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| Registros recuperados: 177 | |
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| Tholon,P.; Queiroz,S.A.. |
| The objective of this work was to determine genetic parameters for body weight of tinamou in captivity. It was used random regression models in analyses of data by considering the direct additive genetic (DA) and permanent environmental effects of the animal (PE) as random effects. Residual variances were modeled by using a fifth-order variance function. The mean population growth curve was fitted by sixth-order Legendre orthogonal polynomials. Direct additive genetic effects and animal environmental permanent effect were modeled by using Legendre polynomials of order two to nine. The best results were obtained by models with orders of fit of 6 for direct additive genetic effect and of order 3 for permanent effect by Akaike information criterion and of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Genetic correlation; Heritability; Legendre polynomials; Tinamou; Wild bird. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982011000400011 |
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| Bertipaglia,Tássia Souza; Carreño,Luis Orlando Duitama; Machado,Carlos Henrique Cavallini; Andrighetto,Cristiana; Fonseca,Ricardo da. |
| The objective of this study was to evaluate the association of visual scores of body structure, precocity and muscularity with production (body weight at 18 months and average daily gain) and reproductive (scrotal circumference) traits in Brahman cattle in order to determine the possible use of these scores as selection criteria to improve carcass quality. Covariance components were estimated by the restricted maximum likelihood method using an animal model that included contemporary group as fixed effect. A total of 1,116 observations of body structure, precocity and muscularity were used. Heritability was 0.39, 043 and 0.40 for body structure, precocity and muscularity, respectively. The genetic correlations were 0.79 between body structure and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Average daily gain; Body weight at 18 months; Genetic correlation; Heritability; Scrotal circumference. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982012000600013 |
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| Malhado,Carlos Henrique Mendes; Malhado,Ana Claudia Mendes; Ramos,Alcides de Amorim; Carneiro,Paulo Luiz Souza; Souza,Julio César de; Pala,Akin. |
| The major objective of this study was to estimate heritability and genetic correlations between milk yield (MY) and calving interval (CI) and lactation length (LL) in Murrah buffaloes using Bayesian inference. The database used belongs to the genetic improvement program of four buffalo herds from Brazil. To obtain the estimates of variance and covariance, bivariate analyses were performed with the Gibbs sampler, using the program MTGSAM. The heritability coefficient estimates were 0.28, 0.03 and 0.15 for MY, CI and LL, respectively. The genetic correlations between MY and LL was moderate (0.48). However, the genetic correlation between MY and CI showed large HPD regions (highest posterior density interval). Milk yield was the only trait with clear... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Genetic correlation; Gibbs sampler; Heritability. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982013000800005 |
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| McManus,Concepta; Pinto,Bruno Freitas; Martins,Rafhael Felipe Saraiva; Louvandini,Helder; Paiva,Samuel Rezende; Braccini Neto,José; Paim,Tiago do Prado. |
| Three production systems for sheep (Low - L, Medium - M and High - H technology), with increasing technological levels, were studied under conditions in the Center-west of Brazil, to determine economic weights and selection indices of important traits. Receipts and costs were simulated using an economic simulator to calculate the structure of the operational costs. Only characteristics that were responsible for more than 10% of the profit were studied, which included: number of weaned lambs, food consumption (ewe and lamb), weight of carcass and weight of female lambs sold for reproduction. Regardless of the index used (profitability or yield) or system (L, M or H), the economic weights are larger for the number of lambs weaned per ewe. With improvement in... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Correlations; Costs; Heritability; Profit; Revenue. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982011001200014 |
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| Oliveira,Kassiana Adriano Pinto de; Lôbo,Raimundo Nonato Braga; Facó,Olivardo. |
| It was evaluated data set of 19,303 weight records of Santa Inês sheep in order to evaluate distinct polynomial functions with different order for better adjustements of fixed and random regressions of growth trajectory and to estimate (co)variances components and genetic parameters of this trajectory. Fixed effects used in analysis were contemporary group, sex and birth type. Ordinary and Legendre polynomials, ranging from two to four orders, were evaluated for fixed regression of average growth trajectory. Legendre and quadratic b-spline functions, ranging from three to four orders, were evaluated for random regressions. Legendre polynomials of order fourth were suitable to fit random regression, while ordinary polynomials of third order were the best... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Β-spline functions; Genetic correlation; Heritability; Legendre polynomials; Ordinary polynomials. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982010000500013 |
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| Claus,Luís Afonso Marques; Koetz Júnior,Celso; Roso,Vanerlei Mozaquatro; Borges,Marcelo Henrique Favaro; Barcellos,Júlio Otávio Jardim; Ribeiro,Edson Luis de Azambuja. |
| ABSTRACT This study aimed at estimating the heritability of age at first calving and of performance traits included in the selection index and the genetic correlations between age at first calving and these performance traits. Data were extracted from the Conexão Delta G database and only data from herds in which heifers were bred younger than 24 months of age were used, resulting in a file with 331,310 evaluated animals. The following traits were included in the analyses: age at first calving, birth to weaning gain, post-weaning weight gain, visual scores of conformation, precocity, and muscling evaluated at weaning and in yearling heifers. Covariance components were obtained by bi-character analyses between traits. An alternative age at first calving was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Beef cattle; Breeding; Heritability. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982017000400303 |
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| Sabedot,Mayara Andressa; Romano,Gabrieli de Souza; Pedrosa,Victor Breno; Pinto,Luís Fernando Batista. |
| ABSTRACT This study aimed to estimate the heritability of milk yield (MY), fat percent (F%), fat yield (FY), protein percent (P%), protein yield (PY), somatic cell score (SCS), and total bacterial count score (TBCS) as well as to estimate the genetic correlations among these traits, using a dataset from 5,918 lactations of Jersey cows in Brazil. The covariance components were estimated by restricted maximum likelihood using the PEST and VCE6 programs. The average values obtained for MY, F%, FY, P%, PY, SCS, and TBCS were 5017.5 kg, 4.3%, 192.3 kg, 3.3%, 173.0 kg, 5.9, and 2.9, respectively, while the heritability values were 0.16, 0.55, 0.18, 0.61, 0.25, 0.21, and 0.08, respectively. The genetic correlations ranged from low to high magnitude, with positive... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Genetic correlation; Heritability; Mastitis resistance; Selection. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982018000100408 |
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| Biassus,Igor de Oliveira; Cobuci,Jaime Araújo; Costa,Claudio Napolis; Rorato,Paulo Roberto Nogara; Braccini Neto,José; Cardoso,Leandro Lunardini. |
| Total numbers of 56,508, 35,091 and 8,326 records of milk, fat, and protein test-day yields, respectively, were used to estimate genetic parameters for six persistency measures on milk, fat and protein productions of Holstein cows reared in Minas Gerais state. Covariance components for additive genetic effects and permanent environmental effects were estimated by REML in random regression models using Legendre polynomials from the third to the sixth order. Overall, models with the highest orders of Legendre polynomials showed the best quality of adjustments of these productive records. Heritability estimates obtained by the models for persistence in milk, fat, and protein yields ranged from 0.04 to 0.32, from 0.00 to 0.23, and from 0.00 to 0.27,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Genetic correlation; Heritability; Legendre polynomials; Random regression model; Selection. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982010001200009 |
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| Scalez,Daiane Cristina Becker; Fragomeni,Breno de Oliveira; Santos,Dalinne Chrystian Carvalho dos; Passafaro,Tiago Luciano; Alencar,Maurício Mello de; Toral,Fabio Luiz Buranelo. |
| ABSTRACT The objective of this study was to estimate genetic parameters for body weight of beef cattle in performance tests. Different random regression models with quadratic B-splines and heterogeneous residual variance were fitted to estimate covariance functions for body weights of Nellore and crossbred Charolais × Nellore bulls. The criteria −2 residual log-likelihood (−2RLL), Akaike Information Criterion (AIC), and consistent AIC (CAIC) were used to choose the most appropriate model. For Nellore bulls, residual variance was modeled with six classes of age, and direct additive genetic and permanent environment effects were modeled with quadratic B-splines with two and one intervals, respectively. For crossbred bulls, quadratic B-splines with one... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Animal breeding; Bos indicus; Genetic correlation; Heritability. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982018000100407 |
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| Costa-Maia,Fabiana Martins; Toledo,Vagner de Alencar Arnaut de; Martins,Elias Nunes; Lino-Lourenço,Daniela Andressa; Sereia,Maria Josiane; Oliveira,Carlos Antonio Lopes de; Faquinello,Patrícia; Halak,André Luiz. |
| Genetic and phenotypic parameters considering the genetic effect on hygienic behavior of queen and workers from 40 Africanized honeybees colonies were estimated separately. Maternal origin of queens was controlled whereas the paternal was unknown, and different groups of workers were considered in three seasons, October 2006, April 2007 and August 2007, but with the same queen. Colonies were 21 honey producers and 19 royal jelly producers. After the method of freezing capped brood, hygienic behavior was determined by the ratio between the number of dead capped brood removed at 24, 48 and 72 hours and the total number of capped brood at zero hour. Data was submitted to single and three traits analyses using Bayesian inference. Estimates of direct... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Africanized honeybee queens; Bayesian inference; Genetic correlation; Heritability; Maternal effect; Removal of dead capped brood. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982011000900010 |
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| Boligon,Arione Augusti; Albuquerque,Lucia Galvão de; Mercadante,Maria Eugênia Zerlotti; Lôbo,Raysildo Barbosa. |
| Data from 23,120 Nellore animals were used to estimate genetic parameters for age at first calving, average gains from weaning to yearling and from yearling to after yearling, weaning weight, yearling weight, after yearling weight and weight at 2 and 5 years of age. Animal models were fitted by Restricted Maximum likelihood Method. Estimate heritability for age at first calving, weaning to yearling weight gain, yearling to after yearling weight gain, weight at weaning, yearling weight, after yearling weight and weight from 2 to 5 years of age were 0.17 ± 0.01; 0.23 ± 0.03; 0.25 ± 0.03; 0.28 ± 0.02; 0.26 ± 0.03; 0.30 ± 0.03; 0.32 ± 0.02 and 0.36 ± 0.04, respectively. The genetic correlation estimates between age at first calving and weight traits ranged... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Beef cattle; Genetic parameters; Heritability; Productive; Reproductive traits. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982010000400007 |
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| Sabedot,Mayara Andressa; Romano,Gabrieli de Souza; Pedrosa,Victor Breno; Pinto,Luís Fernando Batista. |
| ABSTRACT This study aimed to estimate the heritability coefficients for ten functional type traits and milk production in the Jersey breed in Brazil, besides the genetic and phenotypic correlations between them. The present study utilised data from 1,567 records of linear type traits, including stature (ST), body depth (BD), loin strength (LS), rump width (RW), rump angle (RA), fore udder attachment (FUA), front teat placement (FTP), rear udder height (RUH), central ligament (CL), and final score (FS). Milk yield (MY) adjusted to 305 lactation days was also calculated. Covariance components were estimated by the restricted maximum likelihood approach using the PEST and VCE6 programs on the animal model. Heritability coefficients thus assessed were as... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Dairy cattle; Genetic correlation; Heritability; Selection. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982018000100409 |
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| Sarmento,José Lindenberg Rocha; Torres,Robledo de Almeida; Sousa,Wandrick Hauss de; Albuquerque,Lucia Galvão de; Lôbo,Raimundo Nonato Braga; Sousa,José Ernandes Rufino de. |
| Polynomial functions of age of different orders were evaluated in the modeling of the average growth trajectory in Santa Ines sheep in random regression models. Initially, the analyses were performed not considering the animal effect. Subsequently, the random regression analyses were performed including the random effects of the animal and its mother (genetic and permanent environment). The linear fit was lower, and the other orders were similar until near 100 days of age. The cubic function provided the closest fit of the observed averages, mainly at the end of the curve. Orders superior to this one tended to present incoherent behavior with the observed weights. The estimated direct heritabilities, considering the linear fit, were higher to those... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Animal model; Breeding values; Fixed regression; Hairless sheep; Heritability; Polynomial functions. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982011000200012 |
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| Raidan,Fernanda Santos Silva; Tineo,Juan Salvador Andrade; Moraes,Mariana Mamedes de; Escarce,Thiago Campos; Araújo,Andresa Eva Melo de; Gomes,Muller Marques de Carvalho; Ventura,Henrique Torres; Toral,Fabio Luiz Buranelo. |
| ABSTRACT This study aimed to evaluate associations among final weight (FW), average daily gain (ADG), scrotal circumference (SC), and visual score (VS) of beef cattle in performance tests on pasture or in feedlots. Genetic parameters for FW, ADG, SC, and VS of young Nellore bulls performance-tested on pasture or in feedlots were evaluated by mixed model. The performance test and final age were considered as fixed effects and additive genetic and residual effects were considered as random effects. Additive genetic and residual variances for final weight and average daily gain were smaller on pasture than in feedlots. There was no difference between genetic and residual variances and heritability for scrotal circumference on pasture or in feedlots. Genetic... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bos indicus; Genetic correlation; Heritability; Phenotypic selection. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982017000400309 |
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| Hidalgo,André Marubayashi; Martins,Elias Nunes; Santos,Alexandre Leseur dos; Quadros,Thays Cristina Oliveira de; Ton,Ana Paula Silva; Teixeira,Rafael. |
| The objective of this research was to estimate genetic parameters for the traits egg weight, egg production in 189 days and age at first egg in three laying quails and one meat line of quails. Data was analyzed by Bayesian procedures using Gibbs sampling. The heritability estimates for egg weight, egg production in 189 days and age at first egg, were, respectively, for yellow line, 0.31, 0.84 and 0.53; for blue line, 0.14, 0.82 and 0.60; for red line, 0.70, 0.96 and 0.75; and for meat line, 0.73, 0.96 and 0.72. Genetic correlation between egg weight and egg production in 189 days, egg weight and day at first egg and egg production in 189 days and day at first egg were for yellow line, 0.58, -0.77 and -0.90; for blue line, 0.09, -0.01 and -0.95; for red... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Genetic correlation; Genetic variance; Heritability; Overlap probability; Quails. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982011000100013 |
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| Zambrano,Juan Carlos; Echeverri,Julián. |
| The objective of this study was to estimate the genetic, phenotypic and environmental parameters for calving interval (CI), days open (DO), number of services per conception (NSC) and conception rate (CR) in Holstein and Jersey cattle in Antioquia (Colombia). Variance and covariance component estimates were obtained by an animal model that was solved using the derivative-free restricted maximum likelihood method. The means and standard deviations for CI, DO, NSC and CR were: 430.32±77.93 days, 127.15±76.96 days, 1.58±1.03 services per conception and 79.88±28.66% in Holstein cattle, and 409.33±86.48 days, 125.62±86.09 days, 1.48±0.98 services per conception and 84.08±27.23% in Jersey cattle, respectively. The heritability estimates (standard errors) were:... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fertility; Genetic correlation; Heritability; Repeatability. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982014000300005 |
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| Tramonte,Nicole Colucci; Grupioni,Natalia Vinhal; Stafuzza,Nedenia Bonvino; Guidolin,Diego Gomes Freire; Savegnago,Rodrigo Pelicioni; Bezerra,Luiz Antonio Framartino; Lôbo,Raysildo Barbosa; Munari,Danísio Prado. |
| ABSTRACT The objectives of this study were to estimate genetic parameters and genetic trends and perform principal component analysis for the following traits: body weight adjusted at 210 days of age (W210), one year (W365), and yearling or 450 days of age (W450); weight gain from birth to weaning or 210 days of age (WGBW), from weaning to 365 days of age (WGW365), and from one year to yearling (WGY); and scrotal circumference adjusted at 365 (SC365) and 450 (SC450) days of age of Guzera beef cattle. Variance components were estimated under a two-trait animal model using the restricted maximum likelihood method. The fixed effects included in the model were birth season, contemporary group, and covariable age of dam at calving as linear and quadratic... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Animal breeding; Bos taurus indicus; Genetic correlation; Heritability. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982019000100308 |
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| Campos,Rafael Viegas; Cobuci,Jaime Araujo; Costa,Claudio Napolis; Braccini Neto,José. |
| Data from 26,558 Holstein cows in 802 herds were used to estimate genetic, residual and phenotypic parameters for 22 type traits. The model included the fixed effects of herd-year, period of classification, classifier, stage of lactation and age of cows at calving (covariate) and random genetic and residual effects. Heritability for type traits ranged from 0.10 to 0.39. The genetic variability in these traits suggested the possibility for moderate genetic gains through selection. The phenotypic correlations were moderated, mainly in the section conformation. Genetic correlations between type traits ranged from -0.44 to 0.85. High genetic correlations indicated that breeding programs could be successful without including all type traits. The selection for... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: (co)variance components; Dairy cattle; Genetic correlations; Heritability; REMLF90; Selection. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982012001000003 |
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| Registros recuperados: 177 | |
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