A Great Dane and a Miniature Horse, North Carolina.
As many as one in four harlequin Great Danes may be born deaf and put to sleep -- something a professional breeder might "take care of" by simply slipping a new-born puppy into the freezer.
And what of the horse? Just imagine if we did to horses what we have done to German Shepherds.
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Harlequins have some interesting genetic basis. It is a type of blue merle dane with what is called a "clearing" factor that makes the blue coloration white. If you breed two dogs with the blue merle gene and together, the puppies will die in utero. That's why the harlequin color doesn't breed true.
ReplyDeleteAnd that explains why a breed of pinscher went extinct. In Germany in the 1880, there was an attempt breed a line of merle miniature pinschers. This would be a separate breed from the miniature and German pinscher breeds. The preferred color was the merle with the clearing factor, although other colors of merle were allowed in the breeding program (and many of the dogs were blue and red merle). But the goal was to produce as many harlequins as possible.
But if all you have in your line is merle, and what you're trying to breed generally dies in utero and the ones that survive have lots of health problems, the breed isn't going to last long. It became a strain of nothing more than double merles.
The breed was called the Harlekinpinscher: http://www.devrolijkeviervoeters.org/images/harlekijnpinscher03a.jpg
The original dogs most likely came from cross breeding with dapple miniature dachshunds. Miniature pinschers and miniature smooth dachshunds are very similar in color and behavior for a reason. They were often crossbred. Dachshunds also originally had some various forms of white, which could have been the clearing factor.
Some people are trying to breed merle min pins and call them harlequin pinschers. They are using blue merle rat terriers:
http://amyslittleminpins.com/HarlequinPinschers.html
None of these dogs are actually harlequin. They are all merles.
Just like the "English white terrier," breeding for this coloration wound up hurting the breed. The last of the Harlekinpinschers is believed to have die in 1930. The dogs were thought of as very unhealthy, and no one wanted one.
Links to support the Great Dane issue?
ReplyDeleteWhite boxers could stop being born if they would just stop breeding for flashy marking in brindle and fawn boxers. These flashy markings do not breed true. All flashies carry the gene for solid white. If you breed two flashies together, statistically, you will get 50 percent flashies (which are show ring eye candy), 25 percent solid brindles or fawns, and 25 percent whites.
ReplyDeletePeople go on and on about how white boxers have health problems-- and they do-- but they don't ever seem to condemn what creates them. It is almost never people breeding a line of solid white boxer. It actually comes from breeding flashy markings in the show ring.
I have often repeated (and have been savagely attacked by people with no brains) that white boxers are just as healthy as the other colors. It is estimated that 30 percent of these dogs are either deaf in one ear or are totally deaf in this country.
They are fools.
They aren't as bad as the people who want to breed "white" dobermans. The gene that makes dobermans white isn't actually one that we should ever breed for! It's the albino gene! The dogs have sensitivity to light. Many are horribly sunburned in even modest sunlight.
http://whitedobes.doberinfo.com/
People need to think long and hard about color. Unusual colors are beguiling to us. We're a visual species. In fact, I have a breed that was selected mostly for its color.
But some of these colors are associated with real health deficits. The dogs don't care what color they are. They just want to be healthy and comfortable.
Hurricane Deck see >>
ReplyDeletehttp://5z8.info/myspace-of-sex_k2z9c_girlsgonewildpart1.wmv
or just Google; lots of data on deafness and harlequins.
P
Although overbreeding mini horses results in too much dwarfism, at least the mini horse in this picture does not have major conformation problems. I'd rather just find a nice sheltland anyway, but the larger minis bred for good conformation and ability are fine with me (see AZ Mini Mystique, a mini horse drill driving team. They do real work!) But the push for smaller and smaller and the resulting dwarfs is as creepy as the great danes. As retrieverman says, the dogs don't care what color, they just want to be comfy and happy. Why don't people want the same for their specialty breed -whatever the species?
ReplyDeleteSorry! I should have been more specific - the part about breeders putting them to sleep.
ReplyDeleteI have Ratties - and we have just now seeing the effects of extreme piebalding, i.e. dogs with piebald parents being born completely white due to that progression. One of the reasons that the Manchester patterned dogs are so important to us, because they don't have that piebald gene. I got off track - anyway! I've only seen one pure white Rat, and he isn't deaf, so I am just curious about how color patterns affect hearing. I wouldn't throw them out of my whelping box, but I was curious, mainly because I see so many harlequin great danes.
Sorry! I should have been more specific - the part about breeders putting them to sleep.
ReplyDeleteI have Ratties - and we have just now seeing the effects of extreme piebalding, i.e. dogs with piebald parents being born completely white due to that progression. One of the reasons that the Manchester patterned dogs are so important to us, because they don't have that piebald gene. I got off track - anyway! I've only seen one pure white Rat, and he isn't deaf, so I am just curious about how color patterns affect hearing. I wouldn't throw them out of my whelping box, but I was curious, mainly because I see so many harlequin great danes.
HurricaneDeck -
ReplyDeleteClick on the link provided in the post, and it will take you to a page on white Boxers where they describe the deafness (it's the same as for Harlequins) and how some breeders "put them to sleep" by slipping them into a freezer. Of course, plain old "bucketing" is also done, isn't it? Not talked about much (neither is freezing), but it's done. More on that here >> http://www.columbusdogconnection.com/PuppyMillBill2.htm
Do most breeders have pups euthanized with sodium phenobarbitol by a vet? You would hope, but when it comes to dog breeders, I have learned to keep my expectations low. For a page on home euthanasia of rabbits (about the same size as a puppy) see >> http://www.angelfire.com/wy/deb/euth.html
Patrick
"Just imagine if we did to horses what we have done to German Shepherds."
ReplyDeleteOK, we haven't messed up their hocks as bad as that but...
Some sickeningly large percentage of miniature horses are born with congenital diseases: fixated patellas, slack tendons, foaling death rate of 36%, etc.
There are also some truely awful congenital defects in certain horse breeds that have nothing to do with looks or perfornamce.
In the Arabians there's
Cerebellar Abiotrophy (inheritance ?, no test)
Lavendar Foal Syndrome (inheritance?, no test)
Severe Combined Imunodefficiency (recessive, test available)
In Quarter Horses (and Paints and Appaloosas who's stud books are open to QH)
Hyperkalemic periodic paralysis (dominant, testable)
http://www.youtube.com/watch?v=TpReUsLfDcE
Hereditary Equine Regional Dermal Asthenia (recessive, testable)
http://www.equinejournal.com/articles/herda-a-devastating-inherited-skin-defect
Glycogen Branching Enzyme Deficiency (recessive, testable)
In Paint horses
Overo Lethal White Syndrome (incompletely dominant, testable if not obvious from pattern of white markings on both parents)
http://www.apha.com/breed/lethalwhites03.html
The arabin breeders have been pretty good about testing for SCIDs . Most stallion adds list SCID -/- or +/- so that people can make informed breeding decisions.
Quarter horses and the other stock horse breeds are a different story. HYPP +/+ are not accepted into the registry but +/- animals are. And these horses are just as affected by the disease as the +/+ individuals. Many stallions aren't tested, many win in the ring, and the gene lives and breeds on. (I should note that HYPP +/- gives a bit extra muscle mass which is an advantage in the halter (horse beauty contest) ring. Is it any wonder the registry won't ban +/- horses? HERDA is likewise not widely tested for unless there is an affected individual close up in the pedigree and even then...
The cherry on top is Overo Lethat White Syndrome. The Paint registry has a classification system for white markings that doesn't reflect current knowledge about the four genetically distingt paint genes--one of which is lethal when homozygous. This paint gene, which is often if not usually recognisable TO THE EYE in both parents can also be tested for. But often it's not...
The only thing remotely slowing down the destruction of many horse and pony breeds is the fact that the gestation time is so long. To be sure, MANY equine breeds are being wrecked, but with an 11-12 month gestation (my mare routinely went well OVER 12 months, so it happens) it takes a lot longer to run head-long into ruination than a dog's 63 day gestation allows.
ReplyDeleteSeahorse
HuricaneDeck -- the Google still works! See >>
ReplyDeletehttp://www.chromadane.com/whites.htm
"The unemotional fact is that rescue fills up with deaf/sensory defective Danes as most are abandoned by their breeder and/or owner as unsuitable pets. This is not to say they cannot be managed, but it takes an enlighted home, some specialized training, and of course an awareness of the dog's handicaps & health concerns. Many animal welfare organizations endorse humane euthanasia for ALL (bilateral) deaf puppies for the __puppy's__sake, & most white danes are not only deaf, but may have eye & skin problems as well. And there are far, far, too many Danes in rescue already, not to mention far too many pet Danes out there given the (too few in) number of suitable pet homes. It is a GDCA Code of Ethics violation to knowingly sell a defective (unhealthy) pup as a pet, & any harl breeder worthy of the name knows that white pups will usually suffer from a variety of unpleasant problems which may well continue to arise (& surprise) the owner thru the first year or longer. Traditionally the responsible breeder typically culled such pups to ensure they did not burden the pet-owning population, take a home from another pup, or sell a dog who ended up misunderstood or who continued to cost the owner large amounts in medical or training bills."
Deafness and pigmentation are multi-chained genes.
What I mean by that is that pigmentation and other (unknown) genes seem to have to come together to create the problem. Some breeds have that unknown genes or genes more frequently than others, but the trigger to that gene or genes is coat color or pattern.
All of this is imperfectly understood in some breeds (Jack Russells), but well understood in others (Harlequin Great Danes and Dalmatians, for example).
As for white rats, they are all descended (supposedly) from odd individuals collected by the late rat catcher Jack Black -- there is a post on the Wistar Rats on this blog if you are interested.
P.