| |
|
|
 | Acesso ao texto completo restrito à biblioteca da Embrapa Gado de Corte. Para informações adicionais entre em contato com biblioteca@embrapa.br. |
|
Registro Completo |
|
Biblioteca(s): |
Embrapa Gado de Corte. |
|
Data corrente: |
07/02/2013 |
|
Data da última atualização: |
07/02/2013 |
|
Tipo da produção científica: |
Artigo em Periódico Indexado |
|
Autoria: |
ALBERTINI, T. Z.; MEDEIROS, S. R. de; TORRES JUNIOR, R. A. de A.; ZOCHI, S. S.; OLTJEN, J. W.; STRATHE, A. B.; LANNA, D. P. D. |
|
Afiliação: |
T. Z. Albertini, USP/ESALQ; SERGIO RAPOSO DE MEDEIROS, CNPGC; ROBERTO AUGUSTO DE A TORRES JUNIOR, CNPGC; S. S. Zocchi, USP/ESALQ; J. W. Oltjen, UNIVERSITY OF CALIFORNIA; A. B. Strathe, UNIVERSITY OF CALIFORNIA; D. P. D. LANNA, USP/ESALQ. |
|
Título: |
A methodological approach to estimate the lactation curve and net energy and protein requirements of beef cows using nonlinear mixed-effects modeling. |
|
Ano de publicação: |
2012 |
|
Fonte/Imprenta: |
Journal of Animal Science, v.90, n.11, p.3867-3878, Nov. 2012. |
|
Idioma: |
Inglês |
|
Conteúdo: |
The objective of this study was to evaluate methods to predict the secretion of milk and net energy and protein requirements of beef cows (Bos indicus and B. taurus) after approximately 1 mo postpartum using nonlinear mixed-effect modeling (NLME). Twenty Caracu × Nellore (CN) and 10 Nellore (NL) cows were inseminated to Red Angus bulls, and 10 Angus × Nellore (AN) were bred to Canchim bulls. Cows were evaluated from just after calving (25 ± 11 d) to weaning (220 d). Milk yield was estimated by weighing calves before and after suckling (WSW) and by machine milking (MM) methods at 25, 52, 80, 109, 136, 164, 193, and 220 ± 11 d of lactation. Brody and simple linear equations were consecutively fi tted to the data and compared using information criteria. For the Brody equation, a NLME model was used to estimate all lactation profiles incorporating different sources of variation (calf sex and breed of cow, cow as a nested random effect, and within cow auto-correlation). The CV for the MM method (29%) was less than WSW (45%). Consequently, the WSW method was responsible for reducing the variance about 1.5 times among individuals, which minimized the ability to detect differences among cows. As a result, only milk yield MM data were used in the NLME models. The Brody equation provided the best fi t to this dataset, and inclusion of a continuous autoregressive process improved fi t (P < 0.01). Milk, energy and protein yield at the beginning of lactation were affected by cow genotype and calf sex (P < 0.001). The exponential decay of the lactation curves was affected only by genotype (P < 0.001). Angus × Nellore cows produced 15 and 48% more milk than CN and NL during the trial, respectively (P < 0.05). Caracu × Nellore cows produced 29% more milk than NL (P < 0.05). The net energy and net protein requirements for milk yield followed a similar ranking. Male calves stimulated their dams to produce 11.7, 11.4, and 11.9% more milk, energy and protein, respectively (P < 0.05). The MM method is better than the WSW technique to detect genetic or environmental differences in milk yield among beef cows. The data obtained by the MM method and analyzed by NLME models allows the inclusion of fi xed effects, random effects and an autoregressive process in lactation equations to describe lactation curves and net energy and protein requirements. The NLME is a powerful tool to describe differences in the secretion of milk due to heterosis and cell mammary external stimulus in beef cows. MenosThe objective of this study was to evaluate methods to predict the secretion of milk and net energy and protein requirements of beef cows (Bos indicus and B. taurus) after approximately 1 mo postpartum using nonlinear mixed-effect modeling (NLME). Twenty Caracu × Nellore (CN) and 10 Nellore (NL) cows were inseminated to Red Angus bulls, and 10 Angus × Nellore (AN) were bred to Canchim bulls. Cows were evaluated from just after calving (25 ± 11 d) to weaning (220 d). Milk yield was estimated by weighing calves before and after suckling (WSW) and by machine milking (MM) methods at 25, 52, 80, 109, 136, 164, 193, and 220 ± 11 d of lactation. Brody and simple linear equations were consecutively fi tted to the data and compared using information criteria. For the Brody equation, a NLME model was used to estimate all lactation profiles incorporating different sources of variation (calf sex and breed of cow, cow as a nested random effect, and within cow auto-correlation). The CV for the MM method (29%) was less than WSW (45%). Consequently, the WSW method was responsible for reducing the variance about 1.5 times among individuals, which minimized the ability to detect differences among cows. As a result, only milk yield MM data were used in the NLME models. The Brody equation provided the best fi t to this dataset, and inclusion of a continuous autoregressive process improved fi t (P < 0.01). Milk, energy and protein yield at the beginning of lactation were affected by cow genotype... Mostrar Tudo |
|
Palavras-Chave: |
Bovino de corte; Desempenho animal. |
|
Thesagro: |
Curva de Lactação; Nutrição Animal; Vaca. |
|
Categoria do assunto: |
-- |
|
Marc: |
LEADER 03344naa a2200253 a 4500
001 1948644
005 2013-02-07
008 2012 bl uuuu u00u1 u #d
100 1 $aALBERTINI, T. Z.
245 $aA methodological approach to estimate the lactation curve and net energy and protein requirements of beef cows using nonlinear mixed-effects modeling.$h[electronic resource]
260 $c2012
520 $aThe objective of this study was to evaluate methods to predict the secretion of milk and net energy and protein requirements of beef cows (Bos indicus and B. taurus) after approximately 1 mo postpartum using nonlinear mixed-effect modeling (NLME). Twenty Caracu × Nellore (CN) and 10 Nellore (NL) cows were inseminated to Red Angus bulls, and 10 Angus × Nellore (AN) were bred to Canchim bulls. Cows were evaluated from just after calving (25 ± 11 d) to weaning (220 d). Milk yield was estimated by weighing calves before and after suckling (WSW) and by machine milking (MM) methods at 25, 52, 80, 109, 136, 164, 193, and 220 ± 11 d of lactation. Brody and simple linear equations were consecutively fi tted to the data and compared using information criteria. For the Brody equation, a NLME model was used to estimate all lactation profiles incorporating different sources of variation (calf sex and breed of cow, cow as a nested random effect, and within cow auto-correlation). The CV for the MM method (29%) was less than WSW (45%). Consequently, the WSW method was responsible for reducing the variance about 1.5 times among individuals, which minimized the ability to detect differences among cows. As a result, only milk yield MM data were used in the NLME models. The Brody equation provided the best fi t to this dataset, and inclusion of a continuous autoregressive process improved fi t (P < 0.01). Milk, energy and protein yield at the beginning of lactation were affected by cow genotype and calf sex (P < 0.001). The exponential decay of the lactation curves was affected only by genotype (P < 0.001). Angus × Nellore cows produced 15 and 48% more milk than CN and NL during the trial, respectively (P < 0.05). Caracu × Nellore cows produced 29% more milk than NL (P < 0.05). The net energy and net protein requirements for milk yield followed a similar ranking. Male calves stimulated their dams to produce 11.7, 11.4, and 11.9% more milk, energy and protein, respectively (P < 0.05). The MM method is better than the WSW technique to detect genetic or environmental differences in milk yield among beef cows. The data obtained by the MM method and analyzed by NLME models allows the inclusion of fi xed effects, random effects and an autoregressive process in lactation equations to describe lactation curves and net energy and protein requirements. The NLME is a powerful tool to describe differences in the secretion of milk due to heterosis and cell mammary external stimulus in beef cows.
650 $aCurva de Lactação
650 $aNutrição Animal
650 $aVaca
653 $aBovino de corte
653 $aDesempenho animal
700 1 $aMEDEIROS, S. R. de
700 1 $aTORRES JUNIOR, R. A. de A.
700 1 $aZOCHI, S. S.
700 1 $aOLTJEN, J. W.
700 1 $aSTRATHE, A. B.
700 1 $aLANNA, D. P. D.
773 $tJournal of Animal Science$gv.90, n.11, p.3867-3878, Nov. 2012.
Download
Esconder MarcMostrar Marc Completo |
|
Registro original: |
Embrapa Gado de Corte (CNPGC) |
|
|
Biblioteca |
ID |
Origem |
Tipo/Formato |
Classificação |
Cutter |
Registro |
Volume |
Status |
URL |
Voltar
|
|
|
| Registros recuperados : 121 | |
| 4. |  | VILELA, N. J.; PIRES, A. M. M. Cenoura 'Brasília'. In: MAGALHÃES, M. C.; VEDOVOTO, G. L.; IRIAS, L. J. M.; VIEIRA, R. de C. M.; ÁVILA, A. F. D. (Ed.). Avaliação dos impactos da pesquisa da Embrapa: uma amostra de 12 tecnologias. Brasília, DF: Embrapa. Secretaria de Gestão e Estrategia, 2006. p. 181-197.| Tipo: Capítulo em Livro Técnico-Científico | Circulação/Nível: -- - -- |
| Biblioteca(s): Embrapa Hortaliças. |
|   |
| 9. | | PIRES, A. M. M.; MATTIAZZO, M. E.; BERTON, R. Àcidos orgânicos como extratores de metais pesados fitodisponíveis em solos tratados com lodo de esgoto. REUNIÃO BRASILEIRA DE FERTILIDADE DO SOLO E NUTRIÇÃO DE PLANTAS, 26.; REUNIÃO BRASILEIRA SOBRE MICORRIZAS, 10.; SIMPÓSIO BRASILEIRO DE MICROBIOLOGIA DO SOLO, 8.; REUNIÃO BRASILEIRA DE BIOLOGIA DO SOLO, 5., 2004, Lages. Avaliação das conquistas: bases para estratégias futuras [anais]. Lages: UDESC: SBCS, 2004. CD-ROM. Fs 09.| Biblioteca(s): Embrapa Hortaliças. |
| |
| 11. | | SOUZA, M. D. de; PIRES, A. M. M. Amostragem de solos para análise de nitratos. In: FILIZOLA, H. F.; GOMES, M. A. F.; SOUZA, M. D. de. Manual de procedimentos de coleta de amostras em áreas agrícolas para análise da qualidade ambiental: solo, água e sedimentos. Jaguariúna: Embrapa Meio Ambiente, 2006. p. 49-52.| Tipo: Capítulo em Livro Técnico-Científico |
| Biblioteca(s): Embrapa Meio Ambiente. |
|  |
| Registros recuperados : 121 | |
|
| Nenhum registro encontrado para a expressão de busca informada. |
|
|
