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Background Survival from birth to slaughter is an important economic trait in commercial pig productions. Increasing survival can improve both economic efficiency and animal welfare. The aim of this study is to explore the impact of genotyping strategies and statistical models on the accuracy of genomic prediction for survival in pigs during the total growing period from birth to slaughter. Results We simulated pig populations with different direct and maternal heritabilities and used a linear mixed model, a logit model, and a probit model to predict genomic breeding values of pig survival based on data of individual survival records with binary outcomes (0, 1). The results show that in the case of only alive animals having genotype data, unbiased genomic predictions can be achieved when using variances estimated from pedigree-based model. Models using genomic information achieved up to 59.2% higher accuracy of estimated breeding value compared to pedigree-based model, dependent on genotyping scenarios. The scenario of genotyping all individuals, both dead and alive individuals, obtained the highest accuracy. When an equal number of individuals (80%) were genotyped, random sample of individuals with genotypes achieved higher accuracy than only alive individuals with genotypes. The linear model, logit model and probit model achieved similar accuracy. Conclusions Our conclusion is that genomic prediction of pig survival is feasible in the situation that only alive pigs have genotypes, but genomic information of dead individuals can increase accuracy of genomic prediction by 2.06% to 6.04%.

Pig mortality is a big welfare and economic challenge. This study investigated the feasibility of reducing mortality of pigs from day 5 to slaughter and from birth to slaughter by breeding. Data of 163,782 female pigs were from DanBred Yorkshire breeding herds. Variances and breeding values were estimated using a linear, a logit and a probit model based on mortality record (0, 1) at individual level. Estimates of direct heritabilities ranged from 0.013 to 0.017 and maternalheritabilities from 0.005 to 0.017. Estimated breeding values (EBVs) from the three models were highly consistent. Although low heritabilities, validation accuracies of EBVs ranged from 0.415 to 0.420 for direct EBVs, from 0.192 to 0.392 for maternal EBVs, and from 0.357 to 396 for total EBVs. The results indicate that reducing pig mortality by breeding is feasible, and linear model is efficient for genetic evaluation of pig mortality.

This study compared four genotyping scenarios of genomic prediction for survival in a simulated pig population with survival rate of 80%. Breeding values were predicted using a linear mixed model and a logit model, based on individual records. The scenarios in order of prediction accuracy were: genotyping all individuals, randomly genotyping 80% individuals, genotyping alive individuals, and no genotyping. Using variance components estimated from pedigree-based model, genomic predictions with genotypes only from alive animals were unbiased. Given the same number of genotyped individuals, random genotyping 80% individuals led to higher prediction accuracy than only genotyping alive individuals, indicating the importance of genotype information of dead pigs. Moreover, the linear and the logit models achieved similar accuracy. We concludethat genotyping dead individuals should be considered, and a linear model can be used for predicting breeding values of survival in pigs.

Records on groups of individuals could be valuable for predicting breeding values when a trait is difficult or costly to measure on single individuals, such as feed intake and egg production. Adding genomic information has shown improvement in the accuracy of genetic evaluation of quantitative traits with individual records. Here, we investigated the value of genomic information for traits with group records. Besides, we investigated the improvement in accuracy of genetic evaluation for group-recorded traits when including information on a correlated trait with individual records. The study was based on a simulated pig population, including three scenarios of group structure and size. The results showed that both the genomic information and a correlated trait increased the accuracy of estimated breeding values (EBVs) for traits with group records. The accuracies of EBV obtained from group records with a size 24 were much lower than those with a size 12. Random assignment of animals to pens led to lower accuracy due to the weaker relationship between individuals within each group. It suggests that group records are valuable for genetic evaluation of a trait that is difficult to record on individuals, and the accuracy of genetic evaluation can be considerably increased using genomic information. Moreover, the genetic evaluation for a trait with group records can be greatly improved using a bivariate model, including correlated traits that are recorded individually. For efficient use of group records in genetic evaluation, relatively small group size and close relationships between individuals within one group are recommended.

Grise er sociale dyr, som interagerer med de dyr, som de går sammen med. Derfindes grise, som gør noget godt for de andre grise, og der findes grise, som haren negativ indflydelse på andre grise. I arbejdet med at øge dyrevelfærden igriseproduktionen og forbedre produktiviteten har forskere fra danske SEGESSvineproduktion, Aarhus Universitet og SRUC (Scotland's Rural College)undersøgt, om de sociale egenskaber hos grise kan forbedres gennem avl.Resultaterne tyder på, at det faktisk er muligt. Forskningen er gennemført medstøtte fra GUDP (Grønt Udviklings- og Demonstrationsprogram) underLandbrugs- og Fiskeristyrelsen. Målet har været at udvikle en metode til atberegne en social avlsværdi til avlsgrise og dermed udvælge de grise med debedste sociale gener som forældre til fremtidens grise for avlsselskabetDanBred.

The transitions from foraging to farming and later to pastoralism in Stone Age Eurasia (c. 11-3 thousand years before present, BP) represent some of the most dramatic lifestyle changes in human evolution. We sequenced 317 genomes of primarily Mesolithic and Neolithic individuals from across Eurasia combined with radiocarbon dates, stable isotope data, and pollen records. Genome imputation and co-analysis with previously published shotgun sequencing data resulted in >1600 complete ancient genome sequences offering fine-grained resolution into the Stone Age populations. We observe that: 1) Hunter-gatherer groups were more genetically diverse than previously known, and deeply divergent between western and eastern Eurasia. 2) We identify hitherto genetically undescribed hunter-gatherers from the Middle Don region that contributed ancestry to the later Yamnaya steppe pastoralists; 3) The genetic impact of the Neolithic transition was highly distinct, east and west of a boundary zone extending from the Black Sea to the Baltic. Large-scale shifts in genetic ancestry occurred to the west of this “Great Divide”, including an almost complete replacement of hunter-gatherers in Denmark, while no substantial ancestry shifts took place during the same period to the east. This difference is also reflected in genetic relatedness within the populations, decreasing substantially in the west but not in the east where it remained high until c. 4,000 BP; 4) The second major genetic transformation around 5,000 BP happened at a much faster pace with Steppe-related ancestry reaching most parts of Europe within 1,000-years. Local Neolithic farmers admixed with incoming pastoralists in eastern, western, and southern Europe whereas Scandinavia experienced another near-complete population replacement. Similar dramatic turnover-patterns are evident in western Siberia; 5) Extensive regional differences in the ancestry components involved in these early events remain visible to this day, even within countries. Neolithic farmer ancestry is highest in southern and eastern England while Steppe-related ancestry is highest in the Celtic populations of Scotland, Wales, and Cornwall (this research has been conducted using the UK Biobank resource); 6) Shifts in diet, lifestyle and environment introduced new selection pressures involving at least 21 genomic regions. Most such variants were not universally selected across populations but were only advantageous in particular ancestral backgrounds. Contrary to previous claims, we find that selection on the FADS regions, associated with fatty acid metabolism, began before the Neolithisation of Europe. Similarly, the lactase persistence allele started increasing in frequency before the expansion of Steppe-related groups into Europe and has continued to increase up to the present. Along the genetic cline separating Mesolithic hunter-gatherers from Neolithic farmers, we find significant correlations with trait associations related to skin disorders, diet and lifestyle and mental health status, suggesting marked phenotypic differences between these groups with very different lifestyles. This work provides new insights into major transformations in recent human evolution, elucidating the complex interplay between selection and admixture that shaped patterns of genetic variation in modern populations.Competing Interest StatementThe authors have declared no competing interest.

Additional file 1: Figure S1. Scatter plot of Pearson’s correlations of (genomic) estimated breeding value ((G)EBV) based on full and reduced datasets ( $$\rho_{f,r}$$ ρ f , r ) versus the absolute difference in (G)EBV between the full and reduced datasets ( $$d_{f,r}$$ d f , r ) for all 323 groups for univariate PBLUP (panel A), bivariate PBLUP (panel B), univariate ssGBLUP (panel C), and bivariate ssGBLUP (panel D).

Changes in funerary practices are key to the understanding of social transformations of past societies. Over the course of the Nordic Bronze Age, funerary practices changed from inhumation to cremation. The aim of this study is to shed light on this fundamental change through a cross-examination of archaeometric provenance data and archaeological discussions of the context and layouts of early cremation graves. To this end, we conducted 19 new provenance analyses of strontium isotopes from Early Nordic Bronze age contexts in Thisted County and Zealand and Late Bronze Age contexts from Thisted County and Vesthimmerland (Denmark). These data are subsequently compared with data from other extant relevant studies, including those from Late Bronze Age Fraugde on the Danish island of Fyn.Overall, the variations within our provenience data suggest that the integration and establishment of cremation may not have had a one-to-one relationship with in-migration to Nordic Bronze Age Denmark. Moreover, there seems to be no single blanket scenario which dictated the uptake of cremation as a practice within this part of Southern Scandinavia. By addressing habitus in relation to the deposition of cremations as juxtaposed with these provenance data¸ we hypothesize several potential pathways for the uptake of cremation as a new cultural practice within the Danish Nordic Bronze Age and suggest that this may have been a highly individual process, whose tempo may have been dictated by the specificities of the region(s) concerned.

Om afsnittet Kirker og Bosætninger: I begyndelse af 1800-årene tog det Kongelige Nordiske Oldskriftselskab initiativet til systematiske registreringer og kortlægning af de mange ruiner i henholdsvis Sydvestgrønland og i området omkring Nuuk. Kirkebygningerne fik særlig opmærksomhed. De var letgenkendelige i landskabet, og forskningen var især rettet mod arkitekturen og kirkernes dateringer. De sidste skete ved sammenligninger med kirkearkitekturen på de Britiske Øer og i Skandinavien. Mange nye kirker er registreret siden Oldskrifselskabet udgav det monumentale tre-bind-værk Grønlands Historiske Mindesmærker (1838 – 1845). Med brugen af 14C dateringsmetoden er det i dag muligt at komme tættere på dateringerne af brugen af de enkelte kirker, og bygningerne kan nu også vurderes i et bredere socioøkonomisk perspektiv. Her vurderes bebyggelsesdynamikken i nordbobygderne med udgangspunkt i kirkebyggeriet.

Additional file 1. Investigation of predictive performance.

The aim of this study was to examine (i) the genetic variation in macro-environmental sensitivity (macro-ES) for ADG in Danish Duroc pigs, (ii) the genetic heterogeneity among sexes, and (iii) residual variance heterogeneity among herds. Record of ADG for 32,297 boars (19 herds) and 42,724 gilts (16 herds) was used for analysis. The data were provided by the National Danish Pig Research Centre. The analysis was performed by fitting univariate reaction norm models with the herd-year-month on test (HYM) effect as environmental covariates and herd-specific residual variance for boars and gilts separately under a Bayesian setting. The environmental covariate was inferred simultaneously with other parameters of the model. Gibbs sampling was used to sample model dispersion and location parameters. The posterior means and highest posterior density intervals of the additive genetic variance, genetic correlations for ADG, and heritability were calculated over the continuous environmental range of −3σh to +3σh (SD of the HYM effect). The coheritability of ADG at the average environmental level and ADG in the environments along the −3σh to +3σh environmental gradient were also calculated. The analysis showed significant variation in macro-ES, revealing genotype by environment interactions (G × E) for ADG. The presence of G × E resulted in changes in additive genetic variance and heritability across the −3σh to +3σh range. The genetic correlations were high and positive between ADG in environments differing by 1σh units or less and decreased to moderately positive between ADG in the extreme environments in both sexes. The coheritability of ADG in the environment at the average level and the −3σh environment for boars were greater than the heritability in the environment at the average level, while it was less for gilts. The coheritability of ADG in the environment at the average level and the +3σh environment for boars was less than heritability in the environment at the average level, while it was either the same or greater for gilts, depending on the residual variance. Boars had larger additive genetic and residual variances than gilts. Heterogeneity of residual variances across herds was shown for both sexes. In conclusion, this study shows the presence of macro-ES, genetic variance heterogeneity among sexes for ADG in pigs, and residual variance heterogeneity across herds. The aim of this study was to examine (i) the genetic variation in macro-environmental sensitivity (macro-ES) for ADG in Danish Duroc pigs, (ii) the genetic heterogeneity among sexes, and (iii) residual variance heterogeneity among herds. Record of ADG for 32,297 boars (19 herds) and 42,724 gilts (16 herds) was used for analysis. The data were provided by the National Danish Pig Research Centre. The analysis was performed by fitting univariate reaction norm models with the herd-year-month on test (HYM) effect as environmental covariates and herd-specific residual variance for boars and gilts separately under a Bayesian setting. The environmental covariate was inferred simultaneously with other parameters of the model. Gibbs sampling was used to sample model dispersion and location parameters. The posterior means and highest posterior density intervals of the additive genetic variance, genetic correlations for ADG, and heritability were calculated over the continuous environmental range of -3σh to +3σh (SD of the HYM effect). The coheritability of ADG at the average environmental level and ADG in the environments along the -3σh to +3σh environmental gradient were also calculated. The analysis showed significant variation in macro-ES, revealing genotype by environment interactions (G × E) for ADG. The presence of G × E resulted in changes in additive genetic variance and heritability across the -3σh to +3σh range. The genetic correlations were high and positive between ADG in environments differing by 1σh units or less and decreased to moderately positive between ADG in the extreme environments in both sexes. The coheritability of ADG in the environment at the average level and the -3σh environment for boars were greater than the heritability in the environment at the average level, while it was less for gilts. The coheritability of ADG in the environment at the average level and the +3σh environment for boars was less than heritability in the environment at the average level, while it was either the same or greater for gilts, depending on the residual variance. Boars had larger additive genetic and residual variances than gilts. Heterogeneity of residual variances across herds was shown for both sexes. In conclusion, this study shows the presence of macro-ES, genetic variance heterogeneity among sexes for ADG in pigs, and residual variance heterogeneity across herds.

Additional file 2: Figure S2. Manhattan plot of GWAS in Yorkshire pigs for (a) FRONT, (b) BACK, (c) HIND and (d) CONF. The data provided represent the Manhattan plot of single-trait association analyses in Yorkshire pigs for four traits studied.

Additional file 3: Figure S3. Manhattan plot of GWAS in Duroc pigs for (a) FRONT, (b) BACK, (c) HIND and (d) CONF. The data provided represent the Manhattan plot of single-trait association analyses in Duroc pigs for four traits studied.

Additional file 4: Figure S4. Manhattan plot of within-breed multi-trait meta-analyses in (a) Landrace, (b) Yorkshire and (c) Duroc. The data provided represent the Manhattan plot of within-breed multi-trait meta-analyses in three breeds studied.

Additional file 1: Figure S1. Manhattan plot of GWAS in Landrace pigs for (a) FRONT, (b) BACK, (c) HIND and (d) CONF. The data provided represent the Manhattan plot of single-trait association analyses in Landrace pigs for four traits studied.

Additional file 5: Table S1. QTL regions and the most significant SNP within each region in across-breed meta-analyses. The data provided represent the QTL regions and the information of the most significant SNP within each region in across-breed meta-analyses.

In pigs litter size has increased during the last decades and number of weaned piglets is an important issue. The aim of this study was to develop a new trait of nurse capacity (NC) of crossbred sows viewed as crossbred performances in the two purebred parent lines, and estimate the genetic correlation to fertility and litter size five days after birth. An experiment recording phenotypes of crossbred sows was conducted in three large production herds with 11,247 first litter Danish Landrace x Yorkshire sows. All terminal sires used were Duroc AI boars. The experiment was running from 2010 to 2013. At farrowing, the total number born (TNB) was recorded. Five days after farrowing the litter size of the biological mother (LS5) was recorded. During the first three days after farrowing the number of piglets at each nurse sow was equalized to 14 piglets and after three weeks the NC was recorded and defined as the number of piglets nursed. Additional records on TNB and LS5 from related sows in nucleus and multiplier herds were added to obtain a data set with both purebred and crossbred information. A reduced animal model including both purebred and crossbred records was used and parameters were estimated. The results show that NC recorded on crossbred first litter sows had heritabilities of 0.05 and 0.07 for crossbred performance in the purebred populations of Landrace and Yorkshire, respectively. Estimated genetic correlations between TNB in purebreds and crossbreds show that nearly 50% of genetic gain in the purebred populations was transferred to crossbreds. Unfavorable genetic correlations between TNB in purebreds and NC in crossbreds were observed. For LS5 the genetic (co)variances show that 61% of the genetic gain in the two purebred lines was transferred to the commercial pig production of crossbred first litter sows, but no statistically significant genetic correlation to NC was obtained.

International audience; Crossbreding is predominant and intensively used in commercial meat production systems, especially in poultry and swine. Genomic evaluation has been successfully applied for breeding within purebreds but also offers opportunities of selecting purebreds for crossbred performance by combining information from purebreds with information from crossbreds. However, it generally requires that all relevant animals are genotyped, which is costly and presently does not seem to be feasible in practice. Recently, a novel single-step BLUP method for genomic evaluation of both purebred and crossbred performance has been developed that can incorporate marker genotypes into a traditional animal model. This new method has not been validated in real data sets. In this study, we applied this single-step method to analyze data for the maternal trait of total number of piglets born in Danish Landrace, Yorkshire, and two-way crossbred pigs in different scenarios. The genetic correlation between purebred and crossbred performances was investigated first, and then the impact of (crossbred) genomic information on prediction reliability for crossbred performance was explored. The results confirm the existence of a moderate genetic correlation, and it was seen that the standard errors on the estimates were reduced when including genomic information. Models with marker information, especially crossbred genomic information, improved model-based reliabilities for crossbred performance of purebred boars and also improved the predictive ability for crossbred animals and, to some extent, reduced the bias of prediction. We conclude that the new single-step BLUP method is a good tool in the genetic evaluation for crossbred performance in purebred animals.

A novel Horizontal model is presented for multitrait analysis of longitudinal traits through random regression analysis combined with single recorded traits. Weekly ADFI on test for Danish Duroc, Landrace, and Yorkshire boars were available from the national test station and were collected from 30 to 100 kg BW. Single recorded production traits of ADG from birth to 30 kg BW (ADG30), ADG from 30 to 100 kg BW (ADG100), and lean meat percentage (LMP) were available from breeding herds or the national test station. The Horizontal model combined random regression analysis of feed intake (FI) with single recorded traits of ADG100, LMP, and ADG30. In the Horizontal model, the FI data were horizontally structured with FI on each week as a "trait." The additive genetic and litter effects were modeled to be common across different FI records by reducing the rank of the covariance matrices using second- and first-order Legendre polynomials of age on test, respectively. The fixed effect and random residual variance were estimated for each weekly FI trait. Residual feed intake (RFI) was derived from the conditional distribution of FI given the breeding values of ADG100 and LMP. The heritability of FI varied by week on test in Duroc (0.12 to 0.19), Landrace (0.13 to 0.22), and Yorkshire (0.21 to 0.23). The heritability of RFI was lowest and highest in wk 6 (0.03) and 10 (0.10), respectively, in Duroc and wk 7 (0.04 and 0.02) and 1 (0.09 and 0.20), respectively, in Landrace and Yorkshire. The proportion of FI genetic variance explained by RFI ranged from 20 to 75% in Duroc, from 19 to 75% in Landrace, and from 11 to 91% in Yorkshire. Average daily gain from 30 to 100 kg BW and ADG30 heritabilities were moderate in Duroc (0.24 and 0.22, respectively), Landrace (0.34 and 0.25, respectively), and Yorkshire (0.34 and 0.22, respectively). Lean meat percentage heritability was moderate in Duroc (0.37) and large in Landrace (0.62) and Yorkshire (0.60). The genetic correlation of FI with ADG100 increased by week on test followed by a 32% decrease from wk 7 in Duroc and a 7% decrease in dam line breeds. Defining RFI as genetically independent of production traits leads to consistent and easy interpretable breeding values. The genetic parameters of traits in the feed efficiency complex and their dynamics over the test period showed breed differences that could be related to the fatness and growth potential of the breeds. The Horizontal model can be used to simultaneously analyze repeated and single recorded traits through proper modeling of the environmental variances and covariances.

Genomic selection has offered a new paradigm for livestock breeding within purebred populations, but it also offers greater opportunities for incorporating information from crossbred individuals and selection for crossbred performance. Wei and van der Werf (1994) presented a model for genetic evaluation using information from both purebred and crossbred animals for a two-breed crossbreeding system. The model provides breeding values for both purebred and crossbred performances. However, an extension of that model to incorporate genomic data has not been made yet. Here, a single-step method for genomic evaluation of both purebred and crossbred performances is presented. The model is on the one hand a reformulation and extension of the model by Wei van der Werf (1994), and on the other hand it extends previously studied genomic models for crossbred animals to include phenotypes on purebred animals and incorporate information on non-genotyped animals

A 30° Green Magnet based on permanent NdFeB magnets has been developed and installed in the injection line at the ASTRID2 synchrotron light source. The cost efficient design is optimized for a 1 T field at a length of 1 m using shaped iron poles to surpass the required field homogeneity. The inherent temperature dependence of NdFeB has been passively compensated to below 30 ppm/°C. A study of potential demagnetization effects has been performed by irradiation of NdFeB samples placed directly in a 100 MeV e-beam. A high permanent magnet work point was found to result in enhanced robustness, and the risk of demagnetization was found to be negligible for typical synchrotron applications. The magnet has successfully been in operation at ASTRID2 since autumn 2013., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

Selection for litter size at d 5 after farrowing (LS5) was introduced in 2004 to increase the number of piglets weaned and to reduce piglet mortality in Danish Landrace and Yorkshire. The objective of this study was to investigate selection responses for LS5, total number born (TNB), and mortality [MORT, defined as (TNB - LS5)/TNB] when selection for increasing LS5 was a part of the breeding goal. Data were collected from nucleus herds recorded from 2004 to 2010, including first litters of 42,807 Landrace sows and 33,225 Yorkshire sows. The data were analyzed using a 3-trait animal model of TNB, MORT, and LS5. Significant (co) variances were estimated between the 3 traits in both populations. The heritabilities of TNB, MORT, and LS5 were 0.10, 0.09, and 0.09 in Landrace and 0.12, 0.10, and 0.10 in Yorkshire. The genetic correlations were 0.28 and 0.22 between TNB and MORT, 0.74 and 0.68 between TNB and LS5, and -0.43 and -0.57 between MORT and LS5 in Landrace and Yorkshire, respectively. The results show that the genetic improvement of LS5 was a combination of increased TNB and reduced MORT. During the observation period, the genetic improvement was 1.7 piglets per litter for LS5, 1.3 piglets per litter for TNB, and 4.7% for MORT in Landrace and 2.2 piglets per litter, 1.9 piglets per litter, and 5.9% in Yorkshire. Phenotypic improvement was 1.4 piglets per litter for LS5, 0.3 piglets per litter for TNB, and 7.9% for MORT in Landrace and 2.1 piglets per litter, 1.3 piglets per litter, and 7.6% in Yorkshire. In addition, genetic gain was evaluated in 3 phenotypic groups of TNB, representing the 25% smallest litters, the 50% medium litters, and the 25% largest litters. In all 3 groups, the genetic and phenotypic gains of TNB and LS5 increased, whereas MORT reduced in both populations.

Feed conversion ratio (FCR) is an economically important trait in pigs and feed accounts for a significant proportion of the costs involved in pig production. In this study we used a high density SNP chip panel, Porcine SNP60 BeadChip, to identify association between FCR and SNP markers and to study the genetic architecture of the trait. After quality control, a total of 30,847 SNPs that could be mapped to the 18 porcine autosomes (SSC) following the pig genome assembly 10.2, were used in the analyses. Deregressed estimated breeding value was used as the response variable. A total of 3,071 Duroc pigs had both FCR data and genotype data. The linkage disequilibrium (r2) between adjacent markers was 0.56. Two association mapping approaches were used: linear mixed model (LMM) based on single locus regression analysis and a Bayesian variable selection approach (BVS). A total of 79 significant (p < 0.0001) SNP associations on six chromosomes were identified by LMM analyses. Out of these, ten SNPs crossed the genome-wide significance threshold. These ten SNPs were all located on the chromosomes 4 and 14. In the BVS analysis, a total of 44 SNPs located on 12 chromosomes had posterior probability more than or equal to 0.05, i.e. Bayes factor ≥ 10. Thirteen SNPs were identified both by LMM and BVS. These 13 SNPs were located on four chromosomes 4, 7, 8 and 14. Hypoxia inducible factor 1, alpha subunit inhibitor (HIF1AN) and Ladybird homeobox 1 (LBX1) are two possible candidate genes affecting FCR on chromosomes 4 and 14, respectively. The study provides a list of SNPs associated with FCR and also offers valuable information on the genetic architecture and candidate genes for this trait

We reasoned that there are diminishing marginal returns from genomic selection as the proportion of genotyped selection candidates is increased and breeding values based on a priori information are used to choose the candidates that are genotyped. We tested this premise by stochastic simulation of breeding schemes that resembled those used for pigs. We estimated rates of genetic gain and inbreeding realized by genomic selection in breeding schemes where candidates were phenotyped before genotyping and 0-100% of the candidates were genotyped based on predicted breeding values. Genotypings were allocated to male and female candidates at ratios of 100:0, 75:25, 50:50, 25:75, and 0:100. For genotyped candidates, a direct-genomic value (DGV) was sampled with reliabilities 0.10, 0.50, and 0.90. Ten sires and 300 dams with the highest breeding values after genotyping were selected at each generation. Selection was for a single trait with heritability 0.20. We found that the marginal returns did diminish as the genotyping proportion was increased, while the rate at which the returns diminished slowed as the DGV became more reliable. With DGV reliability 0.10, genotyping as little as 5% of the selection candidates realized 86% of the additional genetic gain and 67% of the reduction in inbreeding that was realized by genotyping 100% of the candidates. All of the genetic gain and reduction in inbreeding was realized by genotyping 40 and 50% of the candidates. When the reliability was increased to 0.90, genotyping 20% of the candidates was required to realize 76% of the genetic gain and 85% of the reduction in inbreeding. Genotyping 50% of the selection candidates with DGV reliability 0.90 realized 91% of the genetic gain and 94% of the reduction in inbreeding. Regardless of the DGV reliability, returns at low genotyping proportions of 0.5-10% were maximized when only male candidates were genotyped. At the high genotyping proportions of 20-50%, returns were maximized by genotyping both males and females. Our findings indicate that, provided a priori information is available, only 5-20% of the selection candidates need to be genotyped to realize most of the benefits from genomic selection. At these genotyping proportions, it is best to target males in schemes when the selection intensity for males is greater than females. Our findings should be welcomed by breeders because they suggest that large investments in genotyping are not required to reap most of the benefits from genomic selection

Breeding for increased litter size in Danish Landrace and Yorkshire started in 1992. Since then, litter size has in-creased significantly. Commercial pig producers and nucleus breeders argue that increases in litter size increase the number of dead piglets. Pig breeders in Denmark responded by including the total number of live piglets at day five (TN5) in the breeding goal. The objective of this study was to investigate whether breeding for TN5 has affected total number of born (TNB) and the mortality rate in five-day-old piglets. Data included records of first litter from 43,432 Landrace sows and 34,446 Yorkshire sows in Danish nucleus herds from January 2004 to December 2010. At far-rowing, litter size was recorded as TNB including number of still-births.Litter size and mortality rate up to day five after birth were analyzed using a two-trait animal model assuming normality. The heritabilities of maternal effect on litter size were 0.079 and 0.095 in Landrace and Yorkshir e. The heritabilities of maternal effect on piglet-mortality rates were 0.069 and 0.082 in Landrace and Yorkshire. The genetic correlation between litter size and mortality rate were unfavourable; and the estimates were 0.36 and 0.25 for the Landrace and Yorkshire. These findings indicate that breeding for TNB has increased the mortality rate from 1991 to 2004. However the introduction of TN5 in the breeding goal reduced mortality. The annual means of BLUP values related to piglet mortality showed that the ge-netic gain has reduced the piglet mortality rate by 4 %-points in Landrace and Yorkshire from 2004 to 2010. The genetics gain was confirmed by decreased phenotypic annual mortality rates in the breeding and multiplier herds.

An elimination programme was carried out to remove the dominant Rendement Napole mutation (RN−) from Danish Hampshire pigs. We reasoned that during and after the elimination of the RN− allele, genetic gain of production traits decreased while rate of inbreeding in the population increased compared to the period prior to elimination. The hypothesis was tested by estimating the genetic gain in seven production traits and measuring the rate of inbreeding in the population prior to and during the elimination period. Genetic gain was reduced for quantitative traits daily gain30–100 kg and feed conversion ratio, while gain for ultimate-pH, lean meat percentage and slaughter loss were increased slightly. There were no changes in genetic gain for daily gainbirth–30 kg and conformation. RN polymorphism affected several of the quantitative traits. The RN− mutation had a dominant effect on the traits daily gainbirth–30 kg, daily gain30−100 kg, slaughter loss, lean meat percentage and ultimate-pH. It exhibited overdominance for feed conversion ratio and additive effect for conformation. Rate of inbreeding decreased during the elimination of RN−. Our findings indicate that the consequences of the elimination programme were not as serious as were feared and that a carefully designed preselection strategy may avoid unacceptable loss of genetic gain and excessive loss of genetic variation

I et globaliseret, senmoderne, hyperkomplekst samfund præget af refleksion og metarefleksion vinder m°albarhed frem som kvalitativt parameter i forhold til fænomener som undervisning og læring. Dette kan ses som en konsekvens af at vi ikke fuldt ud forst°ar de bagvedliggende mekanismer og derfor med udgangspunkt i New Public Management-tænkning definerer læring ud fra et kriterium om m°alopfyldelse. Specialet tager med udgangspunkt i denne og afledte problemstillinger livtag med musikfagets aktuelle position i det almene gymnasium med en overordnet p°astand om markedsorienterede diskursers indflydelse p°a tænkningen af uddannelsessystemets form°al og indretning som indirekte °arsag til reformens nedprioritering af faget og som en fortsat udfordring i kampen for et musikfagligt tilbud i gymnasiet., Music in the Gymnasium. Set of assumptions and terms in music education through a discourse analytical approach.

Det er med det nuværende maskinelle tælleudstyr i de danske vejforvaltninger kun muligt at køretøjsklas- sificere ud fra køretøjets længde, og køretøjstypen kan ikke bestemmes nærmere. F.eks. er det umuligt at adskille personbiler med campingvogn, varebiler, busser og sololastbiler ud fra længden. Vejdirektoratet gennemfører derfor et program med løbende manuelle tællinger for bl.a. at kunne opfylde krav om statistik vedrørende trafikarbejdets fordeling på køretøjstyper. Den nuværende fremgangsmåde er både ressourcekrævende og usikker. I de senere år er teknologien til maskinel køretøjsklassifikation imidlertid blevet væsentlig forbedret ved hjælp af en mere intelligent udnyttelse af det elektriske impulsmønster. Teknologien benytter spoler som det nuværende tælleudstyr i Danmark og åbner således mulighed for at imødekomme et stigende behov for mere præcis og detaljeret viden om trafikken. Vejdirektoratet har derfor iværksat en undersøgelse med formål: • At undersøge om teknologien kan anvendes på eksisterende danske spoler. • At undersøge hvorvidt den danske køretøjspark kræver justering af den foreliggende teknologi eller justering af inddelingen i køretøjsklasser. • At undersøge om præcisionen i klassifikationen lever op til danske krav. • At undersøge anvendelighed og præcision i forskellige trafikmiljøer., Proceedings from the Annual Transport Conference at Aalborg University, Vol. 1 No. 1 (2004): Proceedings from the Annual Transport Conference at Aalborg University