Allowing dogs to mate naturally is undoubtedly the simplest and least intrusive method of breeding. However, in today's modern world with advanced technology, Artificial Insemination (AI) becomes very convenient, especially when natural mating is not feasible.
Several factors influence the chances of pregnancy when using artificial insemination, such as the type of semen (fresh or frozen), its quality and quantity, the age and fertility of both the stud dog and the bitch, the site of semen deposition (intrauterine or vaginal), and the timing of insemination.
We have done all different methods and here are our observations:
Artificial insemination techniques
TCI - Transcervical insemination - the semen is deposited directly into the uterus to maximize the chance of pregnancy. This method of AI has the advantages of being anesthetic and sedation free, non-surgical, and relatively stress free. It also has the distinct advantage, in comparison to surgical artificial insemination, that more than one insemination can be carried out during the bitch’s heat.
Transcervical insemination may not be a feasible option for some bitches, typically for behavioral reasons. There have been some developments with the canine transcervical insemination endoscope. A new longer and slimmer scope is specifically designed for transcervical insemination in dogs. This facilitates transcervical insemination in large and giant breeds, as well as maiden bitches.
We have performed numerous TCI procedures using fresh, fresh chilled, and frozen semen. The process takes less than 30 minutes, with the sperm being placed directly into the uterus. The cost for TCI ranges from $450 to $600 for the procedure, in addition to several progesterone tests ($90-$120 each) and likely a pre-breeding exam for the bitch ($150) to ensure she is comfortable with the veterinarian handling her rear. During the procedure, an endoscope is inserted into the vaginal cavity and through the cervix. A skilled reproduction veterinarian conducts the entire process, and owners can watch it on a screen. Once the endoscope is inside the uterus, the sperm is released. Most females handle the procedure well, and sedation is not required. The only time she might need assistance to remain still is when the endoscope passes through the cervix, which may be itchy or uncomfortable for her, but it lasts only a few minutes.
If the TCI is performed during peak ovulation and the sperm quality is good, the chances of success are quite high. We have achieved success in 9 out of 10 cases.
The only time we succeeded with frozen semen was when we performed insemination by TCI at a progesterone level of 20.8.
Vaginal insemination
When natural mating is not possible, breeders will sometimes perform vaginal AI using fresh or chilled semen. There are different reasons why breeders could perform vaginal insemination, sometimes a maiden female will not allow a stud dog to mount her, sometimes a stud dog is taller/shorter or there is time constraint - as completing vaginal insemination is quick and once you know what you are doing - can be done in less than 10 minutes. Semen is collected and injected into the very end of the vagina can result in pregnancy and litter sizes equivalent to natural mating.
There are many different types of catheters that can be used for vaginal artificial insemination and they are relatively inexpensive ($20/kit) . Breeder will insert a special artificial insemination catheter into the very end of the vagina. At this point a bulb at the end of the catheter is inflated to mimic the swelling of the dog’s bulbus glandis during mating. This not only prevents back flow of semen, but stretches the vaginal wall resulting in oxytocin release and stimulation of vaginal and uterine smooth muscle contractions, facilitating transport of the sperm into the uterus. After the bulb is inflated, fresh semen is slowly injected down the catheter into the far end of the vagina. This is then followed by warm canine semen extender which functions to help flush the semen into the uterus in the same way prostatic fluid does during natural mating.
This is a technique that can be used in all bitches, is non-invasive, requires less skill and equipment than intra-uterine artificial insemination techniques, and therefore is also more economical. It is often used in maiden bitches and studs that fail to “tie” or mate, which can be due to several reasons.
Vaginal artificial insemination is not the preferred method for use of frozen-thawed semen. As well as the greatly reduced lifespan mentioned previously, frozen semen breeding units contain significantly lower numbers (i.e. 100 million motile sperm per “AI dose”) than a fresh or chilled insemination dose. Therefore, deposition of low numbers of fragile frozen-thawed sperm into the hostile vaginal environment results in low numbers migrating through the cervix into the uterus and reaching the fallopian tubes (oviduct), the site of fertilization. This obviously results in a lower pregnancy rate and litter size.
We have done vaginal AI twice - once at home and one time at the vet's office - we were not successful both times.
Surgical intra-uterine insemination
This technique involves a general anesthetic and surgery with associated risks. An incision is made into the abdomen, the uterus is then identified and exteriorized. The semen is then injected directly into the uterine horns. It can only be carried out once during the bitch’s heat. Further, surgical insemination does not increase conception rates or litter sizes.
This is the most invasive procedure and we have done it twice, as this is the "recommended" way to inseminate when using frozen semen. Both times it costs us around $1700-$2000, required our dog to be hospitalized and resulted in no puppies.
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