Semen Freezing Information

Semen Cryopreservation and Storage

At Veterinary Hospital Hospital at the Lake, one of our most unique services is freezing and storing canine semen. If you set up a consultation for semen cryopreservation, we will collect a sample of semen from your dog and do a complete semen evaluation, including analysis of sperm count, sperm motility, and sperm morphology. Based on this analysis, we may or may not recommend moving forward with freezing your dog’s semen.

How does semen freezing work?

Once the semen is collected, evaluated, and found to be of sufficient quality to freeze, we will process it with a special extender that contains nutrients and cryoprotectants that will help the sperm cells survive the freezing and thawing process. The extended semen will be placed in ½ cc straws that are individually labeled with your dog’s name and other identifying information. These straws will be chilled in a controlled manner and then frozen in liquid nitrogen. Once the semen is frozen, we will thaw a partial “thaw straw” for evaluation – this is what determines the post-thaw motility and subsequent breeding dose.

What is a breeding dose/unit of frozen semen?

A breeding dose of frozen semen is the minimum number of motile sperm that are likely to produce pregnancy when used for insemination. The definition of a breeding dose in the dog is something that is constantly changing. We used to say that a breeding dose was 100 million motile sperm POST-THAW, however with recent advances that definition has been changing. The current thought is that 100 million motile sperm may be an adequate breeding dose for a small breed dog, however, larger dogs likely should be inseminated with larger breeding doses. When you have semen frozen on your dog, you should inquire about how they are defining a breeding dose.

Why freeze semen on your dog?

By freezing canine semen, we can preserve your dog’s fertility for an unlimited period of time, as long as that semen is frozen and stored properly. Dogs don’t live forever, and their reproductive is even shorter, so by freezing your dog’s semen while he is young and healthy, you can preserve his future fertility for a lifetime or beyond.

When to freeze your dog’s semen?

We recommend freezing your dog’s semen when they are young and in good health. Most dogs reach peak fertility at around 2 years of age, and fertility can start declining between 4-5 years in some dogs, so it’s always better to have semen frozen when the dog is young as opposed to waiting until he is in his older years. We recommend being proactive rather than reactive by freezing semen when your dog is still young and fertile, rather than risking loss of fertility/inability to collect and freeze a quality sample later in life.

How is frozen semen stored and transported?

Frozen semen is stored in specialized liquid nitrogen tanks that, if maintained appropriately, keep the semen viable indefinitely. Semen can also be shipped in a special container called a “dry shipper” that holds liquid nitrogen vapors for up to 2 weeks to keep the frozen semen at the appropriate temperature as it’s transported to other parts of the country, or even internationally. We offer long-term semen storage here at VHL and we are also a Zoetis Semen Freeze Center, so we can transfer some or all of your semen there for storage if desired, and they provide discounted shipping rates from their Semen Bank to our facility and other Zoetis Freeze Centers.

How is frozen semen used?

While we can utilize semen cryopreservation techniques to indefinitely preserve a dog’s fertility, the viability of thawed frozen semen is less than a fresh or chilled semen sample would be. Pregnancy rates with frozen semen range between 50-70%, so when you are going through the cryopreservation process with your stud dog, I recommend storing twice as many breeding units as litters you think you might want in the future. Because frozen semen is used in small breeding doses and has a shorter lifespan than fresh/chilled semen, it must be inseminated directly in the uterus, either via surgical insemination or transcervical endoscopic insemination (TCI), which involves the use of a rigid endoscope to visualize the cervix, put a catheter through the cervix, and inject the semen directly into the uterus.