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چکیده
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The aims of this study were the analysis of pedigree information and evaluation of inbreed-ing effects on birth weight (BW), average daily gain from birth to weaning (ADG), weaningweight (WW) and yearling greasy fleece weight (GFW) in Markhoz kids. Mean of inbreed-ing coefficients in whole and inbred populations were estimated to be 2.73% and 5.25%,respectively. Pedigree information over a 23-year period (from 1990 to 2013) was used.Kids born from 2010 to 2013 were considered as reference population. Taking the ref-erence population into account an average inbreeding coefficient of 4.20% was obtained.Average coancestry in the reference population was estimated as 1.93%. Mean of genera-tion interval, computed from four pathways, was 3.55 years, with a longer interval fromdam-progeny pathways relative to sire-progeny ones. Average equivalent complete gener-ation, as a measure of pedigree completeness, in the reference population was 5.84. Realizedeffective population size was estimated from the individual rate in coancestry and from theindividual increase in inbreeding (Fi) as 84 and 69, respectively. The effective numbersof founders, ancestors, founder genomes (founder genome equivalents) and non-foundergenomes for reference population were estimated at 49, 37, 26 and 56, respectively. Approx-imately, 75% of total genetic variation was explained by the 28 most influential ancestors,with a maximum individual contribution of 6.97%. Inbreeding depressions were estimatedfor studied traits by fitting Fiof kids as linear covariates under univariate animal models.Significant individual inbreeding depression was found only for GFW (P < 0.01) as −3.1 gper 1% increase of Fiand not found for other traits (P > 0.05). The effects of inbreedingon estimation of variance components and ranking of animals based on predicted breed-ing values were not significant (P > 0.05). The obtained results revealed the evidences onloss of genetic diversity and bottlenecks in the population, ma
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