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The Dalmatian Backcross Project

The Dalmatian Backcross Project. A Presentation to The Board of The Dalmatian Club of America April 29, 2006 Fort Mitchell, Kentucky Robert Schaible, Ph.D. * Mary-Lynn Jensen, Ph.D. * Karen Rochin Stocklore Dalmatians Woodwynd Dalmatians SunRunner Dalmatians.

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The Dalmatian Backcross Project

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  1. The Dalmatian Backcross Project A Presentation to The Board of The Dalmatian Club of America April 29, 2006 Fort Mitchell, Kentucky Robert Schaible, Ph.D. * Mary-Lynn Jensen, Ph.D. * Karen Rochin Stocklore Dalmatians Woodwynd Dalmatians SunRunner Dalmatians

  2. There is nothing more powerful than an idea whose time has come. - Victor Hugo

  3. Why Has The Time Come? • The extent and seriousness of urate stone disease in the breed is undeniable. • Even with careful attention to diet and management, too many Dals need veterinary intervention for urinary blockage. • Treatment is painful for the dogs and very expensive for the owners. • It is not uncommon for owners and veterinarians to choose euthanasia rather than surgery and a lifetime of daily medication, prescription diet and constant monitoring.

  4. Why Now? • Twenty years ago, it was believed that urate stone disease affected only a small number of middle aged male Dalmatians. • Recent research by Dr. Danika Bannasch, at University of California Davis, and DCA Health Committee veterinary liaison, Dr. Suzanne Hughes, has shown that many Dalmatian males, and even females, have stones or debris in their bladders at any given time. This is true of many Dals who have shown no outward signs of stone formation. • The level of Low/Normal Uric Acid (LUA) potentially breeding Dals was at a critically low number such if something wasn’t done now, LUA Dalmatian might have become extinct.

  5. Brief History of The Project • The Dalmatian-Pointer Backcross Project was started by Robert Schaible, Ph.D. a medical geneticist at the University of Indiana. • The goal was to breed dogs of Dalmatian type and temperament, but with low (normal) uric acid levels. • The theory was that the low uric acid dogs would be free from the predisposition to urate calculi.

  6. Brief History of The Project • In 1974, a single male Champion Pointer was bred to a female Dalmatian. One bitch from that litter was then bred to a Dalmatian. • Dr. Schaible continued backcrossing to purebred Dals, selecting for Dalmatian type and low uric acid. • By the fifth generation, the puppies had 31 Dalmatians and 1 Pointer in their pedigree. • In 1981, the American Kennel Club agreed to register two of the fifth-generation the pups, a male and a female.

  7. Brief History of The Project • The DCA Board of Directors had supported this decision, but the registration became a very controversial issue among the Club membership. • A DCA membership vote opposed the registration and AKC was notified. AKC let registrations of the original two dogs stand, but rescinded the right for any of their offspring to be registered. • Since that time, Dr. Schaible has continued this project almost singlehandly.

  8. A Simple Genetic Explanation • The mode of inheritance for uric acid levels in a Dalmatian is like that for color. It is controlled by a single recessive gene (u). • Unfortunately, while selecting for spotting pattern, early Dalmatian breeders may have inadvertently selected for the high uric acid trait, creating a breed with a uu genetic pattern. • Common sense would dictate that this would be easily remedied by breeding to a dog with the UU or Uu genetic pattern to eliminate the uu (or high uric acid) dogs. • However, to the best of our knowledge, there are noDalmatians who carry the UU or Uu genetic pattern other than the Backcross Dalmatians.

  9. How It Works? u u u uu uu With current, high uric acid Dalmatian breeding (uu x uu), all pups have high uric acid and are homozygous for the recessive gene. This is like breeding two liver Dals. u uu uu

  10. How It Works? U u When breeding a heterozygous low uric acid Dal, who still carries the high uric acid trait, to a high uric acid Dal, half of pups will have high uric acid, and half will have normal uric acid; but they will carry the high uric acid gene. This is like breeding a liver Dal with a liver-factored black Dal. u Uu uu u Uu uu The Uu dogs will be LUA Dalmatians

  11. How It Works? U U When breeding a homozygous low uric acid Dal to a high uric acid Dal, all of the pups will have normal uric acid levels, but will still carry the high uric acid gene. This is like breeding a pure for black Dal to a liver Dal. u Uu Uu u Uu Uu These pups will all be LUA Dalmatians. The pointer will appear in their extended pedigree ONE time. However in the pedigree of the UU homozygous low uric acid parent, the pointer will appear in the extended pedigree TWO times.

  12. How Do We Know? • The current DNA test can distinguish HUA Dals from LUA Dals and UU Dals from Uu LUA Dals. • DNA testing is done using removed dewclaws. By using the tissue that would normally be discarded there is no need to subject pups to a blood draw or cheek swabs. • Currently, the DNA test is followed with a urinalysis to verify that the pups identified as LUA do indeed have low levels of uric acid in their urine and the HUA pups have high levels. • Two urine samples from each pup are tested. Technicians who process the urine samples work in a completely different lab from those that do the DNA testing and have no knowledge of the prior test results.

  13. How Do We Know? • Additionally, Dr. Dannika Bannasch and Dr. Noa Safra, at UC Davis believe that they are very close to identifying the gene that causes the metabolic defect. • Current DNA testing is funded by Dr Bannasch’s research. Once the test is perfected, the cost is expected to be about $80 per pup, which is similar to the VetGen DNA test for color. • Both the DNA test and the urinalysis to confirm the DNA test are done well before the time the pups are placed enabling knowledgeable decisions as to their possible breeding future to be made.

  14. Current Status of the Project • Total Number of Backcross Pups born in 2005: U-GrCh Stocklore Forrest Can O’Pee x Robinwood Glamour Girl (All BAER Bi) LUA: 1 male patched, 2 females (1 patch)HUA: 1 male, 2 femalesU-Ch Stocklore Top Spot x Robinwood Hanna DoorightLUA: 2 males (1 deaf), 3 females (2 patches)HUA: 2 males (2 patches), 1 female (uni w/ 1 blue eye) U-Ch Stocklore Top Spot x Ch Aberdeen’s Twlight Time (All BAER Bi) 5 LUA: 1male, 4 females 3 HUA: 1 male, 2 females • Backcross hearing numbers appear to be consistent with “regular” Dalmatian hearing ratios. • Key dogs in the backcross pedigrees have lived to ripe old ages.

  15. Show Me The Spots!

  16. First Generation Hybrid

  17. Stocklore Stipples - 5th generation, accepted into AKC registry

  18. RFBCN Blackeyed Susandaughter of Stipples

  19. RFBCN Lidgates Triever Watson CD Son of Blackeyed Susan

  20. RFBCN Helen

  21. Tucker, Daisy & Cinnamon Stipples (daughter of RFBCN Blackeyed Susan & Ch Sunspot’s Rambler Ottomatic CDX)

  22. Snowdog’s Swiss Forrest Tobler (bred to Ch Forrest Douglas Fur)

  23. Stocklore Squire of Britannia Son of Stocklore Jacob’s Ladder

  24. Stocklore Budgette Buster Daughter of Squire

  25. U-Ch Stocklore TopSpot Son of Budgette

  26. U-GrCh Stocklore Forrest Can O’PeeSon of Budgette UKC/AKC Judge Jeffrey Pepper

  27. "A" Litter born 8/12/05Sire: UKC Ch Stocklore Top SpotDam: Ch Aberdeen's Twilight Time Missing photos of 1 LUA male pup

  28. BonnieU-GrC Topper x AKC CH Twyla

  29. Bonnie

  30. Bonnie

  31. Bonnie

  32. Bonnie & Friend

  33. Bonnie

  34. LaylaU-GrCh Topper x AKC Ch Twyla

  35. Layla & AKC Ch Aberdeen Time For Jessie (littersister to Layla’s mother, Twyla)

  36. Aberdeen Seeing The Forrest U-Ch Opie x Vanna

  37. What Could Happen Next? • A formal DCA Board recommendation to the membership that discussion on the backcross Dal project be reopened. • The opportunity to inform the entire DCA membership with ongoing information about the backcross project through The Spotter. • Formation of a DCA Backcross Study Group • DCA member discussion/vote on the Backcross Project • DCA recommendation to lift the AKC hold on backcross registrations • Provide the OPTION for breeders to incorporate AKC registered, LUA dogs into their breeding programs should they choose to • To someday lift the specter of urate stone formation from our breed.

  38. In Closing There is nothing like dream to create the future. Utopia today, flesh and blood tomorrow. - Victor Hugo

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