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RCNZ
New Zealand
JH
Posts:26
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| 10/09/2010 5:41 PM |
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MOOSE1- In my opinion, the problem isn't with people that think line breeding is the ONLY way to go. It's with people that think there are any hard and fast rules when it comes to breeding.
In my opinion, the linebreeding/inbreeding vs outcrossing is a load of crap. Every GSP everywhere is the result of line breeding/inbreeding to some degree. For the sake of clarity I'll stick with the term line breeding. They all share common ancestors, it just depends on how far back you have to go. There are a limited amount of alleles available within the breed. Anybody saying they are going to outcross there GSP with another GSP isn't really grasping the concept of it. An outcross is GSP to Weim or GSP to Lab etc. It is however a commonly misused term that has taken on a new meaning, I'm just highlighting it to prove a point. GSP breeding is line breeding, only the degree of how tight the linebreeding is varies. Sometimes it is advantageous to go to a closer relative and sometimes it's better to go a bit farther away. Which to do at what point isn't cut and dry and won't be until the entire genome of the dog is mapped and we can decipher the exact genotype of breeding animals. Like you say up until then it's a bit of a crapshoot. That is until you have a consistent line that breeds true.
As for pictures...always glad to share
Not his most stylish point but he was in a good spot for a photo shoot
Pheasant hunting on the west coast
Racing my german bred weim along the beach. I drive my truck down the coast and they run along side. They were doing just over 40 km/hr for about about a mile on this run. He always leaves her in the dust.
Tracking a wouded Sambar hind through a coastal pine forestry block for a client. Shortly after this picture was taken I gave my rifle to my buddy and told him to keep close so I could keep up with Quin tracking through the brush. About 500 yards later Quin tracked the hind to it's wound bed and we determined we had just bumped it. He tracked to the next rise and indicated it was real fresh so we came over the ridge real careful and spotted the hind. It was just a grazing shot and she looked healthy so I decided if I couldn't get a clean shot I'd leave her be and she ended up moving on before my buddy got there with the rifle. I'll never leave my rifle behind again.
Pixie bee- what affect does a missing tooth or two have on the dog? I assume the teeth you are talking about missing are the premolars? Obviously a missing canine tooth would be an issue but I know quite a few dogs (all Labs) that are missing 1 or usually 2 premolars and have no issues with health or performance as retrievers. There may be something I'm missing but it seems to me to be one of those things that shouldn't preclude an otherwise excellent dog from being bred as it's not really significant in the performance or health of the dog. Is there something I'm missing?
Almost heaven GSPs- No worries, thanks. I'm in vet school and have an undergrad in animal science with a focus on animal production. My mom and aunt breed dogs and I have been involved in breeding sport horses and worked with some good weim breeders. It's very nice to have this forum available with so many knowledgeable people as the specifics of GSPs are what I'm trying to pick up.
I posted his pedigree in an earlier post but it kind of gets lost in the muddle.
http://www.perfectpedigrees.com/4genview.php?id=3081
I doubt I'll have any luck finding much of his line in the states but it'd be great if I could. He has one Kurzhaar 3 gen back and another 5 back but other than that he's pretty much straight AUS/NZ lines all the way back to the original imports brought into this part of the world. I've met a lot of the people involved in putting together the lines behind my dog's lines and about once a month I take him out to run in front of a long term field trial judge that was one of the mainstays in the breed here. It's been a very interesting education.
Random sidetrack...Breeding and the general attitude toward working dogs (for the most part) here is very interesting and a sharp diversion from the US. Dogs aren't given the same status as they are in the states and regarded more like livestock than family members. Dogs are necessary for life here. By my understanding it is the only developed nation in the world who's economy relies on agriculture. The agriculture here is mostly sheep/beef and a growing dairy sector. Dogs are relied on heavily in sheep and beef and to a lesser degree in dairy. The country is too rough to work sheep and beef without dogs. You just couldn't muster half the stock without a team of good dogs. The way they breed is very interesting and no one can deny it's effectiveness. They have no qualms about inbreeding and bad dogs don't live long enough to reproduce. A somewhat toned down version carries over into the hunting dogs. It was more prevalent in the old school GSP breeders but basically the dogs were bred to maximum effectiveness without consideration for the public perception of culling and inbreeding because it doesn't exist in the rural communities here. May be harsh but it works. It's the system that developed the huntaway which is an amazing dog. |
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WildRose
Seymour Texas
MH
Posts:471
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| 10/11/2010 12:30 AM |
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When you look at breeding GSP's consider this. We can produce a new generation every two years, or even less. That means since the inception of the breed we can count over fifty generations.
That means, when you cross for example a dog from Germany to a dog from the US it's quite possible for the two to have no common ancestors for fifty or more generations.
During those fifty generations we have at least fifty opportunities for mutations to be fixed as traits good or bad for each mating parent.
That provides for a great deal of genetic diversity.
Line breeing fixes traits and promotes consistency. That is why a litter of two Registered GSP's is going to produce a much more consistent litter and their offspring when mated to other registered GSP's than you would see if you bred to different breds.
The same works with line breeding much more closely related dogs than just two from the same breed.
If you want to very quickly see improvements or real problems arise to surprise you, then breed only to those that are most distantly related within the breed and that's what you will see.
In terms of humans we consider the mating of pairs as closely or more closely related than second cousins as "inbreeding".
In dogs and livestock we usually consider a father/daughter, son/mother, or full siblings being bred to one another as "inbreeding". Half siblings, or other matings sharing common ancestors, not so closely related but within 4 generations sharing common ancestors, we generally consider to be "line breeding".
Context means everything. |
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There's a reason I like dogs better'n people... . |
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WildRose
Seymour Texas
MH
Posts:471
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| 10/11/2010 12:31 AM |
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| Good looking boy BTW. |
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There's a reason I like dogs better'n people... . |
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pixie bee
MH
Posts:4123
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| 10/11/2010 4:43 AM |
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I follow the FCI standard for bite/teeth.It is all spelled out within the standard. When one considers the job a dog's mouth is required to perform we understand why all teeth and a strong jaw is necessary. A missing P3 may be more significant but if a breeder breeds two dogs with missing P1s this is setting a genetic trait that significantly weakens the jaw.
When evaluating dog's teeth, we need to look at the relationship of all the teeth to each other and the jaw. Ethical breeders do care about dentition and require knowledge about the whole mouth - not just the incisors. It is very easy to just count the number of teeth or evaluate the "bite" of the incisors, but it is only when we look at the overall picture that we can see how genetics is affecting the dentition. The breeder needs to know the number of teeth, the type of bite or how the incisors meet, the relationship of the canine teeth, the premolars, the molars, and the jaw curvature. If there are any genetic inconsistencies, this should be taken into consideration in the breeding program.
A DKs teeth are examined at each test and each zutchschau(conformation rating) and the results marked on the pedigree and recorded in the studbooks as public knowledge.
Great pictures. I just love the beach picture. |
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"Time with my dogs clears my mind, renews my faith, and lets me see the world as it is. My only regret loving dogs as I do, is the misery of their early departure." Robert G. Wehle
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pixie bee
MH
Posts:4123
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| 10/11/2010 4:49 AM |
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RCNZ,
I don't necessarily agree with your theory of relationship of one dog to another.
What is not bred for is typically lost. |
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"Time with my dogs clears my mind, renews my faith, and lets me see the world as it is. My only regret loving dogs as I do, is the misery of their early departure." Robert G. Wehle
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RCNZ
New Zealand
JH
Posts:26
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| 10/11/2010 4:45 PM |
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The FCI standard accepts a dog missing up to 2 PM1s. I agree with the rest of your points but I was referring specifically to missing PM1s that I had witnessed in labs. Looking at the dentition it's hard to see how missing those teeth can significantly weaken the jaw have any effect on performance or health at any point in the dogs life. It seems a shame to me to exclude an otherwise excellent dog for a unimportant deviation. For the record, no none of my dogs are missing any teeth.
Regarding linebreeding and relationships of dogs- Yes there may have been 50 generations of dogs but the distance of a relationship under the right circumstances has no affect. I can imagine some people are rolling their eyes right about now but I'll try to explain.
Looking at the breed history, setting aside some outcrossings behind the barn, all the GSPs in the world evolve from a given group of dogs developed in Germany. At some point in a breed development there is going to be a genetic choke point where the outcrossings to other breeds cease, inbreeding occurs to homogonize the genetics then outcrossing of the lines occurs. The interesting thing about GSPs is that WWII introduced a second choke point where only certain dogs survived.
At that point you've got probably the tightest choke point on the genetics of that breed. The genetics are fixed in these dogs. There are a limited number of dogs in the world and all dogs in the world descend from them. It's safe to say that there was a fair bit of genetic diversity amongst them in terms of the genetic variability that can exist amongst a single breed of dog. However, again ignoring a few outcrossings that may have happened behind closed doors, it is still a small population of dogs with a small amount of genetic variability amongst them in the grand scheme of things.
Efforts since then have reduced, not increased, the genetic variability of the breed. Of those original dogs, only a certain portion passed on their genes at all. Of those genes, some have been eliminated by chance or by selection. The overall population size and number of generations is completely insignificant because genes are passed accurately regardless and barring outcrossing there is no way for new genes to be added. The genes available in the entire population are only the genes that were present in the ancestors. It's a concept called founder effect.
From these genes variability in the breed has arisen, unsurprisingly. Like pixie bee said, if you don't breed for it you lose it. They are the extreme phenotypes arising from the genotypes of the founders of the modern breed. If you eliminate the extremes like the AF trial lines and the show only lines, you create another choke point. If you go even deeper and go type to type you're homogonizing things even more.
Genetic mutations don't factor in. A gene mutation occurs once every 10,000 replications. Of those mutations, most are caught by factors within the cells. A mutation that actually makes it to the genes passed on happens about once every 100,000 times. Of these mutations, most are fatal and thereby somewhat self eliminating. The remainder are things like VWD. I don’t know how many GSPs have been bred in the world but statistically the chances of any mutations occurring at all is extremely low. The chances that a mutation has occurred that affects the animal in any way other than as a harmful recessive like VWD or a propensity to cancer is almost nil. Furthermore the chances that mutations have occurred that increase the genetic variability of the breed to any appreciable level are akin to the chances of throwing a rock in the middle of the Gobi desert and hitting a rainbow trout.
Anyway…my point is that the genetic variability of the breed is fixed. That variability was fixed from a relatively small population and has been further reduced from that point. There are outliers that have deviated from the standard line but if you eliminate them then you are looking at a relatively small set of genes. The size of that genetic variability is debatable but there are ways to cut it down like breeding type to type.
It surely doesn’t disprove any of the standard methodologies, my only point is that people that abhor line breeding are full of crap because it’s all line breeding or more accurately inbreeding unless you are cross breeding.
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pixie bee
MH
Posts:4123
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RCNZ
New Zealand
JH
Posts:26
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| 10/11/2010 5:54 PM |
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Can't speak for anyone else but it's definitely true for me.
Humans and GSPs are not comparable because the timespans, sizes of population and selective pressures are so vastly different.
Neanderthaals were completely gone over 25,000 years ago, had a massive population and originated from a massive population and had selective pressure that encouraged change. The last genetic choke point inducing founder effect in GSPs occured 65 years ago, they have a relatively miniscule population and selective pressure works towards homogeny. That's not to mention that genetic drift in GSPs is immense relative to the ancestors of man. If anything it goes to prove the point. |
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pixie bee
MH
Posts:4123
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| 10/12/2010 7:06 AM |
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Now, we can't help but bring up COI.
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"Time with my dogs clears my mind, renews my faith, and lets me see the world as it is. My only regret loving dogs as I do, is the misery of their early departure." Robert G. Wehle
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RCNZ
New Zealand
JH
Posts:26
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| 10/12/2010 1:01 PM |
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| How do you mean? |
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pixie bee
MH
Posts:4123
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| 10/13/2010 5:34 AM |
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I'm going to give the reader's Digest version.(am I showing my age)
Most traits are not inherited thru a single gene. They are what is called polygenic. Because of this parental contribution can be unequal. (this is what I beleive most people don't know)
IMO, there are 2 keys to breeding - knowing what is there and having a good eye. Making linebreeding an important tool. In linebreeding you have dogs with a sub set of alleles within the breed. New alleles can be aquired - if wanted - thru outcrossing.
COI tells us probabilities of what can be inherited. Basically, the breeders knows what's there and is hoping it will get passed along or eliminated.
In dogs that are 'linebred' after 50 generations with not one dog in common the breeder has a tough time in knowing what the probabilities are of inheriting the good, the bad and the ugly.
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"Time with my dogs clears my mind, renews my faith, and lets me see the world as it is. My only regret loving dogs as I do, is the misery of their early departure." Robert G. Wehle
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RCNZ
New Zealand
JH
Posts:26
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| 10/13/2010 5:51 PM |
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Yeah I understand all that and I don't wholeheartedly believe that inbreeding is an effective and necessary tool but COI is at best a very rough indicator of homozygosity of a dog. Personally I think it's useless number but that's just me.
COI supposedly indicates the chance that any given gene is homozygous by means of an ancestor on both sides of the pedigree. What some people don't know is that COI isn't a number on it's own. It's a relative number. Meaning that the COI indicates homozygosity above the general population. The definition of the general population however is flexible. Any given dog is only susceptible to the sum of the genes of it's ancestors.
Using the number Wildrose gave of 50 generations, that allows for any given modern GSP to have 1,125,899,906,842,624 (2^50) ancestors. To put that number in perspective that's over 168,000 times the human population on earth. The number of actual possible ancestors is somewhere in the neighborhood of 1/3 trillionth of the number of theoretically possible ancestors. In light of those figures it's safe to say that the average GSP is inbred as all get out.
What's more important is that given populations can be made up solely from portions of the original population or could have experienced various genetic choke points along the way. If you look at the COI for a show bred line, a DK bred line and an AF line, they all mean different things. The general rate of homozygosity in these populations can vary hugely and COI as calculated by pedigree is relative to these numbers.
To give an example consider a dog bred from a population that is 70% homozygous and one from a population that is 50% homozygous. To reach the same chance of homozygosity the latter dog would have to have a COI of 40%. A full brother sister mating by comparison would only give you 25%.
The part that really throws a wrench into the works is that homozygosity of a given population cannot be calculated. Just to calculate relative homozygosity, you would need a full pedigree going all the way back to a choke point of common ancestors for two dogs to compare them. To come up with a population number you would need full mapping of the genome and genetic analysis on every dog at every gene, not likely to happen anytime soon.
Compared to the relative homozygosity of the population from which a dog was bred, pedigree based COI is so insignificant it's not even funny. It's a drop in the ocean.
A far, far more accurate way to judge things is to look at the dog and as many relatives as possible and the degree of consistency that you see gives an idea of the homozygosity.
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pixie bee
MH
Posts:4123
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| 10/14/2010 7:42 AM |
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I wouldn't say linebreeding is necessary, but if done correctly it will be effective - a breeder can produce consistant litters with a good degree of predictability.
A buyer will know that that line produces consistently good rears,etc. An important aspect for the breeder is that they will now know what is undesireable in their lines. Dealing with it is a different story,tho.
A selling point for me to be involved with the German system are the records and the conformation ratings. The judges are highly qualified.
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"Time with my dogs clears my mind, renews my faith, and lets me see the world as it is. My only regret loving dogs as I do, is the misery of their early departure." Robert G. Wehle
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RCNZ
New Zealand
JH
Posts:26
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| 10/14/2010 1:03 PM |
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I didn't say line breeding was necessary, I said inbreeding is necessary, mostly to indentify and remove unwanted recessives.
What are the rules for getting into the NADKC tests? Can any GSP test? |
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trueblushorthairs
MH
Posts:129
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| 10/20/2010 8:45 AM |
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| I was a little surprised that no one jumped in and said they believe both inbreeding and linebreeding are necessary. There is no chance to produce consistent animals, whether dogs, horses, cows, without a high level of line breeding and occasional inbreeding. Where it's true that of the thousands of field trial GSPs running in the US, most share high levels of common ancestry. outcrosses to outcrosses to outcrosses never will produce constency. |
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pixie bee
MH
Posts:4123
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| 10/20/2010 9:40 AM |
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This is not entirely true. If a breeder chooses dogs based on phenotype and that compliment each other's shortcomings, there is a good chance the litters will have a few pups that will be consistent and conformationally correct. Getting these pups to reproduce well is more challenging. The more diverse genes in the mix the more challenging it is to know what will be thrown.
It all depends on what a breeder wants. Most breeders want good looking, performing dogs that make the breeder look good and if one makes it big time, well, the litter is considered a success.
Linebreeding is a necessary component in my fututre program, but I don't discount a breeder for not line breeding.
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"Time with my dogs clears my mind, renews my faith, and lets me see the world as it is. My only regret loving dogs as I do, is the misery of their early departure." Robert G. Wehle
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RCNZ
New Zealand
JH
Posts:26
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| 10/21/2010 7:36 PM |
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Yeah trueblusshorthair, I don't necessarily disagree with that statement as a whole but I think it varies widely with the species, breed and most importantly the population within that breed and how two dogs fall within the overall scheme.
In my mind it really comes down to defining terms since everybody could be saying the same thing just interpreting the terms differently.
A great counter argument to your statement is the current state of GSPs in NZ. There's the usual backyard breeders but amongst the serious, competent breeders the pups are remarkably consistent between lines and when crossed. The whole population is more or less one line. It's not line breeding by most definitions but it definitely consistently produces good dogs of a consistent type even where real line breeding or inbreeding isn't used as long as the type is adhered to. |
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