Evaluation of Different Measures of Milk Yield Persistency in Iranian Holstein Dairy Cows
نویسندگان
چکیده
منابع مشابه
Analysis of Test Day Milk Yield by Random Regression Models and Evaluation of Persistency in Iranian Dairy Cows
Variace / covariance components of 227118 first lactaiom test-day milk yield records belonged to 31258 Iranian Holstein cows were estimated using nine random regression models. Afterwards, different measures of persistency based on estimation breeding value were evaluated. Three functions were used to adjust fixed lactation curve: Ali and Schaeffer (AS), quadratic (LE3) and cubic (LE4) order of...
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ژورنال
عنوان ژورنال: Journal of Agricultural Studies
سال: 2016
ISSN: 2166-0379
DOI: 10.5296/jas.v4i3.9608