Mercury and Gemma frolic in the snow at 8 weeks old.
Over 250,000 Border Collies have been registered with the ISDS since its founding over a century ago even though they didn’t really keep comprehensive stud books in earnest until the 1940s. Registrations have remained steady over the last few decades with 5,000 – 7,000 dogs being born and registered every year. This is the founding gene pool for all Border Collies worldwide and save for a dash of “local flavor” in the form of a Kelpie, English Shepherd, Beardie, pre-ISDS Border Collie, etc. thrown in, it represents the lion-share of global genetics for the breed.
Despite sizeable numbers of dogs in the UK, Europe, America, and Australia and New Zealand, and despite having a “founding” population of several hundred dogs, the current genetic information in the breed has been distilled down to just 8 individual genomes worth of information.
The effective number of unique Border Collie genomes across the entire extant ISDS population is only 8.3 individuals worth of information.
Teun van den Dool ran the entire published ISDS stud book through genetic analysis software and discovered this:
- There are 643 registered foundation dogs with genetic influence on the current population.
- 0.01% (25) of all registered dogs determine 75% of the genes in the current population.
- Effectively the genes of only 8 of the founder dogs determine the genes in the current population.
He continues:
It seems that the current Border Collie population is dominated by a small number of dogs. Another way of looking at the gene base of a population is to define the foundation dogs (founders). These are the registered dogs with one or two unregistered parents. The unregistered parents could also be considered the founders but because they have no ISDS numbers it is not easy to find out which unregistered parents are equal for different registered pups. In that case the number of founders would be higher than in reality.
There are 3143 registered founders of which 1481 produced registered children. Only 643 of them have had influence on the pups born in the last five year.
A more detialed explanation of those 8 dogs:
This third algorithm gives EG, the effective number of different genomes from founders that are still present in the current population. It does so by simulating the random selection of a particular gene during the fathering of all dogs ever registered. After this simulation the genes in the current generation of Border Collies are counted. This simulation of the total Border Collie population is repeated many times (1000 in this case) and the average occurrences of the genes are calculated from the results. For the current ISDS population the effective number of founder genomes is EG=8.3. So effectively the genes of only 8.3 founder dogs are present in the current generation of approximately 25000 ISDS registered Border Collies. Amazing isn’t it?
Figure 4 shows how the different (effective) numbers of dogs have evolved over generations since the fifties. Before 1950 the pedigrees are incomplete and show a wild behavior starting at zero around 1900. Since 1980 the effective numbers are almost constant. Sometimes even a bit increasing due to ROM (Registered On Merit) dogs or dogs with otherwise unknown parents. So the main selection took place before 1980. Maybe not accidentally the last big reduction in genetic diversity (1965-1975) coincided with the rising star of Wiston Cap 31154.
A little extra explanation for those puzzled which those 8 ‘effective’ dogs are. They do not exist in reality, we cannot point at these 8 individual dogs. You should think of it as an amount of genes spread over all dogs. Many dogs have the same genes and only very few different genes are present in our dogs, only an equivalent of 8 dogs. That is what ‘effectively’ 8 dogs means.
Another way of looking at it is, suppose that we would have 8 founder dogs with differences in their chromosomes. We let them mate with each other randomly to produce a new generation of 25000 pups. This new generation will have the same genetic diversity as the current ISDS population. In this example we can point at the 8 effective dogs but in reality we cannot, the chromosomes have been selected over many generations from many dogs.
You might think ‘but Wiston Cap must be one of them’. Well, he surely caused a considerable reduction in the effective number of genomes but he did not add anything. He just caused a particular selection of chromosomes from its ancestors to become more dominant.
This analysis is an example of how current population numbers don’t tell the complete story of breed health. Regardless of current size, past bottle neck events mean that hundreds of thousands of Border Collies across the planet still only hold the genetic information of 8 individual genomes. It just might be the case that a small or even rare breed with only a few hundred members contains more unique genetic material than Border Collies do.
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But to make this analysis, you have to know all about how to win herding trials.
retrieverman recently posted..Chat room
“A little extra explanation for those puzzled which those 8 ‘effective’ dogs are. They do not exist in reality, we cannot point at these 8 individual dogs. You should think of it as an amount of genes spread over all dogs. Many dogs have the same genes and only very few different genes are present in our dogs, only an equivalent of 8 dogs. That is what ‘effectively’ 8 dogs means.
Another way of looking at it is, suppose that we would have 8 founder dogs with differences in their chromosomes. We let them mate with each other randomly to produce a new generation of 25000 pups. This new generation will have the same genetic diversity as the current ISDS population. In this example we can point at the 8 effective dogs but in reality we cannot, the chromosomes have been selected over many generations from many dogs.”
This is a really fabulous, simple explanation, and if I ever need to explain it, I am going to steal it.
What kind of immune system problems are there in Border Collies? Allergies, digestive issues, how common are they?
Jess recently posted..Afghan Hound Puppy- 1936
Yeah, Teun is great, I think he should get an award from the Border Collie powers that be for service to the breed by digitizing the stud book all on his own efforts and dime! Plus, English isn’t his first (or perhaps second or third) language and he comes up some great essays on Border Collies.
Teun says this in that essay:
Sadly, the data he presents is all about inbreeding and genome loss, it’s not about actual health at all. So I don’t think we can conclude anything about BC health. That is an open question.
The *Problem* in Border Collies is that the culture is like John Wayne. Cowboy types don’t talk about what hurts and Actors don’t disclose their genetic peccadillos. There’s also the faith healing of “work” theme that’s present in the breed. Not only the idea that work is a sufficient culling factor to weed out most disease, but that work should be valued more than health: Denise Wall who co-wrote that recent BC book about a working dog and a service dog, featured on PetConnection, has an essay where she posits that Hip Dysplasia might be beneficial to Border Collies and allows them to move better.
There’s also a lot of “show no weakness” due to the BC being admitted to the show registries. Keep it in the family, don’t give the enemy ammunition. The show community is a little better in publishing disease, but only when they HAVE to or when the results are good.
I haven’t found anyone who has done MHC testing on Border Collies. No sweeping health surveys.
There’s also extreme denialism about any sort of “new” disease that pops up. NO ONE was talking about “failure to thrive” or wiped out litters before there was an identification and test for Trapped Neutrophil Syndrome. It was an issue that was off the radar. Once there was a test for it, it was a “show only!” disease from New Zealand or Australia. Now, we know it’s in ISDS only working lines.
I imagine that before there was a test, this disease was covered up by “must have been parvo that killed those puppies” or “it was a small litter” and not much discussion about the failure rate of puppies. The internet is changing that.
When I get some extra cash, I’d like to do MHC testing on my stock. We’ll see what it says then.
This is all fascinating! Are there still working farm-bred more-or-less border collies that are not closely related to the registered lines?
Yes, I believe in the UK, Aus/NZ, and the US there are unpapered, working bred, ad hoc Border Collies and BC mixes. It’s hard to put a number on them, obviously, but they are out there and I believe that they are likely to be less focused on recent trialing dogs and more regional working (as opposed to trialing) dogs.
In doing pedigree research, there are farm dogs of only recent register on both my lines, and one of my puppies was bred to an unregistered working border collie and she and her offspring are working now on several cattle ranches. So it exists. I don’t know how much of that blood makes its way back into the main gene pool. The ISDS data doesn’t look good in this respect. While there are ROMd dogs (Registered on Merit), all of them combined don’t measure up to a significant influence.
Obviously some ad hoc unpapered Border Collies have gone on to contribute to now recognized breeds, like the McNab dog.
Also, while there have been a very very few notable non-Border Collies brought into the gene pool, like the Bearded Collie Turnbull’s Blue, this is so far a very rare event.
That’s rather what I suspected. Here in the UK I have met quite a few working-bred ‘border collies’ that don’t look much like the ‘classic’ border collies you might see in a dog breeds book. The working Labradors, by contrast, are far more uniform in appearance.
My rescue is BCxSpringer – and I’m guessing that’s an unregistered BC given his background. I’ve been told it’s a fairly common cross to produce a general purpose farm dog in some parts of the UK.