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Abstract
The purposes of this study were to :investigate non-genetic factors affecting 60 day milk yield(60 day MY), 305 day milk yield(305 d MY),loctation period (LP),days open(DO), and age at first calving (AFC).2-estimate phenotypic and genetic parameters for these traits.3- constructed selection indexes combining four first loctation economic traits in different combinations for Holstein friesian cattle in Egypt,based upon net profit from milk.