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Insights into the genetic variation of maternal behavior and suckling performance of continental beef cows
No full textBackground: In beef cattle, maternal care is critical for calf survival and growth. Our objective was to evaluate the major sources of additive genetic variation in maternal behavior and suckling performance in two genetically close beef breeds. [br/]
Methods: Maternal performance was assessed based on maternal behavior (MB), milk yield (MY) and udder swelling score (US) of 1236 Blonde d’Aquitaine cows and 1048 Limousin cows. MB was scored just after calving to describe the intensity of the dam’s protective behavior towards her calf. Most of the cows were genotyped using the low-density chip EuroG10K BeadChip, and imputed to the high-density 770K panel within breed. Genetic parameters for each trait were estimated for each breed under a multi-trait best linear unbiased prediction animal model. Genomic analysis was performed for each breed using the high-density genotypes and a Bayesian variable selection method. [br/]
Results: Heritabilities were low for MB (0.11–0.13), intermediate for MY (0.33–0.45) and high for US (0.47–0.64). Genetic correlations between the traits ranged from 0.31 to 0.58 and 0.72 to 0.99 for the Blonde d’Aquitaine and Limousin breeds, respectively. Two quantitative trait loci (QTL) were detected for MB in Blonde d’Aquitaine with NPY1R and ADRA2A as candidate causative genes. Thirty to 56 QTL were detected for MY and US in both breeds and 12 candidate genes were identified as having a role in the genetic variation of suckling performance. Since very few pleiotropic QTL were detected, there was little biological explanation for the moderate (0.57) to very high (0.99) genetic correlations estimated between MY and US in the Blonde d’Aquitaine and Limousin cows, respectively. In Blonde d’Aquitaine, the correlation was largely due to the pleiotropic QTL detected in the region upstream of the CG gene, while in Limousin, this region was only identified for US, thus attesting the difference in genetic architecture between the breeds. [br/]
Conclusions: Our findings question the assumption that two populations that have close genetic links share many QTL. Nevertheless, we identified four candidate genes that may explain a substantial amount of the genetic variation in suckling performance of these two breeds
Détection de QTL et sélection génomique des qualités maternelles des vaches allaitantes
No full textReproduction, calving and milking performance of beef cows are included in maternal performance which are of major economic importance for beef cattle breeding. Beef cattle selection schemes use the progeny station tool to measure these phenotypes for the selection of the best insemination bulls. This coupled with the rapid ease of access to beef cattle genomic information, creates new opportunities for a more efficient selection of maternal performance. In this study, near 2 000 females with individual maternal performance were genotyped with low density chip (7 660 SNP) in two beef breeds, Blonde d'Aquitaine and Limousine. The genotypes were imputed in high density (more than 700 000 SNP). QTL detection was performed within breed with a Bayesian approach to test the association of the imputed genotypes and the performance. Among the QTL regions identified, a total of 41 candidate genes were proposed for sexual precocity (6), calving (11), milk performance (21) and maternal behavior (3). Several genomic selection methods were compared for maternal performance traits in Blonde d'Aquitaine breed. Minor differences of accuracy were found between single-trait evaluation methods. The "Single Step Genomic BLUP" multi-trait combining records from station and farm gave the more accurate genetic values for sorting bulls. Several genomic values accuracy improvements were proposed. The conditions of use of these indexes and the evolution of the selection scheme of maternal traits and the related tools are discussed.Les performances de reproduction, vêlage et allaitement des vaches forment les qualités maternelles qui sont d'une importance économique majeure en élevage allaitant. Les programmes de sélection des bovins allaitants utilisent l'outil de station de contrôle sur descendance pour mesurer ces phénotypes et identifier les meilleurs reproducteurs mâles afin de les diffuser par insémination animale. Avec la plus grande accessibilité à l'information génomique des animaux, il existe de nouvelles opportunités pour une sélection plus efficace des qualités maternelles. Près de 2 000 femelles phénotypées pour les qualités maternelles, ont été génotypées en basse densité (7 660 SNP) dans chacune des races Blonde d'Aquitaine et Limousine. Les génotypes ont été imputés en haute densité (plus de 700 000 SNP). Des détections de QTL ont été conduites intra-race en testant par approche bayésienne l'associatio de ces génotypes imputés avec les performances. Parmi les régions QTL identifiées un total de 41 gènes candidats a été proposé pour la précocité sexuelle (6), le vêlage (11), l'allaitement (21) et l'instinct maternel (3). Plusieurs méthodes de sélection génomiques ont été comparées pour les caractères des qualités maternelles en race Blonde d'Aquitaine. Des différences mineures de précision ont été constatées entre les méthodes en évaluation unicaractère. Le « Single Step Genomic BLUP » multi-caractère combinant les données collectées en station et en ferme fournit les valeurs génétiques les plus précises pour le choix des reproducteurs. Plusieurs pistes d'amélioration de la précision des index génomiques ont été proposées. Les modalités d’utilisation de ces index et d’évolution des outils et programmes de sélection des qualités maternelles sont également discutée
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
QTL detection and genomic selection of maternal performance of suckling cows
No full textLes performances de reproduction, vêlage et allaitement des vaches forment les qualités maternelles qui sont d'une importance économique majeure en élevage allaitant. Les programmes de sélection des bovins allaitants utilisent l'outil de station de contrôle sur descendance pour mesurer ces phénotypes et identifier les meilleurs reproducteurs mâles afin de les diffuser par insémination animale. Avec la plus grande accessibilité à l'information génomique des animaux, il existe de nouvelles opportunités pour une sélection plus efficace des qualités maternelles. Près de 2 000 femelles phénotypées pour les qualités maternelles, ont été génotypées en basse densité (7 660 SNP) dans chacune des races Blonde d'Aquitaine et Limousine. Les génotypes ont été imputés en haute densité (plus de 700 000 SNP). Des détections de QTL ont été conduites intra-race en testant par approche bayésienne l'associatio de ces génotypes imputés avec les performances. Parmi les régions QTL identifiées un total de 41 gènes candidats a été proposé pour la précocité sexuelle (6), le vêlage (11), l'allaitement (21) et l'instinct maternel (3). Plusieurs méthodes de sélection génomiques ont été comparées pour les caractères des qualités maternelles en race Blonde d'Aquitaine. Des différences mineures de précision ont été constatées entre les méthodes en évaluation unicaractère. Le « Single Step Genomic BLUP » multi-caractère combinant les données collectées en station et en ferme fournit les valeurs génétiques les plus précises pour le choix des reproducteurs. Plusieurs pistes d'amélioration de la précision des index génomiques ont été proposées. Les modalités d’utilisation de ces index et d’évolution des outils et programmes de sélection des qualités maternelles sont également discutéesReproduction, calving and milking performance of beef cows are included in maternal performance which are of major economic importance for beef cattle breeding. Beef cattle selection schemes use the progeny station tool to measure these phenotypes for the selection of the best insemination bulls. This coupled with the rapid ease of access to beef cattle genomic information, creates new opportunities for a more efficient selection of maternal performance. In this study, near 2 000 females with individual maternal performance were genotyped with low density chip (7 660 SNP) in two beef breeds, Blonde d'Aquitaine and Limousine. The genotypes were imputed in high density (more than 700 000 SNP). QTL detection was performed within breed with a Bayesian approach to test the association of the imputed genotypes and the performance. Among the QTL regions identified, a total of 41 candidate genes were proposed for sexual precocity (6), calving (11), milk performance (21) and maternal behavior (3). Several genomic selection methods were compared for maternal performance traits in Blonde d'Aquitaine breed. Minor differences of accuracy were found between single-trait evaluation methods. The "Single Step Genomic BLUP" multi-trait combining records from station and farm gave the more accurate genetic values for sorting bulls. Several genomic values accuracy improvements were proposed. The conditions of use of these indexes and the evolution of the selection scheme of maternal traits and the related tools are discussed
Détection de QTL et sélection génomique des qualités maternelles des vaches allaitantes
No full textReproduction, calving and milking performance of beef cows are included in maternal performance which are of major economic importance for beef cattle breeding. Beef cattle selection schemes use the progeny station tool to measure these phenotypes for the selection of the best insemination bulls. This coupled with the rapid ease of access to beef cattle genomic information, creates new opportunities for a more efficient selection of maternal performance. In this study, near 2 000 females with individual maternal performance were genotyped with low density chip (7 660 SNP) in two beef breeds, Blonde d'Aquitaine and Limousine. The genotypes were imputed in high density (more than 700 000 SNP). QTL detection was performed within breed with a Bayesian approach to test the association of the imputed genotypes and the performance. Among the QTL regions identified, a total of 41 candidate genes were proposed for sexual precocity (6), calving (11), milk performance (21) and maternal behavior (3). Several genomic selection methods were compared for maternal performance traits in Blonde d'Aquitaine breed. Minor differences of accuracy were found between single-trait evaluation methods. The "Single Step Genomic BLUP" multi-trait combining records from station and farm gave the more accurate genetic values for sorting bulls. Several genomic values accuracy improvements were proposed. The conditions of use of these indexes and the evolution of the selection scheme of maternal traits and the related tools are discussed.Les performances de reproduction, vêlage et allaitement des vaches forment les qualités maternelles qui sont d'une importance économique majeure en élevage allaitant. Les programmes de sélection des bovins allaitants utilisent l'outil de station de contrôle sur descendance pour mesurer ces phénotypes et identifier les meilleurs reproducteurs mâles afin de les diffuser par insémination animale. Avec la plus grande accessibilité à l'information génomique des animaux, il existe de nouvelles opportunités pour une sélection plus efficace des qualités maternelles. Près de 2 000 femelles phénotypées pour les qualités maternelles, ont été génotypées en basse densité (7 660 SNP) dans chacune des races Blonde d'Aquitaine et Limousine. Les génotypes ont été imputés en haute densité (plus de 700 000 SNP). Des détections de QTL ont été conduites intra-race en testant par approche bayésienne l'associatio de ces génotypes imputés avec les performances. Parmi les régions QTL identifiées un total de 41 gènes candidats a été proposé pour la précocité sexuelle (6), le vêlage (11), l'allaitement (21) et l'instinct maternel (3). Plusieurs méthodes de sélection génomiques ont été comparées pour les caractères des qualités maternelles en race Blonde d'Aquitaine. Des différences mineures de précision ont été constatées entre les méthodes en évaluation unicaractère. Le « Single Step Genomic BLUP » multi-caractère combinant les données collectées en station et en ferme fournit les valeurs génétiques les plus précises pour le choix des reproducteurs. Plusieurs pistes d'amélioration de la précision des index génomiques ont été proposées. Les modalités d’utilisation de ces index et d’évolution des outils et programmes de sélection des qualités maternelles sont également discutée
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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