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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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Estimating Genetic Parameters using a Random Regression Model
Published November 24, 2008

One of the most important part of the genetic evaluation using a random regression model is the estimation of variance components. This is the topic of many papers because the large computational costs. We can use restricted maximum likelihood (REML), Gibbs sampling and ℜ method for the estimation of genetic parameters. The variance component...s are necessary to calculate the heritabilities and repeatabilities.
The aim of our paper is to estimate the variance components using a random regression repeatability model from test day data set of Hungarian Holstein-Friesian dairy cows and to analyse the change of additive genetic and permanent environmental variance, heritability and repeatability over lactation.

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Examination of repeatability of ultrasound scanning technique in young bulls
Published November 24, 2008

The author’s goal with the methodology examination was to determine repeatability of taking and evaluating ultrasound images. In the trial an operator person took two images about the ribeye area and rump fat thickness (P8) of every young bull, which were measured by the same person in four repetitions. Also, we had altogether eight images ab...out the same part of the body. Images were collected using Falco 100 (Pie Medical) real-time ultrasonic scanner equipped with an ASP 3,5 MHz, 18 cm linear array transducer.

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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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Opportunities of utilization of real-time ultrasound technique in beef cattle breeding
Published December 21, 2009

The goal of the authors was to evaluate the repeatability and  accuracy of real-time ultrasound technique under Hungarian conditions. Ribeye area was measured at first time on live animals, before the day of slaughtering with Falco 100 ultrasound equipment in Charolais fattening bulls. Ultrasound pictures were traced at two times by the operator. After slaughtering, ribeye area (REA) was measured on the carcass by planimeter at the same anatomical point like ultrasound measurements. Statistical analysis was carried out to examine the relationship between carcass and ultrasound REA. After it, repeatabilty was established by comparing the ultrasound pictures twice.

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