The BBC in Scotland published an interesting article a while back about the rise in popularity of using breeders using Artificial Insemination and frozen semen rather than a natural mating with the nearest viable stud. It's a very interesting at how 21st century science is now replacing the guesswork (or "art" as some older breeders prefer to call it) of breeding, used in previous centuries.
Figures from the Kennel Club in the UK show there was just one AI puppy born in 1998, compared to 216 by 2014. The figures by now, would be much higher as more and more breeders try to expand their gene pools and create healthier dogs. It is becoming so common that along with the great benefit of adding fresh DNA, an unregulated market in frozen semen has arisen that some fear could introduce disease agents or genetic diseases from one country to another. This is such a concern in Europe that it's been proposed that regulatory measures regarding importation and exportation of semen should be included in EU legislation
The BBC article quotes a Scotland-based vet with extensive experience in semen freezing and AI, who says, "As well as expanding the gene pool there is another, more simple, reason why the popularity of AI has grown: convenience.
"The advantages of dogs not having to travel hundreds of miles to get mated are twofold, she says: less hassle for the owner and less trauma for the dog. A pot of semen travelling and dying doesn't really matter, whereas a dog dying on an aeroplane, dogs being moved from country to country as studs, puppies being sent abroad, there's high stress in that."
The article also points out that some bitches simply won't allow a male dog to mate with them - but they will tolerate AI. "It stops people holding bitches down to be mated by a dog, which I think is very offensive, and has gone on for decades. AI is less traumatic for everybody".
But AI is by no means as simple as chucking two dogs in a pen together and hoping for the best. It is time consuming and expensive and according to Kennel Club Secretary, Caroline Kisko, "the procedure is the preserve of "good" breeders. Some sort of fly-by-night who's breeding the odd litter is never going to bother with AI. It costs too much money."
The estrous cycle in dogs is divided into four stages: proestrus, estrus, diestrus (or metestrus), and anestrus. AI is performed during estrus because that's when ovulation occurs, so that means progesterone testing the bitch several times prior to mating to determine where they are in their cycle and then confirming it with a vaginal cytology swab (as the cycles progress, epithelial cells change from small parabasal cells with large nuclei to larger intermediate cells and then to very large cornified cells easily seen under a microscope).
There are some other downsides, too. Jemima Harrison, producer of the 2008 Pedigree Dogs Exposed programme that caused Crufts to loose some of its major sponsors over concerns about health problems suffered by some pedigree dogs after years of inbreeding, is critical of AI - unless it is used for genetic diversity.
The BBC points out that "on her blog, she (Jemima Harrison) points out that some breeders use the practice to mate dogs such a bulldogs whose physical shape prevents them from breeding naturally.
"She says the practice "circumvents natural sexual behaviour patterns" that ensure survival of the fittest ans argues that bitches may choose or refuse to mate with certain dogs for a genetic reason - reasons which may elude the "co-efficient of inbreeding", used by humans to give a statistical measure of relatedness between two animals.
"But on the whole," says Sue Finnett of UK Clone, "the people who are doing this do tend to have a deep knowledge of their breed so they spend a lot of time researching where they're going to get the semen from."
"The Kennel Club have relaxed some of their rules concerning AI over the past few years. But some still exist. "The main reason behind the rules in the first place is that we want to be sure that animals continue to be able to mate naturally," says Ms Kisko.
"There are also restrictions in place to avoid AI being used for dogs with genetic or health issues.
"In the US, it's a different story - AI is much more widely used, due to the geographical distances involved in breeding one dog with another from a different state.
"Dr Cattanach - the geneticist who first tried AI in the 70s - describes some of the justifications for its usage in the States as bizarre. "I don't see any problems with the technique but I worry a lot that it is likely to be used for the wrong reasons," he says.
"In one area, however, everyone seems to be in agreement: as long as care is exercised, and the technique is not just a sticking plaster for dogs which can't mate naturally, AI is justified when its purpose is to widen the gene pool."
References
Bitch fertility after natural mating and after artificial insemination with fresh or frozen semen , Journal of Small Animal Practice 25(9):561 - 565
