Data/hora: 17/06/2024 08:07:28

Biblioteca(s): 	Embrapa Pecuária Sul.	
Data corrente: 	24/07/2019	
Data da última atualização: 	01/10/2019	
Autoria: 	CAMPOS, G. S.; REIMANN, F. A.; SCHIMDT, P. I.; CARDOSO, L. L.; SOLLERO, B. P.; BRACCINI, J.; YOKOO, M. J. I.; BOLIGON, A. A.; CARDOSO, F. F.	
Afiliação: 	G. S. Campos, UFPEL; F. A. Reimann, UFPEL; P. I. Schimdt, UFPEL; L. L. Cardoso; BRUNA PENA SOLLERO, CPPSUL; J. Braccini, UFRGS; MARCOS JUN ITI YOKOO, CPPSUL; A. A. Boligon, UFPEL; FERNANDO FLORES CARDOSO, CPPSUL.	
Título: 	Threshold and linear models for genetic evaluation of visual scores in Hereford and Braford cattle.	
Ano de publicação: 	2019	
Fonte/Imprenta: 	Animal Production Science, v. 59, n. 4, p. 619-627, 2019.	
DOI: 	doi.org/10.1071/AN17436	
Idioma: 	Inglês	
Conteúdo: 	Data from 127&#8201;539 Hereford and Braford cattle were used to compare estimates of genetic parameters for navel, conformation, precocity, muscling and size visual scores at yearling, using linear and threshold animal models. In a second step, these models were cross-validated using a multinomial logistic regression in order to quantify the association between phenotype and genetic merit for each trait. For navel score, higher heritability was obtained with the threshold model (0.42 ± 0.02) in relation to the linear model (0.22 ± 0.02). However, similar heritability was estimated in both models for conformation, precocity, muscling and size, with values of 0.18 ± 0.01, 0.19 ± 0.01, 0.19 ± 0.01 and 0.26 ± 0.01, respectively, using linear model, and of 0.19 ± 0.01, 0.19 ± 0.01, 0.20 ± 0.01, and 0.29 ± 0.01, respectively, using threshold model. For navel score, Spearman correlations between sires? breeding values predicted using linear and threshold models ranged from 0.60 (1% of the best sires are selected) to 0.96 (all sires are selected). For conformation, precocity, muscling and size scores, low changes in sires? rank are expected using these models (Spearman correlations >0.86), regardless of the proportion of sires selected. Except for navel with the linear model, the direction of the associations between phenotype and genetic merit were in accordance with its expectation, as there were increases in the phenotype per unit of change in the breeding value. Thus, the threshold model would be recommended to perform genetic evaluation of navel score in this population. However, linear and threshold models showed similar predictive ability for conformation, precocity, muscling and size scores.	
Palavras-Chave: 	Inferência bayesiana.	
Thesagro: 	Criação; Gado de Corte; Melhoramento Genético Animal.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Pecuária Sul (CPPSUL)	
Exemplares: 	CPPSUL - (14554-1) - UPC - AP - DD -  -  -  - DIS