Contrasting Models for Lactation Curve Analysis [PDF]
Journal of Dairy Science, 2002 Several statistical models have been proposed for the genetic evaluation of production traits in dairy cattle based on test-day records. Three main approaches have been put forward in the literature: random regression, orthogonal polynomials, and, more recently, character process models.
Jaffrezic, Florence +3 more
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Lactation curve modelling using Legendre Polynomial in Sahiwal cattle [PDF]
Indian Journal of Animal Sciences, 2016 Present study aimed at modelling lactation curve in Sahiwal cattle using normalized Legendre polynomials functions of standardized units of time and understanding the variation of lactation curve in different lactations. Among the first three lactations,
VED PRAKASH +3 more
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Modelling Lactation Curve for Genetic Evaluation of Crossbred Cattle [PDF]
International Journal of Bio-Resource and Stress Management, 2023 The present study was conducted on first lactation 4415 monthly test-day milk yield records of 466 crossbred (CB) cattle sired by 89 bulls during 2000–2018 (19 years) maintained at Directorate of Livestock Farms, GADVASU, Ludhiana, Punjab, India.
Rohit Gupta +4 more
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Determination of the Best Lactation Curve Model and Lactation Curve Parameters using Different Nonlinear Models for Anatolian Buffaloes [PDF]
Pakistan Journal of Zoology, 2020 The present investigation was conducted to determine the lactation curve parameters and to choose the best model that defines the lactation curve. Data were composed of 4897 test day milk yield (TDMY) records from Anatolian buffaloes calved during 2014-2017 raised under different farm conditions in Amasya Province, Turkey.
Kul, Ertuğrul
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Genetic and Environmental Smoothing of Lactation Curves with Cubic Splines [PDF]
Journal of Dairy Science, 1999 Most approaches to modeling lactation curves involve parametric curves with fixed or random coefficients. In either case, the resulting models require the specification on an underlying parametric curve. The fitting of splines represents a semiparametric approach to the problem.
White, I. M. S. +2 more
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Genome-wide association for milk production and lactation curve parameters in Holstein dairy cows [PDF]
Journal of Animal Breeding and Genetics, 2020 Cinzia Marchitelli +2 more
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Characterization of the lactation curve of f1 Holstein-Zebu cows [PDF]
Ecosistemas y Recursos Agropecuarios, 2018 The objective was to nd a function to describe the lactation curve of grazing Holstein - Zebu cows (n=23) in tropical México. Twelve were based on the general nonlinear function A*Φ1(x)*Φ2(x): A, a positive scalar; Φ1 , a positive monotonically ...
Epigmenio Castillo-Gallegos
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On designing the average lactation curve at the ascending phase [PDF]
Agricultural and Food Science, 1962 Comparisons are made between different methods to find the peak production (maximum daily milk yield) and methods to design the average lactation curve at the ascending phase in dairy cows.
Aarne Mäkelä
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Investigating lactation curve characteristics of dairy cows
Науковий вісник Львівського національного університету ветеринарної медицини та біотехнологій імені С.З. Гжицького. Серія: Сільськогосподарські науки, 2023 The main goal of this study was to analysis of the main characteristics (latent variables) of lactation curve in dairy cows using multivariate Principal Component Analysis.
O. S. Kramarenko
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Comparison of Mathematical Models Applied to F1 Dairy Sheep Lactations in Organic Farm and Environmental Factors Affecting Lactation Curve Parameter [PDF]
Asian-Australasian Journal of Animal Sciences, 2013 The objective of this study was to compare the goodness of fit of four lactation curve models: Wood’s Gamma model (WD), Wilmink (WL), and Pollott’s multiplicative two (POL2) and three parameters (POL3) and to determine the environmental factors affecting
J. C. Angeles-Hernandez +4 more
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