Breed Status

1. Breed history
2. Current number of dogs and locations
3. Pedigree information
4. Health information

Threats to sustainable breeding

1. Small population size
2. High inbreeding
3. Inbreeding depression
4. Small effective population size (Ne)
5. Health issues
6. Not enough breeders
7. Inadequate guidance for breeders

Breed-specific concerns

1. Iconic Norwegian dog of high cultural importance
2. Preservation of unique anatomical and behavioral traits​

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• Increase the size of the population
• Reduce breeding age of bitches to 15 months
• Breed at least one litter from every healthy bitch
• Develop methods to assess breed-specific traits
• Develop methods to assess temperament and breed-typical behaviors
• Use DNA genotyping to assist mate selection
• Develop a comprehensive strategy for data collection on dogs, litters, health, etc.
• Develop an efficient breeding strategy using population genetic analyses
• Assess efficiency of breeding strategies using appropriate computer models

​

From the start, the Norwegian breeders progressed step by step following a planning strategy, the major outline of which was developed for general goals (e.g., increase the size of the breeding population), with tweaks and adjustments as necessary as the plan progressed. These breed-specific breeding plans are called "Rasespesifikk Avls-Strategi" (RAS) in Norwegian.

The first step in the development of a sound breeding strategy is determine what you have to work with, and a review of history to understand how past events have shaped the current population of animals. For this, they did a comprehensive review of history, documenting the historical use of the breed for Puffin hunting, events that affected population size and breeding such as disease outbreaks, legislation, changes in culture, kennel fires, and replacement of dogs with other hunting methods. They developed a pedigree database that was as complete and error-free as possible. They documented fertility, litter size, mortality, and disease when information was available. They also summarized historical changes in the level of inbreeding, number of sires and bitches in the breeding program, offspring per individual, and imports and exports.

​Threats to sustainable breeding
After assessing these data, they identified the problems that needed to be addressed and articulated the goals to solve them. For this, breeders worked closely with animal breeding experts and population geneticists at NordGen who assisted in developing and testing the particulars of the plan.

These were summarized as:
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​Breed-specific concerns
There's no point in doing a genetic rescue if the dogs produced at the end aren't the breed you started with. A critical part of any program is to have a clear picture of the critical traits of type that make the breed unique so the breeding program preserves those in the dogs that result. These traits would include physical features like size, color, coat type, proportions, shape of ears, tail, feet, and muzzle, and also instinct and behaviors, temperament, features specific to purpose, conformation including gait, shape of eye, proportions and planes of the head, and so on. A special consideration for the Lundehund is the preservation of their extreme flexibility in the shoulder and neck joints, polydactyly, ability to fold the ears, rotary front movement, and double coat that is waterproof and warm. Overall, the goal is to produce dogs with good Lundehund type that are healthy and fit for function.
​

​Development of a breed-specific breeding plan (RAS)
The specifics of the RAS planning schedule are in their document (download below), which is broken up into sections that focus on specific aspects of the breeding plan. You can review that document, but here are some of the highlights: 

​The size of the breeding population affects critical aspects of genetic management. As for the Condor, the success of the breeding population will hinge on increasing the census number of individuals as rapidly as possible. This will improve genetic stability (chance fluctuations of gene frequencies) and broaden the options for breeding. A top-level concern for the short- and long-term goals of the program was to increase the effective population size (Ne), setting a goal of Ne = 200 (90 males and 110 females) by 2020-2025, as well as increasing the total census size of Lundehunds in Norway to 1,000 by 2025.  It was stipulated that the highest recommended inbreeding coefficient is 3.25, based on a 5 generation pedigree.

You can download these two RAS documents, which lay out the information and goals for the Lundehund breeding program. Note that the date ranges are a bit different, which I suspect reflects updates in the plan as they progressed
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Download RAS Schedule (2014-2025):  Breeding strategy for the Norwegian Lundehund
Download RAS data summary (2014-2018):  RAS – breeding strategy for the Norwegian Lundehund

Many dog breeds are struggling to manage a growing list of genetic disorders at the same time as the options for managing inbreeding are becoming more and more difficult. Avoiding problems with the known mutations and lines producing complex diseases only shifts selection away from one corner of the gene pool and towards another, producing an ever-narrowing bottleneck that ultimately only makes matters worse.

The holy grail is discovery of a population of dogs that has been isolated for generations and contains genetic diversity long lost in the main population of dogs. Failing this, however, many breeds do in fact retain enough genetic diversity to improve health and open up new options for breeding. But when a breed reaches the limits of improvement using the diversity remaining in the breed, the only other option is to restore the genetic diversity that has been lost to selection and genetic drift. ​

The goal here is to outline a basic program to rehabilitate or rescue a dog breed that is facing challenges due to inbreeding, small population size, low genetic diversity, or other factors that make sustainable breeding difficult. The path to genetic improvement will be different for every breed, but the considerations are generally the same, so this can provide a rough template for the rehabilitation or rescue of any dog breed.

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Genetic assessment of the breed from pedigree & 
​DNA data

Central to the development of a plan for genetic rescue is information about the current
genetic status of the breed. The pedigree database is a primary source of historical genetic
information, and DNA analysis can now be used to supplement this with much detail about
actual genetic diversity, gene frequencies, inbreeding, relatedness, etc.

Historical Information From Pedigree Data

1. Number and identity of founder dogs
2. Changes in population size over time
3. Loss of genetic diversity
4. Changes in effective population size
5. Average inbreeding over time
6. Average kinship over time
7. Genetic contributions of founders
8. Addition of unrelated dogs (new founders)
9. Fraction of dogs used for breeding

Genetic Information From Pedigree Data
The pedigree database can provide a significant amount of critical data about the current genetic status of the breed, including several measures of genetic diversity, genetic composition of current dogs, size of the gene pool, relatedness of dogs in the population, etc.:

1. Level of inbreeding (coefficient of inbreeding, F, or "COI")
2. Genetic relatedness (mean kinship, mK, and average mK for the population)
3. Effective number of founders (fe)
4. Eeffective number of ancestors (fa)
5. Founder genome equivalent (fg)
6. Effective population size (Ne)
7. Origin of genetic variation

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Genetic assessment of the breed from DNA data

Genotyping using high-density SNP chips (e.g., Illumina CanineHD SNP chip; > 170k markers) can provide a wealth of information about the genetics of the current animals in the population, and it can also be used to estimate historical trends in effective population back hundreds of generations. Information from DNA analysis will be "realized" instead of "estimated" or predicted, because it is based on DNA marker status and not on probability of allele inheritance from pedigree data. 

Genetic information from DNA genotype analyses (SNPs)

1. Genetic diversity (observed and expected heterozygosity, Ho & He)
2. Genetic structure(Fst)
3. Current and historical effective population size (Ne)
4. Genomic inbreeding (as F)
5. Genomic inbreeding relative to the population (Fis)
6. Genomic kinship coefficients and kinship matrix
7. Fraction of polymorphic loci
8. Population genetic structure (e.g., principal components analysis, cluster analysis)
9. Genealogical relationships determined from DNA and cluster analysis
10. Assessment of disease risk without knowledge of the genes involved or mode of inheritance
11. Localization of inbreeding on individual chromosomes (runs of homozygosity, ROH)
12. Genetic relatedness to other breeds
13. Across-breed comparisons of patterns of homozygosity on the chromosomes (ROH)​

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Assessment of Potential Breeds for Crossing

The goal of a genetic rescue is ideally to restore a breed to its original genetic state. We rarely know what that is, but 

​Phenotype Information

1. Size and weight
2. Conformation (e.g., proportions, topline, tailset, head size, athleticism)
3. Specific features of type (e.g., ears, skull, coat  type)
4. Temperament and behavior
5. Purpose

Genetic Information

1. Inbreeding and mean kinship within cross breeds
2. Haplotype sharing of cross breeds with other breeds (indicating historical relatedness or crossing)
3. Genetic relatedness to rescue breed
4. Shared blocks of homozygosity with rescue breed
5. Potential to produce genetic diversity in F1 crosses

By Carol Beuchat PhD

Okay, what other things do we need to think about in the process of getting from generation 1 to 2, and from 2 to 3, and onward?

If we had a population of dogs that were healthy and terrific examples of their breed, and we wanted to replicate that in the next generation, what should we do? We should make copies of all of the genes in all of the dogs of our founding populations, mix those genes up, and package them into puppies that will become the healthy dogs of the next generation.

And for the next generation? We want to do the same thing. Gather up all the genes in that first generation, replicate every single one, give them a good mix, and distribute them in the puppies of the next generation.

Of course, we might want to change something about the dogs - make the legs longer, or produce more dogs of a particular color. We can use our skills as a breeder to preferentially breed the dogs with the traits we want, using the magic of selective breeding. We make more copies of the genes we want by breeding more of the dogs with those genes, and this changes the mix of genes in the gene pool in the direction of creating dogs with the traits we want.

In a perfect world, we could continue like this forever.

But our world is not perfect. Not every gene in the current generation will end up in a new puppy, either because we have chosen not to breed some of the animals (selecting for longer legs or whatever), or simply by chance. Over time, selection and random chance will shape the nature of the gene pool, changing the frequencies of genes little by little with each generation.

If we started with founder dogs of perfect health, we want to make sure all the critical genes for health get passed from generation to generation so we continue to produce healthy dogs. But what happens if we lose a few of those, either by selection or chance? The Dalmatian, for instance, inadvertently lost a critical gene for nitrogen metabolism, with the result that the dogs suffered from the formation of urinary stones. How did breeders fix that problem? They put the critical gene back in the gene pool. They did this by crossing a Dalmatian to a breed similar in structure (the pointer), then selected the offspring that inherited that critical gene, which is identical in all dogs. It was a brilliant and simple fix. With each backcross into the breed population, with selection of the offspring that inherited that gene, the frequency of the new gene increased, the fraction of pointer genes in the gene pool dropped exponentially, and in a few generations the dogs were genetically pure Dalmatian.

Now, we have technology that might someday allow us to go in and replace that single lost gene using something called CRISPR. But it was easily restored, not with technology, but with clever breeding in a single cross.

Back to our hypothetical breeding program. If we have been randomly (by chance) or deliberately (by selection) losing genes every generation, and all the genes in our founder dogs were essential for some function, we can expect some things are not going to not work like they're supposed to. These broken things become genetic disorders - allergies, temperament problems, low infertility, cancer, kidney disease, heart failure, and any of a very long list of canine maladies.

We understand why this happens.

If we start with a population of healthy dogs and want to keep them that way, there's one critical thing we need to do - make sure every single one of the "dog" genes - the ones necessary to build a healthy dog - is passed on to dogs in the next generation, generation after generation after generation. ​​Fiddle with the genes for type all you want, but you have to protect that original collection of "dog" genes that are necessary for building dogs that are healthy and fit to do what they were bred for.

This is the critical feature of preservation breeding. If we don't do this, we will break things.

Reality
To be fair - and realistic - it's nearly impossible to get all the genes of one generation into the next one, even if that was our sole aim as breeders. It certainly doesn't happen if we breed in a way that guarantees that some genes will be lost, and the two obvious ways this can happen is just by chance (an inescapable property of genetic inheritance) and by selection. Dogs that are bred will pass on only some of their genes; and dogs that are not bred pass on none.

If we replaced each critical "dog" gene lost like they did for the Dalmatian, we could keep a healthy population of purebred dogs forever. But if those critical genes are not replaced, there will be a deterioration in the health and function of our dogs over time. We should expect this; it's an inescapable consequence of losing genes from the gene pool each generation.

As purebred dog lovers, this is where we are. We have dogs with great genes for type - the particular traits that make each breed unique - but we have all sorts of problems with function, even to the point where breeding has become difficult in some breeds. We are hoping to cope by indentifying the critical genes that have been lost (by looking for the broken genes that have taken the normal gene's place), and we are spending millions studying the diseases that have resulted from loss of a particular critical gene. But neither of these efforts is solving the problem because we are still missing the normal copies of those critical genes.

What else could we do to solve this problem of missing genes? Why not the obvious? Why don't we just put those lost genes back, or make more copies from the dogs that have them? For some problems, it will be just a single gene as it was in the Dalmatian. In some cases, it might be multiple genes that together are necessary for some important function. But if we understand that every gene in those founder dogs played an essential role in building a healthy dog, it should be obvious that the only solution to a problem caused by missing genes is simply to put them back. In fact, this is really the only solution to the problem. Without that critical gene for nitrogen metabolism, the Dalmatian will produce urinary stones - in fact, any dog missing that gene will produce urinary stones. To solve the problem, put the normal gene back in the gene pool.

The key element of preservation breeding
If you want to have a sustainably breeding population of purebred dogs, you have to prevent the loss of the genes necessary for function from one generation to the next, or you have to replace the genes that are lost. We can't do the first if we practice selective breeding (which of course we do), so we have to solve the problem by replacement. To get back to healthy dogs, we need to restore the gene pool needed for health.

If a critical gene has been lost from one subpopulation of the breed (e.g., the dogs in the UK, or the bench lines of a retriever), it can be restored from dogs in another population that have retained that genes. In fact, there are breeding strategies that will reduce the loss of genes from a population over time by taking advantage of the ability to restore a lost gene from another population of dogs in the breed. This strategy is used by animal breeders that want to breed from a particular population of animals for many generations. It involves some clever population management and rotation of dogs among several populations that are maintained by inbreeding. In fact, this is how wild animal populations are able to persist for thousands of generations. Individuals from one population migrate to another, brining with them some of the genes that were lost over time in the new population. If populations are prevented from doing this, if they are isolated on an island for example, they eventually lose so many of the genes necessary for function that they go extinct.

For some dog breeds, critical genes might be lost from the entire gene pool, as the nitrogen metabolism gene was for Dalmatians. To replace those genes will require crossing to another breed that is selected to address the specific genetic problems most efficiently. Crossbreeding is routinely used in animal breeding to change particular  traits or to restore genetic health when there has been a loss of genetic diversity.  Cross-breeding is just one of several strategies breeders can use to achieve particular goals. Inbreeding, linebreeding, outcrossing, and crossbreeding are all used strategically by breeders to "shape" the gene pool so it best serves as the genetic pantry of ingredients you use in your breeding program.

The secret to producing healthy animals generation after generation - not just purebred dogs, but animals of any sort - is to maintain a gene pool that contains all the genes necessary for health. Protect the genes you have, and replace the ones that are lost, and you can breed healthy dogs forever.