Persistency Of Lactation
Mostrando 1-12 de 12 artigos, teses e dissertações.
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1. Association between gestation length and lactation performance, lactation curve, calf birth weight and dystocia in Holstein dairy cows in Iran
Abstract In this study, 252,798 lactations on 108,077 cows in 433 herds were used to determine the association between gestation length (GL) and lactation performance, lactation curve, calf birth weight and dystocia in Holstein dairy cows in Iran. The GL averaged 278.1 ± 5.41 d, was categorized as short (SGL; at 1 SD below the population mean), average (AGL
Anim. Reprod.. Publicado em: 25/11/2019
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2. Milk production in Saanen goats treated with repeated low doses of intermediate-release insulin during early lactation
RESUMO: O objetivo do estudo foi avaliar o efeito da administração de insulina sobre a resposta produtiva de cabras Saanen durante a lactação inicial. Dez de vinte fêmeas adultas foram sujeitas à administração subcutânea de repetidas e baixas doses de insulina de liberação intermediária aos 2, 9 e 14 dias pós-parto. A produção de leite foi me
Cienc. Rural. Publicado em: 04/04/2019
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3. Environmental and genetic effects on the lactation curves of four genetic groups of crossbred Holstein-Zebu cows
The objective of this study was to evaluate the effects of genetic group and environmental factors, including farm of origin, season of calving and lactation number, on the individual lactation curves of 1,010 Holstein-Gyr, Guzerat-Holstein, Holstein-Nellore, and Holstein-Zebu F1 cows on the experimental farms of the Agricultural Research Company in Minas Ge
R. Bras. Zootec.. Publicado em: 2012-11
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4. Persistency of lactation using random regression models and different fixed regression modeling approaches
Milk yield test-day records on the first three lactations of 25,500 Holstein cows were used to estimate genetic parameters and predict breeding values for nine measures of persistency and 305-d milk yield in a random regression animal model using two criteria to define the fixed regression. Legendre polynomials of fourth and fifth orders were used to model t
R. Bras. Zootec.. Publicado em: 2012-09
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5. Genetic avaluacion for persistency of lactation in Holstein cows using a random regression model
A model for analyzing test day records including both fixed and random coefficients was applied to the genetic evaluation of first lactation data for Holstein cows. Data comprising 87045 test-day milk yield records from calving between 1997 and 2001 from Holstein herds in 10 regions of the Brazilian state of Minas Gerais. Six persistency of lactation measure
Publicado em: 2010
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6. Persistência na lactação para vacas da raça Holandesa criadas no Estado do Rio Grande do Sul via modelos de regressão aleatória / Lactation persistency for Holstein cows raised in the State of Rio Grande do Sul using a random regression model
Foram utilizados 21.702 registros de produção de leite no dia do controle de 2.429 vacas primíparas da raça Holandesa, filhas de 233 touros, coletados em 33 rebanhos do Estado do Rio Grande do Sul, entre 1992 e 2003, para estimar parâmetros genéticos, para três medidas de persistência (PS1, PS2 e PS3) e para a produção de leite até 305 dias (P305)
Publicado em: 2010
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7. Medidas de persistência da produção de leite em rebanhos Gir Leiteiro utilizando modelos de regressão aleatória / Persistency of milk yield measures in Gyr herds using random regression models
Data comprising 27,000 test-day milk yield (TDMY) records of 3,362 first lactations of Gyr cows calving between 1990 and 2007 were used to compare random regression models for biweekly TDMY and to evaluate persistency of lactation milk yield (PS) measures. Records were analyzed by random regression models (RRM). Random trajectories were fitted by Wilminks (W
Publicado em: 2009
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8. Genetic evaluation of dairy buffaloes using random regression model / Avaliação genética em bubalinos leiteiros utilizando modelo de regressão aleatória
Com objetivo de avaliar seis medidas de persistência da produção de leite e o progresso genético em bubalinos leiteiros a partir das tendências genéticas da produção acumulada até 301 dias e da persistência da produção de leite em primeiras lactações de búfalas da raça Murrah, utilizaram-se 9.219 registros de produção de leite no dia do con
Publicado em: 2009
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9. Avaliação da produção de leite em cabras da raça Saanen utilizando modelos de regressão aleatória / Saanen goats milk yield evaluation using random regression models
Data from 10,238 weekly milk yield records from 388 first lactations of Saanen goats were used to evaluate the persistency of lactation under a random regression model. First, five models were compared (W035, W05, W0565, W068 e W10) generated by modifications of Wilmink function, assuming homogeneity of residual variance along the lactation. The value -0.05
Publicado em: 2008
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10. Genetic evaluation for persistency of lactation in Holstein cows using a random regression model
A model for analyzing test day records including both fixed and random coefficients was applied to the genetic evaluation of first lactation data for Holstein cows. Data comprising 87045 test-day milk yield records from calving between 1997 and 2001 from Holstein herds in 10 regions of the Brazilian state of Minas Gerais. Six persistency of lactation measure
Genetics and Molecular Biology. Publicado em: 2007-03
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11. ESTUDO DA PERSISTÊNCIA E PRODUÇÃO DE LEITE DE VACAS DA RAÇA HOLANDESA UTILIZANDO MODELO DE REGRESSÃO ALEATÓRIA / STUDY OF THE PERSISTENCE OF THE LACTATION IN HOLSTEIN COWS USING A RANDOM REGRESSION MODEL
A total of 21,702 test day milk yield records had been used of 2.429 first parity Holstein cows from 1991 and 2003, distributed in 33 herds of the state of Rio Grande do Sul, with the objective to estimate genetic parameters for persistence of lactation and milk production in the day of the control, to evaluate the relative efficiency of the selection for pe
Publicado em: 2006
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12. Variance components and breeding value for test day and lactation milk yields in holstein cattle with different statistical models. / Componentes de variância e valores genéticos para as produções de leite do dia do controle e da lactação na raça holandesa com diferentes modelos estatísticos.
Covariance components and genetic parameters for milk yield from 263,390 test-day records of 32,448 first lactation Holstein cows were estimated using animal models by REML. Test-day repeatability (RM) and random regression (RR) models were compared to a 305-d lactation model (P305) to estimate breeding values. Random regression involved the five-parameter l
Publicado em: 2003