Following are three articles recently published in the May 2003 issue of the Verein Deutsch Drahthaar Group North America Newsletter concerning artificial insemination (AI). They are reprinted with the permission of GNA Newsletter Editor Larry Houck. The first is a Point of View article by Larry Houck introducing the pros and cons of allowing artificial insemination in a breeding program. Next GNA Breed Warden Lynn Whitely suggests that GNA should be making a policy on AI that would be the basis for a proposal to VDD to allow artificial insemination as part of the breeding program. Finally there is an article by Jim Hickie of Australia that discusses various issues to be considered in AI.
Artificial Insemination Is It In The Future?
by Larry Houck
Newsletter Editor, VDD-GNA
At the present time VDD does not allow Artificial Insemination to be used in its breeding program. However, the difficulties that arise trying to find the best male to breed with the best female seems to become a challenge when line-breeding or a specific breeding is being considered in ones plans for their breeding program. The challenge with travel over long distances and its associated costs as well as timing are at times very difficult to deal with. It is a well known fact that airlines are becoming much more difficult to work with as groups and safety concerns continue to put up roadblocks to accomplishing favorable transportation.
As one examines the subject of artificial insemination. There are many variations of AI to consider. There is dog-to-dog artificial insemination, fresh-extended (chilled) semen insemination, and frozen semen insemination. Techniques of AI include vaginal deposition, surgical implant, and trans-cervical insemination. Studies have been published with convincing evidence that every semen preparation — fresh, fresh-extended or frozen — will produce larger litters if semen is deposited directly into the uterus, especially with trans-cervical technique. That being said, fresh and fresh-extended semen give decent results with vaginal deposition.
Overall variability in pregnancy success rate for artificial insemination methods:
Natural service: 80-90%
Fresh AI, intravaginal insemination: 62.3-100%
Chilled AI, intravaginal insemination: 59-80%
Frozen AI, intravaginal insemination: 52.6-60%
Frozen AI, intrauterine insemination: 0-80%
The use of artificial insemination in canine breeding offers a solution to a number of situations that may prohibit or complicate natural breeding. Such situations include anatomical deterrents (such as a narrow vulva and vagina in a virgin bitch), unwillingness to breed (dominant/aggressive behavior of the bitch or submissiveness in the male), weakness or pain in the spine or hind limbs (in geriatric studs still providing service), reducing risk of sexually transmitted disease to the stud (brucellosis), or geographical distance between stud and bitch.
The big benefit to AI is to diversify the gene pool, giving breeders the ability to breed to the best dog available to them, instead of “old Duke” down the road because he’s close. One should improve the breed.
There are some apprehensions by some however about International AI. There is the possibility of expanding the gene pool, but on the other hand, VDD/GNA is just getting to the point where it is producing and FULLY testing some of its homegrown stud dogs. GNA still has a long way to go in this, but if breeding to some strongly desired dog from Germany becomes as easy as placing an order, it is feared that there may be less incentive for buyers of GNA male puppies to fully test and promote its dogs. Many breeders may for whatever reason buy into the idea that German dogs are better and are easier to sell puppies out of, and/or demand a higher price. Is this being seen in the United States now? Germany doesn’t have better dogs, just a better selection of fully tested dogs. Another question that arises is one of having doubts about how many German Stud owners would be willing to jump through the hoops necessary to send semen to the US, especially if the stud has a full dance card in Germany.
The use of Artificial Insemination often means the available gene pool of a given breed will be broadened, increasing the possibility of genetic selection for constructive traits and against medical and/or behavioral problems. Should the use of AI also include the use of semen from stud dogs of the past?
While artificial insemination is often carried out with a fresh ejaculate, actions of extending and chilling canine semen have been recently developed to preserve sperm viability, allowing transport to distant locations. The use of canine chilled extended semen may be indicated in any distance breeding between a healthy, reproductively normal bitch and stud to avoid the risks and stress of shipping the animals. After shipping, bitches may abruptly “go out of season” and fail to ovulate, which is mostly likely a result of a stress-induced change in hormone secretion. Both bitches and stud dogs frequently fail to thrive in a strange environment, and show decreased reproductive efficiency as a result. Airline travel may be risky, and is often prohibited during periods of temperature extremes. In addition, many stud owners limit the use of a dog for breeding because they prefer not to host a bitch, either due to the disruption caused in the kennel and/or the responsibility of caring for someone else’s valuable bitch and managing the breeding. Shipping chilled extended semen therefore enables breeding to occur that would be unlikely otherwise.
While the possible benefits are great, it is important to remember that breeding with chilled extended semen bring in challenges that are not factors when dogs breed naturally. If all steps in a chilled extended semen breeding are performed properly, the chances of conception are close to that of a natural service.
It is always very important that all parties involved understand the steps required and are committed to carrying them out.
What could be next? Freezing Canine Ovarian Tissue. Samples for Cloning.
Artificial Insemination and the Deutsch-Drahthaar
by Lynn Whiteley
Breed Warden, VDD-GNA
In general I am in favor of GNA putting together a proposal to VDD to allow the use of Artificial Insemination. First off, any proposed use of AI would have to be for the betterment of the DD breed, not just for the convenience of the breeder. The proposal would of course have to satisfy any concerns VDD might have about maintaining the integrity of the breed. This may include regulations similar to what the DKV has implemented in their AI policy. DNA testing for parentage could be a requirement. This along with extra expenses for collection, shipping, and insemination could make AI more expensive than a normal mating, but it could also make possible to breeders the use of stud dogs that otherwise are not. Improvement of the breed through breeding to the most appropriate stud should be our goal.
I think that a proposal would be aimed primarily at the use of the chilled semen method where overnight delivery is possible, but should not exclude the possibility for the use of frozen semen when longer distances make the chilled semen method unworkable. In the past decade there have been some advancements in the methods of insemination of both chilled and frozen semen. With the rising costs and at times unavailability of shipping of animals by air, I think that this is something we need to explore. This could also be a big help to GNA Breeders that are not located in areas where there is a lot of VDD activity.
I plan to take suggestions and work toward developing an AI policy to present to the GNA Ex. Board, and then eventually if there is a consensus to move forward, we would present it to the VDD Ex. Board for consideration. I would appreciate any input from members that have an opinion on it.
Artificial Insemination
Outline and Discussion of the Issues Involved
by Jim Hickie, Australia
The following article received from Jim Hickie, (Australia), provides an expert and authoritative commentary and discussion on several key aspects of AI, including moral and ethical issues.
The first recorded artificial insemination in dogs was done by a researcher named Spallanzani in Italy around 1780. So much for Ancient History. More recently the early experiments using thawed frozen semen for artificial insemination met with poor success rates — mainly due to the fact that the technology carried over from other species did not adapt well to dogs. However in the last thirty years dramatic improvements have been made as researchers have identified and solved the problems associated with storing canine semen and getting ovulation timing right. Today experienced practitioners in this field achieve conception rates that are comparable with those achieved in normal matings although the number of progeny of such litters might average slightly fewer than those from normal matings.
These results have been achieved by researchers developing improved diluents and extenders to better store and thaw semen and equally important, improved techniques for determining the time of ovulation in the bitch. It would appear to me that there is still room for improvement in the post thaw viability of frozen semen. Fresh semen from a natural mating can survive for up to seven days in the reproductive tract of the bitch while thawed frozen semen has a life in the same environment of not much more than seven to twelve hours. This will explain why it is of paramount importance to accurately determine the time that ovulation takes place within the bitch — another area in which improvements could still be made.
In recent years a number of techniques have been developed (mainly in the USA) to more accurately determine the time of ovulation in the bitch. The developers of each technique claim greater accuracy and simplicity than the others but quite frankly to date none seems to be any more accurate than the progesterone assay, which is a blood test (usually performed in a pathology lab) and which uses the rise in progesterone level to indicate the time of ovulation. In Australia to date most inseminations have been done surgically. The reasons for this are firstly that the technique is very economical in the use of semen (an very large breed dog usually produces 16-24 straws / ejaculate) and surgical implantation involves the use of only two or three straws of thawed semen and secondly the semen is placed where it is going to be most viable, — the results are thus rather good.
For example from the nine frozen semen inseminations we have had done in the last six years the average litter size has been 6.4 and litters have ranged from one to thirteen puppies. Economical use of the semen is particularly important where the semen has come from remote places or is from a source that can no longer provide semen due to age or even the death of the donor. It is worthwhile noting that semen quality deteriorates as the dog gets older and even though a dog is capable of siring normal sized litters once he is over seven it is possible that semen may not be suitable for freezing.
In the Scandanavian countries and increasingly in other European countries and in the USA transcervical insemination via the vaginal tract is the preferred method. Since there is no surgery involved, anesthesia is not required and practitioners of the technique have recently claimed successful inseminations with as few as two straws. In other words when practiced by competent operators this technique is equally as successful as the surgical method. Prior to these recent developments up to twelve straws were required for this type of insemination. Without getting involved in technical details that is about where the technology is at the moment. There is obviously scope for improvements in a number of areas, particularly in relation to the exact timing of ovulation in the bitch and more importantly in developing better diluents, extenders and freezing techniques for semen.
Before considering what the future may hold perhaps it might be a good idea to consider why people use this technology and what advantages it offers. Firstly the technology helps overcome the problem of distance between a dam and a potential sire — particularly where quarantine is involved. Nowhere is this more important than in those countries where the gene pool is small — countries like Australia, Sweden, Norway, etc. It is little wonder that these countries have been at the forefront of development and experimentation in this field as well as being the early pioneers. In our breed there are only two countries where the numbers are such that a diverse range of types and bloodlines are available, the U.S.A. and England. To a lesser extent the same applies to those European countries where dogs can move from one to other without quarantine restrictions.
In the countries where the breed is small in number it has been traditional for breed enthusiasts to import dogs from those places where the breed is strong. Because the dog they really wanted was not for sale or totally unaffordable usually a son of the preferred dog was imported. Occasionally this produced the desired result in the first generation but more frequently not. With the availability of frozen semen the breeder can now get to use the preferred sire rather than a son. The breeder is thus using a sire that he knows is pre-potent for those characteristics he is looking for and consequently saves himself at least a generation of time. Time is the most valuable resource in a breeding program — you can rarely buy it. That reminds me of a comment Jay Hafford made in an A.H.R interview published earlier this year. “I feel that there isn’t enough time in a human lifetime for me to create quality out of mediocrity in a breeding program.” Time is really of paramount importance in a breeding program.
The second advantage of freezing semen is that it provides the opportunity to store the genes of great and successful sires over a long period of time — even long after their death. This is not a viable advantage in those countries where the controlling Kennel Club will not register progeny from an AI where the donor sire is deceased. USA and the UK in particular. Contrast this situation with Australia where in 1993 and 1994 litters were produced by two sires whose semen was collected back in 1976, some seventeen years earlier. In answer to the question that immediately comes to many people when confronted with this information, the life of properly collected and stored frozen semen is indefinite. I am informed that some Swedish researchers, using mathematical modeling, have predicted a storage life of 4000 years under ideal conditions. The third advantage of storing frozen semen over a long period of time is that it may provide the opportunity to get back in a breeding program prior to the development of current hereditary genetic faults. For example there was a time when elbow dysplasia was almost unknown in G.S.D. The problem has arisen because some dogs that carried desirable characteristics and were used extensively also carried this problem. It is now very difficult to find lines that are totally free of the problem.
There are obviously other advantages but these three are probably the most significant from the point of view of a breeder. Of course there is one big disadvantage COST! Currently costs run to $250-$350 for semen collection, evaluation, freezing & storage. Add to this a stud fee and the other expenses incurred by the stud dog owner including in many cases tests on the dog required by the quarantine authorities of the country importing the semen (if it is being exported). If international shipping is required then add anything up to $500-$700, since the airlines classify liquid nitrogen as a dangerous or hazardous material, which gives them the right to charge exorbitant freight rates. And then at the other end there are the usual customs clearance costs, plus the cost of storage till the semen is used then the veterinarian’s charges for doing the insemination and the ovulation timing tests, usually another couple of hundred dollars. All this is much more expensive than shipping a bitch to the most expensive stud dog and even with the current advanced state of the technology the risk of failure is still somewhat greater than with a normal mating.
Now perhaps it is time to draw some comparisons of the KC regulations that apply to the use of frozen semen in various countries. Back in the 1970’s when the early experimentation in the storage and transportation of frozen semen was taking place we in Australia were fortunate to have a veterinarian who was keenly interested in research and experimentation in this field (it was he who collected the 1976 semen mentioned earlier). His name was Harry Spira and he was also an administrator in our Kennel Club. In this second role he was able to bring his influence to bear to introduce regulations that allowed breeders to take advantage of the potential of this technology. The result has been that in some breeds there has been a dramatic improvement in breed quality in a very short period of time (since 1989) while in others the gene pool has been considerably widened. Regulations similar to ours seem to have been adopted in a number of Scandinavian and European countries.
The picture in the United States and Great Britain is somewhat different. The attitudes of both the AKC and the English KC would seem to actively discourage the importation of frozen semen from foreign countries. Firstly the AKC requires that a “letter of intent” be sent to it detailing the planned insemination including the names of both parents and the expected date if insemination etc. In addition the AKC has a policy that only sufficient semen for one insemination should be imported at a time. Now considering the costs of collection and transport — doesn’t that add to the expense? Americans are renowned as ingenious people and some seem to have defeated the intent of this restrictive regulation even though it involves some additional paperwork. Similarly it would appear that the problem of using semen from dogs that are deceased is easily overcome by not advising the Kennel Club that the dog has died.
The English Kennel Club is equally determined that their gene pools shall not be contaminated by foreign blood. They require that its permission be sought for each AI involving a foreign sire and it usually does not approve such applications. Recently in the case of Afghans a small number of such applications have been approved. In reality the attitudes of these two very large (and conservative) organizations means that some of the great advantages of the storage of frozen semen are denied to their members.
One can only imagine what the reaction of these ultra conservative bodies will be to some of the artificial breeding techniques that are about to arrive on the dog-breeding scene. To date we have only been involved in preserving and transporting the genes of the male. In other species techniques for preserving ova are well established and in some species — sheep, goats, cattle etc. — techniques for super-ovulating females, inseminating them and then flushing embryos to be frozen and stored for later implantation into surrogate mothers have been practiced for a few years. Recently in the USA a Great Dane surrogate mother produced three Whippet puppies and five Golden Retrievers. You will not be surprised to learn that the AKC does not want to know about it.
The jump from the laboratory experiment to the practical world of breeding is but a short one. There is really no practical reason (other than cost currently) why we cannot freeze embryos for later implantation — even years later — or to export them to other countries. This is technology that is here now; but how will the Kennel Clubs handle this situation — if at all — and what are the moral and ethical considerations so far as breeders are concerned? Is the use of technology such as this any different from the selection processes we go through as breeders and does the adoption of these breeding methods only accelerate your selection processes?
Of course one does not need a crystal ball to foresee that with the advent of genetic engineering we may be able to eliminate many of the hereditary problems that currently plague our breeds — fortunately Afghans have very few of these. Will these advances in breeding technology be accepted by the regulatory authorities? And in the future what of cloning???
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