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by Koach on 29 December 2013 - 09:12
Question for Bebo and Gustav,
Do you not think that since breeding for genotype increases the predictability of the of a future litter's mental and physical characteristics and that breeding for phenotype may require a wait and see period to determine the outcome of the potential of all pups from said phenotype breeding. What I'm getting at here is that if someone wants to buy a 8 week old puppy the odds are in favor of getting a better subject from a good well planned genotype breeding. The phenotype breeding, though it may produce one or two superior subjects would also produce a much more disparate litter of unknown quality and require a longer selection period.
Thanks,
GG
Do you not think that since breeding for genotype increases the predictability of the of a future litter's mental and physical characteristics and that breeding for phenotype may require a wait and see period to determine the outcome of the potential of all pups from said phenotype breeding. What I'm getting at here is that if someone wants to buy a 8 week old puppy the odds are in favor of getting a better subject from a good well planned genotype breeding. The phenotype breeding, though it may produce one or two superior subjects would also produce a much more disparate litter of unknown quality and require a longer selection period.
Thanks,
GG
by ddr gsd on 29 December 2013 - 10:12
Avisak9
by ddr gsd on 29 December 2013 - 10:12
Loren Armour
workingk9.com
workingk9.com
by ddr gsd on 29 December 2013 - 12:12
Hopefully, we will have a few more KNPV enthusiasts, breeders, trainers
and others interested to opine on matters of pedigree/non-pedigree's,
nutrition, and other valuable topics.
Forum member has posted a few questions to certain members, but it is
always a general courtesy to seek and respond in forum membership.
Have we had any KNPV Mali or Dutchie person respond?
and others interested to opine on matters of pedigree/non-pedigree's,
nutrition, and other valuable topics.
Forum member has posted a few questions to certain members, but it is
always a general courtesy to seek and respond in forum membership.
Have we had any KNPV Mali or Dutchie person respond?
by ddr gsd on 29 December 2013 - 12:12
Via PM
www.knpv.nl/landelijk.html
www.knpv.nl/landelijk.html
by ddr gsd on 29 December 2013 - 13:12
Verbatim from website:
"People soon realized that every dog had its own character and thus one dog
can do other and more things than the other dog. This indicates that a trainer
has to adjust his training methods to the dog which has been worked. In the
early 20th century, when this concept was not yet accepted, there was discussion
whether all dogs should be trained with the same "hard" methods or by using
another method which was adapted to the dog. However in which the dogs were
trained, the goal was and still is "to achieve a KNPV certificate that best fits the dog".
"People soon realized that every dog had its own character and thus one dog
can do other and more things than the other dog. This indicates that a trainer
has to adjust his training methods to the dog which has been worked. In the
early 20th century, when this concept was not yet accepted, there was discussion
whether all dogs should be trained with the same "hard" methods or by using
another method which was adapted to the dog. However in which the dogs were
trained, the goal was and still is "to achieve a KNPV certificate that best fits the dog".
by bebo on 29 December 2013 - 14:12
koach,
there are three concepts relevant to the discussion: genotype (hereditary info), phenotype (observed traits such as behavior and development), and phenotypic plasticity. the later being unduly important to the discussion at hand. the concept of phenotypic plasticity captures the degree to which genotype determines phenotype. moreover, low plasticity indicates a high predictability of phenotype from genotype; high plasticity indicates a low(er) predictability of phenotype from genotype. canines are classified as having a relatively high degree of phenotypic plasticity. before i go on, let me provide a minimal but accessible citation list: ostrander & wayne, 'the canine genome', http://genome.cshlp.org/content/15/12/1706.full and dewitt, scheiner, & brody, 'phenotypic plasticity: functional and conceptual approaches' (.e.g, http://goo.gl/q4TqAQ). the dewitt et al text is a quite accessible and comprehensive intro to this topic.
so, the upshot of all this is that phenotypic variance based on a given canine genotype is expected to be rather high. allow me to remove the qualifier 'well planned' from your question and suggest the answer is a resounding no. however, your qualifier is an important one and you'll get it back in a bit :)
consistently and predictably breeding toward a standard, whatever it may be, requires the tightening of phenotypic plasticity in the genotype. 'doubling up', or line-breeding, is a rather common approach to try and achieve this end. the downside of this approach is the inevitable bottle-necking with all its ugly corollaries including health problems. in order to avoid that, you'll see outcrossing, which usually means 'find a phenotypic expression close to the/my ideal/standard based on a different gene base.' while outcrossing reduces genetic bottle-necking issues it increases phenotypic plasticity ... you see the never ending challenge arising to breeders.
breeding by phenotype is generally defined to entail the selection of genotypic expressions that provide a high degree of phenotypic predictability without (heavy) line-breeding. i believe czech and many german, dutch, and belgian breeders refer to that as 'staying within the line.' while their execution of that principle may differ to some degree in the 'bloodline inputs' the core principal remains the same.
regardless, if i see breeders, leave alone a subset of breeders, who manage to produce toward a certain standard in a rather consistent and uniform manner without bottle-necking, i take notice and pay heed. even more so if their genotypic input is widely available.
finally, back to your qualifier 'well planned.' i severely doubt that any breeder that has a track record of consistently producing toward a standard is 'mere' genotype-matching. what in fact is happening, is that expertise is brought to the table that furthers the selection of genotypic expressions believed to bring low phenotypic variability to the mating. so while the answer to your fully qualified question is yes ... it is so because a 'well planned genotypic breeding' is in fact phenotypic breeding.
my initial response was within the context of gsd breeders serving, not necessarily exclusively, the knpv market. there are plenty of 'ipo' gsd breeders that do an awesome job consistently producing dogs that are 'real'. just off the top of my head i'd go just as easily to stefan schaub's vd staatsmacht , otto grasekamp's v stadtfeld, or karl deisenroth's v dunklen zwinger.
there are three concepts relevant to the discussion: genotype (hereditary info), phenotype (observed traits such as behavior and development), and phenotypic plasticity. the later being unduly important to the discussion at hand. the concept of phenotypic plasticity captures the degree to which genotype determines phenotype. moreover, low plasticity indicates a high predictability of phenotype from genotype; high plasticity indicates a low(er) predictability of phenotype from genotype. canines are classified as having a relatively high degree of phenotypic plasticity. before i go on, let me provide a minimal but accessible citation list: ostrander & wayne, 'the canine genome', http://genome.cshlp.org/content/15/12/1706.full and dewitt, scheiner, & brody, 'phenotypic plasticity: functional and conceptual approaches' (.e.g, http://goo.gl/q4TqAQ). the dewitt et al text is a quite accessible and comprehensive intro to this topic.
so, the upshot of all this is that phenotypic variance based on a given canine genotype is expected to be rather high. allow me to remove the qualifier 'well planned' from your question and suggest the answer is a resounding no. however, your qualifier is an important one and you'll get it back in a bit :)
consistently and predictably breeding toward a standard, whatever it may be, requires the tightening of phenotypic plasticity in the genotype. 'doubling up', or line-breeding, is a rather common approach to try and achieve this end. the downside of this approach is the inevitable bottle-necking with all its ugly corollaries including health problems. in order to avoid that, you'll see outcrossing, which usually means 'find a phenotypic expression close to the/my ideal/standard based on a different gene base.' while outcrossing reduces genetic bottle-necking issues it increases phenotypic plasticity ... you see the never ending challenge arising to breeders.
breeding by phenotype is generally defined to entail the selection of genotypic expressions that provide a high degree of phenotypic predictability without (heavy) line-breeding. i believe czech and many german, dutch, and belgian breeders refer to that as 'staying within the line.' while their execution of that principle may differ to some degree in the 'bloodline inputs' the core principal remains the same.
regardless, if i see breeders, leave alone a subset of breeders, who manage to produce toward a certain standard in a rather consistent and uniform manner without bottle-necking, i take notice and pay heed. even more so if their genotypic input is widely available.
finally, back to your qualifier 'well planned.' i severely doubt that any breeder that has a track record of consistently producing toward a standard is 'mere' genotype-matching. what in fact is happening, is that expertise is brought to the table that furthers the selection of genotypic expressions believed to bring low phenotypic variability to the mating. so while the answer to your fully qualified question is yes ... it is so because a 'well planned genotypic breeding' is in fact phenotypic breeding.
my initial response was within the context of gsd breeders serving, not necessarily exclusively, the knpv market. there are plenty of 'ipo' gsd breeders that do an awesome job consistently producing dogs that are 'real'. just off the top of my head i'd go just as easily to stefan schaub's vd staatsmacht , otto grasekamp's v stadtfeld, or karl deisenroth's v dunklen zwinger.
by ddr gsd on 29 December 2013 - 15:12
bebo - You provided scientific facts and statements to back up your point.
It can't get any better than that! You even provided a couple pedigrees
on your example(s).
I've always been enamored by science, art and mathematical probabilities
in a given pedigree. It just continues to get interesting... .
It can't get any better than that! You even provided a couple pedigrees
on your example(s).
I've always been enamored by science, art and mathematical probabilities
in a given pedigree. It just continues to get interesting... .
by Koach on 29 December 2013 - 15:12
bebo,
Thank you very much for your detailed post. I will conserve it within a document and read it a couple of time as well as visit and absorb the information in your references.
Many thanks again for taking the time,
GG
Thank you very much for your detailed post. I will conserve it within a document and read it a couple of time as well as visit and absorb the information in your references.
Many thanks again for taking the time,
GG
by Koach on 29 December 2013 - 15:12
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