References of "Gengler, Nicolas"
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See detailConsequences of selection for milk quality and robustness traits
Bastin, Catherine ULg; Berry, D.P.; Coffey, M.P. et al

in Interbull Bulletin (2012), 44

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See detailIs It Possible to Define a European Total Merit Index?
Vanderick, Sylvie ULg; Faux, Pierre ULg; Gengler, Nicolas ULg

in Interbull Bulletin (2012), 44

Developing a common European bull list is an objective of the PROTEJE (PROduction Traits European Joint Evaluation) workgroup started in 2001 as an initiative of the European Holstein herdbooks. Six Total ... [more ▼]

Developing a common European bull list is an objective of the PROTEJE (PROduction Traits European Joint Evaluation) workgroup started in 2001 as an initiative of the European Holstein herdbooks. Six Total Merit Indexes were compared to define a common breeding goal across Europe. A principal component analysis was used to observe the direction of the largest common variation among the studied Total Merit Indexes. Results showed that the considered indexes had a lot in common. The first principal component explained 86% of the total variation. Based on previous researches establishing combined proofs on a European phantom scale for most traits and trait groups and using a multiple regression for this European Total Merit Index, relative emphases on production and functionality of 37% and on conformation of 26% could be established. [less ▲]

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See detailMid-infrared predictions of cheese yield from bovine milk
Vanlierde, Amélie ULg; Soyeurt, Hélène ULg; Anceau, Christine ULg et al

Conference (2011, August 31)

Economically, cheese yield (CY) is very important. Todate, empirical or theoretical formulae allow estimating the theoretical CY from milk fat and casein or protein content of milk. It would be ... [more ▼]

Economically, cheese yield (CY) is very important. Todate, empirical or theoretical formulae allow estimating the theoretical CY from milk fat and casein or protein content of milk. It would be interesting to predict CY during milk recording directly without the need to estimate milk components. Through the BlueSel project, 157 milk samples were collected in Wallonia from individual cows and analyzed using a mid-infrared (MIR) MilkoScanFT6000 spectrometer. Individual laboratory cheese yields (ILCY) were determined for each sample and expressed as g of dry coagulum/100 g of milk dry matter. An equation to predict ILCY from MIR was developed using partial least squared regression (Winisi III). A first derivative pre-treatment of spectra was used to correct the baseline drift. To improve the repeatability of the spectral data, a file which contained the spectra of samples analyzed on 5 spectrometers was used during the calibration. During calibration, 23 outliers were detected a nd removed from the calibration set. The ILCY mean of the final calibration set was 63.9% with a SD of 11.2%. The calibration (C) coefficient of determination (R²) was equal to 0.76 with a standard error (SE) of calibration of 5.5%. A full cross-validation (CV) was preformed to assess the robustness. R²cv was 0.72 with a SECV of 6.0%. The similarity between R²c and R²cv as well as between SEC and SECV permits to consider robustness of the developed equation as good. Even if it is planned to improve the equation with additional samples, this first equation will permit to study ILCY in the Walloon dairy cattle. [less ▲]

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See detailWhen MIR spectrometry helps to promote a local and vulnerable breed
Colinet, Frédéric ULg; Dehareng, Frédéric; Dardenne, Pierre et al

Poster (2011, August 31)

The dual purpose Belgian Blue breed (DP-BB) is a vulnerable breed rooted in the tradition of the Walloon Region of Belgium. DP-BB has interesting features (e.g. robustness, good longevity and ease of ... [more ▼]

The dual purpose Belgian Blue breed (DP-BB) is a vulnerable breed rooted in the tradition of the Walloon Region of Belgium. DP-BB has interesting features (e.g. robustness, good longevity and ease of calving). Due to its dual purpose type, income generated by both milk and meat is more stable and more flexible in responding to market fluctuations. Registered DP-BB cows are milk recorded (one of the conditions for them to be registered as DP-BB and therefore to get AEM subsidies). Since near 4 years, during routine milk recording, nearly all mid-infrared (MIR) spectra generated at the milk labs and the information of test-day records were collected in a database. Calibration equations using the MIR spectrometry were developed permitting the prediction of several bovine milk components (e.g., fatty acids (FA)). Their application on the MIR spectral database would allow comparing milk composition from 920 DP-BB and 52,497 Holstein cows (selected cows had a proportion of Holstein or DP-BB in their breed composition of at least 90%). On average, each cows had 6 test-day records with MIR spectra in the database. MIR predictions were analyzed using GLM procedure with 5 fixed effects (breed, herd, lactation number, month of test-day recording and lactation stage); values presented are lsmeans (± s.e.) of the breed. Although milk and fat yields were lower for DP-BB, their FA proportions in fat were different from Holstein. Indeed, there are 66.0% (0.2) and 67.6% (0.0) of saturated FA in fat of milk for DP-BB and Holstein, respectively. Furthermore, the DP-BB milk fat was richer in omega-9 (20.7% (0.2) vs. 19.6% (0.0) for DP-BB and Holstein, respectively). Use of MIR predictions may help stakeholders to promote milk and future dairy products from DP-BB. [less ▲]

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See detailIntegration of foreign breeding values for stallions into the Belgian genetic evaluation for jumping horses
Vandenplas, Jérémie ULg; Janssens, Steven; Gengler, Nicolas ULg

Poster (2011, August 30)

The aim of this study was to test the integration of foreign estimated breeding values (EBV) for stallions into the Belgian genetic evaluation for jumping horses. Belgian breeders import horses from ... [more ▼]

The aim of this study was to test the integration of foreign estimated breeding values (EBV) for stallions into the Belgian genetic evaluation for jumping horses. Belgian breeders import horses from neighbouring countries for which foreign information is needed as prior to estimate a more accurate EBV. The Belgian model is a bivariate repeatability BLUP animal model. For the year 2009, pedigree and data files contained 101 382 horses and 712 212 performances. 98 French and 67 Dutch stallions were selected and their foreign EBVs were converted into Belgian national trait. Associated reliabilities were also estimated. A Bayesian approach (Legarra et al., 2007) was applied to integrate this prior information into the Belgian evaluation. It led to a slight modification of the average EBV and of the standard deviation for the whole population. It also led to a new Belgian ranking of the foreign stallions more similar to foreign rankings. However, the adequacy of the Belgian model was not damaged. With regards to prediction ability, Bayesian evaluations using conversion equation estimated by Weighted Least Squares procedure predicted the best traditional EBVs of the year 2009 for the French stallions. For the Dutch ones, it were the evaluations associated to the conversion equation based on Wilmink et al. (1986). For both countries, Bayesian evaluations using conversion equation based on Goddard (1985) improved the most the stability of EBVs. Finally, integration of French and Dutch information improved reliabilities of the Bayesian EBVs of at least 5% and 2% for French and Dutch stallions, respectively. These results confirm the interest to integrate foreign information into the Belgian evaluation for jumping horses. [less ▲]

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See detailEstimating myostatin gene effect on milk performance traits using estimated gene content for a large number of non-genotyped cows
Buske, Bernd; Vanrobays, Marie-Laure ULg; Szydlowski, Maciej et al

Conference (2011, August 29)

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See detailIs It Possible to Define a European Total Merit Index? (Presentation for the PROTEJE group)
Vanderick, Sylvie ULg; Faux, Pierre ULg; Gengler, Nicolas ULg

Conference (2011, August 27)

Possibility of having one common european list of bulls was investigated by principal component analysis (PCA) on 6 european nationals total merit indexes (TMI). Results showed that a european TMI can ... [more ▼]

Possibility of having one common european list of bulls was investigated by principal component analysis (PCA) on 6 european nationals total merit indexes (TMI). Results showed that a european TMI can never completely replace national TMIs, since they represent local differences. [less ▲]

Detailed reference viewed: 18 (6 ULg)
See detailMid-infrared predictions of cheese yield from bovine milk
Vanlierde, Amélie ULg; Soyeurt, Hélène ULg; Anceau, Christine ULg et al

in Book of Abstracts of the 62nd Annual Meeting of the European Association for Animal Production (2011, August)

Economically, cheese yield (CY) is very important. Todate, empirical or theoretical formulae allow estimating the theoretical CY from milk fat and casein or protein content of milk. It would be ... [more ▼]

Economically, cheese yield (CY) is very important. Todate, empirical or theoretical formulae allow estimating the theoretical CY from milk fat and casein or protein content of milk. It would be interesting to predict CY during milk recording directly without the need to estimate milk components. Through the BlueSel project, 157 milk samples were collected in Wallonia from individual cows and analyzed using a mid-infrared (MIR) MilkoScanFT6000 spectrometer. Individual laboratory cheese yields (ILCY) were determined for each sample and expressed as g of dry coagulum/100 g of milk dry matter. An equation to predict ILCY from MIR was developed using partial least squared regression (Winisi III). A first derivative pre-treatment of spectra was used to correct the baseline drift. To improve the repeatability of the spectral data, a file which contained the spectra of samples analyzed on 5 spectrometers was used during the calibration. During calibration, 23 outliers were detected a nd removed from the calibration set. The ILCY mean of the final calibration set was 63.9% with a SD of 11.2%. The calibration (C) coefficient of determination (R²) was equal to 0.76 with a standard error (SE) of calibration of 5.5%. A full cross-validation (CV) was preformed to assess the robustness. R²cv was 0.72 with a SECV of 6.0%. The similarity between R²c and R²cv as well as between SEC and SECV permits to consider robustness of the developed equation as good. Even if it is planned to improve the equation with additional samples, this first equation will permit to study ILCY in the Walloon dairy cattle. [less ▲]

Detailed reference viewed: 32 (6 ULg)
See detailIntegration of foreign breeding values for stallions into the Belgian genetic evaluation for jumping horses
Vandenplas, Jérémie ULg; Janssens, Steven; Gengler, Nicolas ULg

in Book of Abstracts of the 62nd Annual Meeting of the European Federation of Animal Science (2011, August)

The aim of this study was to test the integration of foreign estimated breeding values (EBV) for stallions into the Belgian genetic evaluation for jumping horses. Belgian breeders import horses from ... [more ▼]

The aim of this study was to test the integration of foreign estimated breeding values (EBV) for stallions into the Belgian genetic evaluation for jumping horses. Belgian breeders import horses from neighbouring countries for which foreign information is needed as prior to estimate a more accurate EBV. The Belgian model is a bivariate repeatability BLUP animal model. For the year 2009, pedigree and data files contained 101 382 horses and 712 212 performances. 98 French and 67 Dutch stallions were selected and their foreign EBVs were converted into Belgian national trait. Associated reliabilities were also estimated. A Bayesian approach (Legarra et al., 2007) was applied to integrate this prior information into the Belgian evaluation. It led to a slight modification of the average EBV and of the standard deviation for the whole population. It also led to a new Belgian ranking of the foreign stallions more similar to foreign rankings. However, the adequacy of the Belgian model was not damaged. With regards to prediction ability, Bayesian evaluations using conversion equation estimated by Weighted Least Squares procedure predicted the best traditional EBVs of the year 2009 for the French stallions. For the Dutch ones, it were the evaluations associated to the conversion equation based on Wilmink et al. (1986). For both countries, Bayesian evaluations using conversion equation based on Goddard (1985) improved the most the stability of EBVs. Finally, integration of French and Dutch information improved reliabilities of the Bayesian EBVs of at least 5% and 2% for French and Dutch stallions, respectively. These results confirm the interest to integrate foreign information into the Belgian evaluation for jumping horses. [less ▲]

Detailed reference viewed: 113 (14 ULg)
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See detailConsequences of selection for milk quality and robustness traits
Bastin, Catherine ULg; Berry, D. P.; Coffey, M. P. et al

Conference (2011, August)

Detailed reference viewed: 21 (12 ULg)
See detailPrediction of cow pregnancy status using conventional and novel mid-infrared predicted milk traits
Hammami, Hedi ULg; Bastin, Catherine ULg; Gillon, Alain et al

in Book of Abstracts of the 62nd Annual Meeting of the European Association for Animal Production (2011, August)

The objective of this study was to determine the ability of conventional milk cow characteristics and novel traits predicted by mid infrared (MIR) obtained from milk recording to predict the pregnancy ... [more ▼]

The objective of this study was to determine the ability of conventional milk cow characteristics and novel traits predicted by mid infrared (MIR) obtained from milk recording to predict the pregnancy status once the cow was inseminated. Conventional milk recording, spectral, and reproductive data collected in Luxembourg Hoslteins between 2008 and 2010 were used. Cows were defined as pregnant if they were positively checked and calved between 267 and 295 d later after the last AI or if they had calved between the later intervals when no checks were recorded. Pregnant or not within 3 intervals after last AI (<=35 d, 45-60 d, and 60-90 d) was modeled using logistic regression models firstly as a function of conventional cow milk characteristics and extended to fatty acids as novel traits predicted by MIR in a second step. The lactation curve characteristics for milk, fat, protein, and lactose yields were estimated using modified best prediction method. Test-day fatty acid contents were estimated from collected MIR spectra using an appropriate calibration equation. Two third proportion and one third of the whole data set were randomly selected for calibration and validation models respectively. The relation between the predicted and observed probabilities of cow pregnancy was approximately linear for calibration and validation models. The sensitivity-specificity combination for cow pregnancy increased when fatty acids were added to conventional milk characteristics as inputs to the different models (from 78 to 85% for sensitivity and from 40 to 52% for specificity). Results based on those models showed that it would be possible to help breeders to manage cow fertility using such tool implemented in the milk recording organizations. [less ▲]

Detailed reference viewed: 55 (21 ULg)
See detailWhen MIR spectrometry helps to promote a local and vulnerable breed
Colinet, Frédéric ULg; Dehareng, Frédéric; Dardenne, Pierre et al

in Book of Abstracts of the 62nd Annual Meeting of the European Association for Animal Production (2011, August)

The dual purpose Belgian Blue breed (DP-BB) is a vulnerable breed rooted in the tradition of the Walloon Region of Belgium. DP-BB has interesting features (e.g. robustness, good longevity and ease of ... [more ▼]

The dual purpose Belgian Blue breed (DP-BB) is a vulnerable breed rooted in the tradition of the Walloon Region of Belgium. DP-BB has interesting features (e.g. robustness, good longevity and ease of calving). Due to its dual purpose type, income generated by both milk and meat is more stable and more flexible in responding to market fluctuations. Registered DP-BB cows are milk recorded (one of the conditions for them to be registered as DP-BB and therefore to get AEM subsidies). Since near 4 years, during routine milk recording, nearly all mid-infrared (MIR) spectra generated at the milk labs and the information of test-day records were collected in a database. Calibration equations using the MIR spectrometry were developed permitting the prediction of several bovine milk components (e.g., fatty acids (FA)). Their application on the MIR spectral database would allow comparing milk composition from 920 DP-BB and 52,497 Holstein cows (selected cows had a proportion of Holstein or DP-BB in their breed composition of at least 90%). On average, each cows had 6 test-day records with MIR spectra in the database. MIR predictions were analyzed using GLM procedure with 5 fixed effects (breed, herd, lactation number, month of test-day recording and lactation stage); values presented are lsmeans (± s.e.) of the breed. Although milk and fat yields were lower for DP-BB, their FA proportions in fat were different from Holstein. Indeed, there are 66.0% (0.2) and 67.6% (0.0) of saturated FA in fat of milk for DP-BB and Holstein, respectively. Furthermore, the DP-BB milk fat was richer in omega-9 (20.7% (0.2) vs. 19.6% (0.0) for DP-BB and Holstein, respectively). Use of MIR predictions may help stakeholders to promote milk and future dairy products from DP-BB. [less ▲]

Detailed reference viewed: 21 (6 ULg)
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See detailIs there value in maintaining small populations ? Example of the Dual-Purpose Belgian Blue breed.
Gengler, Nicolas ULg; Soyeurt, Hélène ULg; Bastin, Catherine ULg et al

Conference (2011, July 13)

Current status of thinking on genomic selection in dairy cattle is mostly major breed centric (e.g., Holstein) and only for traditional traits (e.g., milk yields). Once you depart from this, it becomes ... [more ▼]

Current status of thinking on genomic selection in dairy cattle is mostly major breed centric (e.g., Holstein) and only for traditional traits (e.g., milk yields). Once you depart from this, it becomes obvious that different, often related, issues appear (e.g., lack of large training populations, need for expensive recording of new phenotypes). Also, there is an urgent need to rethink issues that are important for sustainability of dairy production (e.g., added value foods, animal robustness). In this context, small populations (breeds/lines) could represent a potential source of extra information to justify their maintenance. As marker densities increase, efficient dissection of different selection histories of divergent breeds or lines, potentially identifying pockets of unexploited variability will increase. A current example from the Belgian (Walloon) perspective is the Dual Purpose (DP) line of the Belgian Blue Breed (BBB), with presently around 4500 breeding females, for historical reason of which only 1500 have good pedigrees, and which is present in Belgium and northern France. Recent research, done on this line, showed its tendency to produce less saturated milk fat and to have better fertility. Results indicated that it could stay competitive in specific markets, especially because of largely increased meat value. Currently, the myostatin mutation is largely used for breeding purposes. To assess the genetic diversity of the breed, recently, over 200 genotypes (SNP50K) for nearly all breeding bulls of the last 20 years became available. HD genotypes should be available in the near future, also allowing to access selection history of this breed as being in between the 2 extreme breeds: Beef BBB (with which it shares a recent history) and Holstein-Friesian (which is related through its geographic proximity over centuries). Finally, genomic selection for DP-BBB will need to consider a single step type approach without the need of reference population and potentially relying heavily on SNP3K of cows, also with the objective to recreate relationships between animals of interest. [less ▲]

Detailed reference viewed: 58 (31 ULg)