Genotype-by-environment (G × E) interactions could play an important role in cattle populations, and it should be considered breeding programmes to select the best sires for different environments. The objectives of this study were G E female fertility traits Danish Holstein dairy population using a reaction norm model (RNM), detect particular genomic regions contributing performance these interactions. In total 4534 bulls genotyped by Illumina BovineSNP50 BeadChip. An RNM with...

The objective of this study was to evaluate a genomic breeding scheme in small dairy cattle population that intermediate terms using both young bulls (YB) and progeny-tested (PB). This compared with conventional progeny testing program without use information and, as the extreme case, juvenile information, where all were used before available. structure, cost, plan parameters chosen reflect Danish Jersey population, being representative for population. consisted 68,000 registered cows....

The objective of the present study was to examine whether genomic selection females interacts with use reproductive technologies (RT) increase annual monetary genetic gain (AMGG). This tested using a factorial design 3 factors: (0 or 2,000 genotyped heifers per year), RT 50 donors selected at 14 mo age for producing 10 offspring), and 2 reliabilities prediction. In addition, different strategies how interact reliability prediction were investigated stochastic simulation by varying (1) number...

Small dairy breeds are challenged by low reliabilities of genomic prediction. Therefore, we evaluated the effect including cows in reference population for small cattle populations with a limited number sires population. Using detailed simulations, 2 types scenarios maintaining and updating over period 15yr were investigated: turbo scheme exclusively using genotyped young bulls hybrid mixed use progeny-tested bulls. Two modifications (1) per year was tested at 6 levels: 15, 40, 60, 100, 250,...

This study aimed to investigate dairy cattle breeding goals with more emphasis on resilience. We simulated the consequences of increasing weight resilience indicators and an assumed true trait (TR). Two environments different were represent variability production systems across Europe. Ten scenarios stochastically in a so-called pseudogenomic simulation approach. showed that many modern most likely have negative genetic gain for TR promising such as log-transformed, daily deviation from...

In this study a 3-dimensional (3D) camera system was set up to measure individual feed intake of dairy cows in commercial in-house setting. The developed identify the while eating, predict body weight based on curvature back cow, and quantify amount eaten by cow at each visit eating. identification recognizing patterns, colors, curvatures from reference database obtained corridor after milking, where images were taken all with simultaneous reading electronic ear tag. Body is predicted using...

In order to optimize the use of genomic selection in breeding plans, it is essential have reliable estimates values. This study investigated reliabilities direct values (DGVs) Jersey population estimated by three different methods. The validation methods were (i) fivefold cross-validation and (ii) on most recent 3 years bulls. reliability DGV was assessed using squared correlations between deregressed proofs (DRPs). 3-year model, also used assess DGV. data set consisted 1003 Danish bulls...

The main purpose of this study was to evaluate whether the population structure in Danish Jersey (DJ) known from history breed also is reflected its genomic structure. This done by comparing linkage disequilibrium and persistence phase for subgroups animals with high proportions (DNK) or United States (USJ) origin. Furthermore, it investigated a model explicitly incorporating origin animals, inferred either through pedigree SNP marker data, leads improved predictions compared ignoring...

In recent years, Genomic Selection (GS) has accelerated genetic gain in dairy cattle breeds worldwide. Despite the evident progress, several populations have also encountered challenges such as heightened inbreeding rates and reduced effective population sizes. The challenge been to find a balance between achieving substantial while managing diversity within population, thereby mitigating negative effects of depression. This study aims elucidate impact GS on pedigree genomic (ΔF) coancestry...

Decreased calving performance not only directly impacts the economic efficiency of dairy cattle farming but also influences public concern for animal welfare. Previous studies have revealed a QTL on Bos taurus autosome (BTA) 18 that has large effect traits in Holstein cattle. In this study, fine mapping was performed using imputed high-density SNP chip (HD) genotypes followed by next-generation sequencing (NGS) variants. BTA18 scanned seven direct 6113 bulls with HD genotypes. rs136283363...

In this study, we explored mating allocation in Holstein using genomic information for 24,333 females born Denmark, Finland, and Sweden. We used 2 data sets of bulls: the top 50 genotyped bulls 25 polled on Nordic total merit scale. linear programming to optimize economic scores within each herd, considering genetic level, relationship, semen cost, impact defects, polledness, β-casein. found that it was possible reduce relationships eliminate expression defects with minimal effect level...

Abstract Background After the extensive implementation of genomic selection (GS), choice statistical model and data used to estimate variance components (VCs) remains unclear. A primary concern is that VCs estimated from a traditional pedigree-based animal (P-AM) will be biased due ignoring impact GS. The objectives this study were examine effects GS on estimates VC in analysis different sets phenotypes investigate estimation using methods. Data simulated resemble Danish Jersey population....

Genotype × environment interaction (G E) is of increasing importance for dairy cattle breeders due to international multiple-environment selection animals as well the differentiation production environments within countries. This theoretical simulation study tested hypothesis that genomic (GS) breeding programs realize larger genetic benefits by cooperation in presence G E than conventional pedigree-based (PS) programs. We simulated two each with their own population and environment. Two...

The aim of this study was to characterize preferences farmers for breeding goal traits with Danish Red (DR) or Jersey (DJ) cows. A breed-specific survey established farmers’ improvements in 10 traits, by means pairwise rankings using the online software 1000Minds. These were based on equal economic worth trait improvements. DR filled 87 and DJ 76 farmers. Both gave highest preference mastitis, lowest calving difficulty. By a cluster analysis, three distinct clusters identified per breed....

In this study, we compared mating allocations in Nordic Red Dairy Cattle using genomic information. We used linear programming to optimize different economic scores within each herd, considering genetic level, semen cost, the impact of recessive defects, and relationships. selected 9,841 genotyped females born Denmark, Finland, or Sweden 2019 for allocations. 2 pedigree relationship coefficients, first tracing 3 generations back from parents potential second based on all available 1...