Doberman DCM

Found this a few days ago, highly useful compendium of Dobe DCM stuff. No contact info or author info on the About page, or elsewhere but someone did a good job on this site. A couple good links I haven't seen here or elsewhere,
And I think there are a couple more studies/academic groups not yet included
But all in all
its a pretty level headed treatment,
at layman's level understanding...

So kudos and thanks to whomever put this together and hosted it.

Just for fun, as an example of using AI as a search tool, on a complicated and debated topic here are resukts on a query using SuprGrok (currently highest rated AI in use in science and health care data searches, asking...

What is the current science based consensus on diet caused DCM in dobermans?

"The current science-based consensus (as of 2026) on diet-caused (nutritional or diet-associated) dilated cardiomyopathy (DCM) in Doberman Pinschers distinguishes it clearly from the breed’s well-established primary/hereditary/genetic DCM.


Doberman DCM Basics


Doberman Pinschers have one of the highest genetic predispositions to primary DCM among dog breeds. This is a progressive, inherited myocardial disease (often linked to specific genetic variants) that typically affects males more, begins in middle to older age, and leads to ventricular dilation, reduced systolic function, arrhythmias, and eventual congestive heart failure or sudden death. Lifetime prevalence can be high (estimates range 20–50% or more in some populations), and it does not reliably reverse with diet changes or taurine supplementation. Screening via echocardiography and Holter monitoring is standard for the breed, with early medical intervention (e.g., pimobendan) used to delay progression.42


Diet-Associated (Nutritional) DCM in Context


Starting around 2018, the FDA and veterinary researchers noted an apparent rise in DCM cases, many involving “non-traditional” diets (often labeled grain-free or “BEG” — boutique, exotic, or grain-free). These diets frequently featured high levels of pulses/legumes (peas, lentils, chickpeas, beans) and sometimes potatoes/sweet potatoes as main ingredients (top 10 on the label). Over 90% of reported cases involved grain-free formulas, and ~93% had peas/lentils.20


Key points on the consensus:

• Association exists, but causality is complex and not fully proven: Multiple peer-reviewed studies show correlations between these diets and DCM-like changes (e.g., increased left ventricular dimensions, reduced fractional shortening/contractility, elevated cardiac biomarkers like troponin I or NT-proBNP). Some dogs (especially subclinical/early cases) show partial or significant improvement in heart function after switching to traditional grain-inclusive diets low in pulses, with or without taurine supplementation. This suggests a reversible “nutritional” or “diet-associated” component in some cases.9
• Not primarily taurine deficiency: Early hypotheses focused on low taurine (an amino acid important for heart muscle), as seen in some breeds like Golden Retrievers or American Cocker Spaniels. However, many affected dogs (including Dobermans) have normal taurine levels. Taurine may play a secondary role in some cases, but it does not explain the majority. Other proposed mechanisms include metabolic effects from high-pulse diets (e.g., altered bile acid excretion, amino acid imbalances, or interference with nutrient bioavailability), and a 2025 study identified a potential urinary biomarker (di-22:6-BMP) linked to phospholipidosis (lipid accumulation in cells) in dogs on high-pulse diets with DCM.13
• Applies to Dobermans too: While primary genetic DCM dominates in Dobermans, diet can act as a contributing or predisposing factor. Studies have included Dobermans in screenings of apparently healthy dogs, showing subtle cardiac changes (e.g., higher troponin) in those eating high-pulse/grain-free diets versus traditional ones. Some Dobermans on implicated diets have shown echocardiographic improvements after diet change, suggesting an overlay of nutritional influence on their genetic baseline. However, diet alone does not cause the classic hereditary form, and genetic DCM does not reverse with diet.1019
• Not limited to “grain-free”: The issue centers more on high inclusion of pulses/legumes than the absence of grains. Some grain-inclusive diets high in peas/lentils have also been implicated. Short-term feeding trials (e.g., 28 days with wrinkled pea diets) have induced early DCM-like changes in non-predisposed breeds, supporting a link, though longer studies in predisposed breeds are ongoing.21
• FDA stance: The investigation (ongoing in a low-key way) found the association complex, potentially involving multiple factors (diet, genetics, individual metabolism). Case reports dropped after 2020 (possibly due to formulation changes by manufacturers or reduced reporting), but the FDA has not declared any specific cause, recalled foods, or banned ingredients. They emphasize it’s not a simple “grain-free = DCM” equation.2
• Ongoing research and nuances: Veterinary cardiologists and nutritionists (e.g., via AKC Canine Health Foundation, Tufts, UC Davis) continue studying mechanisms. Some studies show no major taurine drop or cardiac changes in controlled short-term trials with certain grain-free diets, highlighting that formulation quality, processing, and overall balance matter. Conflicting data exist, and not all high-pulse diets produce issues. However, the weight of evidence from clinical cases, prospective studies, and biomarker work supports caution with high-legume non-traditional diets, especially in at-risk breeds like Dobermans.7

Practical Recommendations from Veterinary Consensus

• For Dobermans: Prioritize genetic/hereditary screening (echo, Holter). Feed a complete-and-balanced diet formulated by a veterinary nutritionist (ideally meeting WSAVA guidelines for transparency in formulation, feeding trials, and manufacturing). Avoid or minimize diets with peas, lentils, chickpeas, or beans as top/main ingredients. Traditional grain-inclusive diets from established brands are generally viewed as lower risk.
• If feeding a suspect diet: Consider switching and monitoring via cardiology workup (echo, biomarkers). Taurine supplementation may help in some cases but is not a cure-all.
• Diet-associated DCM appears more reversible (especially if caught early/subclinical) than primary genetic DCM.

The consensus is that diet can contribute to or exacerbate DCM in Dobermans (via nutritional mechanisms tied to high-pulse ingredients), but it is secondary to the breed’s strong genetic component. The exact “why” (beyond associations) remains under active investigation, with phospholipidosis and other metabolic pathways as emerging clues. Consult a board-certified veterinary cardiologist and/or nutritionist for individualized advice, as individual dogs vary.


If you have details about a specific Doberman’s diet, symptoms, or test results, I can help contextualize further!"

Important disclaimer; I am not suggesting this is accurate, in detail or not. I use AI as a starting point- the summary is helpful but a function of the question asked and the AIs ability to collate only among the public domains of data it has access to...so, if I asked Gemini; supported by Googles data and ai handlers training- I would get a different answer.

I use Grok to quickly find source material that I in turn read myself and apply my own brainpower to decide whats useful.

Then I compare it to trusted expert help and experiential data, opinions, like here. That might give another context or point me to other useful info.

Fun! (Well, if you are a sciencey dog nerd...)

PS: note that on the above linked site there is no "author" name, contact info, and hosting name was anonymized on whois. Not unusual, but also no way to evaluate the maker. (Cue the Twilight Zone music you conspiracy fans...)

The linked info is pretty good, imho, and there are a couple studies missing, maybe since this website was made...

BG1 said:

Found this a few days ago, highly useful compendium of Dobe DCM stuff. No contact info or author info on the About page, or elsewhere but someone did a good job on this site. A couple good links I haven't seen here or elsewhere,
And I think there are a couple more studies/academic groups not yet included
But all in all
its a pretty level headed treatment,
at layman's level understanding...

So kudos and thanks to whomever put this together and hosted it.

About

The Doberman : History & health overview DCM 101 : The basics of Doberman DCM Misinformation : Chronic offenders & popular myths

www.dobermandcm.com

Click to expand...

@BG1 …..thank you Kevin for providing a highly informative and detailed source of information aimed at both the newbie and seasoned Doberman/Dobermann aficionado alike pertaining to the complex issue of DCM within our breed from a Q&A standpoint on a multitude of pertinent issues in need of answers from a layman’s perspective : — i.e. factors to consider prior to potentially becoming a first time Dobe puppy purchaser —> leading to becoming lifelong devotee to our majestic breed that is endowed with three 'givens' of beauty, brains and brawn with the added hope of longevity.

A day into your post and 'traction' regarding viewing/interest appears to be slow for a week-end leisure viewing as indicated by the lacking number of “likes”. Hopefully your effort to share and provide thoughtful insight on a critical issue does not go unoticed and will be discovered on this highly popular and informative Doberman/Dobermann forum where the issue of DCM is ongoing and has been addressed a countless number of times here as well as elsewhere. Sounds like 'I'm blowing smoke up where the sun don't shine' — nope, just 'callin it the way I 'seez-it'.

I accepted your invite to explore the content of the linked-to source and was immediately taken in by the detail provided and like you, impressed by the effort the author — even if it might possibly be Ai sourced — put into generating that DCM relevant source. Allow me to add IMHO a RELIABLE source as per my opinion is hinged on 3 plus decades of active involvement/experience on a near 24/7 day-in day-out commitment to our breed that enables that personal opinion to be 'unapologetically' stated in confidence. Allow me to add on a personal belief and emphasis on “personal” is the Bruce-Lowe-Mendelian concept on line breeding as outlined in Gruenig’s “History of the Dobermann” has served me well where the common related ancestor on both the top and bottom of the pedigree indicated longevity as per research culminating in BFL as can be found on Dobequest for American bred Dobermans or through Euro pedigree data basis.

Having stated such, then that aligns with the your linked anonymous source on the topic of COI — especially the question of low COI and the question of “does it impact the prevalence of DCM?” Please do not misconstrue any implication of a pretentiousness of genetic authority on my part in this highly controversial issue. As stated prior and as always emphasized “ it has served me well” and comes with the caveat not to be considered as 'gospel'.

In the common bond of Dobermans/ Dobermanns …..Mikel

Thanks @MikeP glad to see you posting again.

Yup, still chipping away and trying to learn here; the DOBERMANDCM site has some good explanations on newb level on pedigrees, and a caution on COIs...

and I noticed a couple of sources warned against in one list, couple names disparaged at the other website, so there is maybe a hint as to authorship- old school showline breeder viewpoints, updated as of say 3 years ago.


Btw, I asked about Expected Breeding Values (EBVs) at a germanshepherd webforum and

Like here and at the other forum-

learned its not used much unless you have a lot of data- like at Guide Dogs, Or raising cattle where its used a lot.

So I guess thats another data project to ask breeders if they are contributing their dna/$$$ at UCDavis if they are getting more on dobes, and how much value to breeders from using that tool to compare litters to VGLs info on their large database...

I wonder how many dobe samples VGL actually has now, and if the averages are meaningful- @Rits ?

COI is still vastly important and not to be ignored. For breeds like the original Jack Russel Terrier that a 10% COI is considered high, no, it's not a concern. (The original JR is NOT the Parsons Jack Russel that is AKC version) The average Doberman now being high 30's to mid 40's is a huge concern for multiple reasons. I'd bet of all the lines of Dobermans who carry the most chance of DCM - Euro Show/Pet/Huge Kennel Lines - you'd find very few with COI less than 30. Correlation is not causation, but the more you stack the deck with the same genes, the more likely you'll have genes that double up your chances at getting what you want AND don't want. I wish like hell breeders would post their Embark COI on Dobequest. Nobody should be thinking it's OK to be breeding towards the 50% mark in any breed.

Ravenbird said:

I'd bet of all the lines of Dobermans who carry the most chance of DCM - Euro Show/Pet/Huge Kennel Lines

Click to expand...

That's sort of why we started moving away from Euro lines after Albert. There are so many breeders over there who don't even consider health testing and the results are starting to show through with so many dying way too young. And like you said, so many are way too closely related when they find certain lines who excel at working.

Ravenbird said:

Correlation is not causation, but the more you stack the deck with the same genes, the more likely you'll have genes that double up your chances at getting what you want AND don't want. I wish like hell breeders would post their Embark COI on Dobequest. Nobody should be thinking it's OK to be breeding towards the 50% mark in any breed.

Click to expand...

Absolutely agree here…..ironically, science/unknown factors dispute the logic we share as we would like to hope in the sense that 'stacking the deck ' in our favour as outlined above should weigh in our favour and increase the chances of sidestepping DCM. The evidence is profound that low COI as well as high COI relative to the common ancestor and the breed in general are irrelevant in prediction of occurrence or non-occurrence of DCM. Hence the caveat I alluded to and emphasized in my post pertaining to 3-2 linebreeding as per my example and associated Dobequest BFL as not being 'gospel' — yet it is one I ascribe longevity to in current and past. Nevertheless @BG1 brings good discussion to the table.

I'd be remiss if I neglected to say I appreciate participation/learning/sharing in this premier forum regarding Doberman exclusive content as well as other related working breeds.

In the common bond of Dobermans/Dobermanns …..Mikel

MikeP said:

low COI as well as high COI relative to the common ancestor and the breed in general are irrelevant in prediction of occurrence or non-occurrence of DCM.

Click to expand...

Need to retract the assertion of irrelevant in the sense of 'guarantee'

JanS said:

There are so many breeders over there who don't even consider health testing and the results are starting to show through with so many dying way too young. And like you said, so many are way too closely related when they find certain lines who excel at working.

Click to expand...

It's more the show/pet and those kennels who produce literally hundreds of puppies. True that the European working lines and American show lines have DCM too, but from what I observe it's the BYB mass producers that created the overdone heavy Dobermans that have the highest incidence and at the youngest ages.

MikeP said:

ironically, science/unknown factors dispute the logic we share as we would like to hope in the sense that 'stacking the deck ' in our favour as outlined above should weigh in our favour and increase the chances of sidestepping DCM. The evidence is profound that low COI as well as high COI relative to the common ancestor and the breed in general are irrelevant in prediction of occurrence or non-occurrence of DCM.

Click to expand...

That's one reason why I'm curious about the COI of the general population on Dobequest. I'm curious if dogs that look insanely inbred on paper are not that much different than the ones who have no common ancestors for 4 generations. As I understand it, the COI covers all the genetic commonalities, so may look very different than the pedigree. Seems to me that a Doberman with a 40 COI has a bigger chance at all diseases than one with a 20 COI due to immune deficiencies. I'm no scientist but I think across all animal species inbreeding has been proven to be detrimental to health. It would be so interesting to know the COI of one Doberman pedigree I found on Dobequest that by the 6th generation, one dog appeared in something over half the sire lines. If that COI is similar to a pedigree that has a more diverse pedigree then it would be clear that our dogs are all in trouble due to bottlenecks further back and nothing will ever fix it short of crossing out to other breeds. Also it would be interesting to look at the LOW COI pedigrees and see what dogs are in there that must not have been part of the bottleneck. Most likely BYB dogs, which of the few I know of, seem to be split with some very nice dogs that live with few health problems to those who have extreme health and mental problems.

People here are probably tired of hearing it, but I'm old enough to remember the dogs of the 70's and 80's and they didn't have the mental or physical problems they seem to have today. DCM was there, but it was something dogs got when 10+ years old, same with cancer. I worked at a vet clinic in the 80's and don't recall a single bloat ever in a Doberman. Now it's fairly common. They use to be built with a mildly deep chest and a pretty non-existent front, so that (to me) is a clear cause. They wanted to be with you but didn't whine, didn't have a need to follow you to the bathroom, separation anxiety was not a thing. Everyone these days just says that's a breed thing, and they're right. But it wasn't always like that and we've come to a point of no return.

Ravenbird said:

It's more the show/pet and those kennels who produce literally hundreds of puppies. True that the European working lines and American show lines have DCM too, but from what I observe it's the BYB mass producers that created the overdone heavy Dobermans that have the highest incidence and at the youngest ages.


That's one reason why I'm curious about the COI of the general population on Dobequest. I'm curious if dogs that look insanely inbred on paper are not that much different than the ones who have no common ancestors for 4 generations. As I understand it, the COI covers all the genetic commonalities, so may look very different than the pedigree. Seems to me that a Doberman with a 40 COI has a bigger chance at all diseases than one with a 20 COI due to immune deficiencies. I'm no scientist but I think across all animal species inbreeding has been proven to be detrimental to health. It would be so interesting to know the COI of one Doberman pedigree I found on Dobequest that by the 6th generation, one dog appeared in something over half the sire lines. If that COI is similar to a pedigree that has a more diverse pedigree then it would be clear that our dogs are all in trouble due to bottlenecks further back and nothing will ever fix it short of crossing out to other breeds. Also it would be interesting to look at the LOW COI pedigrees and see what dogs are in there that must not have been part of the bottleneck. Most likely BYB dogs, which of the few I know of, seem to be split with some very nice dogs that live with few health problems to those who have extreme health and mental problems.

People here are probably tired of hearing it, but I'm old enough to remember the dogs of the 70's and 80's and they didn't have the mental or physical problems they seem to have today. DCM was there, but it was something dogs got when 10+ years old, same with cancer. I worked at a vet clinic in the 80's and don't recall a single bloat ever in a Doberman. Now it's fairly common. They use to be built with a mildly deep chest and a pretty non-existent front, so that (to me) is a clear cause. They wanted to be with you but didn't whine, didn't have a need to follow you to the bathroom, separation anxiety was not a thing. Everyone these days just says that's a breed thing, and they're right. But it wasn't always like that and we've come to a point of no return.

Click to expand...

I'm not "tired of hearing it" @Ravenbird

Iirc it was Vic Monteleone who persuaded DPCA to begin the dobequest database longevity project. That today is an invaluable resource but its of course a voluntary submission on longevity and COD, used by primarily US and CAN breeders and its estimated to only contain 5% of all AKC registered dobes.

I notice some odd pushback at times on doberman forums to facts, for example "ad hom" attacks on those who dare to even appear to question the traditional line when presented with science

So far, the best is the Wade, Nuttall, Lu review here:

I'm looking forward to the genetic research being done in U.Utrecht (collab with multiple sources inc Embark), U Mn, UC Favis, of course in its hospital records and Canine Breeding tools like Better Bred.

It always comes down to the data, evem more so today with AI tools; "garbage in, garbage out"
But I'm a fan of discussion and education because that is what drives customer choices.

@MikeP I'm not clear exactly on what is BFL and how it compares in usefulness and outcomes per your preferred model.

Can you provide a good laymans level explanation?

I think the more the informed buyers take up the idea of using best tools, like the vet scientists suggest at DPCA annual seminars, then the more we consumers can support them. Its very expensive doing it right as an ethical preservation breeder vs the commercial breeders and backyard farmers who just reply to the excess demand.

So all we enthusiasts can do is up the discussion- reinforce the basics on health tests like echos, holters at age 2 on, as documented in OFA (see Dr Jerome Bell advocating for this in 2024 DPCA youtube, as its powering cancer reduction in goldens)
And of course mandatory reporting on COD in dobequest.

Btw, while using SuperGrok to help me search for info on LC, etc...
I found this well written explanation with reference to the Wade study.

So, just to be clear- I am not breeder bashing but a fan of ethical preservation science based breeders, and my noob (2 dobes) advice to anyone thinking of buying a great dobe pup is do your homework. This and other forums contsin a wealth of info in archives, now easily searched.

This is the experienced anecdotal with proof point of view, and the more that careful customers discuss "how to" then the more informed become the new customers, who in turn will demand best practices and pay more for quality pups from breeders doing the work right.

BG1 said:

I'm not "tired of hearing it" @Ravenbird

Iirc it was Vic Monteleone who persuaded DPCA to begin the dobequest database longevity project. That today is an invaluable resource but its of course a voluntary submission on longevity and COD, used by primarily US and CAN breeders and its estimated to only contain 5% of all AKC registered dobes.

I notice some odd pushback at times on doberman forums to facts, for example "ad hom" attacks on those who dare to even appear to question the traditional line when presented with science

So far, the best is the Wade, Nuttall, Lu review here:

Comprehensive analysis of geographic and breed-purpose influences on genetic diversity and inherited disease risk in the Doberman dog breed - PMC

Publicly available phenotype data and genotyping array data from two citizen science projects: “Doberman Health Surveys” and “The Doberman Diversity Project” were analyzed to explore relative homozygosity, diversity, and disorder risk according to ...

pmc.ncbi.nlm.nih.gov

I'm looking forward to the genetic research being done in U.Utrecht (collab with multiple sources inc Embark), U Mn, UC Favis, of course in its hospital records and Canine Breeding tools like Better Bred.

It always comes down to the data, evem more so today with AI tools; "garbage in, garbage out"
But I'm a fan of discussion and education because that is what drives customer choices.

@MikeP I'm not clear exactly on what is BFL and how it compares in usefulness and outcomes per your preferred model.

Can you provide a good laymans level explanation?

I think the more the informed buyers take up the idea of using best tools, like the vet scientists suggest at DPCA annual seminars, then the more we consumers can support them. Its very expensive doing it right as an ethical preservation breeder vs the commercial breeders and backyard farmers who just reply to the excess demand.

So all we enthusiasts can do is up the discussion- reinforce the basics on health tests like echos, holters at age 2 on, as documented in OFA (see Dr Jerome Bell advocating for this in 2024 DPCA youtube, as its powering cancer reduction in goldens)
And of course mandatory reporting on COD in dobequest.

Click to expand...

Correction: here is the explanation of what BFL is
I probably was unclear there @MikeP
In my request as to what you like to use for pedigree tools

Here is a bit more on Better Bred as used by UC Davis and note to fellow dog nerds: anyone can get on their email list for updates here:

BG1 said:

@MikeP I'm not clear exactly on what is BFL and how it compares in usefulness and outcomes per your preferred model.

Can you provide a good laymans level explanation?

.

Click to expand...

Simple answer regarding BFL on Dobequest = Bred for Longevity

Whether a breeding model is useful or not, I will always defer to geneticists — which I am not. A COI of 5% or below is within recommended limits to avoid the negative effects of inbreeding or linebreeding, and that COI levels above 10% are where the risks of inbreeding‑related problems begin to rise sharply. The model presented indicates a COI of 6.25 % to help keep the model in an understandable perspective.

With that in mind, circling back to Gruenig’s reference to the Bruce‑Lowe system, the issue becomes clear: Bruce‑Lowe was built on the assumption that you could predict both genotype (speed, stamina, inherent ability) and phenotype (visible traits) by following 3-2 linebreeding pattern. It was never scientifically validated nor based on genetics.

Gruenig’s recommendations were simply the best roadmap available back in the day, long before DNA testing or modern population‑genetics tools existed. No current scientific evidence supports the idea that Bruce‑Lowe’s method could predict genotype or phenotype.

That’s why I always add caveats when discussing it: the historical theory is interesting and has proven for me positive results in current and past Dobermans but modern science does not substantiate that opinion. Hence correlation not equaling causation as expressed in a previous post finds a welcome here in the sense that Gruenig's formula roadmap for better breeding is most likely coincidental and not valid reason that causes the outcome of optimal genetics.

The following is 'window dressing' generated by Microsoft 'CoPilot' telling BFL in better layman terms than what I can provide

On Dobequest, the initials BFL stand for “Bred For Longevity.”
It is a special designation applied to Dobermanns whose pedigrees show multiple long‑lived ancestors and whose own lifespan meets or exceeds the longevity thresholds set by the DPCA Dobequest database.

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What BFL Means in Practical Terms

A dog marked BFL on Dobequest:

• Comes from a pedigree where several ancestors lived significantly longer than the breed average
• Is part of a line that breeders have intentionally selected for extended lifespan
• Often has relatives who lived 10–12+ years, sometimes well beyond
• Signals that the dog may contribute positively to longevity-focused breeding programs


It is not a health guarantee, but it is a meaningful data point when evaluating lines for reduced risk of early mortality, including DCM‑related loss.

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How Dobequest Assigns BFL

Dobequest uses a combination of:

• Verified ages at death
• Pedigree depth (multiple generations)
• Consistency of long-lived relatives


A dog typically receives the BFL tag when both the dog and its close ancestors meet longevity criteria.

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Important Clarifications

• BFL does not mean DCM‑free.
It simply indicates that the line shows above‑average lifespan, which may correlate with lower incidence of early DCM death but cannot be assumed genetically.
• BFL is a phenotype-based marker, not a genotype-based one.
It reflects observed lifespan, not DNA test results.
• Embark COI and BFL are separate metrics.
COI tells you about homozygosity; BFL tells you about observed longevity. They can be used together, but one does not predict the other.

MikeP said:

Simple answer regarding BFL on Dobequest = Bred for Longevity

Whether a breeding model is useful or not, I will always defer to geneticists — which I am not. A COI of 5% or below is within recommended limits to avoid the negative effects of inbreeding or linebreeding, and that COI levels above 10% are where the risks of inbreeding‑related problems begin to rise sharply. The model presented indicates a COI of 6.25 % to help keep the model in an understandable perspective.

Click to expand...

For clarity purposes — the COI 6.25 % cited above pertains to the COI % expressed in the progeny of that single common ancestor and that would be included in the overall composite of 20 to 40 % COI of our beloved breed

MikeP said:

For clarity purposes — the COI 6.25 % cited above pertains to the COI % expressed in the progeny of that single common ancestor and that would be included in the overall composite of 20 to 40 % COI of our beloved breed

Click to expand...

I'm sorry, could you say this another way? I'm confused. If one dog is in the pedigree 5 times then it's 5 x 6.25? If that's the train of thought, what if that same dog appears 3 times in the 3rd generation and 2 times in the 4th gen and 4 more times in the 5th generation for a total of 9 times? Is the % any larger being in the 3rd gen than the 5th?

Ravenbird said:

I'm sorry, could you say this another way? I'm confused. If one dog is in the pedigree 5 times then it's 5 x 6.25? If that's the train of thought, what if that same dog appears 3 times in the 3rd generation and 2 times in the 4th gen and 4 more times in the 5th generation for a total of 9 times? Is the % any larger being in the 3rd gen than the 5th?

Click to expand...

I apologize for creating the confusion. In response to how COI is calculated you can apply Wright's formula which will even add more confusion unless mathematically inclined or approach YouTube and follow the Russian mathematician explain how COI is calculated — neither of which are required in our discussion. Therefore allow me to direct you to a link Inbreeding Calculator

Once having access to the pedigree chart then assign an alphabetical value of A, B, C etc (that represent the Doberman as found on Dobequest) to facilitate entry to the blank boxes. Doing so in this manner eliminates chance of spelling and apostrophe error that would affect the outcome of the result.

The calculator will calculate COI of every alphabetical entry appearing more than one time. The calculator ranges from 4 generations to 12 generations— needless to write 12 generations requires 4096 entries and tedious. The result will appear in a list of individual COIs that when summed up produce the total COI of the pup/dog being researched.

The values arrived at will be based on the number of generations— meaning the deeper the pedigree the greater the COI yet when compared to genetic testing will be less. So, a 6 generation pedigree with several inbred dogs might only show 15 % whereas genetic testing will reveal much more as would a 'deeper dig' in pedigree reveal a slightly higher value.

For genetic diversity then pedigree based COI would appear valueless as it is in error and consequently breeders go to genetic testing for accuracy. My purpose for dabbling in pedigree based COI is not seeking diversity to reduce the certain health related issues plaguing the Doberman yet I find it useful to discover the genetic link to proven performance common ancestors of working lineage with the hope and higher chance that the Higher COI = higher probability of homozygosity across the genome and Lower COI = lower probability of homozygosity.
I reiterate I am not a geneticist nor breeder.

Thanks @MikeP really useful.
I was hoping that screenshotted page on COI on doberdcm would spark some discussion, cuz I'm not entirely sure the point on the concern. Maybe old confusion in forums when retail DNA tests first started generating discussion or bad marketing on "low COI" by bybs, along the lines of "DNA free" just because no markers, found for then DCM1, 2.