References of "Gengler, Nicolas"
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See detailUsing milk spectral data for large-scale phenotypes linked to mitigation and efficiency
Soyeurt, Hélène ULiege; Vanlierde, Amélie ULiege; Vanrobays, Marie-Laure ULiege et al

in Book of abstracts of the 65th annual meeting of the European Federation of Animal Science (2014, August)

Even if producing milk efficiently has always been a major concern for producers, the direct environmental impact of their cows is becoming a novel one. Traits linked to this issue were identified as ... [more ▼]

Even if producing milk efficiently has always been a major concern for producers, the direct environmental impact of their cows is becoming a novel one. Traits linked to this issue were identified as methane emission (CH4), dry matter intake (DMI) and feed efficiency (FE); however they are available on a small scale. Researches showed that CH4 could be predicted from milk mid-infrared (MIR) spectra, allowing large-scale recording at low cost. The main objective of this study was to show, using a modelling approach, that DMI and FE could be derived from milk MIR spectra. For that, knowledge of body weight (BW) is required; however it was unknown in this study. Derived procedure was based on milk yield and composition, MIR CH4, and modelled standard animal requirements, allowing the prediction of expected BW. An external validation was conducted based on 91 actual records. 95% confidence limit for the difference ranged between -0.66 and 18.84 kg for BW, from -0.02 to 0.26 kg/day for DMI, and from -0.02 to 0.002 kg of fat corrected milk/kg DM for FE. Root mean square errors were 39.66 kg, 0.56 kg/d, and 0.03 kg/DM for the 3 studied traits. P-value for the t-test was not significant for BW and DMI. This suggests the possibility to obtain expected BW and therefore DMI from MIR spectra. Single trait animal test-day models used 1,291,850 records to assess the variability of studied traits. Significant variations were observed for the lactation stage, parity, genetics, and age. These findings were in agreement with the literature except for early lactation. This suggests in conclusion that the MIR information gave similar results for DMI and CH4 for the major part of lactation. The use of this novel method to predict expected BW offers new possibilities interesting for the development of genomic and genetic tools. [less ▲]

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See detailGenotype x Climate interactions for protein yield using four European Holstein Populations
Hammami, Hedi ULiege; Carabaño, Maria-Jesus; Logar, Betka et al

in Proceedings of 10th World Congress of Genetics Applied to Livestock Production (2014, August)

Reaction norm models were applied to investigate genetic variation in heat tolerance of Holsteins across environments using long term protein milk yield test-day records and weather variables as proxy of ... [more ▼]

Reaction norm models were applied to investigate genetic variation in heat tolerance of Holsteins across environments using long term protein milk yield test-day records and weather variables as proxy of climate change. Data represented four European regions characterized by different management systems and environments. Daily protein yield changed across the trajectory of temperature humidity index (THI) for all studied populations, pointing out negative associations between warm conditions and cow performance. For most regions, additive genetic variances for daily protein yield decrease when THI increases. Antagonistic relationships between level and intercept were relatively limited for Slovenia compared to the three other regions. Rank correlations of estimated breeding values for three proposed heat tolerance measures ranged from 0.56 (Spain and Slovenia) to 0.81 (Walloon Region of Belgium and Luxembourg), indicating a possibility of genotype by environment (G x E) for some pairs of regions. [less ▲]

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See detailCreation of universal MIR calibration by standardization of milk spectra: example of fatty acids
Grelet, Clément ULiege; Fernandez Pierna, Juan; Soyeurt, Hélène ULiege et al

in Book of abstracts of the 65th annual meeting of the European Federation of Animal Science (2014, August)

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See detailPrediction of Body Weight of Primiparous Dairy Cows Throughout Lactation
Vanrobays, Marie-Laure ULiege; Vandenplas, Jérémie ULiege; Hammami, Hedi ULiege et al

in Proceedings of the 10th World Congress on Genetics Applied to Livestock Production (2014, August)

Body weight (BW) can be computed using linear conformation traits (CBW). However, these traits are recorded mostly once during a lactation. Therefore, predicted BW (PBW) is needed throughout the lactation ... [more ▼]

Body weight (BW) can be computed using linear conformation traits (CBW). However, these traits are recorded mostly once during a lactation. Therefore, predicted BW (PBW) is needed throughout the lactation (e.g., allowing feed intake prediction in milk recording systems). A two-step procedure was developed to obtain PBW using a random regression test-day model using CBW as observations. Added second step consisted in changing prior distribution for additive genetic random effects using results from first step to predict again PBW. This method was applied on 24,919 primiparous Holstein cows having 25,061 CBW to obtain PBW for 232,436 test-days. Results showed that applying both steps provided more accurate estimates than using only the first step. Furthermore, this procedure predicting PBW throughout lactation is also extremely flexible because actual BW can also be used together with CBW, the prediction model being able to accommodate different levels of accuracies. [less ▲]

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See detailGenetic parameters for individual birth weight, weaning weight and final weight of crossbred pigs from Piétrain boars
Dufrasne, Marie ULiege; Wavreille, José; Piedboeuf, Maureen et al

Poster (2014, August)

Genetic parameters for birth weight (BWT), weaning weight (WWT), and final weight (BW) were estimated for crossbred pigs from Piétrain boars raised in test station. Estimates of direct heritability were ... [more ▼]

Genetic parameters for birth weight (BWT), weaning weight (WWT), and final weight (BW) were estimated for crossbred pigs from Piétrain boars raised in test station. Estimates of direct heritability were moderate (0.25 to 0.42), suggesting that genetic improvement of growth would be possible. Estimates of maternal heritability were 0.24 for BWT and WWT, and 0.05 for BW, indicating that the genetic influence of the dam on growth was not negligible until weaning. Genetic correlations between direct and maternal effects for BWT and WWT were moderate and unfavorable (-0.52 and -0.57 respectively). Direct genetic correlations were high and favorable between traits (0.40 to 0.75), suggesting that a high BWT is a good predictor to produce pigs with high final weight. Maternal genetic correlations between traits were low (0.01 to 0.03). Selection for higher BWT would increase final market weight but should be balanced with survival traits. [less ▲]

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See detailQuel système d'évaluations génétiques pour les verrats Piétrain en Wallonie
Dufrasne, Marie ULiege; Piedboeuf, Maureen; Wavreille, José et al

Article for general public (2014)

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See detailNon-genetic sources of variation of milk production and reproduction and interactions between both classes of traits in Sicilo-Sarde dairy sheep.
Merai, A.; Gengler, Nicolas ULiege; Hammami, Hedi ULiege et al

in Animal (2014), 8(9), 1534-9

This work aimed to study the sources of variation in productive and reproductive traits of the dairy Sicilo-Sarde ewes and to further investigate the interaction between both classes of traits. After ... [more ▼]

This work aimed to study the sources of variation in productive and reproductive traits of the dairy Sicilo-Sarde ewes and to further investigate the interaction between both classes of traits. After edits, a database containing 5935 lactation records collected during 6 successive years in eight dairy flocks in the North of Tunisia was used. Total milked milk (TMM) in the milking-only period was retained as productive trait. The interval from the start of the mating period to the subsequent lambing (IML) and the lambing status (LS) were designed as reproductive traits. Sicilo-Sarde ewes had an average TMM of 60.93 l (+/-44.12) during 132.8 days (+/-46.6) after a suckling period of 100.4 days (+/-24.9). Average IML was 165.7 days. In a first step, the major factors influencing milk production and reproductive traits were determined. The significant sources of variation identified for TMM were: flock, month of lambing, year of lambing, parity, suckling length, litter size and milking-only length. Flockxmonth of the start of the mating period, parity, year of mating and litter size were identified as significant factors of variation for IML, while flockxmonth of the start of the mating period, parity and year of mating were identified as significant sources of variation for LS. In a second step, variance components were estimated using a three traits threshold mixed model, which combined LS as categorical trait and TMM and IML as continuous traits. Repeatability estimates were 0.21 (+/-0.03) for TMM, 0.09 (+/-0.02) for IML, and 0.10 (+/-0.05) for LS. Moreover, TMM and IML were found to be favorably associated for the flockx year of lambing effect (-0.45+/-0.18) but unfavorably associated for the animal effect (0.20+/-0.09). [less ▲]

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See detailThe road to genetic selection for methane emission from ruminants: A global approach
de Haas, Y.; Lassen, J.; Pickering, N.K. et al

Conference (2014, May 22)

Measuring and mitigating methane (CH4) emissions from livestock is of increasing political and economic importance. Potentially, the most sustainable way of reducing CH4 emission from ruminants is through ... [more ▼]

Measuring and mitigating methane (CH4) emissions from livestock is of increasing political and economic importance. Potentially, the most sustainable way of reducing CH4 emission from ruminants is through the estimation of genomic breeding values to facilitate genetic selection. Enteric CH4 emissions are difficult and expensive to measure, thus genomic prediction could provide significant, long term economic benefits. Implementation will require global collaboration to define a suitable measure and many thousands of records to ensure valid and accurate evaluations. A number of approaches for individual measures on a large scale have been recently proposed including fixed and portable respiratory chambers, SF6 tracer gas, laser detector systems and sniffers or spot samples at milking. Some studies have also shown promising results in predicting individual animal CH4 emission from mid infra-red milk spectra data. It is currently unclear, however, how well measures between these approaches correlate. Comparison and validation of these novel phenotypes presents a huge task over the coming years. A crucial first step is to define a trait phenotype and measuring protocols to create a robust resource for the global sharing and comparison of data, and further, to measure correlations with production traits. Proposed phenotypes could be measures of “total methane emissions”, measured in grams CH4 per day, or “methane yield” measured in grams CH4 per kg dry matter intake (DMI) when DMI is available as a phenotype, or “methane intensity” measured in grams CH4 per kg of produced human edible protein. Here, we describe how two recently established entities; an ICAR Working Group and the EU COST-Action network METHAGENE are working in close collaboration to successfully address these major challenges together with the Animal Selection Genetics and Genomics Network (ASGGN) of the Livestock Research Group of the Global Research Alliance (GRA) on agricultural greenhouse gases. [less ▲]

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See detailHarmonization of recording and use of direct health data as basis of sustainable improvement of dairy health and longevity
Stock, K.F.; Cole, J.B.; Pryce, J.E. et al

Conference (2014, May 22)

Animal health and welfare issues have emerged as important factors for efficiency, competitiveness and public acceptance of livestock keeping and breeding worldwide. In dairy cattle, health monitoring has ... [more ▼]

Animal health and welfare issues have emerged as important factors for efficiency, competitiveness and public acceptance of livestock keeping and breeding worldwide. In dairy cattle, health monitoring has been in the focus of multiple research projects since the 1970s. Information on diseases from veterinary records and on-farm documentation systems are the main sources of direct health data, for which routine genetic evaluations were first implemented in the Nordic countries and more recently in a few other countries. The goal of the ICAR Functional Traits Working Group is to deliver information and tools that facilitate the use of health data across sectors and countries, thereby supporting the implementation of sustainable health monitoring and improvement systems. The ICAR guidelines for Recording, Evaluation and Genetic Improvement of Health Traits cover different approaches for the collection and use of health data in dairy management and breeding, and recommend best practices. Standardization is essential for building up the required information base on dairy health by collaborative and integrative approaches, and the hierarchically structured, comprehensive key for health data recording can serve as a reference which facilitates the connection of data sources. International and terdisciplinary exchange of experiences and collaborations can contribute to the development of efficient breeding strategies with increased weight on health and welfare traits. The ICAR 2013 Health Data Conference showed the potential of broad adoption of the available health data standards for the benefit of all stakeholders in the dairy sector. Clear and restrictive regulations regarding access and use of health information help increase the rate of data integration which is needed for maximum performance regarding support of short- and long-term improvements of the dairy herd. Based on internationally harmonized recording of direct health data, joining of sectoral, regional and national initiatives is expected to propel the targeted improvement of health, welfare, and longevity in dairy breeding. [less ▲]

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See detailContributions à l’amélioration des systèmes d’évaluations génétiques
Vanderick, Sylvie ULiege; Gengler, Nicolas ULiege

Conference given outside the academic context (2014)

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See detailThe uses of mid-infrared spectral information from milk recording organization to certify milk geographic origin
Dale, Laura Monica; Laine, Aurélie ULiege; Bastin, Catherine et al

in Book of Short Abstracts - 19th National Symposium on Applied Biological Sciences (2014, February 07)

This study investigated the opportunity to detect the geographic origin of milk from the midinfrared (MIR) analysis of milk. Milk MIR spectral data related to milk recording data were available in the ... [more ▼]

This study investigated the opportunity to detect the geographic origin of milk from the midinfrared (MIR) analysis of milk. Milk MIR spectral data related to milk recording data were available in the Belgium Walloon Region via European project OptiMIR (INTERREG IVB North West Europe Program). In Wallonia, the Ardenne region is associated to a traditional product of the area, a appellation d'origine “Beurre d’Ardennes”. Therefore, discrimination studies were conducted to distinguish Ardennes region from the rest of Wallonia. A total of 542,733 Walloon spectral records linked to their geographic origin were used (97,369 of MIR spectra for Ardennes region and 450,326 for the rest of Wallonia). The spectral data selected and pre-treated were adjusted for the effects of breeds, months, years and days in milk using ab appropriate mixed model. To test the MIR ability for milk authentication, chemometric tools, such as quadratic discriminant analysis were applied to the adjusted spectrafor three MIR spectral regions (e.g. 930-1600 cm-1, 1710-1810 per cm and 2560-2990 per cm). Results of classification showed that 94% of the records from the Ardernnes region were properly classified. Based on this results, MIR spectroscopy techniques may provide useful fingerprints to detect geographic origin and could be potentially used in routine management decision and quality assurance tools. [less ▲]

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See detailEstimating daily yield and content of major fatty acids from single milking
Arnould, Valérie ULiege; Reding, Romain; Delvaux, Charles et al

Poster (2014, February 07)

Reducing the frequency of milk recording and the number of recorded samples per test-day could be a solution in order to reduce costs of official milk recording. However, fewer samples lead to a decrease ... [more ▼]

Reducing the frequency of milk recording and the number of recorded samples per test-day could be a solution in order to reduce costs of official milk recording. However, fewer samples lead to a decrease in the accuracy of predicted daily yields. Unfortunately, the current published equations use the milking interval that is often not available and/or reliable in practice. The first objective of this study was to propose models using easily available traits. Therefore the milking interval was replaced by a combination of data easily recorded by milk recording. The second objective of this study was to enlarge the previous investigations to milk fatty acids (FA) in order to propose a practical method for estimating accurate daily milk, fat and major FA yields from single milking. The fit goodness of proposed models was evaluated based on the correlation values between the estimated and observed daily yields in addition to the calculation of the mean square error. Obtained results are promising. Correlation values were comprised between 96.4% and 97.6% when daily yield were estimated from morning milking, and from 96.9% to 98.3% when daily yield were estimated from evening milking. The combination of records related to lactation stage, month of test, milk yield, and fat could replace the milking interval effect. Because of their simplicity, proposed models would be easy to implement. [less ▲]

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See detailConsequences of Selection for Environmental Impact Trait in Dairy Cows
Kandel, Purna Bhadra ULiege; Vanderick, Sylvie ULiege; Vanrobays, Marie-Laure ULiege et al

Scientific conference (2014, February 07)

Environmental sustainability is gaining importance in dairy industry due to enteric methane (CH4) emission from dairy cows. We predicted CH4 indicator trait (CH4 intensity: CH4 g/kg of milk) from Mid ... [more ▼]

Environmental sustainability is gaining importance in dairy industry due to enteric methane (CH4) emission from dairy cows. We predicted CH4 indicator trait (CH4 intensity: CH4 g/kg of milk) from Mid-infrared spectra of milk samples and recorded milk yield. Genetic correlations between CH4 intensity and milk production traits were estimated on Holstein cows from correlations of estimated breeding values. Genetic correlations between CH4 intensity and milk yield (MY) was -0.67, fat yield (FY) -0.13, protein yield (PY) -0.46, somatic cell score (SCS) 0.02, longevity -0.07, fertility 0.31, body condition score (BCS) 0.27 and average of confirmation traits -0.23. Currently, there is no CH4 emission trait in genetic evaluation selection index. Putting an hypothetical 25% weight on CH4 intensity on current Walloon genetic evaluation selection index and proportional reduction on other selection traits, the response to selection will be reduction of CH4 emission intensity by 24%, increase in MY by 30%, FY by 17%, PY by 29%, SCS by -15%, longevity by 24%, fertility by -11%, BCS by -13% and conformation traits by 24%. In conclusion, introduction of environmental traits in current selection index will affect selection responses. As there is no economic value of these traits presently alternative methods like putting correlated traits with clear economic value (e.g. feed efficiency) in the selection objective could generate appropriate index weights. [less ▲]

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See detailEfficient computation of genomically-enhanced inbreeding coefficients
Faux, Pierre ULiege; Gengler, Nicolas ULiege

Poster (2014, February 07)

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See detailSystème d’évaluation génétique des verrats Piétrain en croisement en Wallonie
Dufrasne, M.; Gengler, Nicolas ULiege

Speech/Talk (2014)

Pour que la production porcine soit la plus compétitive possible, elle doit être efficace. Les systèmes d’évaluations génétiques permettent de sélectionner les meilleurs animaux pour être les parents des ... [more ▼]

Pour que la production porcine soit la plus compétitive possible, elle doit être efficace. Les systèmes d’évaluations génétiques permettent de sélectionner les meilleurs animaux pour être les parents des générations futures. Ce document à pour objectif de présenter le système d’évaluations génétiques des verrats Piétrain en Wallonie. Le système est en développement et les différents modèles utilisés pourront encore être améliorés pour fournir des valeurs d’élevage qui soient les plus précises possibles et pour intégrer de nouveaux caractères. [less ▲]

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See detailEvaluation de la qualité externe et interne des œufs de cinq variétés de pintades locales élevées au bénin.
Houndonougbo, Pascal ULiege; Chrysostome, A.A. Christophe; Houndonougbo, M. Frédéric et al

in Revue du Conseil Africain et Malgache pour l'Enseignement Supérieur (2014), 2(2), 42-47

The study aimed to evaluate the external and internal qualities of eggs from local varieties of guinea fowl (Common breed, Bonaparte, White, Grey and Black) of Benin. Twenty –four (24) guinea fowl of ... [more ▼]

The study aimed to evaluate the external and internal qualities of eggs from local varieties of guinea fowl (Common breed, Bonaparte, White, Grey and Black) of Benin. Twenty –four (24) guinea fowl of guinea fowl of each variety aged of 38 weeks were reared in station and five new-laid eggs were collected daily and analyzed weekly by variety during 8 weeks. It appears that White guinea fowl lay the heaviest eggs while Bonaparte laid the smallest (P<0.05). According to the egg size, White guinea fowls were the best followed by Black guinea fowl, Common guinea fowl and Grey guinea fowl. Eggshell color was mostly red bright and dark red. The predominant bright red eggs were obtained in black guinea fowl (55%), Bonaparte (42.5%) and Common (40%), while the dark red were mostly recorded in White (45%) and Grey guinea fowls (42.5%). The slight red shell eggs with grits were only obtained in White variety (2.5%) and mottled eggs were produced by the Grey guinea fowl (25%) followed by Bonaparte guinea fowl (20%). Furthermore, egg from white guinea showed the best physical quality that are egg white thickness, egg yolk thickness, egg white weight and egg yolk weight (respectively 6.82 mm 17.8 mm; 13g and 22g). The most colored egg yolk was found in black guinea fowls while the less colored was observed in the common greed. In short, it appears from this study that qualities of eggs depend on genetic type and could be used for characterization and genetic improvement by selection and crossing. [less ▲]

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See detailA review of inversion techniques related to the use of relationship matrices in animal breeding
Faux, Pierre ULiege; Gengler, Nicolas ULiege

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(3), 319-468

In animal breeding, prediction of genetic effects is usually obtained through the use of mixed models. For any of these genetic effects, mixed models require the inversion of the covariance matrix ... [more ▼]

In animal breeding, prediction of genetic effects is usually obtained through the use of mixed models. For any of these genetic effects, mixed models require the inversion of the covariance matrix associated to that effect, which is equal to the associated relationship matrix times the associated component of the genetic variance. Given the size of many genetic evaluation systems, computing the inverses of these relationship matrices is not trivial. In this review, we aim to cover computational techniques that ease inversion of relationship matrices used in animal breeding for prediction of the following different types of genetic effects: additive effect, gametic effect, effect due to presence of marked quantitative trait loci, dominance effect and different epistasis effects. Construction rules and inversion algorithms are detailed for each relationship matrix. In the final discussion, we draw up a common theoretical frame to most of the reviewed techniques. Two computational constraints come out of this theoretical frame: setting up the matrix of dependencies between levels of the effect and setting up some parts (diagonal or block-diagonal elements) of the relationship matrix to be inverted. [less ▲]

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See detailStrategies to combine novel traits across countries: example of heat stress
Hammami, Hedi ULiege; Vandenplas, Jérémie ULiege; Carabaño, Maria-Jesus et al

in Interbull Bulletin (2014), 48

Nowadays, novel traits are of great interest. However, phenotypes are siloed and mainly not shared. Heat stress is becoming problematic affecting animals’ performances and their well-being. Heat stress ... [more ▼]

Nowadays, novel traits are of great interest. However, phenotypes are siloed and mainly not shared. Heat stress is becoming problematic affecting animals’ performances and their well-being. Heat stress tolerance as a novel trait is only addressed by isolated within-country research studies. Integration and combination of local and foreign information sources is needed for better accuracy genetic evaluations. Therefore, this study was aimed to test the potential combination of sources of external information towards the evaluation of heat stress tolerance of dairy cattle. Long-term cow performances linked to environmental descriptors (weather parameters as proxy to climate change) collected over 10 years under the temperate conditions of the Walloon Region of Belgium and the hotter and warm Mediterranean conditions of Andalusia and Castile-La-Mancha Spanish regions were available. A total of 1,604,775 milk, fat, and protein test-day (TD) records linked to average daily temperature humidity (THI) values for 3-day lag before each TD were considered. Under a first strategy considering free-access to raw-data (phenotype and pedigree), a joint evaluation was firstly run using reaction norm models where production traits were considered as function of THI. A Belgian and a Spanish evaluation were also run using the same model. An alternative strategy considering only access to external information (i.e. regression coefficients for additive genetic effects (â and their associated REL)) was tested. In this case, foreign â and their REL resulting from the Spanish evaluation were first converted to the Belgian trait and thereafter integrated in the Belgian <br /><br />evaluation using a Bayesian approach. Rank correlations between regression coefficients, â (of the 1,104 bulls having daughters only in Spain) estimated by Belgian evaluation and â estimated by the joint evaluation were moderate (<=0.70). Corresponding rank correlations between â estimated by joint and Bayesian evaluations were significantly higher (ranging from 0.967 to 0.998), indicating that the Bayesian evaluation integrating external information was in good concordance with the joint evaluation. Results from this study indicated that the integration of external information via the Bayesian approach has a good potential to improve the genetic evaluation of sparse and siloed novel traits. [less ▲]

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See detailUnified method to integrate and blend several, potentially related, sources of information for genetic evaluation
Vandenplas, Jérémie ULiege; Colinet, Frédéric ULiege; Gengler, Nicolas ULiege

in Genetics, Selection, Evolution (2014), 46

Background A condition to predict unbiased estimated breeding values by best linear unbiased prediction is to use simultaneously all available data. However, this condition is not often fully met. For ... [more ▼]

Background A condition to predict unbiased estimated breeding values by best linear unbiased prediction is to use simultaneously all available data. However, this condition is not often fully met. For example, in dairy cattle, internal (i.e. local) populations lead to evaluations based only on internal records while widely used foreign sires have been selected using internally unavailable external records. In such cases, internal genetic evaluations may be less accurate and biased. Because external records are unavailable, methods were developed to combine external information that summarizes these records, i.e. external estimated breeding values and associated reliabilities, with internal records to improve accuracy of internal genetic evaluations. Two issues of these methods concern double-counting of contributions due to relationships and due to records. These issues could be worse if external information came from several evaluations, at least partially based on the same records, and combined into a single internal evaluation. Based on a Bayesian approach, the aim of this research was to develop a unified method to integrate and blend simultaneously several sources of information into an internal genetic evaluation by avoiding double-counting of contributions due to relationships and due to records. Results This research resulted in equations that integrate and blend simultaneously several sources of information and avoid double-counting of contributions due to relationships and due to records. The performance of the developed equations was evaluated using simulated and real datasets. The results showed that the developed equations integrated and blended several sources of information well into a genetic evaluation. The developed equations also avoided double-counting of contributions due to relationships and due to records. Furthermore, because all available external sources of information were correctly propagated, relatives of external animals benefited from the integrated information and, therefore, more reliable estimated breeding values were obtained. Conclusions The proposed unified method integrated and blended several sources of information well into a genetic evaluation by avoiding double-counting of contributions due to relationships and due to records. The unified method can also be extended to other types of situations such as single-step genomic or multi-trait evaluations, combining information across different traits. [less ▲]

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