Title:	Effect of inclusion or non-inclusion of short lactations and cow and/or dam genetic group on genetic evaluation of Girolando dairy cattle.
Authors:	CANAZA-CAYO, A. W. SILVA, M. V. G. B. COBUCI, J. A. MARTINS, M. F. LOPES, P. S.
Affiliation:	ALI WILLIAM CANAZA-CAYO, UNAP, Peru; MARCOS VINICIUS GUALBERTO B SILVA, CNPGL; JAIME ARAUJO COBUCI, UFRGS; MARTA FONSECA MARTINS, CNPGL; PAULO SÁVIO LOPES, UFV.
Date Issued:	2016
Citation:	Genetics and Molecular Research, v. 15, n. 2, gmr.15027768, 2016.
Description:	The objective of this study was to evaluate the effects of inclusion or non-inclusion of short lactations and cow (CGG) and/or dam (DGG) genetic group on the genetic evaluation of 305-day milk yield (MY305), age at first calving (AFC), and first calving interval (FCI) of Girolando cows. Covariance components were estimated by the restricted maximum likelihood method in an animal model of single trait analyses. The heritability estimates for MY305, AFC, and FCI ranged from 0.23 to 0.29, 0.40 to 0.44, and 0.13 to 0.14, respectively, when short lactations were not included, and from 0.23 to 0.28, 0.39 to 0.43, and 0.13 to 0.14, respectively, when short lactations were included. The inclusion of short lactations caused little variation in the variance components and heritability estimates of traits, but their non-inclusion resulted in the re-ranking of animals. Models with CGG or DGG fixed effects had higher heritability estimates for all traits compared with models that consider these two effects simultaneously. We recommend using the model with fixed effects of CGG and inclusion of short lactations for the genetic evaluation of Girolando cattle.
NAL Thesaurus:	Girolando heritability
Keywords:	Genetic group Short lactation Variance components
DOI:	http://dx.doi.org/10.4238/gmr.15027768
Type of Material:	Artigo de periódico
Access:	openAccess
Appears in Collections:	Artigo em periódico indexado (CNPGL)