It is always exciting to see a litter born using frozen semen. We inseminated an Afghan Hound with semen that had been frozen for 23 years and a picture of the outcome is below. How wonderful to have the opportunity to go back that many years into a gene pool that would have been lost!
Clients often wonder why breeders go through all the effort to freeze semen. Here are a few of the positive attributes:
If you feel your dog has the genetic potential to improve your breed, he should have semen frozen while he is young after his health clearances are done. The semen will be available years later to be used by other breeders or by yourself in your own breeding program. You can always destroy the semen if you decide not to use it, but it is better to have it in case something unforeseen happens to him.
Once semen is frozen, it is always available for usage when a bitch comes into season. This is especially important when a lot of stud dogs are busy on the show circuit and not easily accessible for collections when needed.
Frozen semen is the most reliable form of semen when shipping overseas where it may take a bit longer to clear customs and get to its destination. Most of the shipper tanks will hold the semen frozen for up to 3 weeks, whereas chilled semen will not survive that long.
Semen is collected by manual stimulation of the dog. We get a much better sample to freeze when a “teaser” bitch in season is present. We encourage you to talk to your friends with intact bitches and borrow one when she is “prime”, at about 7-10 days into her estrous cycle, to be used as an incentive for your male!
The semen is then examined for motility as well as morphology, which is the quality of the semen as far as percentages of normal and abnormal sperm. We like to have semen that is as least 80% normal sperm to freeze as we will lose some of it during the freezing process. Good quality semen, going into the process, is a MUST if we are going to get good quality frozen semen to inseminate years later.
The semen is then spun in a centrifuge to separate out the semen from any prostatic fluid as we want to only freeze the semen portion of the collection. The semen is then mixed with an extender, which is a solution that contains nutrients, antibiotics, buffers and protectants to help stabilize the sperm cell membranes during cryopreservation. The mixture is then refrigerated to slowly start cooling down the semen.
The chilled semen is then either loaded into straws, which are thin plastic tubes, or made into pellets, which are single drop-sized “dots” made in dry ice and stored in a cryo-vial. Each straw/cryo-vail is labeled for identification with the dog’s name, AKC number, DNA number, date, owner’s name and breed. These are immersed in liquid nitrogen, which is about -320°F and stored until needed.
After freezing, either 1 straw or 1 pellet is then thawed in a water bath at body temperature and the semen is then evaluated under a microscope to see what percentage of good quality semen survived the freezing process. This then allows us to calculate how many pellets or straws will be needed to give us a “breeding unit”, or calculated amount of semen needed to breed 1 bitch.