is after the previously written word, of course, the question of whether and how the inbreeding is useful to install in a breeding strategy. If it finds such to demonize Pandora's box that will always by some authors is invoked again? Does it really any good? Or it is the means by which one makes the unsterblichlich as a breeder, because it brings with it extremely rich quality racing pigeons, as once the Janssen brothers.
Well, inbreeding is neither. Inbreeding by itself is considered impossible to evaluate. For it is very important to consider in addition, operated in what degree inbreeding, which is subjected to the breeding selection process, and what we want to achieve with inbreeding.
inbreeding, the way of the degeneration?
increases through progressive levels of inbreeding of homozygous genes steadily. The result can be an inbreeding depression, the performance of the offspring severely impaired. In pigeon racing, there have been a number of famous breeders who have fallen into this "trap" of inbreeding: The Janssen brothers belong to this group, such as Karel Meulemans, Toni von Ravenstein with his Caesar-line, Günter Prange with its pure red Delbar, and some other well-known breeder.
If these kinds of capacities in pigeon racing in the inbred "failed" are, then you should not let the hand off all of the inbreeding? Yes, it is possible to dispense completely inbred. You need to realtiv however, a large stock of pigeons, or you will always a good number of foreign New pigeons into the stock. Because you lead a no animals are after very few generations, most performers used together, one would therefore inbreeding not around, or accepting too much compromise on the selection on the breeding objectives (see Section 7).
On introducing constantly new animals pose this risk with them to introduce new disease germs. In addition to this I think is often overlooked that the imported animals need because of the "unusual" for them microflora several months until they reach the same good health as the rest of the stock animals. In addition, may well be the newly introduced good pigeons, but possibly they do not fit easily with the previous own species. Extensive testing in the discipline here is therefore a must.
As a result of these uncertainties and risks, will run on virtually every shot a little inbreeding. And even Hans Zurhöfer, the devil of the inbred so vehemently, bred relatives 5th Grades and saw therein no more inbred. But the latter is of course, inbreeding, to a lesser extent (inbreeding coefficient of 3.1% in a joint family).
The above breeder examples I have "failed" the word deliberately placed in quotation marks. For ingezüchtetem at Meulemans Stamkoppel young, at the Janssen-pigeons of the 80s and 90s and even in the pure Prange Delbar the present (such as the mother of 802, 665) should not talk about failure! These animals were, if you push them on the journey began, perhaps no longer capable of top performance. But as a sire at crossover pairings have become world famous. Because of their high homozygosity in primarily "good" genes, they are superior in the giving of "good" genes the crossing usually much dust. This is a fact, look through the vigorous opponent of the inbred love of time.
words with a high inbreeding coefficient I buy my secured property inheritance and genes to the offspring with the Price of inbreeding depression. So it is in some ways a trade with the devil, in which one must be very wary. The inbreeding depression is but in a subsequent mating Kreuzung lost.
inbreeding on the "cleaning" of the genetic
In his book "The art of growing," writes Prof. Alfons Anker that inbreeding depression is a more visible evidence of a higher Homozygotiegrad. This thesis was in genetics now clearly refuted. Which genes are homozygous by inbreeding, and whether they thus cause negative or positive depends on the source material is used with the inbred and on chance.
being among the breeding animals that have recessive "harmful" genes in the genome, it could by the inbreeding of course, these genes are concentrated in a homozygous form and develop their harmful effects. Of course this is in no way a quality document (in the sense of high homozygosity) for the breeding animals. Such animals must be selected instead. And also the parents and their offspring are excluded from breeding, as the inbreeding here has proved so, that both father and mother carry the "harmful" gene, which we do not want further spread in the stock.
Thus one can effect the occurrence of these bad qualities hidden by strong inbreeding also aware of use to test the quality of the hidden properties of a line. And you can become virtually "clean" his stock of such genes by removing the entire line. In dog breeding is something quite common in hereditary diseases.
If I run so strong inbreeding on a top-tier, and the offspring know about an average of many shortcomings, not only the inbred offspring is discarded, but we should also abandon its growing aspirations for the future on this "top-tier "to establish !
Do I want to have an estimation of homozygosity, so I should not aussein to inbreeding depression, but rather calculate the inbreeding coefficient. And this is high and the quality of the Dove and their offspring also very high in relation to my breeding goals, then I have a very valuable animal for breeding, because it's good genes with high probability and hence continued to have many offspring.
inbred to the consolidation of new properties
arises when something completely new in the genome, because there happened error when copying of information during meiosis, we speak of mutations. Mutations are very rare. So much so rare that they encounter the most pigeon breeders during their entire breeding career barely. Therefore, they play in the pigeon breeding virtually no role. In breeding the different breeds of pigeons mutations, however, have the essential role played. Whether it be the different color varieties, drawings, thick nose warts belatschte feet, the collar, and much more. All of these features occurred in the form of our wild pigeons, the rock pigeon does not occur.
But when, for example, the recessive characteristic of the collar turned up for the first time, farmers were virtually forced to consolidate this mutation through inbreeding and thus a significant number of pigeons with ruff grow. After all, had related descendants of the first mutant, both carrying the new recessive gene are paired together so that the offspring of a visible Ruff showed. Each subsequent occurrence of the neck brace is virtually the proof of the relationship with the first mutants of both the father and the mother.
The principle of inbreeding in nature is an essential element that contributes to the emergence of new species. Inbreeding has also helped create the rock dove, as it has contributed to the creation of man. Thus, inbreeding is not demonize themselves be deemed harmful or objectionable. In breeding, it serves the important purpose of setting properties in a broader population .
inbreeding Overview
it Applies to solve new tasks is a population with many different alternatives in the genome (possibly heterozygote genomes so) much more adaptable than an inbred population (high homozygosity) with few genetic variants.
In pigeon racing is made in respect of some requirements, such as "fast flying" ever again same problem, where it refers to a similar flight distances. Thus, the inbreeding is to consolidate a valuable tool properties such as the "high air speed" in stock.
However, for inbreeding to both "bad", as well as "good" genes can be enriched. Therefore, inbreeding alone is not a tool that drives us forward. brings only combined with very strict selection of inbred inbred offspring for our breeding goals, the desired enrichment of the "good" genes.
that inbred animals generally for travel or extensive breeding test are useless, have refuted the Janssen brothers-four times. Already the "Oude Merckx" with its 18 1.Konkursen was with an inbreeding coefficient of more than 12.7% inbred stronger than they were a young father-grandson pair. And the "Jonge Merckx" flew with an inbreeding coefficient of 45% and another 15 1.Konkurse. The starting material of Janssens was obviously top notch and largely free of "harmful" genes that would have the strong inbreeding can connect to the fore. Also operated the Janssens (at least in the early years, as well as Prof. anchor) reports a very strict selection in breeding. The Committee on inbred offspring is expected, much higher than the crossing offspring.
inbred animals, however, can lose epistasis effects of vitality and efficiency, without having necessarily the enrichment of "harmful" genes must be the cause. is therefore to be expected at constant inbreeding in the long run without crossing a performance hit, even if ever so strong selection is operating on the breeding goal .
very promising but I believe the strongest exchange of inbreeding, hard Selection and subsequent cross with a completely unrelated line, as well as Günter Prange since the 90 runs.
In the first step promises a strong performance between inbred pigeons (or top-breeders) and her best (in terms of our breeding goals) children or siblings, a high enrichment of genes. The subsequent strong selection remain the inbred animals as possible, many of our "desire genes."
In the last step, the "crossbreeding" of the harmful influence of the great vitality of the homozygosity by crossing with a completely unrelated partner is repealed. Also this Partner might naturally arise from a inbred line, he did not. What is decisive is his equally high quality and its adaptability.
With Passer ability here meant that by pairing the highest possible heterosis effect to be achieved. If this does not happen, so the negative effects of inbreeding depression would be lifted only in part, and the offspring can not play their full genetic Potental. The "genetic distance" (the genetic diversity of the genes of the present homozygous inbred animals) between the mating partners should therefore be large.
Since inbred animals a higher homozygosity have, ensuring a secure transition of part of the "good" genes to the offspring, are drawn from very good breeding animals more resistant good young animals than from crossbred with a lower homozygosity.
Conversely, but also noted, being derived from poor breeding animals more resistant offspring bad!
Inbreeding is useful to increase the predictability of the breeding results. For improving the quality, however, the consistent selection is responsible, not the inbreeding.
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