Dalmatians as fire dogs

One of the reasons dalmatians are fire dogs is that 10% of them are deaf due to the crushing inbreeding needed to get white dogs with black spots. They weren’t as distracted by the noise of the death screams, sirens, etc.

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Why are firehouse dogs usually dalmatians?

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Um–death screams? :eek:

Rebecca Henson, while I wouldn’t be surprised to learn Dalmatians are inbred (many purebreeds, especially from show-winning pedigrees, are), or even that said inbreeding leads to 10% of them being deaf, I find it extremely dubious that

White with black spots isn’t such an unusual pattern; you see it in nature all the time. I doubt excessive inbreeding would have been necessary to produce it in dogs.

And anyway, the Dalmatian is acknowledged to be an “ancient breed.” Even if it had been produced originally through unwise inbreeding, there’ve been centuries, if not millenia, since then to diversify and stabilize its gene pool. If 10% of today’s Dalmatians are deaf, and it’s a genetic defect, it’s a defect caused by modern breeders; it’s not an artifact of the breed’s creation.

From this website, http://www.lsu.edu/deafness/deaf.htm

http://www.lsu.edu/deafness/genetics.htm

There’s lots more technical stuff on the genetics of deafness in dogs, but (a) I don’t want to violate Dr. Strain’s copyright by posting it all here, and (b) I don’t get it anyway. :smiley:

Rebecca, as you can see, there are other breeds of dogs that are prone to genetic deafness. Besides the breeds mentioned above,

If firemen really do want a fire dog that’s congenitally immune to “death screams”, maybe they ought to stock up on white Norwegian Dunkerhounds. :smiley:

And as for “the crushing inbreeding required to get the desired coat color”, Dr. Strain also says:

What you’re probably thinking of as “crushing inbreeding” is what animal breeders everywhere call “line breeding”.
A simple explanation of line breeding is:
http://www.bluegrace.com/linebreeding.html

“Lines” refers to the family tree of the dogs. In this example, the Figjam lines and the Boomerang lines have no common ancestors all the way back for 10 generations. When you’re breeding your own dogs in your kennel, say “Boomerang”, you usually have daddy dogs and mommy dogs, none of whom are particularly closely related to each other. You send the mommy dogs to other people’s daddy dogs to get bred, and people send their mommy dogs to your daddy dogs to get bred. All these dogs are distantly related–they’re like cousins many times removed. So you have a kennel full of dogs who aren’t really that closely related.

But suppose you want to cross your “line” of dogs with somebody else’s “line” of dogs, say “Figjam”. This is called an “outcross” and it’s difficult to predict what sort of puppies you’ll get. They might be brilliant and gorgeous; they might be total wastes of DNA.

However, what you CAN do, once you have your Boomerang/Figjam puppies, and they’re all grown up, is breed them with others of your Boomerang dogs, who will of course be very closely related to them indeed, depending on who they are.

So, out of desperation, this breeder has resolved to cross her lines with someone else’s lines (an outcross), and then either breed some of those Boomerang/Figjam puppies to their full littermates (brother/sister), or to their half-brothers and half-sisters back at the Boomerang kennel, or to their Boomerang uncles and aunts, or possibly to their own fathers and mothers.

By homo sapiens’ cultural standards, which prohibit incest in nearly every human culture on the planet, this sounds like a horrible thing. However, it’s something that livestock breeders have been doing ever since people started domesticating animals and noticed that a daughter goat bred back to her father sometimes had the effect of fixing a characteristic in their flock of goats, like coat color or increased milk production.

For the perusal of anybody who comes along and can make sense out of it:
Pictures of different Dalmatian coat colors and explanations of their genetics:
http://www.geocities.com/paisleydals//color.html

A serious discussion of canine color genetics:
http://bowlingsite.mcf.com/Genetics/ColorGen.html

I have heard - and it’s been my experience - that all totally white cats with blue eyes are deaf. - Jill

A little research just showed me that not ALL white cats with blue eyes are deaf, but a higher proportion of them are than are cats of other color combos.

Also, if the people in the burning building had better breeding, they would avoid screaming as they died, knowing the needless upset it would cause their friends, relatives and fire-dogs in the area. A slight moan or two is usually considered adequate, and avoids crushing the dalmations by unnecessary over-breeding.
[hijack] [fan gush]** Duck Duck Goose ** - your posts, usually gently-phrased, often devastating and always inexorable in their quest for calm rational thought, bring me great joy. hehehehe. I can only aspire… Thanks! [fan gush] [/hijack]
And Rebecca - welcome!!