Insemination is similar for fresh and chilled semen but is slightly different for frozen semen. This is due to the life span of the semen once processed. Frozen semen only lives for a few hours after thawing and insemination. Chilled semen lives for about 5 days in the bitch and fresh semen lives for about 6 days. Since frozen semen has such a short life span, an egg ready to be fertilized must be present at the time of insemination for fertilization to occur.
Once prepared, the semen can be deposited either in the vagina just in front of the cervix or just inside the uterus. Samples deposited just in front of the cervix result in the best success.
Placement of the semen into the proper area of the reproductive tract requires some specialized equipment. Long pipettes are recommended. For small and medium sized dogs, commercially made canine insemination pipettes are available. For large breed dogs, these pipettes are too short, so modified pipettes used in cattle are frequently used. Some people choose balloon catheters but the pipette is most commonly used.
To begin the insemination process, the male should not be around the female. Hold the bitch in a standing position. Draw the appropriate amount of semen into a sterile syringe and attach this to the appropriate pipette. The pipette is then guided into the upper vagina by a gloved, lubricated finger inserted into the vaginal canal. Once positioned, the semen is deposited. The syringe is then filled with air, which is used to inject the remaining semen that remained in the pipette after the initial push of the syringe. The pipette is then removed but the finger is not. The vaginal wall is stimulated with the inserted finger for several minutes. This should induce the vagina to begin contracting, which helps move the semen into the uterus. After stimulation, the finger is removed. At this point, the rear of the dog is elevated for 5 to 10 minutes. Do not push on the abdomen. Elevate the dog by grabbing the lower rear legs and elevating. Do not allow the dog to squat. After she has been elevated for 5 to 10 minutes, she can be allowed to walk around but do not allow her to urinate or jump for 30 to 60 minutes. After one hour, she can return to normal activity.
In selected cases, surgical insemination can also be done. After the uterus is surgically exposed, the semen sample is introduced into the uterus by a needle and syringe. This is not the most effective method of fertilization but may be required in highly valuable dogs in which puppies
are in great demand.Results With natural breeding (assumes 3 breedings in a heat cycle) there is an 80 to 95 percent success rate of pregnancy.
With AI using fresh semen, 62 to 100 percent success rate
With AI using chilled semen, 59 to 80 percent success rate
With AI using frozen semen deposited into the vagina, 52 to 60 percent success rate
With AI using frozen semen deposited into the uterus, 0 to 80 percent success rate