Genetic parameters between ages for jumping ponies using a structured antedependence model
| Autor: | Crichan, H., Arrialh, L., Sabbagh, M., Ricard, Anne |
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| Přispěvatelé: | Institut Français du Cheval et de l'Equitation, Génétique Animale et Biologie Intégrative (GABI), Institut National de la Recherche Agronomique (INRA)-AgroParisTech |
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: | |
| Zdroj: | Annual Meeting of the European Association for Animal Production 70. Annual meeting of the European Association for Animal Production (EAAP) 70. Annual meeting of the European Association for Animal Production (EAAP), Aug 2019, Ghent, Belgium. 717 p www.eaap2019.org |
| Popis: | International audience; To provide breeding values for ponies in jumping competition, we analysed data from ponies’ official competitions reserved for children. All results in competition from 1996 to 2018 were taken into account involving 73,915 ponies aged 4 to 20 with a sum of 301,453 performances. Annual performances were measured by two traits: (1) logarithm of annual sum of points exponentially distributed according to ranking and technical difficulty of the event (points); and (2) annual summary of ranking based on an underlying liability responsible for ranks (ranking). Pedigree data contained ancestors over four generations with 583,963 ponies and horses. Each ages was considered as a different trait. An animal model with fixed effects of height (2nd order Legendre polynomial), year, and sex was applied. To reduce the number of covariance parameters to be estimated, we used a structured antedependent model. Heritability (h2) for points was 0.24 at 4 years old, 0.34 at 5 and then decreases slowly, at 12, h2=0.25. For ranking, heritability is 0.18 at 4, 0.20 at 5 and go through the same decline as points, at 12, h2=0.16. After 8 years old, genetic correlations between ages were higher than 0.80. They were even higher than 0.90 if the interval between two ages was equal or less than 4 years. The age of 4 years old is a specific trait as heritability and genetic correlations were lower than the others, we obtained correlations from 0.70 to 0.60 between 4 years old and adult ages (8 and more). At adult ages, residual or environmental correlations are influenced mainly by the interval between ages. For points and ranking, at consecutives ages correlation were higher than 0.65, within an interval of 3 years correlation were around 0.3 and decreased with the interval increasing. Here again, young ages (4 and 5) display low correlation with adults ages, less than 0.1. Breeding values are summarized using the first two principal components of the genetic variance covariance matrix. They are now officially published. |
| Databáze: | OpenAIRE |
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