Genetic and phenotypic parameters of productivity traits on the first three lactations in Gyr cattle herds
Autor(a) principal: | |
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Data de Publicação: | 1999 |
Outros Autores: | , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Genetics and Molecular Biology |
Texto Completo: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571999000200007 |
Resumo: | Records of Gyr cows selected for milk production were obtained from the National Gyr Dairy Cattle Breeding Program (Embrapa/CNPGL) and analyzed, in order to estimate genetic parameters for the first three lactations and to verify the effects of some environmental factors on milk production from 1979 to 1994. Genetic parameters were estimated by REML with an animal model and a group of fixed effects that included classes of herd, year, season and age at calving. Milk production means and standard deviations were 2,183 kg, 707 kg; 2,682 kg, 762 kg and 2,638 kg, 851 kg, for first, second, and third lactations, respectively. Heritability estimates were 0.20, 0.12, and 0.19 for first, second, and third lactations, respectively, and repeatability was 0.44. Genetic correlation estimates were: 0.68 between first and second lactations, 0.84 between first and third lactations and 1.0 between second and third lactations. Results confirm other research for specialized dairy breeds and firmly suggest that even in breeds of Indian origin the best time to make selection decisions is during the first lactation. |
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Genetics and Molecular Biology |
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Genetic and phenotypic parameters of productivity traits on the first three lactations in Gyr cattle herdsRecords of Gyr cows selected for milk production were obtained from the National Gyr Dairy Cattle Breeding Program (Embrapa/CNPGL) and analyzed, in order to estimate genetic parameters for the first three lactations and to verify the effects of some environmental factors on milk production from 1979 to 1994. Genetic parameters were estimated by REML with an animal model and a group of fixed effects that included classes of herd, year, season and age at calving. Milk production means and standard deviations were 2,183 kg, 707 kg; 2,682 kg, 762 kg and 2,638 kg, 851 kg, for first, second, and third lactations, respectively. Heritability estimates were 0.20, 0.12, and 0.19 for first, second, and third lactations, respectively, and repeatability was 0.44. Genetic correlation estimates were: 0.68 between first and second lactations, 0.84 between first and third lactations and 1.0 between second and third lactations. Results confirm other research for specialized dairy breeds and firmly suggest that even in breeds of Indian origin the best time to make selection decisions is during the first lactation.Sociedade Brasileira de Genética1999-06-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571999000200007Genetics and Molecular Biology v.22 n.2 1999reponame:Genetics and Molecular Biologyinstname:Sociedade Brasileira de Genética (SBG)instacron:SBG10.1590/S1415-47571999000200007info:eu-repo/semantics/openAccessAlbuquerque,Maria do Socorro MauésFreitas,Maria Armênia Ramalho deTeodoro,Roberto Luizeng1999-08-26T00:00:00Zoai:scielo:S1415-47571999000200007Revistahttp://www.gmb.org.br/ONGhttps://old.scielo.br/oai/scielo-oai.php||editor@gmb.org.br1678-46851415-4757opendoar:1999-08-26T00:00Genetics and Molecular Biology - Sociedade Brasileira de Genética (SBG)false |
dc.title.none.fl_str_mv |
Genetic and phenotypic parameters of productivity traits on the first three lactations in Gyr cattle herds |
title |
Genetic and phenotypic parameters of productivity traits on the first three lactations in Gyr cattle herds |
spellingShingle |
Genetic and phenotypic parameters of productivity traits on the first three lactations in Gyr cattle herds Albuquerque,Maria do Socorro Maués |
title_short |
Genetic and phenotypic parameters of productivity traits on the first three lactations in Gyr cattle herds |
title_full |
Genetic and phenotypic parameters of productivity traits on the first three lactations in Gyr cattle herds |
title_fullStr |
Genetic and phenotypic parameters of productivity traits on the first three lactations in Gyr cattle herds |
title_full_unstemmed |
Genetic and phenotypic parameters of productivity traits on the first three lactations in Gyr cattle herds |
title_sort |
Genetic and phenotypic parameters of productivity traits on the first three lactations in Gyr cattle herds |
author |
Albuquerque,Maria do Socorro Maués |
author_facet |
Albuquerque,Maria do Socorro Maués Freitas,Maria Armênia Ramalho de Teodoro,Roberto Luiz |
author_role |
author |
author2 |
Freitas,Maria Armênia Ramalho de Teodoro,Roberto Luiz |
author2_role |
author author |
dc.contributor.author.fl_str_mv |
Albuquerque,Maria do Socorro Maués Freitas,Maria Armênia Ramalho de Teodoro,Roberto Luiz |
description |
Records of Gyr cows selected for milk production were obtained from the National Gyr Dairy Cattle Breeding Program (Embrapa/CNPGL) and analyzed, in order to estimate genetic parameters for the first three lactations and to verify the effects of some environmental factors on milk production from 1979 to 1994. Genetic parameters were estimated by REML with an animal model and a group of fixed effects that included classes of herd, year, season and age at calving. Milk production means and standard deviations were 2,183 kg, 707 kg; 2,682 kg, 762 kg and 2,638 kg, 851 kg, for first, second, and third lactations, respectively. Heritability estimates were 0.20, 0.12, and 0.19 for first, second, and third lactations, respectively, and repeatability was 0.44. Genetic correlation estimates were: 0.68 between first and second lactations, 0.84 between first and third lactations and 1.0 between second and third lactations. Results confirm other research for specialized dairy breeds and firmly suggest that even in breeds of Indian origin the best time to make selection decisions is during the first lactation. |
publishDate |
1999 |
dc.date.none.fl_str_mv |
1999-06-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571999000200007 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571999000200007 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1590/S1415-47571999000200007 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
text/html |
dc.publisher.none.fl_str_mv |
Sociedade Brasileira de Genética |
publisher.none.fl_str_mv |
Sociedade Brasileira de Genética |
dc.source.none.fl_str_mv |
Genetics and Molecular Biology v.22 n.2 1999 reponame:Genetics and Molecular Biology instname:Sociedade Brasileira de Genética (SBG) instacron:SBG |
instname_str |
Sociedade Brasileira de Genética (SBG) |
instacron_str |
SBG |
institution |
SBG |
reponame_str |
Genetics and Molecular Biology |
collection |
Genetics and Molecular Biology |
repository.name.fl_str_mv |
Genetics and Molecular Biology - Sociedade Brasileira de Genética (SBG) |
repository.mail.fl_str_mv |
||editor@gmb.org.br |
_version_ |
1752122377345433600 |