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Registro completo
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Biblioteca (s) : |
INIA La Estanzuela; INIA Las Brujas. |
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Fecha : |
21/02/2014 |
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Actualizado : |
15/10/2019 |
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Tipo de producción científica : |
Artículos en Revistas Indexadas Internacionales |
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Autor : |
AGUILAR, I.; MISZTAL, I.; TSURUTA, S. |
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Afiliación : |
IGNACIO AGUILAR GARCIA, INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay; I. MISZTAL, University of Georgia (US); S. TSURUTA, University of Georgia (US). |
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Título : |
Genetic components of heat stress for dairy cattle with multiple lactations. |
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Fecha de publicación : |
2009 |
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Fuente / Imprenta : |
Journal of Dairy Science, 2009, v. 92, no. 11, p. 5702-5711. |
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ISSN : |
0022-0302 |
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DOI : |
10.3168/jds.2008-1928 |
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Idioma : |
Español
Inglés |
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Contenido : |
ABSTRACT.
Data included 585,119 test-day records for milk, fat, and protein yields from the first, second, and third parities of 38,608 Holsteins in Georgia. Daily temperature-humidity indexes (THI) were available from public weather stations. Models included a repeatability test-day model with a random regression on a function of THI and a test-day random regression model using linear splines with knots at 5, 50, 200, and 305 d in milk and a function of THI. Random effects were additive genetic and permanent environmental in the repeatability model and additive genetic, permanent environmental, and herd year in the random regression model. Additionally, models included fixed effects for herd test day, calving age, milking frequency, and lactation stage. Phenotypic variance increased by 50 to 60% from the first to second parity for all yield traits with the repeatability model and by 12 to 15% from the second to third parity. General additive genetic variance increased by 25 to 35% from the first to second parity for all yield traits but decreased slightly from the second to third parity for milk and protein yields. Genetic variance for heat tolerance doubled from the first to second parity and increased by 20 to 100% from the second to third parity. Genetic correlations among general additive effects were lowest between the first and second parities (0.84 to 0.88) and were highest between the second and third parities (0.96 to 0.98). Genetic correlations among parities for the effect of heat tolerance ranged from 0.56 to 0.79. Genetic correlations between general and heat-tolerance effects across parities and yield traits ranged from -0.30 to -0.50. With the random regression model, genetic variance for heat tolerance for milk yield was approximately one-half that of the repeatability model. For milk yield, the most negative genetic correlation (approximately -0.45) between general and heat-tolerance effects was between 50 and 200 d in milk for the first parity and between 200 and 305 d in milk for the second and third parities. The genetic variance of heat tolerance increased substantially from the first to third parity. Genetic estimates of heat tolerance may be inflated with the repeatability model because of timing of lactations to avoid peak yield during hot seasons.
© American Dairy Science Association, 2009. MenosABSTRACT.
Data included 585,119 test-day records for milk, fat, and protein yields from the first, second, and third parities of 38,608 Holsteins in Georgia. Daily temperature-humidity indexes (THI) were available from public weather stations. Models included a repeatability test-day model with a random regression on a function of THI and a test-day random regression model using linear splines with knots at 5, 50, 200, and 305 d in milk and a function of THI. Random effects were additive genetic and permanent environmental in the repeatability model and additive genetic, permanent environmental, and herd year in the random regression model. Additionally, models included fixed effects for herd test day, calving age, milking frequency, and lactation stage. Phenotypic variance increased by 50 to 60% from the first to second parity for all yield traits with the repeatability model and by 12 to 15% from the second to third parity. General additive genetic variance increased by 25 to 35% from the first to second parity for all yield traits but decreased slightly from the second to third parity for milk and protein yields. Genetic variance for heat tolerance doubled from the first to second parity and increased by 20 to 100% from the second to third parity. Genetic correlations among general additive effects were lowest between the first and second parities (0.84 to 0.88) and were highest between the second and third parities (0.96 to 0.98). Genetic correlations among parities for... Presentar Todo |
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Thesagro : |
GANADO DE LECHE; LACTANCIA; MODELOS MATEMÁTICOS; PRODUCCION DE LECHE. |
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Asunto categoría : |
-- |
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URL : |
http://www.ainfo.inia.uy/digital/bitstream/item/3707/1/Aguilar-I.-2009.-Jr.Dairy-Sc.-v.92-p.5702-5711.pdf
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Marc : |
LEADER 02974naa a2200217 a 4500
001 1012833
005 2019-10-15
008 2009 bl uuuu u00u1 u #d
022 $a0022-0302
024 7 $a10.3168/jds.2008-1928$2DOI
100 1 $aAGUILAR, I.
245 $aGenetic components of heat stress for dairy cattle with multiple lactations.
260 $c2009
520 $aABSTRACT. Data included 585,119 test-day records for milk, fat, and protein yields from the first, second, and third parities of 38,608 Holsteins in Georgia. Daily temperature-humidity indexes (THI) were available from public weather stations. Models included a repeatability test-day model with a random regression on a function of THI and a test-day random regression model using linear splines with knots at 5, 50, 200, and 305 d in milk and a function of THI. Random effects were additive genetic and permanent environmental in the repeatability model and additive genetic, permanent environmental, and herd year in the random regression model. Additionally, models included fixed effects for herd test day, calving age, milking frequency, and lactation stage. Phenotypic variance increased by 50 to 60% from the first to second parity for all yield traits with the repeatability model and by 12 to 15% from the second to third parity. General additive genetic variance increased by 25 to 35% from the first to second parity for all yield traits but decreased slightly from the second to third parity for milk and protein yields. Genetic variance for heat tolerance doubled from the first to second parity and increased by 20 to 100% from the second to third parity. Genetic correlations among general additive effects were lowest between the first and second parities (0.84 to 0.88) and were highest between the second and third parities (0.96 to 0.98). Genetic correlations among parities for the effect of heat tolerance ranged from 0.56 to 0.79. Genetic correlations between general and heat-tolerance effects across parities and yield traits ranged from -0.30 to -0.50. With the random regression model, genetic variance for heat tolerance for milk yield was approximately one-half that of the repeatability model. For milk yield, the most negative genetic correlation (approximately -0.45) between general and heat-tolerance effects was between 50 and 200 d in milk for the first parity and between 200 and 305 d in milk for the second and third parities. The genetic variance of heat tolerance increased substantially from the first to third parity. Genetic estimates of heat tolerance may be inflated with the repeatability model because of timing of lactations to avoid peak yield during hot seasons. © American Dairy Science Association, 2009.
650 $aGANADO DE LECHE
650 $aLACTANCIA
650 $aMODELOS MATEMÁTICOS
650 $aPRODUCCION DE LECHE
700 1 $aMISZTAL, I.
700 1 $aTSURUTA, S.
773 $tJournal of Dairy Science, 2009$gv. 92, no. 11, p. 5702-5711.
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Registro original : |
INIA Las Brujas (LB) |
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| Registros recuperados : 2 | |
| 1. |  | RÍOS, A.; FONTAINA, R. La prevención de la resistencia en Uruguay. Anexo [Preventing resistance in Uruguay.] In: INIA (Instituto Nacional de Investigación Agropecuaria); Programa Nacional Producción y Sustentabilidad Ambiental. Uso de la biodiversidad para la evaluación del impacto de la intensificación agrícola y el diseño de agroecosistemas sustentables. Las Brujas, Canelones (Uruguay): INIA, 2012. p.112 (INIA Serie Actividades de Difusión; 674) Trabajo presentado en: Pan-American Weed Resistence Conference organizada por Bayer Crop Science , Miami, Florida. 19-21 de enero de 2010.| Biblioteca(s): INIA Las Brujas. |
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| Registros recuperados : 2 | |
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