Breeding Dogs & Screening for Genetic Health Issues

Good Question, Kayla. Thanks for Asking!

Lately I've been getting some comments and questions about DNA and Health Testing on my blog and social media. While I do test my dogs for genetic defects, both through PennHip screenings for Hip Dysplasia, as well as DNA testing, in no way do I consider myself an expert on the topic. Therefore I wasn't planning to write about the subject. All of my dogs' DNA and PennHip results are listed prominently on their individual pages on my website. So if someone wants to know about the health of my dogs and the breeding decisions I have made based on those results the info is very easy to find. But if someone was asking for an explanation of health testing in general then I felt that they could find a better resource than me.

However I feel strongly that anyone with a social media following at all should take that responsibility very seriously. If they are someone with any kind of expertise or credibility in a field they should strive to always use their platform for the good of others, whether those "others" are humans or animals. In this case answering these questions is for the good of the Maremma Sheepdog breed and the people who love and utilize the dogs. People need  responsible, educated and articulate people to go to for information and education about these amazing dogs. People like Cindy Benson, of Benson Maremmas - published author of a Maremma Sheepdog Training Manual (available on Amazon) and a certified dog trainer (KPA CTP) who specializes in Maremmas. Platforms like YouTube,  and TikTok have their place but they are usually heavy on entertainment instead of education. And sadly some of them rely on clickbait, controversy and manipulating people's emotions to make money. Even innocuous ones are no substitute for true education, or for professionals who have long-term and wide experience with the breed. Ethical Maremma breeders and certified dog trainers experienced with Maremmas are who people should go to for trustworthy advice about Maremmas.

As a Maremma Sheepdog Club of America Code of Ethics breeder, dairy goat breeder who utilized Maremmas to keep her animals safe, a business owner, LGD trainer and admin of multiple Maremma related social media pages or groups, I do feel I have a responsibility (and honor) to educate people about the breed I love, breed, rely on and work with daily on my farm. So though I'm no expert on the subject I'll give it a shot!

If you would like to DNA test your own dog or learn more about DNA testing go here:

Embark Vet

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To Illustrate how to interpret DNA tests and use it to make breeding decisions I'll use one of my own dogs, and her test results through Embark.

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Here's my dog, with 3 of her puppies. Her name is Sky Island's Gianna. 
​She's a beautiful dog, isn't she?

Now for a little background info on Gianna. Gianna was imported en utero by a MSCA Code of Ethics breeder who imported her dam, a Finnish champion, while she (the dog, not the breeder) was pregnant. Gianna's sire is an Italian champion so Gianna has all imported lines, bringing much needed new genetics to the breed. Gianna will be 4 years old in October 2022 and she has had two litters, of 7 and 13 puppies. If you would like to see Gianna's pedigree, full health test results (PennHip and Embark results) and other info you can click on the button below and go to her page. Below that is a screenshot her Embark profile:

Sky Island's Gianna

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And now Gianna's Embark Health Summary results:

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Oh my, Gianna has positive results for DCM2 and ALT Activity! Yikes! This looks bad. Really bad. I should probably spay her. It's the responsible thing to do, right? Or is it? Hmmm...maybe I should click on the next screen and read what these results actually mean before I call my vet. ​

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First the DCM2 results. Let's do some reading:

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Wait, Embark themselves say that Gianna is not likely to be at risk for developing the disease and that DCM is not known to be common in Maremmas, nor should these results be the primary factor in breeding decisions. The disease is most common in Dobermans, which are not at all closely related to Maremmas. And even in Dobermans it is not recommended to remove all dogs with one or even two variants (Gianna only has one) from the gene pool. Why? Because by removing dogs from the gene pool of an already small breed you increase inbreeding, which in turn increases the risk of other genetic defects. Defects we may not even have a test for yet.

I did a quick google search on how many registered Dobermans are in the USA and got 39,000. Now I'm no expert but I'm pretty sure there aren't 39,000 registered Maremma Sheepdogs in the USA.

We aren't counting unregistered dogs because without registration and "official" pedigrees from an accepted registry you can't 100% prove what breed a dog is, nor who his parents are, even with DNA testing. If you could then all registries would accept DNA tested dogs into their gene pool. As far as I know, no reputable registry does, including the Maremma Sheepdog Club of America.

In fact, there was a big push to add DNA tested dogs to the MSCA stud book earlier this year and it was not approved because, according to those who did the research, the science doesn't support it.  So though I have nothing against unregistered dogs, owning 4 of them myself, they aren't really relevant to this discussion. You can certainly DNA test an unregistered dog to determine if they carry genetic defects but without actually knowing where they came from through a registry sanctioned pedigree you can't do a lot with the information, since you don't officially know where those defects, if any are present, came from. 

So registered Maremmas in the United States are a much smaller breed than Dobermans, without a known predisposition to the disease and with a very specialized purpose as working LGD's. So would it be "the right thing to do" for me to remove a dog from my breeding program that has a lot of other great qualifications (stellar hip scores, correct conformation, working ability as a LGD, diverse genetics from imported lines) because she carries one gene for a disease that Maremmas aren't known to be at risk for and for which the testing company says it's not an important factor in breeding decisions? In my opinion that would be a very stupid reason to remove her from my breeding program. I prefer to use science and proven results (how my dogs perform as LGD's) over emotion when making breeding decisions.
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​So no, I won't be spaying Gianna over her DCM2 results.

Now lets look at the ALT Activity:

Oh no, Gianna inherited this "ALT Activity variant! That's bad, really bad! Call the vet, we better spay her TODAY! Right? It's the right thing to do, isn't it? Or is it? Hmmm... I better read the next screen and see what these results actually mean. 

Wait, what does that say? "This genetic test can be used as a clinical tool by veterinarians." "This genetic test does not diagnose a disease." "Dogs with one or two copies of this variant may have an ALT value that is low or on the low end of the normal reference range."

Wait what?! This only means that Gianna's "normal" ALT range is lower than average, but that it's still HER "normal" and is not at all indicative of any disease? Just like a person can have a resting heart rate that's higher or lower than the "average" person their age, or their temperature can naturally run higher or lower than 98.6, or any number of factors can be above or below "average" in humans or animals. And actually the results say it "may be" lower than normal, not even that it is. Hmmm...

Let's not forget what "average" means. You can't have "average" anything without some things in that category being above or below average. That's how you get average! And below or above "average" isn't always bad.

Now if someone else chooses to not breed a dog because their ALT activity  "may be low normal", which is still perfectly normal for them but not "average", and not indicative of a disease, then that's their choice to make. Maybe they only want "average" dogs in their breeding program. That's ok. But again, I prefer to base my breeding decision on more important factors, like science.

So no, I won't be spaying Gianna because of her "Low Normal" ALT Activity.

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So What Health Test Will I use First to Base my Breeding Decisions on?

Now let's look at a health condition that really is a problem with Maremma Sheepdogs - Hip Dysplasia. Maremmas are a giant breed of dog that grows fast and can mature in excess of 100 lbs. They are also hard working dogs, bred to guard livestock in a variety of terrains. They need sound hips to have long, productive, pain free lives as LGD's. A LGD can't fight off predators or even navigate the outdoor terrain they may be guarding if they have crippling pain from arthritis. So while DNA testing is a great tool, smart Maremma breeders (or breeders of any large breed dog) will first take a look at the dog's hips to rule them in or out for breeding. Good scores of the parents' doesn't guarantee their puppies won't get hip dysplasia but its still a very important diagnostic tool. 

In fact, hip testing is the ONLY health test required to be a MSCA Code of Ethics breeder. DNA testing isn't required. Why? Because most of the things you DNA test for aren't a big concern for Maremmas. As far as I know only one or two other MSCA Maremma breeders besides myself DNA test their dogs.

Now it's not that I think DNA testing isn't a valuable tool for the breed. Of course not. Anything breeders can do to improve the breed is a good thing and that's why I started DNA testing my dogs. It's not very expensive and it gives me useful information to make breeding decisions. And if more breeders tested we would have a bigger database to compare our dogs to, and would really see the big picture for the breed. So I hope more Maremma breeders do start DNA testing and I hope the MSCA starts to educate their members on the benefits and limitations of DNA testing. Maybe one of the BOD members could write an article in the MSCA newsletter. 🤔

This may offend some people but, in my opinion, DNA testing Maremmas (or any large breed dog) without also doing hip screening is often times nothing more than virtue signaling and pretending to be ethical without putting your money where your mouth is. I see breeders listing their dogs (all breeds, not specifically Maremmas) as "health tested" with no hip testing. Often times that's just tricking the uneducated potential customers, IMO. (Someone I know bought a Great Pyrenees puppy and proudly told me it was from health tested parents. I checked the website. No hip testing whatsoever. Let's hope that puppy doesn't end up with Hip Dysplasia.) Anyone can afford the $100 DNA test and it's quick and easy to do. Add a check in the "health tested" box. But if you really want to prove your dogs are sound and healthy to breed how about forking over $600-700 for a PennHip exam, or even $300-400 for an OFA hip exam? (PennHip is proven to be more reliable and scientific so that's what we use, but OFA is acceptable if done right and certainly better than no hip testing at all.) That will prove something of real value to the breed. And that, along with the DNA testing, would be even better.

So let's look at Gianna's PennHip Scores:

Gianna's Distraction Index is 0.32 R and 0.32 L. There's no evidence for osteoarthritis and no cavitation.

The breed average is .40 (lower is better) and to qualify as a MSCA Code of Ethics breeder (see below) dogs must have a score of less than 0.51.

This means that Gianna has outstanding PennHip scores. And she is much more likely to pass on those good hips to her puppies than she is to pass on DCM, which isn't known to be a problem in Maremmas or low ALT activity, which isn't even a genetic defect at all. 

MSCA Code of Ethics Testing Requirements

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The Limitations of DNA Testing:

DNA testing is a good thing. I'm not saying it isn't or I wouldn't have spent the money to test my dogs. I plan to continue DNA testing my breeding dogs and learning more about how to utilize the information. But DNA testing has its limitations and needs to be used wisely and put in perspective. In my opinion breeders who make their breeding decisions only based on DNA results are throwing the puppies out with the bathwater and potentially harming the breed. As I've said, there are a lot of factors to consider when breeding dogs. Below is a little more info on that topic.
​(The ICB is a GREAT scientific resource for breeders, btw.)

• Why DNA Tests Won't Make Dogs Healthier - Institute of Canine Biology
• What Does "Health Tested" Really Mean? - Institute of Canine Biology

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So What Else Should I Base My Breeding Decisions On?

When breeding any breed of dog there are a lot of factors to consider and focusing too much on a few traits while ignoring others can cause many problems, not just in our own breeding program but long term, with the breed. If this is true of companion dogs it's especially true of working Livestock Guardian Dogs, who are responsible for the safety and well being and the very lives of other creatures. Then consider a breed such as the Maremma Sheepdog, that has a much smaller gene pool than a lot of breeds and it's a big responsibility to breed these dogs. Breeders must be discerning, wise and able to keep their long term goals in mind when breeding Maremmas. They should always be evaluating their program as well as seeking out new information (through reading, taking dog breeding and training courses and having discussions with reputable experts in the breed or the dog breeding world, in general) that will help them do the best job possible with their dogs.

As far as making individual breeding stock selections some of the things to consider are temperament, working ability, pedigrees, Coefficient of Inbreeding (kept as low as possible), correct conformation, sound hips and other health testing.

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So How Does Gianna Measure Up?

• Temperament - Gianna is a bit dominant with some other female dogs (not uncommon in the breed) but otherwise has a good temperament. She's not aggressive with people and is a well mannered, sweet dog.
• Working ability - Gianna is a good LGD. She's good with goats and excellent with chickens, which many LGD's struggle with. She's strong, athletic and fearless and there's no doubt in my mind that she would kill a predator if she had to. If I were a coyote I would not want to meet Gianna in the dark!
• Pedigree - both of Gianna's parents are European dogs so her lines are very diverse from what's generally available in the US.
• Coefficient of Inbreeding - Gianna's pedigree based COI is 0.00. Her DNA tested COI is 11%, with high diversity. I'll be perfectly honest here and admit that I am still learning about the difference between pedigree based COI and DNA COI, and what it all means. But basically Maremmas as a breed have a very small gene pool so a lot of dogs that aren't closely related by pedigree will still have higher COI's based on DNA and can still share more DNA with dogs that they aren't actually related to. Meaning that if I found out that one of my other dogs shared a high percentage of Gianna's DNA it's not because that dog is her cousin or something. It's just that they have more ancestors in common way back in their background than would appear by reading their pedigrees. Since no one did a DNA test on Gianna and her "cousin" before I bought Gianna there would have been no way for Gianna's breeder to know they were so closely related, since the pedigrees we have don't go that far back. It might be a shock to find out such news but it's certainly not some deep, dark secret and no one did anything wrong. It's just another result of having such a small gene pool to work with. And that's why DNA testing for COI is a useful tool. (Of course you have to have an "official" MSCA pedigree to even begin to tell if two dogs are related or not, which is one reason why I won't allow anyone to breed one of my registered dogs to their unregistered dogs, since they can't prove their dog is who they say he is. If I bred Gianna to an unregistered dog it would be entirely possible that he was her REAL cousin! 😳) I plan to do a lot more research on DNA COI's and how that all works, but either way, Gianna brings a lot of diversity to my program and the breed in America in general.
• Correct Conformation - Gianna has stellar conformation and, IMO, is one of my most correct and beautiful dogs. She's a large, impressive dog and of a good size for guarding against any sized predators and for easy whelping. She whelped 13 puppies in her last litter with no problems whatsoever. And all the puppies survived, too. Easy whelpers that produce healthy, strong puppies is worth a lot in a breeding dog.
• Sound Hips - Gianna had excellent PennHip scores, well below the breed average and even further below the maximum score for Code of Ethics dogs. I will most certainly consider those amazing hips above some other, less relevant test results.
• Other Health Testing - Gianna's Embark Results, despite having two variants checked on her profile, are still not concerning. The ALT Activity is a clinical tool only and the DCM2 is not considered breed relevant or a big risk factor.

So when I weigh all the traits Gianna has going for her against the small things that are less than "clone perfect" it's an easy call. Gianna stays in my breeding program, to help improve future generations of these amazing Livestock Guardian Dogs.

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So What Are My Thoughts About Genetic Health Testing and Dog Breeding?

These are my thoughts. No dog is perfect. They all have faults of one kind or another and they all have strengths. Wise breeders will weigh the pros and cons of their dogs and decide if they bring enough value to their breeding program and to the breed in general to be included. If the answer is yes then they will match that dog with a mate who is likely to improve the areas that aren't quite perfect, or to compliment them well. It's the same with breeding any animal - goats, horses, cattle, cats, whatever. We are working with living, naturally created animals here, not laboratory grown clones. It's as much art as science. We will make mistakes. Things don't always turn out how we planned. There's no shame in that as long as we learn from those mistakes so that we can do better the next time. The best breeder in the world will still never achieve breeding all "perfect" dogs. But if they are smart enough and dedicated enough to continue to learn and research and to look beyond the surface (and to read the fine print on the DNA test) then they just might achieve breeding "almost perfect" dogs. Which is still a pretty worthy goal.

​I know what I will do with the time that is given to me. I'm going to breed the best "almost perfect" Maremma Sheepdogs I can. What about you?

 “All we have to decide is what to do with the time that is given us.” 
― J.R.R. Tolkien, The Fellowship of the Ring