Data/hora: 02/06/2024 01:03:06

Provedor de dados: 	96	
País: 	Brazil	
Título: 	Generalized linear mixed models for the genetic evaluation of binary reproductive traits: a simulation study	
Autores: 	Garcia,Diogo Anastácio; Pereira,Idalmo Garcia; Fonseca e Silva,Fabyano; Rosa,Guilherme Jordão de Magalhães; Pires,Aldrin Vieira; Leandro,Roseli Aparecida.	
Data: 	2012-01-01	
Ano: 	2012	
Palavras-chave: 	Beef cattle; Early pregnancy; Genetic parameters; GLMM; Link function.	
Resumo: 	The objective of this study was to evaluate the use of probit and logit link functions for the genetic evaluation of early pregnancy using simulated data. The following simulation/analysis structures were constructed: logit/logit, logit/probit, probit/logit, and probit/probit. The percentages of precocious females were 5, 10, 15, 20, 25 and 30% and were adjusted based on a change in the mean of the latent variable. The parametric heritability (h²) was 0.40. Simulation and genetic evaluation were implemented in the R software. Heritability estimates (ĥ²) were compared with h² using the mean squared error. Pearson correlations between predicted and true breeding values and the percentage of coincidence between true and predicted ranking, considering the 10% of bulls with the highest breeding values (TOP10) were calculated. The mean ĥ² values were under- and overestimated for all percentages of precocious females when logit/probit and probit/logit models used. In addition, the mean squared errors of these models were high when compared with those obtained with the probit/probit and logit/logit models. Considering ĥ², probit/probit and logit/logit were also superior to logit/probit and probit/logit, providing values close to the parametric heritability. Logit/probit and probit/logit presented low Pearson correlations, whereas the correlations obtained with probit/probit and logit/logit ranged from moderate to high. With respect to the TOP10 bulls, logit/probit and probit/logit presented much lower percentages than probit/probit and logit/logit. The genetic parameter estimates and predictions of breeding values of the animals obtained with the logit/logit and probit/probit models were similar. In contrast, the results obtained with probit/logit and logit/probit were not satisfactory. There is need to compare the estimation and prediction ability of logit and probit link functions.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982012000100008	
Editor: 	Sociedade Brasileira de Zootecnia	
Relação: 	10.1590/S1516-35982012000100008	
Formato: 	text/html	
Fonte: 	Revista Brasileira de Zootecnia  v.41 n.1 2012	
Fonte: 	info:eu-repo/semantics/openAccess