14 documents found, page 1 of 2
Genotype imputation strategies for Portuguese Holstein cattle using different S...
SILVA, A. A.; SILVA, F. F.; SILVA, D. A.; SILVA, H. T.; COSTA, C. N.; LOPES, P. S.; VERONEZE, R.; THOMPSON, G.; CARVALHEIRA, J.Abstract: Although several studies have investigated the factors affecting imputation accuracy, most of these studies involved a large number of genotyped animals. Thus, results from these studies cannot be directly applied to small populations, since the population structure affects imputation accuracy. In addition, factors affecting imputation accuracy may also be intensified in small populations. Therefore, ...
Genomic prediction for additive and dominance effects of censored traits in pigs.
SANTOS, V. S.; MARTINS FILHO, S.; RESENDE, M. D. V. de; AZEVEDO, C. F.; LOPES, P. S.; GUIMARÃES, S. E. F.; SILVA, F. F.Age at the time of slaughter is a commonly used trait in animal breeding programs. Since studying this trait involves incomplete observations (censoring), analysis can be performed using survival models or modified linear models, for example, by sampling censored data from truncated normal distributions. For genomic selection, the greatest genetic gains can be achieved by including non-additive genetic effects ...
Regularized quantile regression for SNP marker estimation of pig growth curves.
BARROSO, L. M. A.; NASCIMENTO, M.; NASCIMENTO, A. C. C.; SILVA, F. F.; SERÃO, N. V. L.; CRUZ, C. D.; RESENDE, M. D. V. de; SILVA, F. L.; AZEVEDO, C. F.Background: Genomic growth curves are generally defined only in terms of population mean; an alternative approach that has not yet been exploited in genomic analyses of growth curves is the Quantile Regression (QR). This methodology allows for the estimation of marker effects at different levels of the variable of interest. We aimed to propose and evaluate a regularized quantile regression for SNP marker effect...
Multi-trait and repeatability models for genetic evaluation of litter traits in...
COSTA, E. V.; VENTURA. H. T.; FIGUEIREDO, E. A. P. de; SILVA, F. F.; GLÓRIA, L. S.; GODINHO, R. M.; RESENDE, M. D. V. de; LOPES, P. S.Abstract: We aimed to compare multi-trait and repeatability models to estimate genetic parameters for the traits number of piglets born alive (NBA) and alive at 3 week of age (NP3), litter weight at birth (LW0) and at 3 week of age (LW3), and mean piglet weight at birth (MW0) and at 3 week of age (MW3), considering the first three farrowings of Landrace sows. Heritability (h2) estimates showed an increasing pat...
Expressed sequenced tags profiling of resistant and susceptible Gyr x Holstein ...
NASCIMENTO, C. S.; MACHADO, M. A.; GUIMARÃES, S. E. F.; MARTINS, M. F.; PEIXOTO, J. de O.; FURLONG, J.; PRATA, M. C. de A.; VERNEQUE, R. da S.Tick resistance in cattle is mainly found in zebu (Bos indicus) animals, although it is also present in some taurine (B. taurus) breeds. In order to characterize functional genes involved in tick resistance/susceptibility in cattle, two cDNA libraries were generated using skin tissues of selected Holstein x Gyr animals. A total of 2700 high-quality reads from both resistant and susceptible cDNA were assembled i...
Random regression models for the estimation of genetic and environmental covari...
SARMENTO, J. L. R.; TORRES, R. A.; SOUSA, W. H.; LOBO, R. N. B.; ALBUQUERQUE, L. G.; LOPES, P. S.; SANTOS, N. P. S.; BIGNARD, A. B.Abstract: Polynomial functions of different orders were used to model random effects associated with weight of Santa Ines sheep from birth to 196 days. Fixed effects included in the models were contemporary groups, age of ewe at lambing, and fourth-order Legendre polynomials for age to represent the average growth curve. In the random part, functions of different orders were included to model variances associat...
Association between G316A growth hormone polymorphism and economic traits in pigs.
FARIA, D. A. de; GUIMARÃES, S. E. F.; LOPES, P. S.; PIRES, A. V.; PAIVA, S. R.; SOLLERO, B. P.; WENCESLAU, A. A.Made available in DSpace on 2018-06-05T00:37:19Z (GMT). No. of bitstreams: 1 ID276201.pdf: 145785 bytes, checksum: 37e3ec1b566d51d1715d74bff6a5bb80 (MD5) Previous issue date: 2006-12-18
Bayesian model combining linkage and linkage disequilibrium analysis for low de...
SILVA, F. F.; JEREZ, E. A. Z.; RESENDE, M. D. V. de; VIANA, J. M. S.; AZEVEDO, C. F.; LOPES, P. S.; NASCIMENTO, M.; LIMA, R. O. de; GUIMARÃES, S. E. F.We combined linkage (LA) and linkage disequilibrium (LDA) analyses (emerging the term ?LALDA?) for genomic selection (GS) purposes. The models were fitted to a simulated dataset and to a real data of feed conversion ratio in pigs. Firstly, the significant QTLs (quantitative trait locus) were identified through LA-based mixed models considering the QTL-genotypes as random effects by means of genotypic identity b...
Mapping quantitative trait loci for performance traits on pig chromosome 6 (SSC6).
PIRES, A. V.; LOPES, P. S.; GUIMARAES, C. T.; GUIMARAES, S. E. F.The objective of this study was to perform QTL mapping associated with performance traits on swine chromosome 6 (SSC6). The F2 population was produced by outcrossing using two native Brazilian breed Piau sires and 18 commercial dams. A total of 617 F2 animals were genotyped for 13 microsatellite markers. The traits evaluated in the F2 population were teat number (TN), birth weight (BW), weight at 21, 42, 63, 77...
Genotype by environment interaction for tick resistance of Hereford and Braford...
MOTA, R. R.; TEMPELMAN, R. J.; LOPES, P. S.; AGUILAR, I.; SILVA, F. F.; CARDOSO, F. F.The cattle tick is a parasite that adversely affects livestock performance in tropical areas. Although countries such as Australia and Brazil have developed genetic evaluations for tick resistance, these evaluations have not considered genotype by environment (G*E) interactions. Genetic gains could be adversely affected, since breed-stock comparisons are environmentally dependent on the presence of G*E interact...