فهرس المقالات Baluchi sheep

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  1 - Estimation of Effective Population Size and Genomic Inbreeding Coefficients in Baluchi Sheep Using Genome-Wide Single Nucleotide Polymorphisms (SNPs)
  م. پسندیده م. قلی زاده ق. رحیمی میانجی
  The aim of this study was to estimate the effective population size (Ne) and genomic inbreeding coefficients in 96 Baluchi sheep genotyped using Illumina OvineSNP50 BeadChip. Using NEESTIMATOR software, the estimation of contemporary Ne based on heterozygote-excess and أکثر

  The aim of this study was to estimate the effective population size (Ne) and genomic inbreeding coefficients in 96 Baluchi sheep genotyped using Illumina OvineSNP50 BeadChip. Using NEESTIMATOR software, the estimation of contemporary Ne based on heterozygote-excess and linkage disequilibrium (LD) methods was obtained 15 and 25, respectively. The historical Ne estimated with SNeP software showed a fast decreasing trend over the last 1000 generations. The Ne estimate for the previous 4 generations was ranged from 48 to 75. Three estimates of inbreeding coefficients including genomic relationship matrix (FGRM), excess of homozygosity (FHOM) and correlation between uniting gametes (FUNI) were calculated using GCTA software. The values of FGRM, FHOM and FUNI were calculated the same at -0.017. The average expected and observed heterozygosity using PLINK software were calculated as 0.374 and 0.383, respectively. Our results showed a considerable genetic variation in Baluchi sheep, however the low values of Ne emphasize that measures should be taken to avoid a further reduction in the effective population size. The results of this study provide guidance for future sheep breeding to increase the conservation activities of the native sheep breeds. تفاصيل المقالة
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  2 - Genetic Evaluation of some Carcass Characteristics Assessed by <i>in vivo</i> Real Time Ultrasonography in Baluchi Sheep
  ع. محمدی س. حسنی س. زره داران م. باقری ع. میرشاهی
  In order to evaluate carcass characteristics of a nucleus flock of Baluchi sheep, in vivo ultrasound technique was used to measure backfat thickness (UBFT) and longissimus dorsi muscle area (ULMA) and also to estimate genetic parameters for these ultrasonic traits and l أکثر

  In order to evaluate carcass characteristics of a nucleus flock of Baluchi sheep, in vivo ultrasound technique was used to measure backfat thickness (UBFT) and longissimus dorsi muscle area (ULMA) and also to estimate genetic parameters for these ultrasonic traits and live weights in different ages. The data were collected from 576 animals during 2011. (Co)variance components were estimated by univariate and bivariate animal models using restricted maximum likelihood and Asreml software. Females had higher UBFT and ULMA than males. Estimates of direct heritabilities were 0.32, 0.23, 0.27, 0.02, 0.12, 0.22 and 0.18 for UBFT, ULMA, birth weight (BW0), weaning weight (BW3), 6 month weight (BW6), 9 month weight (BW9) and yearling weight (BW12), respectively. There were positive and high genetic (0.68&plusmn;0.15) and phenotypic (0.62&plusmn;0.03) correlations between UBFT and ULMA. The genetic correlations among ultrasonic and pre 6 month weights were positive and low except for BW0 and ULMA (0.39&plusmn;0.28). Contrarily, moderate to high positive genetic correlations between ultrasonic traits and weaning and post-weaning weights were found (0.33 to 0.61). Phenotypic correlations between ultrasonic and growth traits were positive and ranged from 0.09 to 0.37. High positive genetic correlation between UBFT and ULMA suggests that selection for larger muscle mass result in higher fat carcasses. تفاصيل المقالة
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  3 - Genetic Analysis of Ewe Productivity Traits in Baluchi Sheep
  م. جعفراوغلی ع. صفری ع.ا. شادپرور ن. قوی حسین-‌زاده
  The present study was carried out to estimate (co)variance components and genetic parameters for some productivity traits of Baluchi ewes. The data were collected during a 31 year period (1984-2014) at the experimental breeding station of Baluchi sheep, which is located أکثر

  The present study was carried out to estimate (co)variance components and genetic parameters for some productivity traits of Baluchi ewes. The data were collected during a 31 year period (1984-2014) at the experimental breeding station of Baluchi sheep, which is located in north-east of Mashhad, Iran. The analysis was based on 14030 records of lambs and 4371 records of ewes. Investigated traits were litter size at birth (LSB), litter size at weaning (LSW), litter mean weight per lamb born (LMWLB) and litter mean weight per lamb weaned (LMWLW) as basic traits, total litter weight at birth (TLWB) and total litter weight at weaning (TLWW) as composite traits. Genetic analysis of the studied traits was performed applying restricted maximum likelihood (REML) procedure by fitting a linear mixed animal model. Direct heritability estimate for LSB, LSW, LMWLB, LMWLW, TLWB and TLWW were 0.10, 0.08, 0.13, 0.07, 0.12 and 0.05, respectively. Corresponding values for repeatability estimates were 0.18, 0.17, 0.19, 0.15, 0.18 and 0.15, respectively. Direct genetic correlation estimates among the studied traits varied from -0.52 for LSW and LMWLB to 0.99 for TLWB and TLWW. Phenotypic and environmental correlation estimates were generally lower than those of genetic ones. Although low direct heritability&rsquo;s were estimated for the reproductive traits, as these traits are of interest then they used as the primary selection criterion to bring about genetic improvement in ewe productivity traits. تفاصيل المقالة