Factors Affecting Fertility with Cooled Semen  *
With the use of cooled shipped semen on the rise, breeders want to maximize the effects of this new technology as best they can. However, there are a variety of factors that can affect fertility with cooled semen, said Dickson Varner, DVM, MS, Dipl. ACT, professor in equine reproduction in the College of Veterinary Medicine at Texas A&M University (TAMU), at his presentation at the Bluegrass Equine Reproduction Symposium. The symposium was sponsored ... Read full story

Foal Sex Selection   *
Sex selection of foals prior to conception is highly desirable for horse breeders. Currently, sperm can be sorted by their X and Y chromosomes, improving odds of sex selection through artificial insemination. Flow cytometry measures DNA in cells and can sort sperm, but it's time-consuming and damages sperm, leading to great losses during the procedure. Freezing sperm destroys many cells, leaving fewer for insemination. Techniques for placing sperm ... Read full story

Finding a Suitable Cooled Semen Facility
I'm considering using shipped cooled semen for my mare. I want to find a reliable farm/facility to take the shipment and breed her. How do I find a qualified facility? What questions do I need to ask about quality? Is there a site or a book to inform me about this? Kandyce Equine practitioners offering ambulatory services can often provide this service on the farm. However, few would argue that fertility can be optimized by taking your mare to a ... Read full story

Modifying Semen Extender  *
Stallion semen is particularly susceptible to freeze-thaw damage, so multi-step procedures are being developed and evaluated to slowly extend and cool the semen prior to freezing it. In addition, the common semen extender INRA82, developed at INRA-Haras Nationaux in Nouzilly, France, is being modified with various additives in an attempt to improve it. A series of experiments was recently conducted in Nouzilly to evaluate the effects of INRA82 with ... Read full story

Scientists Uncover New Way to Assess Ovulation  *
Veterinarians generally assess whether a mare has ovulated and is ready to breed by rectal palpation. However, new research suggests that a mare’s blood plasma sample can tell the veterinarian just as accurately that ovulation has occurred. The Japan Racing Association (JRA)-sponsored study was presented at the 43rd Annual Meeting of Investigation and Research Concerning Racehorses, held Dec. 3, 2001, at the University of Tokyo in Japan. The study ... Read full story

Semen Gains Entry  *
Effective Oct. 20, the United States Department of Agriculture (USDA) Animal Plant Health Inspection Service (APHIS) eliminated importation requirements for equine semen crossing the border from Canada. That decision has the horse industry delighted, and distraught. What is relief for some, easing the logistical headache of cross-border semen shipping, is a nightmare to those who see the potential for introduction of infectious disease. The rule ... Read full story

A Breed Apart: Cooled and Frozen Semen  *
The shipping of cooled and frozen semen has opened the door to a wide variety of breeding opportunities for horse owners, providing, of course, that their breed organization permits artificial insemination (AI) with shipped semen. A mare in New York, for example, can be bred to a stallion which is standing in California and never leave her home farm or come into physical contact with the stallion. The stallion's semen is shipped across country ... Read full story

Freezing Semen  *
The technology that allows us to freeze a stallion's semen for future use has opened up a world of opportunities. Not only does it allow the DNA of a stallion to be available to mare owners around the globe, but it enables a stallion to stand at stud while he continues his performance career. It also means reduced transport costs and less stress for mares (and their foals-at-foot). And with frozen semen, there is no limit to the length of the transport ... Read full story

Consequences  *
Do you want a say-so in what the United States government is doing that concerns horses? I’m talking about the issue of allowing equine semen into this country with even less testing than presently is required. Horse breeders know that semen can carry a lot more than the hopes of the next generation. Viruses, bacteria, and a host of other contaminants happily can travel along with the semen. Cooling and freezing are great ways to prolong the life ... Read full story

Does Frozen Semen Really Work?  *
It has been more than 40 years since Canadian investigators reported the birth of the first foal from the insemination of a mare using frozen stallion semen. Since then, the technology of semen freezing has evolved tremendously. On a yearly basis, thousands of mares are inseminated with frozen semen around the world. Although the technology for freezing stallion semen has improved dramatically, pregnancy rates of mares bred with frozen semen average ... Read full story


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