PART XII

OF PEAS AND PUPS

PART XII

INBREEDING/LINEBREEDING

...RUN seems to be the most sought after accessory on the new 1966 Shorthairs. It is but occasionally available as an optional at extra cost and unfortunately, no dealer (breeder) can give it to you with a warranty. Try to buy one and see. There is no doubt that we need added run in the Shorthair, even the average field trial Shorthair. We need more Stamina too, in fact there is little doubt that we will get some added run as we improve stamina too, but we must test (trial) for all the factors which need improvement. We do not test for stamina. There's more to a Shorthair than run...a lot more, lets not go overboard. There's more to a pointer than run...but not so much more.

...RUN WE WANT. It seems logical that the easiest way to get it is to breed a sire and dam that have it. That should give us pups that have it too. The sad fact of the matter that although this is the most common breeding practice among field trailers...the results rarely live up to expectations......Among those who show Shorthairs the same process is followed with the same results. The finest looking bitch is bred tot he finest looking sire (without regard to kinship) and the pups rarely equal the merit of the parents....WHY IS THIS PRACTICE FOLLOWED if the results continually fall below expectations? Because it seems so logical. The breeder is sure that it is merely fate working against him this time, next time will be different, he thinks.

...SELECTION ALONE WILL BRING PROGRESS...it has for 10,000 years. Look at the variety in pure bred dogs. Selection has done most of it, but how much of the progress have you seen? Very little, because selection brings progress at an almost imperceptible rate. It's fine, if you have a couple of hundred years but who has?...We are continuing the work started by the founders of the breed less than 100 years ago and others will follow us. We can make a greater contribution than any who have gone before us and harvest the benefits for the breed and our own enjoyment during our lifetime if we will but try. This selection road alone, is a long slow one because we are not bring to bare, all of the force that modern genetic science has given us...We are crawling when we should be running. Mating the best to the best, is like trying to crawl out of the well. Up two feet, back one. We'll make it if we live long enough. It is a genetic fact of life that random matings tend toward the mean (average) of the breed. If parents are unrelated and superior, the pups will be better than average but below the average of the parents. Up two feet, back a foot. This is the expectation...these are the odds...apparent logic to the contrary not withstanding. This is because the hundreds and hundreds of genes which produce the desired trait...run....in one dog, will rarely come in the same allelic series which produce it in another unrelated dog. We may get a little overlapping but the chances of this taking place are pretty remote because of the number of genes involved, as we shall see under Variation which follows. They just don't double up.

...AMONG RELATED ANIMALS this drag toward the mean is much reduced because the chances of doubling up are greatly increased (see under "full sibs" Fig. 47). For this reason, good running parents usually mean good running pups. Some might run a little better than the parents, some not so well...We do not intimate that mating a closely related pair of good running dogs will produce the next National Champion (although it has more than once) for even when using but 16 gene pairs as in Figure 47, it would be necessary to mate Artus and Becky four or five time to work out all possible combinations but in each of those matings, there could be an overlapping of 31 out of the 32 genes....

With Count X Duchess, there would have to be 3000 matings to accomplish the same results...see all the combinations, and it is altogether possible, that you would get more out of the 3000 matings there, than out of the 44 matings merely because you had more to start with. This is theory, the facts are that related parents with X-amount of run will produce better running pups than unrelated parents with the same amount of run, all other factors being equal, and although the difference may be small, the overall advantage to the breed is great because any little additional run in the inbred/linebred pups is likely to be a gain held by the rachet mechanism of homozygosity. Up two feet, one inch, back not at all.

VARIATION

...VARIETY IS THE SPICE OF LIFE someone once said. It is also the touchstone of the breeders art, since it is necessary to progress. Inbreeding/linebreeding decreases variation. If variation is necessary to progress and inbreeding decreases it, it follows that inbreeding slows progress. Sounds logical. The problem is that we are dealing with so many variables, remember 10³⁰⁰⁰, that to choose wisely among them is almost impossible. It is therefore necessary to reduce them to something we can grasp. We must know what we have before we can improve it. With a variation of only 20 gene pairs, every man, woman and child on the face of the earth could have a Shorthair and it would not be necessary for any two dogs to be the same...that's variety! You have heard about 10,000 monkeys pounding 10,000 typewriters for 10,000 years and not coming up with the Declaration of Independence? They did come up with "Mary had a Little Lamb" but it took four men 18½ years to find it and then it wasn't what they wanted...The "reading" of the genes would be no less impossible without some reduced variation. This is accomplished by building strains and fixing types...by inbreeding, by increasing homozygosity.

(Figure 47)...ABOVE IS DIAGRAMED, using the "beads for genes" idea, a set of genes from a typical sire and dam of the relationship indicated. Artus & Becky are half siblings and are thus related by 25%, that is, they share 25% more homozygous genes (pure alike gene pairs) than do average members of the breed. Referring to Fig. 38, form Part IX shown again.

Count & Duchess are outcrossed and thus share fewer homozygous genes in common than the average. We are talking about only 26 gene pairs, a tiny fraction of the whole. they were picked at random and you may consider that they exercise partial control over some related trait, be it run, angulation, tail set, nose, makes no difference, since the genes function in the same general way. Under "full sibs" we show the number of possible different (genetically different) littermates by the mates with the genotypes listed. For these 16 pairs, Artus & Becky could have only 44 different full sibs an din a single litter it would be possible (5 to 1 against) to have littermates to the same for these few genes...Count X Duchess could have 23,328 genetically different littermates and the odds against having any duplication or doubling up would be somewhere around 300 to 1.......Imagine, 44 to 23,328! Which litter do you suppose showed the most consistency?...Is it any wonder that the odds favoring run in pups of closely related parents of ability, is so much greater than in the pups of unrelated parents of equal ability?...Look under "half sibs". Here, the littermates have the same sire (or dam) either Artus or Count and these sires are bred to all the genetically different bitches in the breed. Again, for these few genes, Artus could produce 201,424 different half sibs, while Count could produce close to a million (834,624), four times as many. WHY IS THIS? because Artus and Becky shared a common sire, they were half sibs to start with and were therefore more Homozygous. Note further that neither sire comes even close to being able to produce the total number combinations for these 16 gene pairs in the whole breed, 43,046,721....Some, will miss the point altogether and say, "Hell no how could any sire produce that may pups? The circumstances are that he cannot do so because he lacks the genotype...not necessarily the virility or the longevity.

...IN SPITE OF THE FACT THAT RUN may be controlled by hundreds and hundreds of genes and we have diagramed but 16 pair, the fundamental action is the same and the difference lies in degree and numerical complexity. Since genetics has not reached a point of specifics, it is only through generalizations that the knowledge can be helpful to the average breeder.

...It is NOT a fact that ALL pups from closely bred, good running parents will run better than their parents. It is NOT a fact that ALL pups from random mated, good running parents will have less run than their parents...."All", "every", "only", do not belong in the genetic vocabulary any more than does "positively" or "absolutely". We are talking about probabilities not certainties. Probabilities only become certainties on a percentage basis over an enormous number of litters. It is improbable that if the world lasts another million or so years that there could ever be an opportunity for the genes of Shorthairs, to assume all of their various possible combinations. 10³⁰⁰⁰? We should be able to get some general information that will be helpful if we study Figure 47. Important points for the breeder to consider are:

1) How variation is reduced by inbreeding and increased by outbreeding (44 to 23,328). So that if you want more or less variation you know, in a general way, how to reach your goal.

2) How any trait you many desire is more likely to come from related parents show possess the trait than from unrelated parents who possess it. This plan is also more effective in correcting defects. That is, mating your little bitch to a related sire who is strong where she is weak, than mating her to an unrelated sire who is strong where she is weak.

3) Why, because so much variation exists even in closely related matings, that ALLELIC series are very unlikely to double up in outbreeding.

4) Why identical pedigrees merely mean SIMILAR, not identical genes.

5) Why increased homozygosis is important and desirable at this stage of Shorthair development.

...From "Our Dogs", the British genetic authority, Dr. E. Fitch Daglish, well-known to the American dog fans through the pages of "Dog World" has this to say about inbreeding: "It is safe to claim that in practice, inbreeding is the only method by which a strain that can be relied upon to breed true to its own type can be evolved. But if anything worthwhile is to be accomplished, care in the choice of all animals used for breeding must be unremitting; selection being exercised in respect to all essential qualities, mental and constitutional as well as physical, and not confined to a few fashionable show points."

DANGERS FROM INBREEDING

...WITH MOST GOOD there comes some evil...roses have thorns. Fire feeds and warms, it also destroys. Because it destroys we do not abandon its use, it has too many benefits. We use it much but we use it cautiously, making every effort to gain its advantages while guarding against its hazards. If our vigilance slackens we are destroyed. Some would prefer not to live so dangerously. Inbreeding can provide just as much comfort and satisfaction as the flame...it can prove equally disastrous, if our vigilance slackens, if our selection weakens.

...IT IS THE SAME FACTOR which brings good and evil from inbreeding. Fortunately, the opportunity for evil is less than that for good WHERE ANIMALS ARE SUPERIOR.....Superior phenotypically, from what we can see. We want them to be genotypically superior too but we only know what we can see and we cannot see the genes....If we inbreed superior phenotypes we are right soon going to know if they are also superior genotypes. The (like) homozygotic tendencies of inbreeding apply equally to detrimental and favorable genes. If poor genes are brought to the surface faster than we can dispose of them, some are going to become established in our strain...Some will imagine that with but a paragraph or two directed at the dangers of inbreeding that they are few or that the author is unaware of them. Neither assumption is true. The dangers are real, just as the dangers of a lighted match are real. There are no dangers if the match are real. There are no dangers if the match is out and dead but there's a very real danger if the match is tossed by the path in the very dry woods. Where the animals are superior, the dangers from inbreeding are more imagined than real. We have tried to explain the mechanism of inbreeding so that the breeder understands the results that cause them....good or bad...Intelligent people don't have to be told not to throw a lighted match or cigarette butt into the forest. Knowledge of fire tells them why. Knowledge of the homozygotic tendencies of inbreeding tell them why only outstanding specimens are inbred.

...LUSH, "Animal Breeding Plans" referred to earlier has this to say, "It seems reasonably certain that more opportunities for breed progress are lost by not inbreeding where inbreeding would be advisable, than are lost by too much inbreeding...When inbreeding becomes too intense, the individual breeder, may lose by that; but the progress of the breed is not apt to suffer. The best of the inbred animals are likely to give good results in outcrosses.@

...Dr. HELEN KING of the WISTAR INSTITUTE, bred rats full brother to sister for 25 generations. Probably getting as close to 100% homozygosity as would be possible in mammals. The strain not only did not degenerate, it prospered! The inbred rats were larger, more healthy, had bigger litters and lived longer than the control strain which were not inbred and lived under the same environment. The success came from rigid selection for the desired traits. Without selection, the strain would probably never have reached the 5^th generation, much less the 25^th.

Copyright 2001. Dr. James G. McCue, Jr. All rights reserved. Postscript: And his legacy lives on in the German Shorthaired Pointers of today. May they always be healthy and bred with forethought and planning.

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