Line Breeding

[PkerStr8Tail]

I have seen several topics from people asking who to breed to their females. Many of the reponses indicate you must cross with something in the lines you already have to get results. (you can't just breed two good dogs together and get positive results) Line breeding certainly does give positive results but it begs the questions, "Is line breeding the only method to get results?"

I started to look at some of the great ones from the past and some programs such as Miller's definitely did line breeding, but I saw results without heavy line breeding.

Additions Go Boy - Builder's and Paladin's on top and Rebel on the bottom
Fiddler- Strongman on top and Endurance on the bottom
Guard Rail - Elhew on top and Rebel on the bottom
Rock Acre Blackhawk - Brush Country Spectre and Miller on top and Fiddler on the bottom

What's your opinion?

[ultracarry]

I'm new to this but I was thinking when people like what they have.. they want the same thing and nothing more that could come with different traits that they do not want..

[Cajun Casey]

Linebreeding is done to set traits of a specific dog. The usual formula is to breed a second generation to a first, like niece to uncle. This allows generational outcrossing while still retaining the line. Much linebreeding was done due to regional favoritism and availability. After three generations, the recombination of genetic material is such a mash-up, it's not really that tight unless you are using the same tail lines for the outcrosses.

[RayGubernat]

Pokerstr8 -

Linebreeding and selective outcrossing such as that practiced by Whele and Miller certainly is a huge plus for the breed. Linebreedings purpose should be to provide a stable genetic base which will produce a consistent type of animal. Linebreeding should reduce the probability that wide variations are present in successive breedings of linebred parents. Reproducibility and standardization is(or should be) the goal and the result of proper linebreeding.

When a linebred animal is bred to an animal with different characteristics(an oputcross), presumably to improve the "line" most of the offspring will generally resemble the linebred parent but some will show the influence of the outcross. Those progeny who show an "improvement" in the deired trait or traits while still maintaining a high level of those traits or characteristics that are part and parcel of "the line", would be those individuals who should be selected for further linebreeding and possibly backcorssing to solidify the "improvement" and incorporate it into "the line."

Obviously this approach takes generations to accomplish and that means time and money.

The ideal approach would be to take the linebred dog that you have, evaluate its strengths and weaknesses, then select a linebred mate which has at least adequate performance where the other dog has strengths and has real strengths where the other dog has weaknesses.

That is... I think obviously, not possible most of the time. The next best approach would be to do an outcross on a linebred dog as above and see what you get in that first generation.

What happens far more often is that folks look at what they have and look for a mating dog that will complement the strengths and cover the weaknesses. The outlook is typically very short...one generation, one breeding.
However, when such a mating produces an exceptional offspring or more rarely, several exceptinal offspring, that nick, as it is called is very often repeated...as it should be. Such nicks can be the start of a new "line'.

RayG

[Meller]

If it's all done by line breeding; then I guess there is no such thing as a blue hen.

[PkerStr8Tail]

Maybe my original post missed the mark since most of the replies are explaining why you should line breed. I agree that line breeding works and has worked for years. My question should have been why do some believe that "only" line breeding can produce quality pups. When people ask what to breed to most of the replies say that they need to find a male with the same lines in their background or they are just breeding blind or junk. As my original post said there are many great dogs from the past that didn't appear to have heavy line breeding done to produce them.

Wouldn't it also be accurate to say that programs like Miller or Elhew had to start from something other than their own? Yes after years of labeling their offspring with Miller and Elhew prefixes they are line breeding to their own stuff, but at the start they had to use crosses with other's stuff to start their line?

So, I guess my point is, yes line breeding works well, but to say it is the only way seems short sided.

P.S. Not to mention some of the problems that come from too close of line breeding, such as bad bites, hook tails, bow legged, etc.

[BigShooter]

I don't know how many of the past threads you looked through but I'll try to give you a short answer. With a first time mating whether the dogs are related through line breeding or virtually unrelated you do not know for certain what you will get. After getting a first litter from a first time mating one can evaluate their success.

Line breeding has been used in several species to incease the odds of getting an expected outcome and in dogs - expected traits. With a first time complete outcross the odds are less for getting any certain traits you may want. The short answer is that over time without outcrossing periodically the likelihood is that you will get a more uniform product but fewer truly great specimens due to the "drag of the breed" ( or "move towards the average"). A number of knowledgable breeders prefer breeding the best to the best, without any linebreeding. The problem with all canine breedings is the time involved because often you don't know for a few years how good the pups will really be.

[Trekmoor]

When you get a really good litter of pups it's called linebreeding , when you get a poor litter with genetic faults it's called inbreeding. The dividing line between the two can get a bit hazy at times !

Bill T.

[BigShooter]

When you get a really good litter of pups it's called linebreeding , when you get a poor litter with genetic faults it's called inbreeding. The dividing line between the two can get a bit hazy at times !

Bill T.

[Dave Quindt]

Pokerstr8 -

Linebreeding and selective outcrossing such as that practiced by Whele and Miller certainly is a huge plus for the breed. Linebreedings purpose should be to provide a stable genetic base which will produce a consistent type of animal. Linebreeding should reduce the probability that wide variations are present in successive breedings of linebred parents. Reproducibility and standardization is(or should be) the goal and the result of proper linebreeding.

RayG

So Ray, how do you explain other sporting breeds that have made great strides in improving performance over the last century, produce consistent types and have a great degree of "reproducibility and standardization" but have done so without significant linebreeding efforts? FT Labs are the obvious example, but there are others both in sporting and other working breeds.

Also, considering that in every linebred pairing, the sire and dam were considered at least of breeding quality (we hope) and most likely to be above average when compared to the litter or the breed as a whole, how do we know that the supposed benefits gained from linebreeding were not from pairing quality individuals but were solely due to the pairing of related individuals?

Pokerstr8, I'm guessing that's what you were getting at?



BigShooter wrote:

Line breeding has been used in several species to increase the odds of getting an expected outcome and in dogs - expected traits. With a first time complete outcross the odds are less for getting any certain traits you may want. The short answer is that over time without outcrossing periodically the likelihood is that you will get a more uniform product but fewer truely great specimens due to the "drag of the breed" ( or "move towards the average").

Mark,

While linebreeding (aka inbreeding) has been shown to increase odds of getting an expected outcome I think you'd admit that the bulk of those studies are of limited relevance to the sporting breed owner. Yes, if one crosses and then linebreeds two strains of tomatoes one can show an increase in fruit production, or stem height or whatever other trait one is looking for. The same can be said for cattle; inbreeding can show to increase yield or whatever other trait is being bred for. The problem is that in these instances conditions can be controlled (i.e. multiple inbreeding experiments using tomato plants in a controlled greenhouse, with exactly the same conditions and nutrition, or 500 head of cattle kept in the same pastures with access to the same nutrition, butchered at the same time) AND the results can be objectively and independently verified.

The problem is we're not dealing with simple plants or domesticated herd animals where nurture plays little role. We're dealing with THE most domesticated animal, where nurture plays a more important role than any animal in the world. We are also dealing with extremely complex traits that we know virtually nothing about their genetic make-up or inheritance qualities and most importantly, we have no way to independently determine if the results were due to an inbreeding strategy or despite it!

Regarding "drag of the breed", are you aware of any canine geneticist who accepts or can quantify that term? Because I am not. I have been told that inbreeding depression is not a likely factor considering the relatively mild amount of inbreeding actually accomplished and because canines carry a relatively large set of 39 chromosome pairs. It's my belief that terms like "hybrid vigor" and "inbreeding depression" are not appropriate to the canine populations we deal with, but we use them anyway, generally to suit our personal beliefs and observations.

My point here is not that linebreeding doesn't work. Of course it does; that's how every dog breed was created. I also believe that linebreeding is a strategy that can be useful in breeding sporting dogs. My point though is we have these conversations ad nauseum and throw around these claims about "increasing consistency" and "setting the genes" as if anyone has any real idea applicable they really are. We completely ignore the human element, and try to convince ourselves that we are perfect, unbiased, objective observers with unwavering memories. The problem is that human history teaches us otherwise.

Sorry for the rambling post,
Dave

[BigShooter]

Dave,

I tried to be brief, in part because I've particpated in so many of these threads and partly because the issue, as I've pointed out so many times in the past, has complexities beyond our present scope of knowledge. So how is it that we know for certain the drag of the breed isn't actually the drag of the breeders, owners, trainers and handlers as well as the possible combinations of the genetic soup? If we had no drag on a breed what-so-ever, every breeder of a AA NC could replicate the result with ease.

If someone really wants to learn more I think Dr. McCue's 2001 article carries about the right mix of plain english mixed with scientific knowledge: http://www.dogstuff.info/part1_peas_and_pups.html


Edited for a typo.

[Dave Quindt]

If we had no drag on a breed what-so-ever, every breeder of a AA NC could replicate the result with ease.

Nice false paradigm!

The fact that every puppy from a particular breeding is a unique genetic individual has nothing to do with the mythical "drag of the breed".

To take it one step further, the AA NC can't replicate himself because he's not 100% heterozygous. Even if he was, he's only providing 50% of the genetic material in play.

Now, if you can find a male and female AA NC littermates, both 100% heterozygous, bred them together and show a "drag of the breed" in the pups then you'd have an argument to make. Of course, breeding two AA NCs together results in humans who are expecting nothing less than AA NC quality pups, and those pups will undoubtedly raised & trained differently than their parents, as the expectations are different. Even though the pups are raised and developed with super-heightened expectations, if they don't pan out the reason is never the human element, but the convenient "drag of the breed". Once again, the human ego saves the day

And why is it that "drag of the breed" only applies to ground race? Somehow I never hear about "drag of the breed" when it comes to bird finding, retrieving, intelligence or trainability?

Somehow humans are always the reason why the dogs succeed but "mother nature" is the reason when they don't pan out.

[RayGubernat]

Dave -

I really have no knowledge of the breeding practices of retreiver breeders or any other sporting dogs, other than pointers so I can't comment.

If they are not linebreeding and outcrossing and the performance levels of the breed are improving, then they must be breeding best to best. Tht, of course, works too.

I did mention that most breeders do in fact do just that and that is an effective way of producing quality animals with some of the best attributes of both sire and dam.

RayG

[BigShooter]

Nice false paradigm!

Nothing like mixing apples and oranges again. A genetic clone wasn't specified as a requirement for another NC. Due to the complexities involved, and the limits of current human knowledge, it's common knowledge an identical situation couldn't be created. Furthermore all of this ignores the effect of the competition, the luck of the draw & random variation. Drag of the breed indicates an inability within a line to reproduce identical or improved results on a consistent basis without an outcross. Perhaps though a place to start would be for you to provide a reference source for a definition of the mystical "drag of the breed" term as you intend to use it for purposes of this discussion.

I don't know why you think drag of the breed always refers to ground race. I guess I haven't seen that before. Personally I tend to think & talk in terms of a complete dog.

... over time without outcrossing periodically the likelihood is that you will get a more uniform product but fewer truly great specimens ...

Dave,

Can you provide an example of inbreeding a line without any outcrosses that produced truly great specimens several generations removed from the progenitors of the line?

[Ron R]

Of course, breeding two AA NCs together results in humans who are expecting nothing less than AA NC quality pups

if they don't pan out the reason is never the human element, but the convenient "drag of the breed". Once again, the human ego saves the day

Somehow humans are always the reason why the dogs succeed but "mother nature" is the reason when they don't pan out.

Dave, are you by chance anti-human. It seems that you have a horrible habit of generalizing the thoughts and personalities of all man kind. A breeder, trainer, owner, and handler are indeed a large part of a trial dogs success along with some luck and surely you are smart enough to realize that. Whether you line breed, out cross, or scatter breed you are going to have a litter of pups that are going to be individuals with there own personalty along with different strengths and weaknesses.

[Troy08er]

Dave,

I tried to be brief, in part because I've particpated in so many of these threads and partly because the issue, as I've pointed out so many times in the past, has complexities beyond our present scope of knowledge. So how is it that we know for certain the drag of the breed isn't actually the drag of the breeders, owners, trainers and handlers as well as the possible combinations of the genetic soup? If we had no drag on a breed what-so-ever, every breeder of a AA NC could replicate the result with ease.

If someone really wants to learn more I think Dr. McCue's 2001 article carries about the right mix of plain english mixed with scientic knowledge: http://www.dogstuff.info/part1_peas_and_pups.html

Hey BigShooter,great read. thanks for the post,Troy
I have been doing a lot of research on inbreeding and linebreeding. Have not seen Dr.McCue's report.

[PkerStr8Tail]

If someone really wants to learn more I think Dr. McCue's 2001 article carries about the right mix of plain english mixed with scientic knowledge: http://www.dogstuff.info/part1_peas_and_pups.html

After reading a portion of this material so far it would seem to me that linebreeding is a double-edged sword. Although linebreeding can bring out the positives you run the risk of the unwanted traits(recessives) lining up and showing themselves more frequently as well.

Given the shear possibilities(probabilities) present when a pup is created, to say linebreeding significantly increases the positive outcomes seem ignorant given what I read. To clarify what I mean, it is to say that in a single pup it would not be true, but over a large population of pups it would have some impact.

Which brings me to my last point, which is to say that really most of the large breeding programs that are successful are a numbers game. You whelp hundereds of pups to cull through and keep only the few good ones, then move on to the next generation and do it all over again. Successful breeding is more of a numbers game than anything scientific.

[ezzy333]

Which brings me to my last point, which is to say that really most of the large breeding programs that are successful are a numbers game. You whelp hundereds of pups to cull through and keep only the few good ones, then move on to the next generation and do it all over again. Successful breeding is more of a numbers game than anything scientific.
PkerStr8Tail

I think this is exactly right when you are outcrossing but you change the odds considerbly when you linebreed and especialy when the dogs being bred have been linebred.

Ezzy

[dudleysmith]

Rock Acre Blackhawk -

Longhairs and tri colored.

Brush Country Spectre and Miller on top and Fiddler on the bottom

You decide if that's correct blood. :roll:

basically you are saying WHO knows what is in Blackhawk...

[dudleysmith]

successful breeding is more of a numbers game than anything scientific.

About one of the most logical things posted...

[solon]

My conception of the term "drag of the breed" is that it means the tendency of breedings to produce progeny that move toward the mean or average for the breed. That is to say it is a statistical concept that when you make random selections from of a large set of elements, in this case chromosomes and sub chromosomal elements (that have been exchanged through recombination); these selections happening at miosis, form subsets combined in progeny, i.e. the genotypes of the progeny, will tend toward the average for the breed. Thus with all the complexities of inheritance and epigenetics at play, even though you start with two outstanding parents, the progeny will tend to be closer to average. It would work the other way as well. If you breed two poor specimens, you can generate progeny that tend to be better than either parent.

Inbreeding can contribute to consistency because it creates a higher degree of homozygosity, thus their is less diversity in the selection of alleles at miosis. Inbreeding may also preclude rare super successful gene combinations because the inbreeding results in a smaller pool of alleles in the gene pool of that line compared to the breed as a whole. Outcrossing to another breed, as is sometimes done, can introduce additional alleles that may make a positive contribution to the desired phenotype. Take the Pudelpointer as an example.

Solon

[ezzy333]

My conception of the term "drag of the breed" is that it means the tendency of breedings to produce progeny that move toward the mean or average for the breed. That is to say it is a statistical concept that when you make random selections from of a large set of elements, in this case chromosomes and sub chromosomal elements (that have been exchanged through recombination); these selections happening at miosis, form subsets combined in progeny, i.e. the genotypes of the progeny, will tend toward the average for the breed. Thus with all the complexities of inheritance and epigenetics at play, even though you start with two outstanding parents, the progeny will tend to be closer to average. It would work the other way as well. If you breed two poor specimens, you can generate progeny that tend to be better than either parent.

Inbreeding can contribute to consistency because it creates a higher degree of homozygosity, thus their is less diversity in the selection of alleles at miosis. Inbreeding may also preclude rare super successful gene combinations because the inbreeding results in a smaller pool of alleles in the gene pool of that line compared to the breed as a whole. Outcrossing to another breed, as is sometimes done, can introduce additional alleles that may make a positive contribution to the desired phenotype. Take the Pudelpointer as an example.

Solon

I agree with what you have said except using a pudelpointer as an example of outcrossing to another breed. That was done some where near 150 years ago and any hybred vigor that was obtained would have been completely gone a few years later with all of the line and inbreeding that is done to create any breed of dog. Probably many breeds have had crosses since the pudelpointer was established.

Ezzy

[BigShooter]

Solon,

While I may understand what each of the scientific terms mean, I submit all the post does is create cacophony for the common man. Now if you were to take a stab at reworking what you wrote into plain English, the common eighth grade comprehension level normally preferred on forums such as these, I'm certain that would be appreciated by a certain sub-set of the genotypes here.

[birdogg42]

U guys are using TOO MANY BIG WORDS!

[Trekmoor]

I got lost a while ago !

Bill T.

[lvrgsp]

[quote="BigShooter
Can you provide an example of inbreeding a line without any outcrosses that produced truly great specimens several generations removed from the progenitors of the line?[/quote]


Moesgaarsds IB (pronounced eve)

[BigShooter]

So the coeficient of inbreeding is .100 then. No DNA tests of course. Hmm, I'll have to go back & do some digging. Just give me a hint which progenitors you are basing this on and how many several generations removed from IB they were.

[lvrgsp]

IB was the progenitor, and there are many who are derived from him. In all intensive purposes IB was a line, barring DNA testing and correct pedigreees, but they had a reason, a plan, and a purpose, they had no reason to falsify peds, of course accidents do happen .

[BigShooter]

I'm a little familiar with the Moesgaard line but no expert. If you re-read my question then, I'm wondering what offspring from IB & a single bitch were 100% inbred (not line bred) for several generations and what were the truly great 100% inbred offspring that were produced then several generations later?

This is a question not an inquiry to be used to start a debate.

[lvrgsp]

I'm alot familiar with the Moesgaard line so, I'll answer again and not debate there were many who were inbred on IB both sire and dam for many generations.

One dog ok...Moesgaards Coco, he was a 2 gen, a 3rd gen a 4th gen product of IB he was out of one of, if not the most inbred shorthair litter in the history of the breed. He was a product of inbreeding.
Gentlemen there is no difference in Inbreeding and Linebreeding as terminology speaks, it is the direction it takes you that makes the difference. As Dave eluded to earlier.


Correction to the above as Coco was higly inbred, his Sire Ruffy was even more so but he was out of IB so my reference to Coco was that he was at least 2 gens removed from IB
Ruffy was a product of FATHER/DAUGHTER 3 TIMES. The sire all being IB.


It's great history I'll say that, but some sit around and roll it off the tongue like its a definitive answer to produce better, when in reality the environment and the oppportunities afforded such dogs IMO make a bigger difference.


Riddle me this Batman......Where are the linebred Moesgaard dogs of today from IB?

And let me add this some would'nt know what linebreeding/inbreeding was if it reached back from 1972 and slapped em in the face.
There again of course this is just my opinion.

[Dave Quindt]

So the coeficient of inbreeding is 100 then.

No; the only way to get a COI of 1 is to breed identical twins. Full siblings are .5, half-siblings .25. Even with intense inbreeding, it's very difficult to get a COI much above .4.

[solon]

I agree with what you have said except using a pudelpointer as an example of outcrossing to another breed. That was done some where near 150 years ago and any hybred vigor that was obtained would have been completely gone a few years later with all of the line and inbreeding that is done to create any breed of dog. Probably many breeds have had crosses since the pudelpointer was established.Ezzy

Bill Brink wrote the following on the SS BBS recently:

Hank raised numerous litters over the years, one of my favorites was a litter by Billy Ball's Builder Risk. The black headed pup I purchased, trained and won with was named Security Risk. I won with him in open and amateur shooting dog stakes throughout the Midwest and hunted nearly all the gamebird species with him. Interestingly another littermate went to the Canadian prairies with trainer Mike Rashata and won all-age and shooting dog stakes, was later purchased by Ed Rader, trained for the bird field trials, won a lot of NSTRA competition, and then became the outcross dog for Bodo Winterhelt's pudlepointer breed.

I think Bodo is still around and less than 150 yrs old. I am sure you are right about using the pointer 150 yrs ago as well, but perhaps that is not the last time the pointer was used in the Pudelpointer breed.

As far as drag of the breed goes. Think of it this way: represent one dog, the sire, as a set of cards that includes all the spades and hearts from a deck and represent the dam as having all the diamonds and clubs. Now select at random one of each denomination from the sire and dam and combine. You end up with pairs of each denomination that are a mix of spade or heart with a diamond or club. Now lets say as part of this thought experiment that it is the spades and clubs, the black suits that confer the high qualities of the sire and dam. You may get a progeny with lots of black at each denomination, but on average you will get a random mix more like you would get if you selected your pairs from a fully shuffled deck. It is the random selection of one out of each pair that gets passed to the progeny card hand that creates a new mix which if you repeat this and create a large number of such hands from this sire and dam will tend toward the average for the deck used.

To extend this analogy further, a given breed is homozygous for a lot of alleles (particular forms of a given gene or regulatory element), that is the cards for each denomination are the same suit. Thus the sire for its Aces, might have both of them spades. In that case, the random selection of one Ace for the sperm to contribute to the progeny makes no difference, it will be an Ace of spades either way. So inbreeding is a process by which you can increase the level of same suits at various denominations over and above that which is average for the breed as a whole. You can see how this reduces the diversity of the hands that you would get. You can not take this to the extreme however, as most organisms are not viable if homozygous at all loci, as would occur with parthenogenesis.

Maybe this analogy helps with the concept. Of course with the real world with 20,000 or so genes and many more important genetic elements, more than 4 alleles possible, linkage of genes into blocks, the largest being whole chromosomes, and all sorts of other more complicated genetic and epigenetic effects, The deck of cards is a gross oversimplification.

Solon

[dan v]

Solon,

I really think the "drag of the breed" or "drag of the race" is really hard for people to understand. I think a better term would be "trend to average". I prefer thinking of the trend to average on the terms of a Bell Curve.



Breed to bad dogs together, odds are you will get something better, maybe not alot better, but better. Conversely, breed two great dogs together you probably won't get better, maybe not even the same, and more likely not as good......both examples will trend towards the high point on the Bell Curve...average for the breed.

[ezzy333]

Solon,

I really think the "drag of the breed" or "drag of the race" is really hard for people to understand. I think a better term would be "trend to average". I prefer thinking of the trend to average on the terms of a Bell Curve.



Breed to bad dogs together, odds are you will get something better, maybe not alot better, but better. Conversely, breed two great dogs together you probably won't get better, maybe not even the same, and more likely not as good......both examples will trend towards the high point on the Bell Curve...average for the breed.

Exactly right. Take the best of anything and you will have a problem even maintaining it let alone continued improvement. And the opposite is just as true, when you take the poorest the offspring will be better and you would have trouble maintaining that poor quality. Things always move to the average and breed improvement means the average has to improve and not just an individual. However that individual, can and does improve the average when it is line-bred back to the close relatives to set that improved status as the norm or average.

Ezzy

[dan v]

However that individual, can and does improve the average when it is line-bred back to the close relatives to set that improved status as the norm or average.

Ezzy

I don't think it's needs to be linebreeding in the strict sense however, I think a person could select for traits and breed that way. Assortive matings.....bred like to like.

[ezzy333]

However that individual, can and does improve the average when it is line-bred back to the close relatives to set that improved status as the norm or average.

Ezzy

I don't think it's needs to be linebreeding in the strict sense however, I think a person could select for traits and breed that way. Assortive matings.....bred like to like.

True but if you don't linebreed to set those traits then it will slip back quicker. Thats my only point.

Ezzy

[dan v]

However that individual, can and does improve the average when it is line-bred back to the close relatives to set that improved status as the norm or average.

Ezzy

I don't think it's needs to be linebreeding in the strict sense however, I think a person could select for traits and breed that way. Assortive matings.....bred like to like.

True but if you don't linebreed to set those traits then it will slip back quicker. Thats my only point.

Ezzy

I think my point was that I think you can breed like traits to like traits, regardless of pedigree and remain static or improve said traits. You are really linbreeding traits, not the pedigree.

[Dave Quindt]

Solon,

I really think the "drag of the breed" or "drag of the race" is really hard for people to understand. I think a better term would be "trend to average". I prefer thinking of the trend to average on the terms of a Bell Curve.

Breed to bad dogs together, odds are you will get something better, maybe not alot better, but better. Conversely, breed two great dogs together you probably won't get better, maybe not even the same, and more likely not as good......both examples will trend towards the high point on the Bell Curve...average for the breed.

Dan,

Ever Google the phrase "drag of the breed"? Try it some time, and look at the results. Compare that to any other phrase commonly used in these discussions (i.e hybrid vigor, inbreeding depression, coefficient of inbreeding, etc). Why is it that all of those terms get you hundreds of results from academic and research sources but not a single one when "drag of the breed" is used? (Drag of the race, species, etc gets you the same things; no real scientific documentation of the concept).

I could write paragraphs on all of this, as I think much of what’s posted here is little more than urban legend with no direct scientific evidence, but in the spirit of brevity let me just say this……

To me, "drag of the breed" is a catch-all concept used by dog folks to explain a phenomenon that was common in occurrence but lacked any reasonable explanation; the fact that dogs would display one trait but often not pass it to their offspring

Of course now we know the reason why dogs display one trait but often do not pass it to their offspring, even if the other parent displays the same trait; what you see isn't exactly what you are going to get. It's not "the drag of the breed" causing high-tailed dogs that don't pass that trait to their offspring, it's because while their phenotype allowed for a high tail, their genotype passed to their offspring did not.

We want to claim “cause and effect” because it’s empowering to do so. But unless and until we understand all of the factors at play, and we certainly don’t understand them today, anyone who claims to understand cause and effect when it comes to dog breeding should be challenged, whether it’s Bob Wehle, Dan Voss or Dave Quindt.

Going to leave it there…….

Dave

[PkerStr8Tail]

We want to claim “cause and effect” because it’s empowering to do so. But unless and until we understand all of the factors at play, and we certainly don’t understand them today, anyone who claims to understand cause and effect when it comes to dog breeding should be challenged, whether it’s Bob Wehle, Dan Voss or Dave Quindt.

Going to leave it there…….

Dave

I would agree with this. I would also add that most of the perceived success of the breeding programs that people quote and point to are mostly due to great marketing. The average person only sees the end result and thus determines that these prgrams were very well done and thought out processes. I am not saying it is all luck and no thought is put into it. The reality is the programs and dogs that have left their mark on the breed are a result of large numbers of pups born with only the few elite plucked out and those few are the ones the public knows about. Don't get me wrong, the method has worked and has had success. It's just the misunderstanding by the public that believes these offspring are a result of careful breeding procedures or well planned linebreeding. For every Miller's White Powder or Miller's Silver Bullett, there were hundreds upon hundreds of pups that didn't make it to public view.

[dan v]

[quote="Dave Quindt"

Going to leave it there…….

Dave[/quote]

Did I just get taken to the woodshed? If so, I'd like it to be more clear. If not, again, I'd like it to be more clear.

[dan v]

For every Miller's White Powder or Miller's Silver Bullett, there were hundreds upon hundreds of pups that didn't make it to public view.

Economy of scale. It will move the ball down field.
A litter every 12 months, well, it might move the ball...but you may need a micrometer to measure the progress.

[ymepointer]

Dan,

Ever Google the phrase "drag of the breed"? Try it some time, and look at the results. Compare that to any other phrase commonly used in these discussions (i.e hybrid vigor, inbreeding depression, coefficient of inbreeding, etc). Why is it that all of those terms get you hundreds of results from academic and research sources but not a single one when "drag of the breed" is used? (Drag of the race, species, etc gets you the same things; no real scientific documentation of the concept).


Going to leave it there…….

Dave

Dave a more elegant search than "drag of the breed" would beto search for the term fillial regression, or the phrase "Law of fillial Regression"...Try it some time, you'll like it

Check this link out for instance..
http://www.nature.com/hdy/journal/v81/n ... 4180a.html

[Dave Quindt]

[quote="Dave Quindt"

Going to leave it there…….

Dave

Did I just get taken to the woodshed? If so, I'd like it to be more clear. If not, again, I'd like it to be more clear. [/quote]

Dan,

Not my intention at all. After building a rather lengthy post I came to the conclusion that I really wasn't up to defending all of it. While I'm a firm believer that a little information is a dangerous thing, I didn't want to be the shining example of that old truth

Dave

[Dave Quindt]

Dave a more elegant search than "drag of the breed" would beto search for the term fillial regression, or the phrase "Law of fillial Regression"...Try it some time, you'll like it

Somewhat familiar with the concept. The problem is that it has the same limitations as Wright's Coefficient of Relationship; both apply only to genes and not traits, and don't take into account all of the things learned in the last 100 years, like sex-linked genes and polygenic traits.

FWIW,
Dave

[dan v]

Dan,

Not my intention at all. After building a rather lengthy post I came to the conclusion that I really wasn't up to defending all of it. While I'm a firm believer that a little information is a dangerous thing, I didn't want to be the shining example of that old truth

Dave

That can be a problem...opening ones mouth, and then having to spend the next week defending your position. That and having to scroll for 10 minutes to get to the bottom of the page.

[lvrgsp]

Try scrolling and reading it on a Crackberry, takes a bit for one page to load.

[BigShooter]

So with line breeding/ in-breeding, how do we avoid the movement to the average (drag on the breed ). Well the movement to the average (drag on the breed ) assumes a population is allowed the freedom to intermingle & reproduce. What breeders have done of course is select & breed what they consider to be the best specimens in each succeeding generation, thereby ignoring the rest of the offspring produced (to the OP's point). Excluding the balance of the produced offspring, not including them in the calculation of an average has the potential effect of reducing the movement to average (or the drag on the breed ).

Back to the OP's original question, is line breeding the only way? I would answer it this way, breeding the best to the best is the same method whether applied to line breeding or breeding traits to traits. Increasing the homozygousity (two of the same genes in a pair) through line breeding does not however guarantee anticipated results nor avoid unintended consequences. In a non-line breeding (or outcross) there also exists the potential to produce a super successful or super unsuccessful combination not possible within a given line.

[dan v]

Back to the OP's original question, is line breeding the only way? I would answer it this way, breeding the best to the best is the same method whether applied to line breeding or breeding traits to traits. Increasing the homozygousity (two of the same genes in a pair) through line breeding does not however guarantee anticipated results nor avoid unintended consequences. In a non-line breeding (or outcross) there also exists the potential to produce a super successful or super unsuccessful combination not possible within a given line.

One of the mods can lock this thread now........

[kensfishing]

It was just getting interesting. With all the big words and quotes. I other words it's probably over most of the people on this board head. Right.

[BigShooter]

One of the mods can lock this thread now........

Does this mean I just jumped into the hot water again or just got out for a little while?