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- Bonow, Sandra, et al.
(författare)
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Consequences of specialized breeding in the Swedish Warmblood horse population
- 2023
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Ingår i: Journal of Animal Breeding and Genetics. - : Wiley. - 0931-2668 .- 1439-0388. ; 140, s. 79-91
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Tidskriftsartikel (refereegranskat)abstract
- In many European warmblood studbooks, clear specialization toward either jumping or dressage horses is evident. The Swedish Warmblood (SWB) is also undergoing such specialization, creating a possible need for separate breeding programs and a discipline-specific Young Horse Test (YHT). This study investigated how far specialization of the SWB breed has proceeded and the potential consequences. Individuals in a population of 122,054 SWB horses born between 1980 and 2020 were categorized according to pedigree as jumping (J), dressage (D), allround (AR), or thoroughbred (Th). Data on 8,713 J horses and 6,477 D horses assessed for eight traits in YHT 1999-2020 were used to estimate genetic parameters within and between J and D horses and between different periods. Future scenarios in which young horses are assessed for either jumping or dressage traits at YHT were also analyzed. More than 80% of horses born in 1980-1985 were found to be AR horses, while 92% of horses born in 2016-2020 belonged to a specialized category. The average relationship within J or D category was found to increase during the past decade, whereas the relationship between these categories decreased. Heritability estimates for gait traits were 0.42-0.56 for D horses and 0.25-0.38 for J horses. For jumping traits, heritability estimates were 0.17-0.26 for J horses and 0.10-0.18 for D horses. Genetic correlations between corresponding traits assessed in J and D horses were within the range 0.48-0.81, with a tendency to be lower in the late study period. In the future scenarios, heritability and genetic variance both decreased for traits that were not assessed in all horses, indicating that estimation of breeding value and genetic progress for these traits could be affected by a specialized YHT. However, ranking of sires based on estimated breeding values (EBVs) and accuracy of EBVs was only slightly altered for discipline-specific traits. With continued specialization in SWB, specialization of the YHT should thus be considered.
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| 2. |
- Philipsson, Jan, et al.
(författare)
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Genetic connectedness between seven European countries for performance in jumping competitions of warmblood riding horses
- 2009
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Ingår i: Livestock Science. - : Elsevier BV. - 1871-1413 .- 1878-0490. ; 120, s. 75-86
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this Study was to evaluate the genetic connectedness between seven European populations of show jumping horses. Data on stallions bred for jumping and their pedigree Lip to three generations were provided by seven countries, including 63 17 stallions and 22 324 different horses. Four different methods were used to estimate the genetic connectedness. Common stallions between countries varied from 0 to 309 and common horses from 130 to 1166. "Genetic similarities" were not the optimal measure of connectedness as number of progeny by Country by stallion was not balanced. Correlation between estimates of country effects was computed in a mixed model including the genetic value of horses (h(2) =0.20, all relationships included). For Germany, Belgium, France and The Netherlands, these correlations were 0.32 to 0.51 corresponding to a balanced scheme with I I to 19 progeny per stallion per country. Other correlations ranged from 0.08 to 0.27. Another method to evaluate the connectedness was (i) to Simulate a systematic difference between the true genetic level of countries, (ii) performing a BLUP and (iii) measuring the percentage of the initial difference that Could be found between the estimated genetic levels of the corresponding countries. In 50% of the country pairs, 50% or more of the initial genetic difference was estimated. It was concluded that the genetic connectedness will allow the estimation of genetic correlations. (c) 2009 Elsevier B.V. All rights reserved.
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| 4. |
- Thorén Hellsten, Emma, et al.
(författare)
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Avelsindex för 2013 är här
- 2013
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Ingår i: Nyheter från ASVH. ; , s. 1-
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Annan publikation (populärvet., debatt m.m.)
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| 5. |
- Thorén Hellsten, Emma, et al.
(författare)
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Bra avelsresultat för unga hopphingstar
- 2013
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Ingår i: Ridsport. - 0345-973X. ; , s. 54-
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- De nya avelsindexen för hingstar i svensk varmblodsavel är här - ovanligt tidigt i år. De inkluderar avkommornas tävlingsresultat till och med den 6 oktober 2013 och resultat från unghästtesterna till och med 2013.
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