Understanding Canine Epilepsy – Part V

A Breeder’s Conumdrum

Key Takeaway: Even breeders with well-planned and carefully researched pairings can produce puppies that develop idiopathic epilepsy. 

Breeders have limited options when it comes to preventing idiopathic epilepsy in any breed.  Primarily because scientists have yet to identify the genetic code associated with idiopathic epilepsy.  And secondarily, because dogs diagnosed with idiopathic epilepsy are rarely identified publicly.  To further complicate matters, polygenic autosomal diseases, such as idiopathic epilepsy, can stay hidden for generations.  Studying pedigrees, using virtual breeding programs to calculate COI and doing genetic testing prior to selecting a sire/dam combination can help reduce the risk of genetic diseases.  But with idiopathic epilepsy there’s currently no way of knowing which dogs are carriers, nor to determine whether a 3-year old dog will develop idiopathic epilepsy when s/he turns 5. 

This being a breeder’s reality, what about the guideline that suggests never breeding any dog whose littermate(s) or whose prior puppies have had seizures?  That’s much easier said than done, and without full transparency of breeders and owners, virtually impossible.  Not every case of canine epilepsy is idiopathic either.  A comprehensive medical evaluation by a neurological specialist, or in cases where a dog has died, a necropsy, is needed to try to determine whether the cause of the seizures that affected a dog was reactive-, structural-, or idiopathic epilepsy…and very few folks pursue either.  So, what’s a breeder of dogs with small populations to do?  Therein lies the conundrum. 

Reminders

  1. There are 3 types of canine epilepsy, with Idiopathic Epilepsy being the most commonly diagnosed.
  2. Canine epilepsy, or seizure disorders, affect all breeds, including mixed breeds. 
  3. No single dog is responsible for idiopathic epilepsy in their progeny.
  4. Currently there is no genetic test that can determine whether a dog carries the genes that cause idiopathic epilepsy.
  5. Every year, in every breed, carriers and affected dogs are unknowingly being bred, creating more carriers and, in some cases, dogs that will develop idiopathic epilepsy.

Fast Facts

  1. Many breeders are either underinformed or uninformed when it comes to the frequency of idiopathic epilepsy in their breed.
  2. Lack of transparency and public dissemination of information about dogs that have had seizures makes it difficult for breeders to know which dogs might be carriers of the genetics associated with idiopathic epilepsy
  3. Inadequate and/or incomplete testing of a dog can result in an incorrect diagnosis of idiopathic epilepsy.
  4. There are risks in breeding young dogs, but there are also risks in waiting until dogs are older.
  5. Removing dogs whose littermates have had seizures from the gene pool is difficult and may actually contribute to implex in the population.

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The primary goal of any sound breeding program is to produce puppies that meet or exceed all requisites of the breed standard, as well as the expectations of the breeder.  Secondarily good breeders also try to prevent the occurrence of undesirable genetic traits…such as yellow coat in Picardy Spaniels, hip/elbow dysplasia, juvenile cataracts, etc.  Most breeders’ ‘homework’ prior to selecting a sire for a dam typically includes an evaluation of basic traits and physical attributes, but rarely is any consideration given to diseases as devastating as idiopathic epilepsy.  It’s not that good breeders don’t care, but rather because idiopathic epilepsy is a rare disease that impacts only ~1% of dogs…and dogs that have seizures are rarely acknowledged openly.  That combination means that many breeders don’t even know that idiopathic epilepsy occurs in their breed.  So, evaluating the risk of producing puppies with-, or creating carriers of the genetics associated with idiopathic epilepsy is rarely a consideration when selecting a sire and a dam for breeding.

Further, not every breeder is well-informed as to the genetic nuances of their breed, nor do they have a long-term breeding plan.  There are plenty of folks who have an outstanding bitch…great demeanor, outstanding prey drive, cooperative huntress, structurally sound, friendly, etc…and they just want a puppy out of that special dog.  But they’ve never bred before, and there’s no breed warden or governing body.  So they do the best they can in terms of selecting a sire…talking to other owners, checking hip ratings of potential sires, looking into hunt test scores, and maybe even reviewing COIs while perusing pedigrees.  That’s all helpful, but they simply don’t know what they don’t know, which can easily lead to breeding a carrier to another carrier of any undesirable recessive genetic trait…be it as benign as coat color or as catastrophic as idiopathic epilepsy.  Without being connected to someone who’s been ‘in the breed’ long enough to know about potential genetic problems, these first-time or infrequent breeders do their best, hoping everything is going to work…but hope is not a strategy.

Beyond knowledge and connections there’s another set of circumstances that increases the risk of recessive diseases and traits showing up in a litter and continuing in bloodlines…time and money.  Even with complete 10-generation pedigrees and full disclosure regarding the health of prior generations, a breeder must still be able to navigate the logistics of breeding the ‘perfect sire’ to his or her bitch.  Because if the ‘perfect sire’ is 1,200 miles away…2,000 kilometers…as was the case for Brick Church Kennel’s Picardy Spaniel B-litter, it takes a lot of time and money to get the sire and dam together.  Not everyone has that level of commitment to the breed, a flexible enough work schedule, nor the financial wherewithal to make that breeding a reality.  So in many cases the ‘best sire’ may be passed over in favor of the nearest available stud.  It happens in every breed.  But too many people choosing sires based on convenience and low-cost can accelerate implex.  It’s not wrong, but neither is it right, as those matings typically do not help the long-term health and viability of the breed.  Especially a rare breed with a small population.

There are a few breeding practices that also make it difficult to prevent genetic diseases like idiopathic epilepsy from occurring in a litter and from continuing on in a breed: breeding young dogs, inbreeding and popular sire syndrome.  We’ve discussed inbreeding and popular sire syndrome in Part IV of this series.  Regarding breeding young dogs, the rationale many veterinarians give for that practice is that ‘their eggs and sperm will never be any better.’  As a female ages the odds of her conceiving and having a healthy litter decrease while the risk of genetic mutations, which could cause genetic diseases, increases.  It’s somewhat similar in males, the quality of semen…morphology, morbidity, and motility…decreases as he ages, which can also lead to genetic mutations.  Breeding dogs when they are 2-3 years old means that they are old enough to have passed hunt tests and hunted a couple of seasons.  They’re also old enough to have had their hips, elbows, structure and bite evaluated.  And by that age you’ve also had enough time to judge qualitative traits such as cooperation, demeanor, personality, etc.  The downside of breeding young dogs is that a breeder has no idea whether that healthy, beautiful hunter or huntress that is bred at age 3 will develop idiopathic epilepsy at age 5. 

Many folks suggest breeders rely on a guideline that recommends never breeding any dog whose littermate(s) or whose progeny have had seizures to help minimize the risk of idiopathic epilepsy.  In theory that makes sense, but in practice it’s difficult, and sometimes it’s not possible.  And in breeds with small populations it might not be practical.  There are a couple reasons for this.    

  1. Without full transparency about dogs that have seizures, a breeder or owner of a stud dog may not know that their dog is related to another that has some form of canine epilepsy.
  2. Without extensive testing and examination by a neurological specialist it is virtually impossible to determine whether the seizures are truly due to idiopathic epilepsy – it could be structural or reactive.
  3. Meiosis, the process by which chromosomes divide to produce sperm and eggs, can result in a litter of 8 pups where one puppy will be affected by idiopathic epilepsy, 2 pups carry half of the genes associated with idiopathic epilepsy, and the other 4 aren’t even be carriers.

These realities bring up difficult questions.  Should an entire litter of dogs be banned from breeding because one dog ate something that caused seizures?  Or, because one dog had an adverse reaction to an oral flea/tick medication?  Or because one dog had a brain tumor?  My Gram would say “don’t throw out the good with the bad.”  And that brings up another difficult question.  Is eliminating every dog that might be a carrier from the breeding pool because they ‘might’ be a carrier justified?  If so, how much does that reduce the breeding pool?  And if the breeding pool is reduced, how then do breeders avoid contributing to implex in the population?  Especially in a breed with a small population like Picardy Spaniels.

Thus the conundrum…how can a breeder avoid breeding a carrier to a carrier in a breed with a small population?   Do breeders need to accept idiopathic epilepsy as an unavoidable risk of breeding?  Should every breeder consider idiopathic epilepsy a rare disease that no one can prevent?  Is it just something that’s going to happen eventually in every breed and if a breeder is unlucky s/he may end up producing a puppy with idiopathic epilepsy? Or is there another way?  We’ll share some suggested breeding practices that may help reduce the incidence of idiopathic epilepsy…as well as other genetic diseases…in Part VI, the final installment of this series.

Part VI: Improving Breeding Practices, will be posted on 06Jul26

Unfortunately we’ve had epilepsy in a litter of Picardy Spaniel puppies we’ve whelped, which is why we’ve decided to share the information we’ve uncovered about canine epilepsy. The publication of this series may be uncomfortable for some folks, but we are more concerned with the long-term health of our breed than about being politically correct. Our goal with this series on canine epilepsy is twofold. 

  • First, we want to share the information we’ve uncovered about canine epilepsy.  Had we known a few years ago what we know now about canine epilepsy we would have made some different decisions with our dogs.  Hopefully this series will help owners and breeders make more informed decisions about breeding and about the health of their dogs.
  • Second, we want to figure out how best to minimize the risk of canine epilepsy in the Picardy Spaniel going forward.  To try and achieve this goal we’re working with one of our puppy owners who is a biostatistician for a large US-based health care company.  There is also a group in Europe that is working with a canine geneticist in Germany.  We plan to share our data with the European group once we have run all the statistics and completed the pedigree modeling.

If you want to help, please email us directly if you own, have bred or otherwise know of a Picardy Spaniel that has epilepsy or has had seizures.  Thank you in advance for your help.  We not only need to be open and transparent about how great the Picardy Spaniel is, but also about any and all health issues if we are going to be good stewards of the breed.  Our children, grand children, great grand children, etc. should be able to enjoy healthy Picardy Spaniels long after we’ve crossed the rainbow bridge.

Please feel free to email questions, comments and/or the names of any Picardy Spaniel affected by seizures to ricplath@gmail.com.

Part IV
Part VI

Reference Material Sourced From:

  • University of Missouri Veterinary Health Center
  • National Institute of Health (NIH)
  • Cornell University College of Veterinary Medicine
  • Tuft’s Canine and Feline Breeding Conference
  • University of California – Davis
  • Royal Veterinary College
  • University of Manchester
  • University of Helsinki
  • University of Minnesota College of Veterinary Medicine
  • Institute of Canine Biology
  • My Epileptic Pet – Domes Pharma
  • WebMd
  • Genetics for Dog Breeders – Hutt
  • Veterinary Partner
  • Frontiers in Veterinary Science
  • Double Helix Network News

Ric, Ellen and their Picardy Pack live in Westby, WI.  A lifelong hunter, Ric has trained and hunted Small Munsterlanders, Gordon Setters, and for the past 10 years Picardy Spaniels.  Ellen has an extensive background in animal genetics and a PhD in Reproductive Physiology.  She bred and trained Greater Swiss Mountain Dogs prior to Picardy Spaniels.