Genetic parameters for milk yield and lactation persistency in the three first parities of Iranian Holstein cows
نویسندگان
چکیده
منابع مشابه
Estimation of Genetic Parameters for Lactation Curve Traits in Holstein Dairy Cows in Iran
The objectives were to estimate (co)variance components and genetic parameters for lactation curve traits in Holstein dairy cows in Iran. The used data were records on Holstein cows collected during January 2003 to December 2012 by the Animal Breeding Center of Iran (Karaj, Iran). In order to describe the lactation curve, an incomplete gamma function was fitted to 691200 test-day records on 962...
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The aim of the present study was to estimate genetic and phenotypic parameters of milk production traits in the first and second lactations of Romanian Simmental dairy cattle. For the estimation of variance, heritability, genetic and phenotypic correlations among milk yield, fat yield, protein yield, and percentages of fat and protein, 3400 first and second lactation records over a period of fi...
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In this study, appropriate genetic co (variance) structure across ages of milk production in the Iranian Holstein cows was modeled using 35167 records originated from 1098 sires and 27236 dams. These data were collected from 110 herds during 2011 to 2015 by the Iranian Animal Breeding Center. For all lactations, birth year, birth month, calving year, calving season, calving month, age and herd ...
متن کاملGenetic Parameter Estimates for Lactation Curve Parameters, Milk Yield, Age at First Calving, Calving Interval and Somatic Cell Count in Holstein Cows
The objective of this study was to estimates the genetic and environmental components for the lactation curve parameters, milk yield, age at first calving (AFC), calving interval (CI) and somatic cell count (SCC) in Iranian Holstein cows. The dataset consisted of 210625 test day records from 25883 cows with milk yield in the first parity recorded from July 2002 to September 2007 in a total of 9...
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ژورنال
عنوان ژورنال: Revista Colombiana de Ciencias Pecuarias
سال: 2019
ISSN: 2256-2958,0120-0690
DOI: 10.17533/udea.rccp.v32n2a03