References of "Abras, Sven"
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See detailAdding value to test-day data by using modified best prediction method
Gillon, Alain ULg; Abras, Sven; Mayeres, Patrick et al

in ICAR Technical Series (2010, November), 14

Computation of lactation yields from test-day data has lost much of its importance for genetic evaluations as the use of test-day models is currently quite widespread. In the other hand its interest for ... [more ▼]

Computation of lactation yields from test-day data has lost much of its importance for genetic evaluations as the use of test-day models is currently quite widespread. In the other hand its interest for intra-farm management is increasing as a base for advanced management tools. The first and principal aim of this study was to develop a method which takes into account advantages and disadvantages of existing methods, and to test its potential to provide useful management tools to dairy farmers. A test-day model with modifications to able daily run and management tools was developed. Because of its similarities with best prediction, the method developed here was called modified best prediction. The second objective was to compare the accuracy of this new method with best prediction and test interval methods. Modified best prediction showed good results for predicting daily yields and was slightly better than best prediction for lactation yields prediction. Management tools obtained with modified best prediction are explained. [less ▲]

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See detailAdding value to test-day data by using modified best prediction method
Gillon, Alain ULg; Abras, Sven; Mayeres, Patrick et al

Conference (2010, June 04)

Computation of lactation yields from test-day data has lost much of its importance for genetic evaluations as the use of test-day models is currently quite widespread. In the other hand its interest for ... [more ▼]

Computation of lactation yields from test-day data has lost much of its importance for genetic evaluations as the use of test-day models is currently quite widespread. In the other hand its interest for intra-farm management is increasing as a base for advanced management tools. The first and principal aim of this study was to develop a method which takes into account advantages and disadvantages of existing methods, and to test its potential to provide useful management tools to dairy farmers. A test-day model with modifications to able daily run and management tools was developed. Because of its similarities with best prediction, the method developed here was called modified best prediction. The second objective was to compare the accuracy of this new method with best prediction and test interval methods. Modified best prediction showed good results for predicting daily yields and was slightly better than best prediction for lactation yields prediction. Management tools obtained with modified best prediction are explained. [less ▲]

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See detailAdding value to test-day data by using modified best prediction method
Gillon, Alain ULg; Abras, Sven; Mayeres, Patrick et al

in Book of Abstracts of the 60th Annual Meeting of the European Association for Animal Production (2009, August)

Computation of lactation yields from test-day yield has lost much of its importance for genetic evaluations as <br />the use of test-day models is rather widespread. At the same time its importance for ... [more ▼]

Computation of lactation yields from test-day yield has lost much of its importance for genetic evaluations as <br />the use of test-day models is rather widespread. At the same time its importance for intra-farm management <br />increases at farms as a base for advanced management tools. The most common official method to compute <br />lactation yield is the Test Interval Method (TIM). Alternative methods for computing cumulated productions <br />were developed. These methods can be considered as improvements of TIM as the interpolation method, <br />or completely different methods as multiple-trait prediction (MTP) and best prediction (BP). Research <br />in this field has shown the potential to compute lactation parameters (e.g., cumulated production) with <br />test-day models. The aim of this study was to develop a new method which takes into account advantages <br />and disadvantages of existing methods, and to test its potential to provide useful tools to help farmers to <br />make management decisions. The second objective was to compare the accuracy and the robustness of this <br />method with those of BP and TIM. Because of its similarities with BP, the method developed here was <br />called mBP, for modified-BP. The main difference from BP is the definition of the standard lactation curve. <br />To minimize bias, components of standard lactation curves proper to each herd are computed jointly with <br />random individual effects. Recently a new version of mBP was tested that puts expectations of constant <br />animal effects to observed average values using Bayesian prediction, a feature also used by MTP. [less ▲]

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See detailValLait - Perspective d’évolution du contrôle laitier en Wallonie (Belgique)
Abras, Sven; Gillon, Alain ULg; Bertozzi, Carlo et al

in 12ièmes Recontres Recherches Ruminants, Paris, les 7 et 8 Décembre 2005 (2005, December)

ValLait est un projet qui vise à optimaliser les valorisations des données récoltées via le contrôle laitier. Ces valorisations reposent sur une régression multiple (“BP”, pour “Best Prediction”) qui ... [more ▼]

ValLait est un projet qui vise à optimaliser les valorisations des données récoltées via le contrôle laitier. Ces valorisations reposent sur une régression multiple (“BP”, pour “Best Prediction”) qui permet d’estimer les productions journalières de lait, de matières grasses et de protéines d’un animal en se basant sur différents effets comme le stade de lactation, la date de vêlage, les historiques de production du troupeau et de la population... En outre, le modèle BP permet également, dès le début de la lactation d’un animal, de prédire ses productions journalières futures. [less ▲]

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See detailPit-I and other somatotrope candidate genes to optimize selection for milk traits in bovine species: the 21 century's strategy.
Parmentier, Isabelle; Gillard, Nathalie; Abras, Sven et al

Poster (2003, February)

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