Estimating Holstein Lactation Curves with a Gamma Curve
نویسندگان
چکیده
منابع مشابه
Comparison of Different Lactation Curve Models to Describe Lactation Curve in Moroccan Holstein-Friesian Dairy Cows
In this study, the incomplete gamma function, an exponential function, a mixed-log function and a polynomial function were evaluated to describe the lactation curve in Moroccan Holstein-Friesian dairy cows. Data from 1990 to 1999, comprising 77130 monthly milk yields of 6029 dairy cows in 280 dairy herds, were used. Edits were carried out by considering the lactation length (5 d and
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The effects of genes are commonly estimated using random regression models based on test-day data and only give a general gene effect. Alternatively, lactation curve models can be used to estimate biological and environmental effects, or to predict missing test-day data and perform breeding value estimation. This study combines lactation curve models and estimation of gene effects to represent ...
متن کاملcomparison of different lactation curve models to describe lactation curve in moroccan holstein-friesian dairy cows
in this study, the incomplete gamma function, an exponential function, a mixed-log function and a polynomial function were evaluated to describe the lactation curve in moroccan holstein-friesian dairy cows. data from 1990 to 1999, comprising 77130 monthly milk yields of 6029 dairy cows in 280 dairy herds, were used. edits were carried out by considering the lactation length (5 d and
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ژورنال
عنوان ژورنال: Journal of Dairy Science
سال: 1977
ISSN: 0022-0302
DOI: 10.3168/jds.s0022-0302(77)84028-9