Does the underbite seem to be dominate or recessive?
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Does the underbite seem to be dominate or recessive?
I'm not knowledgeable enough to make an informative statement.
http://www.thepitbullbible.com/forum...p?dog_id=24651
This dog has a horrible under bite. Combine it with his color and he looks like a Pug on steroids. Jacked up mouth and head.
In several breedings has thrown some of the most perfect scissor bites one would ever see. Muzzle lengthened and all.
With that said, I would guess recessive, at least in this dog.
EWO
Or typically referred as "Undershot" in bulldogs. I'd have to guess recessive but that's just a guess.
Adding to your question topic...someone chime in if they've ever had an "Overshot" bulldog, or "Parrot Mouth". The line I run is said to throw it occasionally, after nearly 20 years of the same family I've got a pup who is slightly overshot.
S_B
The pup.
I had one dog that was overshot really bad. They call it parrot mouth like you said above S_B. After all of the dogs I've bred through the years, he was the only one I ever saw. It made it worse that he was the only dog born out of the breeding. It was also an out cross breeding.
He tested out good, but I just couldn't breed him back into anything. I always figure that things like that can be passed on and I don't want to take the chance of creating more dogs like that. There were a lot of people that still wanted to breed to him.
I agree Osagedogman as far as breeding goes. I'm hoping this guy doesn't get any worse as he ages, so far it's slight and doesn't affect him. He's a tough lil guy and smart....he's bred pretty tight so I suspected something may crop up.
S_B
When I say my dog had an overbite, I mean he had a really hugh overbite. The picture you posted, IMO is nothing to worry about. My dog had at least an inch gap between his upper and lower front teeth. It was like his bottom jaw was at least an inch shorter. He could still use his mouth and hang on, but it didn't really work that well and put a lot of strain on his bottom jaw.Quote:
Originally Posted by S_B
I've run Alligator dogs for 20 years. Lots of undershot animals. I've evolved as a owner, breeder, of course my eye has improved over 2 decades as well and one has to have a pretty solid package all the way around to be bred now at my place.
The problem I run into is that the undershot dogs I have, cannot - typically, be bred back into the Alligator side of things b/c their undershot can result in such excessive deformation it doesn't matter what the rest of them is b/c their muzzle is too short, teeth are jacked up, etc.
Look at and evaluate the WHOLE of the picture - not just one part.
I have this one http://www.thepitbullbible.com/forum...p?dog_id=52033 and she is very undershot as is her mamma, Expresso. Expresso is one of Mr. Hammonds heaviest Alligator dogs and she has what I would consider an inbred looking dog but has produced some really nice bulldogs even when bred back into the family. My buddy had one off her and Zacatecas and man she was a well built dog but also was undershot. The littermates to my Java Express were these 3 males that looked like clones of each other and all had perfect scissor bites and nice muzzle length. In general though most of the dogs that I saw that came out of Expresso were not undershot so I would say this is a recessive trait for sure.Quote:
Originally Posted by No Quarter Kennel
NQK,thanks for your input. Down the road I might breed this bitch and was thinking to something like this http://www.thepitbullbible.com/forum...p?dog_id=53329 . Would you say this might be tight since she is already suffering from some unwanted recessive traits? Sorry to get off topic
This might be an article of interest. You have to realize that the female you have has a lot of wonderful qualities and is still growing and changing. These aren't show dogs in my opinion but working/hunting dogs that figure out how to get things done. With that being said maybe this article will shed some light on some old held beliefs that don't hold true anymore. Read below for some might not have a word program so sorry for that assumption.
Gator
The Mystery of the "Bad Bite"
Elementary, My Dear Watson
by Diane Klumb
Anyone who knows me at all probably also knows how totally excited I am by the ability of molecular genetics to solve the mysteries inherent in the breeding of purebred dogs. In addition to allowing us to actually "breed for improvement" instead of just blithely throwing the term around, I firmly believe that if used wisely, this new store of knowledge represents out best hope for both preserving the sport of dog breeing for future generations, and for fending off our own personal Professor Moriarty in the guise of Ingred Newkird & Co. But actually using this new knowledge to our benefit, and to the benefit of dogs, often requires us to discard long-held and long-cherished beliefs.
Realizing that something we were taught years ago (and in many cases have passed on to the next generation of breeders) was based on an incorrect assumption, and may actually be flat-out WRONG, can be a difficult mental pill to swallow, and some people just can't seem to do it.
For others, it provides an "Ah-HA!" moment, when the seemingly inexplicable suddenly becomes clear.
One such moment for me occurred a few years ago, when I learned that prenatal disruption (via genetics or environment) of a regulatory gene with the delightfully improbable name sonic hedgehog (SHH) often results in asymmetry, where the two sides of a dog don't exactly match. (It's a lot commoner than you'd expect, actually, and occurs in people to varying degrees as well. And symmetry in people has been linked to both beauty and longevity. Probably true in dogs as well.)
More to the point, an asymmetric dog will invariably crab, as he has longer reach and more drive on one side than the other, causing his forward progress to eerily resemble that of a '63 Ford Fairlane with a bent frame. Yet stacked in profile the dog displays flawless balance, which has confounded judges and breeders since time immemorial.
When I shared that discovery in a column a few years back, an amazing number of judges who read it made a point of telling me that it was an "Ah-HA! moment for them, too. (One told me that now whenever she sees a dog crabbing, she checks the elbows on both sides, and one is invariably set higher on the ribcage than the other.) An old dog show mystery solved by molecular genetics. Cool.
I had another of those "Ah-HA! moments recently, when I stumbled upon a fascinating research paper while looking for something else entirely. (Happens to me all the time.)
It seems that scientists have discovered that the size and shape of the mammalian mandible (or lower jaw) is controlled by a surprisingly large number of genes - over 15 have been identified to date.
A little more digging revealed that an equally large number are involved in the development of the maxillary complex, or what we refer to as the upper jaw.
The kicker is......they are different genes, and inherited pretty much independently. Which means, in terms expressed as simply as humanly possible: A DOG CAN INHERIT HIS UPPER JAW FROM ONE PARENT, AND HIS LOWER JAW FROM THE OTHER. Ah-HaH! Another dog-breeding mystery solved, and a long-cherished belief laid to rest.
Putting this into an everyday breeding scenario, here's what too often happens. A young health-screened dog of quality with a magnificent head is widely used by breeders on bitches whos heads could use some improvement--depending on the breed standard, their muzzles could be a little shorter, or a little longer, or maybe a little more or less refined.
But rather than the overall improvement in the first generation breeders are hoping for, they get maybe one nice bite (if they're lucky and depending upon what the bitch's parents looked like) and a basketful of "bad" bites. (What constitutes a bad bite varies from breed to breed, of course.) Soon the word goes round that this lovely-headed dog "throws bad bites" and his stock drops faster than Lehman Brothers. Happens all the time.
And now we learn that it wasn't his fault at all, poor guy. Breeders have been laboring for years under the misconception that an off-bite is the result of an AR gene, and that some dogs are carrying a recessive gene that causes them to "throw bad bites." I've heard it said a thousand times over the years, and so have you.
But it is simply NOT TRUE. Turns out there is no single AR gene for an undershot bite, or an overshot bite, either. There are literally dozens of genes involved, all inherited more or less independently.
So, from this day forward (unless you are one of those people now recognized as incapable of changing a long-held opinion in the face of new evidence due to insufficient activity in the anterior singulate cortex and I'm wasting my time here) we can all stop blaming the poor stud dog.
What is actually happening genetically is this: Given Mendel's Law of Independent Assortment, which is still scientifically valid after all these years, a percentage of the pups from an "unlike-to-unlike" breeding in the head department will inherit a larger percentage of the genes for a longer mandibular (under) jaw from one parent, and a larger percentage of the genes for a shorter upper maxillary (upper) jaw from the other, resulting in bites that are undesirable per a particular breed's standard. NEITHER parent is to blame - malocclusions of the jaw, we now know, are polygenic.
Now, hopefully most of us already understand that there is a huge genetic difference between a MALOCCLUSION OF THE JAW and MISALIGNMENT OF INCISORS, which cause a reverse scissors bite in a dog whose jaws align according to the standard, and whose "puppy bite" is often perfect. Misalignment of incisors is usually caused by no more than the particular timing of the eruption of the individual permanent teeth - if it is off, the upper incisors will force the lower ones out, resulting in a reverse scissors. (That's why it's correctable with mere pressure.) There's no sense blaming this one on either parent, either:
Research has shown there are more than FIFTY different genes that influence the development, and timing of eruption, of teeth.
Some of these genes, it turns out, are involved in other processes and also code for traits that we've actually selected FOR over the years---the MITF gene, for example, which is involved in pigment development (parti-colored dogs are parti-colored because they carry a mutation on this gene) is also involved in toogh development and timing of eruption, which is likely why the parti-colored pups in a litter often get their teeth later than their solid-colored brethren. The RSPO2 gene is also involved in tooth development, and a mutation on this one is responsible for canine head furnishings. (And that's just two off the top of my head- no doubt there are dozens more, as we now know that genes "multi-task.)
The route to overall improvement in bites within a breed
IS THE SAME ROUTE THAT HAS REDUCED HIP DYSPLASIA
in several breeds over the last few decades ----
SELECTION.
This probably explains why wolves -uniformly long-muzzled, solid-colored, and generally free of head furnishings - rarely display the anomalies in dentition that plague purebred dogs.
Now, I'm NOT suggesting for a moment that we should be trying to put a ''wolf head" on all our dogs, or to make them all solid-colored or clean faced-- to do so would seriously affect breed type in probably two-thirds of them, and not necessarily for the better.
What I AM suggesting is that simply understanding that malocclusion of the jaw and misalignment of incisors both appear to be polygenic, rather than the result of a single recessive gene, allows us to make more informed breeding decisions. Breeding a male with a gorgeous head to a bitch who is lacking and expecting the resulting puppies to all end up with his head (and bite) is about as silly as breeding a dog who is OFA Excellent to a dysplastic bitch and expecting the resulting pups to all end up OFA Excellent. No one with half a brain would blame the sire in that situation, because (hopefully!) we now all understand that canine hip dysplasia is polygenic, and represents a threshold characteristic.
The route to overall improvement in bites within a breed is the same route that has reduced hip dysplasia in several breeds over the last few decades--SELECTION. And as the German Shepherd breed has proven conclusively with its OFA ratings, you can do it without sacrificing breed type. Rather than discarding a quality health-screened male with a correct head per his standard who produces off-bites when bred to bitches with poor heads, it would make more sense to selectively linebreed off him, using only those offspring who inherited his head and petting out the rest. After three or four generations of this, the line should be homozygous for his head, the pedigree will have both depth and breadth in that regard, and malocclusions will be few and far between. What we'd be doing is simply combining time-honored animal husbandry practices with knowledge gained from cutting edge molecular genetics. It's the future of responsible dog breeding.
However, refusal to change one's long-held beliefs regarding mode of inheritance (i.e. continuing to believe that there is a single recessive gene for "bad bites" and that a dog who produces one is "a carrier") as new information becomes available to us will untimately result in failure to improve. Why? Because the breeding techniques used to reduce or eliminate the incidence of a trait caused by an AR gene will always be different than those used to reduce or eliminate the incidence of a threshold trait caused by polygenics, where gene testing is not a viable possibility.
And consistently producing sounder, healthier dogs is more important now than ever because, make no mistake about it, the wolf is at our door.
See you at the shows, and remember to have fun out there!
-DK
Nice find Buckgator! Okay so it is polygenetic and both the top and lower jaw each receive their own set of genes that determines the jaw length independently of each other. Now my female is from Expresso who is undershot and has thrown some undershot dogs so does that mean she is throwing a long lower jaw or a short upper jaw I wonder? After reading the article I understand it isn't just a single recessive gene that causes underbite but actually several genes but is all the information for say one given jaw (top or bottom) coming from one parent or are the genes that are received for lets say the lower lower jaw a mixture of genes coming from both parents? Lastly, it still seems like the gene combination for an undershot dog is recessive......I think lol. It seems when an undershot gyp is bred to a dog with a good scissor bite most of the litter comes out with decent bites, not undershot jaws. I suppose that is maybe a reflection of each dogs ancestry though and not just the individual.
The genetics for undershot jaw appear to be multiple and depending on how many line up depends on the severity of the length. I think with that being said you can have a male that has a lot of genes for a shorter jaw and appear normal but when bred to a female with predominance of genes for undershot might turn out that the litter are right in the middle with their bite since they blended their traits. Leg length is the same, not just simple recessive or dominance; long legs are a combination of recessives, then middle leg length is a combination of recessives and dominant genes, then short legged individuals are dominant genes showing the short legged phenotype. The thing that complicates this scenario is when you get individuals with hybrid vigor that appear larger but in fact are not the long legged recessive types and end up throwing whatever the combinations the parents had given the individual when they are bred.
More things to watch for when putting the punnet square together. I think the best bet is to learn what to look for and then when breeding keep track of the results. This sounds complicated and can be but with a little effort and good notes the puzzle starts to form a picture. Another example is when you have a genius and he/she breeds outside the family....the genius is lost thus we realize this trait is recessive even though it is polygenic. Individuals born to the genius type more than likely are very smart thus have a number of the recessives but not enough to put them in that category. The daughter or son were to go back to the parent then their might be a good chance of producing Genius type children. This could be done multiple times and lock in the trait if the resulting progeny were viable and able to reproduce.
When John Lloyd started inbreeding his B. Davis Boomerang dogs. Started getting some really bad undershot dogs. When Mr. W. Truett was visiting John many years back. John had a young very under shot inbred Boomerang male dog. John was considering, putting down this dog because of this bad defect.
Mr. Truett asked for the dog which John let him have this dog. Mr. Truett registered this dog as Truett's Hercules and called it Mr.Ugly. Hercules was one ugly critter. LOL Hercules turned out to be a very deep game little dog. When bred to Mr. Truett's bitches and later one of my bitches. All of the dogs,male or female had normal long muzzles with a good bite.
IMHO do not advocate breeding dogs with bad defects, sometimes their are exception to all rules, but still might come back to haunt you at a later date. One way that can really bring out the bad defects, if back in the blood line, is by a Brother/Sister breeding. Mr. Carver's thoughts on this was; you double the goodness but triple the junk. Brother/Sister breeding should be a last resort with both dog and bitch showing to be excellent built game dogs. Cheers
I think the real key to this is to breed to a dog with not too long a muzzle or too short lower jaw but to an individual that has a good balance of everything. I believe staying in the family is the most consistent way to do it but will probably take more time to do it. I think breeding is like steering a boat you have to keep it on coarse. I think the devil is in the details and requires you to steer it a little and know which direction it is going and deciding if it needs adjusting. Breeding to the ideal individual seems to be the most probable direction for success in the long run in my opinion.
Personally, I would never make that breeding. I consider that way too tight. Too much of the same with little to no complimenting factors or characteristics. My Hugo dog is a solid animal with great structure and a gene pool heavy in Hammonds but diverse in blood. I would take your bitch to something like him in the family or an out of some sort. Hugo is currently at Stud at GH's place.Quote:
Originally Posted by Milehighmisfit
NQK,
Thanks for the insight. I know Mr. H. also values genetic diversity and tries not to get too tight but he seems to be having success still with the real heavy Alligtor breedings such as Rachorse to Breyla. I like the way Hugo is bred! I think that would click with something like my gyp as the Parkson/Hailstone connection is there but Scotch is an out and even though doubled up on Calley I know what an awesome gene pool that is and should compliment what I have. Has Hugo been bred to anything yet? A topic for another thread, I would love to hear some input into why some strains like the LG line, or Redboy line seem to thrive more on inbreeding than other lines.