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See detailInvited paper (Collège de France) Gravitational lensing and anomalous redshifts
Surdej, Jean ULiege; Claeskens, Jean-François ULiege; Sluse, Dominique ULiege

in Pecker, Jean-Claude; Narlikar, Jayant (Eds.) Current Issues in Cosmology (2006)

In this chapter, we should like to address the following question: can we invoke gravitational lensing as a possible explanation for anomalous redshifts? In the rest of the chapter, anomalous redshifts ... [more ▼]

In this chapter, we should like to address the following question: can we invoke gravitational lensing as a possible explanation for anomalous redshifts? In the rest of the chapter, anomalous redshifts refer to redshifts observed for two distinct objects with an angular separation less than 5" and whose difference is larger than 0.1. [less ▲]

Detailed reference viewed: 44 (18 ULiège)
See detailInvited Review Talk - Anomalous Transport Driven by Drift-Wave Turbulence
Thoul, Anne ULiege

Conference (1994, October)

Detailed reference viewed: 3 (0 ULiège)
See detailInvited Review Talk - Microscopic diffusion in stellar plasmas
Thoul, Anne ULiege

Conference (2006, November)

Detailed reference viewed: 9 (0 ULiège)
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Peer Reviewed
See detailInvited review: Large-scale indirect measurements for enteric methane emissions in dairy cattle: A review of proxies and their potential for use in management and breeding decisions
Negussie, E.; Haas, Y. De; Dehareng, F. et al

in Journal of Dairy Science (2017), 100(4), 2433-2453

Efforts to reduce the carbon footprint of milk production through selection and management of low-emitting cows require accurate and large-scale measurements of methane (CH4) emissions from individual ... [more ▼]

Efforts to reduce the carbon footprint of milk production through selection and management of low-emitting cows require accurate and large-scale measurements of methane (CH4) emissions from individual cows. Several techniques have been developed to measure CH4 in a research setting but most are not suitable for large-scale recording on farm. Several groups have explored proxies (i.e., indicators or indirect traits) for CH4; ideally these should be accurate, inexpensive, and amenable to being recorded individually on a large scale. This review (1) systematically describes the biological basis of current potential CH4 proxies for dairy cattle; (2) assesses the accuracy and predictive power of single proxies and determines the added value of combining proxies; (3) provides a critical evaluation of the relative merit of the main proxies in terms of their simplicity, cost, accuracy, invasiveness, and throughput; and (4) discusses their suitability as selection traits. The proxies range from simple and low-cost measurements such as body weight and high-throughput milk mid-infrared spectroscopy (MIR) to more challenging measures such as rumen morphology, rumen metabolites, or microbiome profiling. Proxies based on rumen samples are generally poor to moderately accurate predictors of CH4, and are costly and difficult to measure routinely on-farm. Proxies related to body weight or milk yield and composition, on the other hand, are relatively simple, inexpensive, and high throughput, and are easier to implement in practice. In particular, milk MIR, along with covariates such as lactation stage, are a promising option for prediction of CH4 emission in dairy cows. No single proxy was found to accurately predict CH4, and combinations of 2 or more proxies are likely to be a better solution. Combining proxies can increase the accuracy of predictions by 15 to 35%, mainly because different proxies describe independent sources of variation in CH4 and one proxy can correct for shortcomings in the other(s). The most important applications of CH4 proxies are in dairy cattle management and breeding for lower environmental impact. When breeding for traits of lower environmental impact, single or multiple proxies can be used as indirect criteria for the breeding objective, but care should be taken to avoid unfavorable correlated responses. Finally, although combinations of proxies appear to provide the most accurate estimates of CH4, the greatest limitation today is the lack of robustness in their general applicability. Future efforts should therefore be directed toward developing combinations of proxies that are robust and applicable across diverse production systems and environments. [less ▲]

Detailed reference viewed: 11 (4 ULiège)
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Peer Reviewed
See detailInvited review: Large-scale indirect measurements for enteric methane emissions in dairy cattle: A review of proxies and their potential for use in management and breeding decisions
Negussie, Enyew; de Haas, Yvette; Dehareng, Frédéric et al

in Journal of Dairy Science (2007), 100(4), 2433-2453

Detailed reference viewed: 27 (4 ULiège)
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See detailInvited review: Opportunities for genetic improvement of metabolic diseases
Pryce, J. E.; Gaddis Parker, K. L.; Koeck, A. et al

in Journal of Dairy Science (2016), 99(9), 6855-6873

Metabolic disorders are disturbances to one or more of the metabolic processes in dairy cattle. Dysfunction of any of these processes is associated with the manifestation of metabolic diseases or ... [more ▼]

Metabolic disorders are disturbances to one or more of the metabolic processes in dairy cattle. Dysfunction of any of these processes is associated with the manifestation of metabolic diseases or disorders. In this review, data recording, incidences, genetic parameters, predictors, and status of genetic evaluations were examined for (1) ketosis, (2) displaced abomasum, (3) milk fever, and (4) tetany, as these are the most prevalent metabolic diseases where published genetic parameters are available. The reported incidences of clinical cases of metabolic disorders are generally low (less than 10% of cows are recorded as having a metabolic disease per herd per year or parity/lactation). Heritability estimates are also low and are typically less than 5%. Genetic correlations between metabolic traits are mainly positive, indicating that selection to improve one of these diseases is likely to have a positive effect on the others. Furthermore, there may also be opportunities to select for general disease resistance in terms of metabolic stability. Although there is inconsistency in published genetic correlation estimates between milk yield and metabolic traits, selection for milk yield may be expected to lead to a deterioration in metabolic disorders. Under-recording and difficulty in diagnosing subclinical cases are among the reasons why interest is growing in using easily measurable predictors of metabolic diseases, either recorded on-farm by using sensors and milk tests or off-farm using data collected from routine milk recording. Some countries have already initiated genetic evaluations of metabolic disease traits and currently most of these use clinical observations of disease. However, there are opportunities to use clinical diseases in addition to predictor traits and genomic information to strengthen genetic evaluations for metabolic health in the future. [less ▲]

Detailed reference viewed: 4 (0 ULiège)
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See detailInvited review: overview of new traits and phenotyping strategies in dairy cattle with a focus on functional traits
Egger-Danner, C.; Cole, J. B.; Pryce, J. E. et al

in Animal (2015), 9(2), 191-207

For several decades, breeding goals in dairy cattle focussed on increased milk production. However, many functional traits have negative genetic correlations with milk yield, and reductions in genetic ... [more ▼]

For several decades, breeding goals in dairy cattle focussed on increased milk production. However, many functional traits have negative genetic correlations with milk yield, and reductions in genetic merit for health and fitness have been observed. Herd management has been challenged to compensate for these effects and to balance fertility, udder health and metabolic diseases against increased production to maximize profit without compromising welfare. Functional traits, such as direct information on cow health, have also become more important because of growing concern about animal well-being and consumer demands for healthy and natural products. There are major concerns about the impact of drugs used in veterinary medicine on the spread of antibiotic-resistant strains of bacteria that can negatively impact human health. Sustainability and efficiency are also increasingly important because of the growing competition for high-quality, plant-based sources of energy and protein. Disruptions to global environments because of climate change may encourage yet more emphasis on these traits. To be successful, it is vital that there be a balance between the effort required for data recording and subsequent benefits. The motivation of farmers and other stakeholders involved in documentation and recording is essential to ensure good data quality. To keep labour costs reasonable, existing data sources should be used as much as possible. Examples include the use of milk composition data to provide additional information about the metabolic status or energy balance of the animals. Recent advances in the use of mid-infrared spectroscopy to measure milk have shown considerable promise, and may provide cost-effective alternative phenotypes for difficult or expensive-to-measure traits, such as feed efficiency. There are other valuable data sources in countries that have compulsory documentation of veterinary treatments and drug use. Additional sources of data outside of the farm include, for example, slaughter houses (meat composition and quality) and veterinary labs (specific pathogens, viral loads). At the farm level, many data are available from automated and semi-automated milking and management systems. Electronic devices measuring physiological status or activity parameters can be used to predict events such as oestrus, and also behavioural traits. Challenges concerning the predictive biology of indicator traits or standardization need to be solved. To develop effective selection programmes for new traits, the development of large databases is necessary so that high-reliability breeding values can be estimated. For expensive-to-record traits, extensive phenotyping in combination with genotyping of females is a possibility. [less ▲]

Detailed reference viewed: 32 (6 ULiège)
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See detailInvited review: Phenotypes to genetically reduce greenhouse gas emissions in dairying
de Haas, Yvette; Pszczola, Marcin; Soyeurt, Hélène ULiege et al

in Journal of Dairy Science (2017), 100(2), 855-870

Detailed reference viewed: 26 (1 ULiège)
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See detailInvited talk "Observing gravitational lenses"
Surdej, Jean ULiege

Conference (1993)

Detailed reference viewed: 11 (1 ULiège)
See detailInvited talk - Anomalous Perturbative Transport by Drift-Wave Turbulence
Thoul, Anne ULiege

Scientific conference (1992, April)

Detailed reference viewed: 7 (0 ULiège)
See detailInvited talk - Accretion from AGB winds
Thoul, Anne ULiege

Conference (1999, September)

Detailed reference viewed: 6 (0 ULiège)
See detailInvited Talk - Anomalous Perturbative Transport in Tokamaks by Drift-Waves
Thoul, Anne ULiege

Conference (1993, February)

Detailed reference viewed: 4 (0 ULiège)
See detailInvited talk - The EASE scenario - Linking Halo Field Stars to Globular Clusters
Thoul, Anne ULiege

Scientific conference (1999, July)

Detailed reference viewed: 6 (0 ULiège)
See detailInvited talk - What determines the mass of galaxies?
Thoul, Anne ULiege

Scientific conference (1996, July)

Detailed reference viewed: 5 (0 ULiège)
See detailInvited talk - What determines the mass of galaxies?
Thoul, Anne ULiege

Scientific conference (1996, February)

Detailed reference viewed: 6 (0 ULiège)
See detailInvited talk - What determines the mass of galaxies?
Thoul, Anne ULiege

Scientific conference (1995, November)

Detailed reference viewed: 3 (0 ULiège)