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Random regression models for genetic evaluation of performance of the Hungarian show-jumping horse population
Published April 23, 2014

The aim of the study was to estimate genetic parameters for show-jumping competition performance using random regression model. Show-jumping competition results collected between 1996 and 2009 were analyzed. The database contained 272 951 starts of 8020 horses. Identity number and gender of the horse, rider, competition date, the level of the c...ompetition and placing were recorded in the database. Competition levels were categorized into five groups. Weighted – competition level used – square root transformed placing was used to measure performance of horses. The random regression model included fixed effects for gender, year and place of competition, and random effects for rider, animal and permanent environment.

Later performance of show-jumping horses measured with weighted square root ranks is less influenced by rider and permanent environmental effects than performance at the beginning of a horse’s sporting career. Heritability increased continuously from 6.3 years of age (2296 age in days), values were in the range of 0.07 and 0.37. Higher heritability was found in later ages. Weak genetic and phenotypic correlation was found between the early 4–5–6 years of age and older (7, 8, 8+) age classes. From 8.5 years of age (3132 days old) there were strong genetic and phenotypic correlations between neighboring age groups. For the same age classes moderate and strong genetic and phenotypic correlation was found. Genetic correlation between 13.5 years of age and older horses was very strong.

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Evaluation of Hungarian show-jumping results using different measurement variables
Published May 6, 2013

...5); font-variant-ligatures: normal; font-variant-caps: normal; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">The aim of the study was to compare different fitted models for show-jumping results of sporthorses and to estimate heritability and repeatability value. Show-jumping competition results collected between 1996 and 2011 were analyzed. The database contained 358 342 starts of 10 199 horses. Identity number, name and gender of the horse, rider, competition year, the level and location of the competition and placing were recorded in the database. To measure performance of horses, placing, number of starters and competition level were used. Competitions were categorized into five groups based on their difficulty level. The used repeatability animal model included fixed effects for age, gender, competition place, year of competition (and competition level in case of non-weighted measurement variables), and random effects for rider, animal and permanent environment effect. Variance components were estimated with VCE-6 software package. The goodness-of-fit of the models was low and moderate. Heritability and repeatability values were low for each measurement variables. The best goodness-of-fit model the weighted square root of placing resulted the highest heritability and repeatability value h2=0.074 and R=0.296.

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Coincidences between molecular genetic and studbook data of gidrán mare families on the basis of mtDnA
Published March 24, 2015

The traditional Hungarian horse breed, Gidran has been close to the edge of extinction several times. Despite the multiple bottleneck effect, the breed has retained a part of its genetic variability, and performed prominently in carriage driving and show-jumping competitions. Maintaining of the Gidran breed is important in the point of view of heritage; because besides Hungary, smaller Gidran populations exist only in Bulgaria and Romania. Taking advantage of the special inheritance features of mtDNA, our study focused on two mtDNA regions of Gidran mares. Altogether, 251 hair samples from various Hungarian studs were examined. The analysis was successfully made in case of 251 samples of the cytochrome b and in case of 246 samples of D-loop regions. Because of the distinct mutation rates of the two mtDNA markers, the number of the haplotypes and the way of grouping samples into haplotypes was different. Our key finding was that most haplotypes may be compatible with mare families of the stud book; however incidental mistakes in stud book have occurred only in a few cases. Our results indicate the importance of the preservation and breeding those mare families, which are molecular genetically more diverse than the others, and are in the edge of extinction.

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Analysis of show-jumping results with different measure variables
Published November 24, 2008

The aim of this paper is to estimate heritabilities and to  compare different fitted models for Hungarian Sporthorse showjumping results. Our analysis is based on the show-jumping results between 1996 and 2004. The repeatability animal model for the evaluation of the test results included the fixed effects of gender, breeder, rider, age, y...ear of competition, type of competition, height of fence and number of starters. Variance and covariance components were estimated with VCE-5 software package. Fitting of the models were evaluated with log-likelihood values and Akaike’s information criterion (AIC). Heritability was low in all cases.
The lowest goodness-of-fit model was height of fence-error score and the best-fitting genetic model based on AIC was model using cotangent transformation.

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