فهرست مقالات inbreeding depression

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  1 - Inbreeding Effects on Average Daily Gains and Kleiber Ratios in Iranian Moghani Sheep
  N. Ghavi Hossein-Zadeh
  The objective of the present study was to evaluate the effects of inbreeding on average daily gains and Kleiber ratios in Moghani sheep. Traits included average daily gain from birth to 3 months (ADG1), average daily gain from birth to 6 months (ADG2), average daily gai چکیده کامل

  The objective of the present study was to evaluate the effects of inbreeding on average daily gains and Kleiber ratios in Moghani sheep. Traits included average daily gain from birth to 3 months (ADG1), average daily gain from birth to 6 months (ADG2), average daily gain from 3 months to 6 months (ADG3), average daily gain from 3 months to 9 months (ADG4), average daily gain from 3 months to yearling (ADG5) and corresponding Kleiber ratios (KR1, KR2, KR3, KR4 and KR5, respectively). Data and pedigree information used in this study were collected at the Breeding Station of Moghani sheep during 1987-2005. All the animals were grouped into three classes according to the inbreeding coefficients obtained by their pedigree: the first class included non-inbred animals (F=0%); and the second and third classes included inbred animals (00.10, respectively). There were significant regression coefficients of ADG5 and KR5 on inbreeding of all lambs for changing 1% inbreeding (P<0.01). Indeed, there were significant regression coefficients of ADG3 (P<0.01) and KR3 (P<0.05) on inbreeding of twin-born lambs for a change of 1% in inbreeding. In addition, there were significant regression coefficients of ADG1 (P<0.05) and ADG5 (P<0.05) on inbreeding of male lambs and significant regression coefficient of ADG2 (P<0.05) on inbreeding of female lambs for a change of 1% in inbreeding. Effects of inbreeding on average daily gains and Kleiber ratios in Moghani sheep was not very pronounced in the flock. Planned matings are, however, suggested to avoid accumulation of inbreeding and appearance of its deleterious effects. پرونده مقاله
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  2 - Calculation of Inbreeding Depression Effects on Subclinical Mastitis Using Three Different Models
  س. نقشینه س.ع. رافت غ.ع. مقدم م. ابراهیمی ج. شجاع
  Pedigree information of 3972 Holstein cows and bulls, from 1961 to 2008, was used to calculate inbreeding coefficients and their effects on production traits and subclinical mastitis of dairy farm cows inAzerbaijan province,Iran. Inbreeding was included in a linear mixe چکیده کامل

  Pedigree information of 3972 Holstein cows and bulls, from 1961 to 2008, was used to calculate inbreeding coefficients and their effects on production traits and subclinical mastitis of dairy farm cows inAzerbaijan province,Iran. Inbreeding was included in a linear mixed model as a class variable. Data were analyzed using the PROC MIXED of SAS by MIVQUE method. Results showed that average inbreeding coefficients were inferior in total population and inbred cows (0.8 and 1.3% in total population and inbred cows, respectively). Although the rate of inbreeding coefficients was low, inbreeding had decreasing effects (P<0.01) on milk, fat, and protein yields, while increasing effects (P<0.01) on prevalence of subclinical mastitis. Furthermore, animals with inbreeding coefficients between 0.59 to 1.11%showed a reduction in milk, fat, and protein yields by 2.4, 2 and 2%, respectively; whereas, animals with inbreeding coefficients between 1.11 and 1.75% showed a reduction in milk, fat, and protein yields by 2, 3.7 and 2.7%, respectively. پرونده مقاله
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  3 - Inbreeding and Inbreeding Depression on Body Weight in Iranian Shal Sheep
  ز. پتی‌آبادی ش. ورکوهی س. ساور-سفلی
  The aim of this study was to estimate amount of inbreeding coefficient in Shal sheep and its impact on growth performance. Pedigree information and body weight at different ages (birth weight, 3 month weight, 6 month weight, 9 month weight and 12 month weight) were used چکیده کامل

  The aim of this study was to estimate amount of inbreeding coefficient in Shal sheep and its impact on growth performance. Pedigree information and body weight at different ages (birth weight, 3 month weight, 6 month weight, 9 month weight and 12 month weight) were used from 6692 lambs from 90 rams and 1007 ewes. Data were collected on Ghazvin sheep breeding station during 1997-2013. Estimation of inbreeding coefficient was done by CFC program and quantifying the individual inbreeding regression of traits was run by wombat software. Number of inbred animals at pedigree was 1616 lambs, equal to 24.15% of total population. The average of inbreeding coefficient on whole population and inbred population were 1.51% and 6.28%, respectively. Regression coefficients per 1% inbreeding for birth weight, 3 month weight, 6 month weight, 9 month weight and 12 months weight were estimated as -0.001, -0.017, -0.005, -0.019 and -0.019 kg, respectively. The highest inbreeding coefficient was 31.25% and most of inbred animals had inbreeding coefficients lower than 5%. These results confirmed the low level of inbreeding in the population. Annual trend of inbreeding coefficient on population average was 0.07 and non significant statistically. Applying a designed mating system like cross-breeding could be a suitable method to avoid inbreeding depression. پرونده مقاله
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  4 - Comparision of Direct and Indirect Response to Selection for Breast Weight in Japanese Quail
  م. خالداری ح. قیاسی
  This study was carried out to investigate the direct and indirect responses to selection for four-week body weight (4 week body (wk BW)) and four-week breast weight (4 week breast weight (wk BRW)) and to determine the genetic contribution of reminder founders to the las چکیده کامل

  This study was carried out to investigate the direct and indirect responses to selection for four-week body weight (4 week body (wk BW)) and four-week breast weight (4 week breast weight (wk BRW)) and to determine the genetic contribution of reminder founders to the last generation. A total number of 351 birds were equally allocated to three lines, including two selected lines (S1 and S2 for BW and breast weight, respectively) along with a control (C) line. Total net genetic improvement for BW and BRW in S1 and S2 lines were 31.6, 7.6 and 28.0 and 7.3 g, respectively. Genetic correlations between 4 wk BW and carcass traits (0.85 to 0.95) and phenotypic correlations (0.43 to 0.93) were positively high in S1 and S2 lines. The mean percentage of inbreeding for population and inbred birds in S1 and S2 lines were 0.95, 7.75 and 0.64 and 11.3, respectively. The number of retained founders to the last generation of S1 was more than S2. However, more balance genetic contribution to the last generation was outlined by the founders in S2 line. The BW can be used as a selection criterion to improve the carcass traits because there is a strong correlation between BW and carcass traits, selection for BW is easier to record and also its improvement costs are lower than selection for BRW. Meanwhile, long term response to selection is needed to preserve alleles from the lowest contributed founders. پرونده مقاله