Inbreeding depression is the reduced biological fitness in a given population as a result of inbreeding, or breeding of related individuals. Population biological fitness refers to an organisms ability to survive and perpetuate its genetic material. Inbreeding depression is often the result of a population bottleneck. In general, the higher the genetic variation or gene pool within a breeding population, the less likely it is to suffer from inbreeding depression. Inbreeding depression seems to be present in most groups of organisms, but varies across mating systems. Hermaphroditic species often exhibit lower degrees of inbreeding depression than outcrossing species, as repeated generations of selfing is thought to purge deleterious alleles from populations. For example, the outcrossing nematode (roundworm) Caenorhabditis remanei has been demonstrated to suffer severely from inbreeding depression, unlike its hermaphroditic relative C. elegans, which experiences outbreeding depression. Inbreeding ...
Saha, N.,Hamad, R.E.,Mohammed, S. (1990). Inbreeding effects on reproductive outcome in a Sudanese population. Human Heredity 40 (4) : 208-212. [email protected] Repository ...
8. Inbreeding is expensive. For cows that survive to freshen the first time, each 1% increase in inbreeding reduces lifetime net income by $22 to $24.. 9. There is no magic level of inbreeding that is acceptable. Effects of inbreeding on performance of commercial dairy cattle are almost entirely negative.. 10. Inbreeding decreases performance. Inbreeding decreases cow survival, single lactation production and reproductive performance.. 11. Inbreeding increases negative factors. Inbreeding increases calf mortality, increases age at puberty through retarded growth, and increases rate of disposal or loss of replacement heifers prior to first calving.. 12. Inbreeding should be managed in herd breeding programs rather than avoided.. 13. Inbreeding in offspring differs for each sire-dam combination, making mate assignments important if inbreeding is to be managed properly.. 14. Blanket recommendations of a bull as an "outcross" to groups of cows may not be effective in reducing the impact of ...
MAIWASHE, A.; NEPHAWE, K.A. and THERON, H.E.. Estimates of genetic parameters and effect of inbreeding on milk yield and composition in South African Jersey cows. S. Afr. j. anim. sci. [online]. 2008, vol.38, n.2, pp.119-125. ISSN 2221-4062.. The effect of inbreeding on the 305-d yields of milk, fat and protein, and the percentages of fat and protein in the first three lactations was estimated using records on the South African Jersey cows that participated in the National Dairy Animal Improvement Scheme. Inbreeding coefficients were estimated using the entire pedigree records of the Jersey breed and ranged from 0 to 42%. Data were analyzed using a repeatability animal model. The statistical model included the fixed effects of herd-year-season, age of the cow at calving, calving interval, inbreeding as a discrete or continuous variable and random effects of direct additive genetic, permanent environment of the cow and the residual effects. The multitrait derivative-free REML algorithm was used ...
Inbreeding depression is assumed to be a central factor contributing to the stability of plant mating systems. Predicting the fitness consequence of inbreeding in natural populations is complicated, however, because it may be affected by the mating histories of populations generating variation in the amount of purging of deleterious alleles. Furthermore, the level of inbreeding depression may depend on environmental conditions and the intensity of pollen competition. In a greenhouse experiment comparing four populations of the neotropical vine Dalechampia scandens (Euphorbiaceae), we tested whether inbreeding depression for early-life fitness depended on the inferred mating history of each population, as indicated by genetically determined differences in herkogamy and autofertility rates. We also tested whether the intensity of pollen competition and the level of stress encountered by the seeds and seedlings affected the amount of inbreeding depression observed. Herkogamy was a good predictor of ...
Inbreeding: refers to (preferential) mating between biological relatives. As relatives (i.e., ancestors of the first individuals are shared with those of the second individual), they carry genes which are "identical by descent"; extreme inbreeding: mating between sibs, half-sibs, parent-offspring Outbreeding: (preferential) mating between non-relatives Positive assortative mating: mating among individuals who share particular genes or phenotypes Negative assortative mating: mating among individuals who do not share particular genes or phenotypes Inbreeding Coefficients: Individual inbreeding coefficient (i.e., Pedigree inbreeding): F represents the probability that the offspring is homozygous due to identity by descent (ibd) at a randomly chosen autosomal locus, ranges in value from 0 (no locus ibd) to 1 (all loci ibd). Significant factors for pedigfree inbreeding are Factors which determine the probability that various kinds of individuals will come into contact, e.g., population demography ...
Inbreeding: refers to (preferential) mating between biological relatives. As relatives (i.e., ancestors of the first individuals are shared with those of the second individual), they carry genes which are "identical by descent"; extreme inbreeding: mating between sibs, half-sibs, parent-offspring Outbreeding: (preferential) mating between non-relatives Positive assortative mating: mating among individuals who share particular genes or phenotypes Negative assortative mating: mating among individuals who do not share particular genes or phenotypes Inbreeding Coefficients: Individual inbreeding coefficient (i.e., Pedigree inbreeding): F represents the probability that the offspring is homozygous due to identity by descent (ibd) at a randomly chosen autosomal locus, ranges in value from 0 (no locus ibd) to 1 (all loci ibd). Significant factors for pedigfree inbreeding are Factors which determine the probability that various kinds of individuals will come into contact, e.g., population demography ...
Our 3-year field study (2006-2009) using captive populations of D. melanogaster is the first field study to investigate the relationship between inbreeding depression and seasonal fluctuations in stress level. We found that stress levels were on average fourfold higher in the winter compared with the summer, and that this higher stress level increased the inbreeding depression affecting population productivity from 32 per cent in the summer to 65 per cent in the winter. Moreover, this covariation of stress level and inbreeding depression conformed to the same linear relationship seen in experimental Drosophila laboratory studies of stress and inbreeding (figure 2). The observation that inbreeding depression based on population productivity in the field follows the same relationship as inbreeding depression based on larval survival in the laboratory suggests that even in complex environments stress and inbreeding interact in the same predictable manner. This same general relationship has been ...
Estimating inbreeding coefficients from NGS data: impact on genotype calling and allele frequency estimation [METHOD]: ". Most methods for Next-Generation Sequencing (NGS) data analyses incorporate information regarding allele frequencies using the assumption of Hardy-Weinberg Equilibrium (HWE) as a prior. However, many organisms including domesticated, partially selfing or with asexual life cycles show strong deviations from HWE. For such species, and specially for low coverage data, it is necessary to obtain estimates of inbreeding coefficients (F) for each individual beforecalling genotypes. Here, we present two methods for estimating inbreeding coefficients from NGS data based on an Expectation-Maximization (EM) algorithm. We assess the impact of taking inbreeding into account when calling genotypes or estimating the Site Frequency Spectrum (SFS), and demonstrate a marked increase in accuracy on low coverage highly inbred samples. We demonstrate the applicability and efficacy of these ...
The effect of inbreeding on egg to adult viability was determined for Drosophila virilis over a wide range of inbreeding levels (0 , F ,.734). The quantity -loge (Viability) was found to be a curvilinear function of F, indicating synergistic interaction among loci. The curvature was not evident, however, below F =.500. The values of A and B (Morton et al. 1956) were calculated to be.06 and.77-.86, respectively. This extremely small value of A yielded a very large value for the B/A ratio i.e., 12.51-14.99.. ...
In terms of sexual intercourse, the very last people we think about are our kin. Imagining inbreeding intercourse, whether it involves our closest kin or not, induces aversion in most people who invoke inbreeding depression problems or cultural considerations. Research has focused on the disgust felt when facing inbreeding intercourse between close kin but little is known about other responses. In this study, we considered the influence of fitness costs on aversive reactions by including disgust and emotional reaction as well as moral judgment and attitudes towards inbreeding: higher costs should induce a stronger aversive reaction. The fitness costs were manipulated by two factors: (i) the degree of the participants involvement in the story (themselves, a sib or an unknown individual), and (ii) the degree of relatedness between the two inbreeding people (brother/sister, uncle-aunt/niece-nephew, cousin). To test this hypothesis, 140 women read and assessed different inbreeding stories varying in the
A mating system to reduce the inbreeding of commercial females in the lower level was examined theoretically, assuming a hierarchical breed structure, in which favorable genes are accumulated in the upper level by artificial selection and the achieved genetic progress is transferred to the lower level through migration of males. The mating system examined was rotational mating with several closed sire lines in the upper level. Using the group coancestry theory, we derived recurrence equations for the inbreeding coefficient of the commercial females. The asymptotic inbreeding coefficient was also derived. Numerical computations showed that the critical factor for determining the inbreeding is the number of sire lines, and that the size of each sire line has a marginal effect. If four or five sire lines were available, rotational mating was found to be quite an effective system to reduce the short- and long-term inbreeding of the commercial females, irrespective of the effective size of each sire ...
Supplement Inbreeding is a mode of breeding involving two individuals or organisms that are closely or genetically related. The mating of genetically-related parents would produce progenies with traits of higher predictability. In humans, while inbreeding is acceptable in few certain cultures it is frowned upon largely by others and regarded as taboo. Medically, inbreeding in a consanguineous relationship is discouraged. It is because it increases the tendency of producing offspring with genetic anomalies and congenital birth defects. Inbreeding increases the chances of acquiring deleterious traits. And over time, there would be more individuals with recessive alleles or alleles in homozygous condition. An individual that acquires deleterious traits from inbreeding is referred to as an inbred. In other animals, inbreeding is a common mode of breeding. For instance, the common fruit fly females prefer to mate with their brothers than those who are not their brothers.1 A large gene pool is ...
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The kings of the Spanish Habsburg dynasty (1516-1700) frequently married close relatives in such a way that uncle-niece, first cousins and other consanguineous unions were prevalent in that dynasty. In the historical literature, it has been suggested that inbreeding was a major cause responsible for the extinction of the dynasty when the king Charles II, physically and mentally disabled, died in 1700 and no children were born from his two marriages, but this hypothesis has not been examined from a genetic perspective. In this article, this hypothesis is checked by computing the inbreeding coefficient (F) of the Spanish Habsburg kings from an extended pedigree up to 16 generations in depth and involving more than 3,000 individuals. The inbreeding coefficient of the Spanish Habsburg kings increased strongly along generations from 0.025 for king Philip I, the founder of the dynasty, to 0.254 for Charles II and several members of the dynasty had inbreeding coefficients higher than 0.20. In addition to
Why is self-fertilization in hermaphrodites relatively rare? One hypothesis is that inbreeding load must be low to enable the evolution of selfing (Maynard Smith 1978; Lande and Schemske 1985). Once selfing has evolved, inbreeding load is exposed to purging and should further decline. This is especially true for load caused by recessive mutations with large deleterious effects because of an increase in overall homozygosity levels (Lande and Schemske 1985). These two ideas together predict that selfing populations should have reduced inbreeding load, well below 0.5 (Lande and Schemske 1985). My results for A. lyrata do not support this prediction. Although the inbreeding load was indeed below 0.5 in selfing populations, it was equally low in outcrossing populations.. This finding of low inbreeding load in both selfing and outcrossing populations leads to three important conclusions. First, purging must have been an important force in this system in the past, leading to generally low inbreeding ...
This study of the relative effects of inbreeding and outbreeding on reproduction in the domestic fowl is based on two years observations of triallel matings of hens having an inbred, outbred, and crossbred origin. (P. 529.) Among the many relations established by these observations and reported in the following pages, the data with respect to inbreeding and outbreeding show that: Fertility was influenced indirectly but not directly by the breeding system. Hens of an inbred origin were definitely less fertile than those of an outbred origin, irrespective of the kind of male to which they were mated. (P. 535.) Hatchability decreased with inbreeding of outbred females (F = 0 to F = .25) but did not decrease with further inbreeding of inbred females. Inbred females showed lower hatchability than outbred females whatever the system of mating, but the difference was not statistically significant. (P.
Archiv Tierzucht 54 (2011) 4, 327-337, ISSN 0003-9438 © Leibniz Institute for Farm Animal Biology, Dummerstorf, Germany Genetic variability of traits recorded during 100-day stationary performance test and inbreeding level in Polish warmblood stallions Alicja Borowska1, Anna Wolc1,2 and Tomasz Szwaczkowski1 Department of Genetics and Animal Breeding, Poznan University of Life Sciences, Poznań, Poland, 2Department of Animal Science, Iowa State University, Ames, USA Abstract The objectives of
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An exact recurrence equation for inbreeding coefficient is derived for a partially sib-mated population of N individuals mated in N/2 pairs. From the equation, a formula for effective size (Ne) taking second order terms of 1/N into consideration is derived. When the family sizes are Poisson or equally distributed, the formula reduces to Ne = [(4 - 3 beta) N/(4 - 2 beta)] + 1 or Ne = [(4 - 3 beta) N/(2 - 2 beta)] - 8/(4 - 3 beta), approximately. For the special case of sib-mating exclusion and Poisson distribution of family size, the formula simplifies to Ne = N + 1, which differs from the previous results derived by many authors by a value of one. Stochastic simulations are run to check our results where disagreements with others are involved. ...
The answer is indeed different for different animals so hard to answer this in any quantitative way. However, in basic terms inbreeding (mating among relatives) is more likely to occur as populations become smaller and more fragmented (with reduced dispersal among sub-populations). Often, but not always, inbreeding results in inbreeding depression which is a loss of evolutionary fitness (i.e. higher mortality risk and/or lower reproductive output). This happens because recessive deleterious alleles are more likely to come together in the homozygous state (so that the deleterious effecs are felt) in the offspring of related parents. The amount of inbreedfing depression in a population is therefore dependent on 1) the amount of inbreeding and 2) the load of deleterious mutations in the population. Both of these factors vary a lot among different animal populations.. ...
The answer is indeed different for different animals so hard to answer this in any quantitative way. However, in basic terms inbreeding (mating among relatives) is more likely to occur as populations become smaller and more fragmented (with reduced dispersal among sub-populations). Often, but not always, inbreeding results in inbreeding depression which is a loss of evolutionary fitness (i.e. higher mortality risk and/or lower reproductive output). This happens because recessive deleterious alleles are more likely to come together in the homozygous state (so that the deleterious effecs are felt) in the offspring of related parents. The amount of inbreedfing depression in a population is therefore dependent on 1) the amount of inbreeding and 2) the load of deleterious mutations in the population. Both of these factors vary a lot among different animal populations.. ...
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Yes. Scientists have observed inbreeding in animal species in the wild. This has been observed in mammal, insect and bird species. The effects of inbreeding are quite negative for the animals that engage in it (poor health of newborns, low survival rates) so it is not often observed (and thus it has been difficult to demonstrate the negative effects) in the wild, but it has been done. ...
Estimates of inbreeding and relatedness are commonly calculated using molecular markers, although the accuracy of such estimates has been questioned. As a further complication, in many situations, such estimates are required in populations with reduced genetic diversity, which is likely to affect their accuracy. We investigated the correlation between microsatellite- and pedigree-based coefficients of inbreeding and relatedness in laboratory populations of Drosophila melanogaster that had passed through bottlenecks to manipulate their genetic diversity. We also used simulations to predict expected correlations between marker- and pedigree-based estimates and to investigate the influence of linkage between loci and null alleles. Our empirical data showed lower correlations between marker- and pedigree-based estimates in our control (nonbottleneck) population than were predicted by our simulations or those found in similar studies. Correlations were weaker in bottleneck populations, confirming ...
When two individuals mate, genetic material from both parents is passed on to the progeny. So even if one parent carries a harmful recessive trait, the other parent is likely to have a healthier version, which will manifest itself in the offspring. If both parents, however, carry a recessive allele-which is more likely to happen if they share much of their genetic material, as close relatives do-then they raise the chances that their child will have only the bad genes ...
When a previously stable population undergoes inbreeding, if nothing else changes, natural selection should consist mainly of purging. The joint consequences of inbreeding and purging on fitness vary depending on many factors: the previous history of the population, the rate of increase of inbreeding, the harshness of the environment or of the competitive conditions, etc. The effects of purging were first noted by Darwin[10] in plants, and have been detected in laboratory experiments and in vertebrate populations undergoing inbreeding in zoos or in the wild, as well as in humans.[11] The detection of purging is often obscured by many factors, but there is consistent evidence that, in agreement with the predictions explained above, slow inbreeding results in more efficient purging, so that a given inbreeding F leads to less threat to population viability if it has been produced more slowly.[12] Nevertheless, in practical situations, the genetic change in fitness also depends on many other ...
In line-breeding the idea is to always keep the amount that any one animal contributes to the DNA of any descendent at or below 50%. With inbreeding you regularly will find a higher degree of influence. For instance, a sire/daughter mating will result in an offspring which carries 75% of its DNA from the sire and only 25% from the maternal dam. Interestingly, before the advent of genetic testing for recessive traits the only way to statistically ensure genetic "purity" of a bull/ram/buck etc. was to breed that bull to 35 of his own daughters concurrently. If no genetic defects show up in any of the offspring, the bull is 99.7% likely to be genetic defect free.. In any case, mating two full siblings together does not qualify as inbreeding because the level of influence any one of the grandparents exercises is still only 50% on the individual resultant calf from that full-sib mating.. In conversation with Dr. tatiana Stanton (yes, she spells her given name entirely in lower case) from Cornell ...
ANSWER: Inbreeding is the production of offspring from the mating or breeding of individuals or organisms that are closely related genetically. Inbreeding results in homozygosity, which can increase the chances of offspring being affected by deleterious or recessive traits.
Single nucleotide polymorphism (SNP) genotyping tools, which can analyse thousands of SNPs covering the whole genome, have opened new opportunities to estimate the inbreeding level of animals directly using genome information. One of the most commonly used genomic inbreeding measures considers the proportion of the autosomal genome covered by runs of homozygosity (ROH), which are defined as continuous and uninterrupted chromosome portions showing homozygosity at all loci. In this study, we analysed the distribution of ROH in three commercial pig breeds (Italian Large White, n = 1968; Italian Duroc, n = 573; and Italian Landrace, n = 46) and four autochthonous breeds (Apulo-Calabrese, n = 90; Casertana, n = 90; Cinta Senese, n = 38; and Nero Siciliano, n = 48) raised in Italy, using SNP data generated from Illumina PorcineSNP60 BeadChip. We calculated ROH-based inbreeding coefficients (FROH) using ROH of different minimum length (1, 2, 4, 8, 16 Mbp) and compared them with several other genomic ...
In Focus: Trask, A.E., Bignal, E.M., McCracken, D.I., Monaghan, P., Piertney, S.B. & Reid, J.M. (2016) Evidence of the phenotypic expression of a lethal recessive allele under inbreeding in a wild population of conservation concern. Journal of Animal Ecology, 85, 879-891. In this issue of Journal of Animal Ecology, Trask etal. () report on a strange, lethal, blindness that regularly affects chicks of an endangered bird population. The authors show that the inheritance mode of this blindness disease precisely matches the expectations of a recessive deleterious mutation. Intriguingly, there is also an indication that the disease-causing variant might be maintained in the population by balancing selection, due to a selective advantage for heterozygotes. Could this finding have consequences for conservation actions implemented for the population?. ...
The Hucul horses, native breed of Carpathians, are valued for their strongly consolidated features, like high fertility, fecundity and foaling rate. The relation between the inbred and the reproduction results of Hucul mares was analyzed using two-way ANOVA and one-way ANOVA with regression. The inbreeding level is negatively correlated with fertility and fecundity. Increase of inbred level of 1% causes loss of 0.98% fertility and loss of 1.03% fecundity.
Rare inherited genetic disorders worsened by repeated inbreeding may have brought down the powerful Spanish Habsburg dynasty, Spanish researchers said.
Breeding systems have a dramatic impact on the effectiveness of recombination within plant and animal populations. Parametric estimates of recombination rate in the self-fertilizing species Hordeum vulgare (barley) suggest that a history of inbreeding in the species has not dramatically reduced the amount of recombination or extent of linkage disequilibrium in the species relative to that observed in many outcrossing plant species. The limited impact of inbreeding may result from a relatively recent transition to self-fertilization in barley. By comparing resequencing data in Hordeum bulbosum, a self-incompatible species that is the closest living relative of barley, these researchers hope to determine the likely ancestral levels of recombinational diversity within the lineage. Using resequencing data to estimate both a potential ancestral recombination rate and the divergence time between H. bulbosum and H. vulgare, it will be possible to estimate the transition time of transition to ...
The purebred Shorthorn beef cattle breeding project was continued during 1963 without modification. Inbreeding was continued in the two separate lines, which have remained closed to outside breeding since the study was ...
De Braekeleer, M. (1995). Inbreeding, kinship and surnames in hereditary disorders The experience in Sague-nay-Lac-Saint-Jean (Quebec). Collegium Antropologicum, 19, 289-304.
A genetic change that affects the coded protein (most changes are pretty neutral) is more likely to harm its effectiveness than enhance it. Such changed alleles are recessive, covered up when paired with codes that still produce good working proteins, and random, but passing down a family line. Inbreeding can put together 2 bad recessives - thats why its bad ...
It has long been known that inbreeding is bad for you. A new paper in Nature (Directional dominance on stature and cognition in diverse human populations) finally gives us a good quantitative estimate of just how bad it is. They find that the offspring of first cousins suffer an average reduction of 1.2 cm in…
Talk about blue in the face... Extraordinary story of Appalachias Blue Family whose bodies were discoloured after generations of inbreeding (Daily Mail) And just when was this phenomenon first noticed by the world beyond the familys isolated area? medical explanations, with pictures, at link above
Some animals (such as wolves, lions & elephants) prevent the chance of inbreeding by chasing off the young males as they near maturity, though this may not p...
In his letter of May 26, writer Mel Wolf questions why marriage between same-sex couples should be allowed while marriage between two siblings is not. The answer is, in a word, inbreeding. When two
Early humans who lived around 34,000 years ago recognised the dangers of inbreeding and developed social and mating networks to avoid it, new research has found.
Early humans who lived around 34,000 years ago recognised the dangers of inbreeding and developed social and mating networks to avoid it, new research has...
Researchers calculations suggest that Charles Darwins marriage to a first cousin resulted in a mild degree of inbreeding in their children.
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Further breeding studies were carried out to test the polygenic model for the control of the antibody response to a synthetic polypetide antigen and to examine more closely the nature of the sex influence on the antibody response. The backcrosses of reciprocally mated F1 hybrids into both the highly responding ACI strain of inbred rats and the poorly responding F344 strain yielded offspring with low, moderate and high responses in a ratio compatible with that predicted by the polygenic model. The backcrosses having a low antibody response bred true with inbreeding and with second backcrossing, as predicted, so they apparently have only those genetic factors that lead to a low antibody response. Limited inbreeding studies with the highly responding backcrosses indicated that they also bred true. Inbreeding of moderately responding backcrosses with moderately or highly responding backcrosses gave offspring that showed the whole spectrum of antibody responses, as would be expected for control by ...
Genetic diversity is the key to all genetic progress, past and future. Over the last 10,000 years, poultry was domesticated first from the wild jungle fowl, then in the last 1,000 years into standard breeds. In the last century, those breeds have been further reduced into a few commercially produced types. These lines have since been strongly selected for both growth and egg production among other traits. During this process, genetic variability has been lost at each step. Important issues include: ¿How much variability has been lost¿ and ¿Is there adequate variability to meet future challenges, such as new diseases"? To achieve this goal, a panel of 2551 informative SNPs were genotyped on 2580 individuals including 1440 commercial birds. Allele loss was assessed by determining the relationship with inbreeding, and through the use of SNP ¿weights¿ that correct for ascertainment bias and avoid the need to extrapolate from the inbreeding coefficient. The methods presented are general and ...
Click on queen code shows pedigree, breeding values and inbreeding coefficients.. Licensed queens are marked with -K.. Click on a mating station identifier for more details.. The list of descendents starts with licensed queens and is sorted by association and studbook numbers.. Weighting factors are only displayed of different from the default of the population.. For disease susceptibility the evaluation is as follows: ...
Click on queen code shows pedigree, breeding values and inbreeding coefficients.. Licensed queens are marked with -K.. Click on a mating station identifier for more details.. The list of descendents starts with licensed queens and is sorted by association and studbook numbers.. Weighting factors are only displayed of different from the default of the population.. For disease susceptibility the evaluation is as follows: ...
It does not describe symptoms of Mareks. However, you are working with a bantam breed, Sebrights, that worldwide seem unable to develop an immunity to Mareks. Most breeds can, over many generations, be bred for immunity. (??) How do you know?--Few Vets can test for it, even if it was not a great expense. Inbreeding and close breeding are the best way to obtain any trait that you want to be dominant, simply discarding any birds that show weakness for whatever trait you with to eliminate. It is too bad, but avoiding inbreeding is the slowest way to breed the dominant traits that you want! Keep for breeding, only the strong survivors in your breeding flock (which you may be doing) and breed those birds together, discarding any of their weaker or offspring that display the paralysis. While brother/sister is not first choice--once is OKAY-then breed to cousins, half brothers/sisters, sire or dam. 3 trios can give you breeding birds for YEARS, without obtaining ANY new birds EVER, becomes a personal ...