The Flat Coated Retrievers have been found to have relatively low levels of  biodiversity as a breed, but what they have is relatively well distributed compared to that of other breeds like Standard Poodles, Golden Retrievers and Dobermans. Breeders should plan litters with IR below breed average to decrease inbreeding and an average OI (outlier index) above the breed average in order to maintain biodiversity and avoid losing existing diversity to genetic drift. What is the outlier index? It’s a measurement on BetterBred that tells you how typical or atypical a dog is in relation to its breed. When the average OI for a breed is high, this means that there isn’t a single specific genetic bottleneck and that most of the genetics of the breed are not very typical or atypical. These breeds tend to be healthier with less breed specific disease.

The Parents

Obviously, selection for breeding mates involves more than genetic diversity. We also want the type, temperament, drive, pedigree, etc. in our resultant puppies, just as we always have before.

This is the sire. Let’s look at the key points:

The DLA: Both of his DLA haplotypes are common and well represented in the Flat Coated Retriever breed. 1017/2005 is the most common DLA haplotype in this breed.

According to UC Davis, the least common DLA haplotypes in this breed are: 1035, 1065, 1066, 1067, 1143, 1170, 1171 and 2014, 2017, 2046, 2048, and 2083. The rest of the DLA haplotypes in the population are well represented. So, when all else is equal in a breeding, I might opt for a mate with the less well represented haplotypes in order to preserve them in the breed. Once haplotypes disappear from a breed, they can only be restored by an outcross to another breed.

Outlier Index (OI): His OI is right at breed average. As this number drops, a breeders are breeding toward a genetic bottleneck, which is when the genes of a few ancestors become very common in the majority of a population. The OI of this breed is at a good level, so breeders with individual dogs that have lower than breed average OI can easily raise them in their puppies by looking for mates with higher OI.

Average Genetic Relatedness (AGR): I fondly call this the “more breeding mates” measurement. If you select for a lower AGR, you will have more unrelated options for your potential breedings. This tells us how closely a dog is related to other dogs in our database. The higher it is, the more dogs he is related to. He has an AGR of -.03, which is lower than breed average. This means he is less related to dogs in the database than the typical Flat Coat in the database.

Internal Relatedness (IR): And finally, the inbreeding estimate. He has an above average IR value, meaning he is slightly more inbred than the average Flat Coat.  A high inbreeding measurement would be above .15, according to Dr. Pedersen.

This is the dam. Let’s look at the key points:

The Dam: CH Athercroft Quesorahsorah JH,SHU

The DLA: Similar to the sire, she is homozygous for one common DLA haplotype.

According to UC Davis, the least common DLA haplotypes in this breed are: 1035, 1065, 1066, 1067, 1143, 1170, 1171 and 2014, 2017, 2046, 2048, and 2083. The rest of the DLA haplotypes in the population are well represented. So, when all else is equal in a breeding, I might opt for a mate with the less well represented haplotypes in order to preserve them in the breed. Once haplotypes disappear from a breed, they can only be restored by an outcross to another breed.

Outlier Index (OI): Her OI is a little below breed average. As this number drops, a breed is breeding toward a genetic bottleneck, or genes that are represented by the majority of a tested population. This can tend to concentrate disease genes as well. The OI of this breed is at a good level and this will be easy to raise in the next generation by breeding her to a dog with higher than breed average OI.

Average Genetic Relatedness (AGR): I fondly call this the “more breeding mates” measurement. If you select for a lower AGR, you will have more unrelated options for your potential breedings. The higher this number, the more dogs she is related to. She has an AGR of -.19, which is much lower than breed average. This means she is very unrelated to more dogs in the database than the most of the Flat Coated Retrievers in the database. This may change as more of the population is sampled.

Internal Relatedness (IR): And finally, the inbreeding estimate. She has a high IR value, but this can be easily lowered by selecting an unrelated breeding mate. A high inbreeding measurement would be above .15, according to Dr. Pedersen.

So, the next question is, how do they look together?

The Litter Prediction

The predicted litter was a category 10 breeding. Categories range from category 10 (unrelated) all the way to 1 (identical twins.) We generally recommend Category 6 and above, because when you go to the lower categories the level of inbreeding will be much higher,  the genetic distance between the potential sire and dam will be tighter, and therefore risks of recessive diseases are higher. We typically recommend running a test breeding to ensure that the predicted offspring will not have many potential puppies fall above the high threshold for inbreeding, which is generally considered to be around .15 IR. Now, there may be instances that you would breed for a higher IR, especially if your dogs are from a bottlenecked breed and you have a very uncommon dog/bitch. Why? Because those genetics are underrepresented in the population and could be easily lost through genetic drift, so at times a low IR may be sacrificed in order to maintain an unusual line and its less  frequent genetics (as long as the line is healthy). However, in this breed, the genetics are well distributed with a lot of biodiversity, so can rely more on maintaining low inbreeding rates in their offspring while selecting for health and breed type.

What do you see when you look at this predicted breeding?

The Key Points

Outlier Index (OI): The predicted range of this litter is .16 to .42, so puppies could fall anywhere from far below breed average to well above it. The lower this number, the closer one might be breeding toward a potential bottleneck within a breed. The variation in predicted values is because each offspring will receive different genetics from the sire and dam. Each sire and dam has common, neutral, and uncommon genetics in comparison to the rest of the breed. The breed average OI for Flat Coats is .26, which is the third lowest breed average oi, with Standard Poodles and Dobermans below. The average for this breeding is .29, which is below breed average. The percentage of puppies falling above breed average is very high; you can see in the image to the left that 13.267% of the likely litter would fall at .29 which is above breed average for Flat Coated Retrievers. This is great as it will serve to help redistribute less common and neutral genetics in this population. 

Internal Relatedness (IR): The IR range for this breeding goes from very outbred at -.31 to very inbred at .37. However, when you go to the summary, you can hover over the graph and see just how many will fall in the highly inbred range of .15 to .30. It appears that a good portion of this litter would fall above .15. Why would this be with a Category 10 breeding? This gene pool is smaller than others, like Dobermans, so even dogs that are the most unrelated for this population will likely have some genetics in common.

DLA:  100% of the puppies from this breeding will inherit common DLA haplotypes, however all puppies will be heterozygous for different DLA haplotypes, which is theoretically good.

The Offspring

This is the tested offspring: “Journey” Athercroft’s Sioux Tanka’s Icimani .  Let’s look at the key points:

DLA: She received two common DLA haplotypes.

Outlier Index (OI): Journey’s OI fell just above the predicted average for this test breeding, which was within the predicted litter range. It means her genetics are less typical for the breed than the typical Flat Coated Retriever in the database, but does not indicate health or quality. This helps breed away from any breed specific bottleneck.

Average Genetic Relatedness (AGR): This is the “unrelated breeding mate” measurement. The higher this is the less dogs in the database are unrelated to your bitch or dog. Journey’s is lower than breed average, so she will have more unrelated dogs in the current database than is typical for the breed. However, this may change as more of the breeding population is tested.

Internal Relatedness (IR): Journey’s IR fell below breed average, and on the lower end of the predicted litter range. Because her AGR is also so low, she will likely be able to find unrelated mates to continue to produce outbred puppies in the next generation.

So how might you use this? Say you have tested a full litter. You have two bitches you are considering for your program. One is highly typical for the breed, while the other has less typical genetics with a higher than breed average OI. This would allow you to choose between these two great choices, but also positively impact the breed for the future by breeding away from a potential bottleneck

Journey is pictured as the feature photo for this blog post. Thank you to the owners of these dogs for allowing us to use them in this demonstration!

Conclusion

This breeding predicted puppies with an average IR around breed average, with a significant portion falling at the high range of .15. The OI for the litter was well above breed average, which will help redistribute less typical and neutral genetics within this population. The resultant offspring fell well within the predicted values. There can be great ranges in genetics for each litter, and puppies can fall anywhere along those predicted ranges. Often we have seen that entire litters vary drastically from one another, both in inbreeding values as well as outlier index and average genetic relatedness (AGR). The choices we make with each breeding will affect our breed genetics and dynamics in future generations to come; we should be careful to select so that we lose less biodiversity to genetic drift.

Of course breeding is more than just about diversity, as we always need to pair selection for type along with selection for diversity. We cannot have one without the other, as breeding is done by passionate breeders because they love their breed, their lines, and the “family” they have created. BetterBred never suggests breeding for diversity to the exclusion of consideration of pedigree, type, temperament, drive, health etc. This is to add, not detract, from our breeding strategies.

Read more about Flat Coated Retrievers and why genetic diversity here: https://www.betterbred.com/flat-coated-retriever-presentation-2018/