|
|
|
|
|
| Sousa Júnior,Severino Cavalcante de; Faro,Lenira El; Bignardi,Annaiza Braga; Cardoso,Vera Lucia; Machado,Paulo Fernando; Albuquerque,Lucia Galvão de. |
| Foram utilizadas 3.202 primeiras lactações de vacas da raça Holandesa de quatro fazendas da região Sudeste, para verificar a influência da estrutura de dados de produção de leite sobre os parâmetros genéticos. Foram testados quatro arquivos com diferentes estruturas: controles semanais (CS), arquivo mensal (CM), bimestral (CB) e trimestral (CT), com 122.842, 30.883, 15.837 e 12.702 controles, respectivamente. Um modelo de regressão aleatória foi empregado nas análises, considerando os efeitos genético aditivo e o de ambiente permanente de animal, como aleatórios. Os efeitos fixos, grupos de contemporâneos (GC) foram comuns para todos os arquivos de dados e foram compostos por fazenda, mês e ano do controle, além da co-variável idade da vaca ao parto... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Avaliação genética; Bovinos de leite; Dados longitudinais. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782014001102058 |
| |
|
|
| Cruz,Diego Augusto Campos da; Savegnago,Rodrigo Pelicioni; Santana,Annaíza Braga Bignardi; Peixoto,Maria Gabriela Campolina Diniz; Bruneli,Frank Angelo Tomita; Faro,Lenira El. |
| ABSTRACT: The aim of this study was to explore the pattern of genetic lactation curves of Guzerá cattle using cluster analysis. Test-day milk yields of 5,274 first-lactation Guzerá cows were recorded in a progeny test. A total of 34,193 monthly records were analyzed with a random regression animal model using Legendre polynomials to fit additive genetic and permanent environmental random effects and mean trends. Hierarchical and non-hierarchical cluster analyses were performed based on the EBVs for monthly test-day milk yield, peak yield, lactation persistency, and partial cumulative and 305-day yields. The heritability estimates for test-day milk yields ranged from 0.24 to 0.52. Cluster analysis identified animals in the population that belong to... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Breeding values; Lactation curve; Random regression. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782016000701281 |
| |
|
| |
|
|
| Oliveira,Elisa Junqueira; Savegnago,Rodrigo Pelicioni; Freitas,Luara Afonso de; Freitas,Anielly Paula; Maia,Suellen Rodrigues; Simili,Flávia Fernanda; Faro,Lenira El; Costa,Ricardo Lopes Dias da; Santana Júnior,Mário Luiz; Paz,Claudia Cristina Paro de. |
| Abstract: The objective of this work was to estimate genetic parameters for traits related to resistance to endoparasites in Santa Inês sheep, for a possible inclusion in sheep breeding programs, as well as to evaluate the additive genetic pattern of the animals using cluster analyzes, in order to assess whether there are groups within the population that can be used as candidates for selection for resistance to endoparasites. The studied traits were: Famacha score, fecal egg counts (FEC), packed cell volume (PCV), total plasma protein (TPP), body condition score (BCS), and body weight (BW). Heritability estimates ranged from 0.17 (0.05) for TPP to 0.31 (0.07) for BCS. The cluster analyzes based on the breeding values identified four clusters. Famacha and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cluster analysis; Famacha; Genetic correlation; Heritability; K-means; Multivariate analysis. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2018001201338 |
| |
|
|
| Fernandes,André Rabelo; Faro,Lenira El; Vercesi Filho,Anibal Eugênio; Machado,Carlos Henrique Cavallari; Barbero,Leandro Martins; Bittar,Eustáquio Resende; Igarasi,Mauricio Scoton. |
| ABSTRACT The objective of this study was to analyze the genetic evolution of milk production, udder morphology, and animal behavior of Gir dairy cattle. Data were obtained on the predicted breeding values for milk yield of 60,226 cows born from 1968 to 2015 and standardized predicted breeding values for udder conformation and milking behavior of 7,635 cows born from 1987 to 2015. The influence of tested bulls on genetic trends was discussed, with special focus on the period after 1993, the year when the predicted breeding values of the first group of tested bulls were released. The traits of interest were 305-d milk yield, fore udder attachment, rear udder height, rear udder width, teat length, teat thickness, ease of milking, and reactivity. Significant... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Linear traits; Mammary system; Reactivity; Teat morphology; Udder attachment. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982019000100304 |
| |
|
|
| Pereira,Rodrigo Junqueira; Ayres,Denise Rocha; Santana Junior,Mário Luiz; Faro,Lenira El; Vercesi Filho,Aníbal Eugênio; Albuquerque,Lucia Galvão de. |
| Abstract: The objective of this work was to compare genetic evaluations of milk yield in the Gir breed, in terms of breeding values and their accuracy, using a random regression model applied to test-day records or the traditional model (TM) applied to estimates of 305-day milk yield, as well as to predict genetic trends for parameters of interest. A total of 10,576 first lactations, corresponding to 81,135 test-day (TD) records, were used. Rank correlations between the breeding values (EBVs) predicted with the two models were 0.96. The percentage of animals selected in common was 67 or 82%, respectively, when 1 or 5% of bulls were chosen, according to EBVs from random regression model (RRM) or TM genetic evaluations. Average gains in accuracy of 2.7, 3.0,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Accuracy; Persistency; Random regression; Rank correlation. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2019000104305 |
| |
|
|
|
