الفهرس 
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Abstract
This study conducted to evaluate some of non-genetic and genetic parameters that affect the productive and reproductive traits. Total of 3596 records of 1021 Holstein Friesian cows in the first five parities were collected during the period from 2002 to 2016 from a commercial farm. Data of productive and reproductive traits were analyzed using general linear model procedure (SAS). In the present study the total milk yield (TMY, kg), dry period (DP, day), days open (DO, day), calving interval (CI, day), number of service per conception (NSC) and age at first calving (AFC, months) as well as total lifetime milk yield (TMYL, kg), total lactation length (TLL, day), productive live (PL, day), days of live until the end of 5th lactation (LIFE, day), milk per day of lactation length (MPDLL, kg), milk per day of productive life(MPDPL, kg), milk per day of life (MPDLIV, day) and number of lactation completed (NLC). Heritability estimates for TMY, LP, DP, DO, CI, NSC and AFC are 0.110, 0.089, 0.071, 0.100, 0.103, 0.123 and 0.168, respectively. The results showed that the heritability for longevity and lifetime traits were moderate, all coefficients were positive for genetic correlations for productive and reproductive traits and ranged from 0.031 to 0.988. Aim of the work : The main objective of this work to evaluate some of non-genetic and genetic parameters that affect the productive, reproductive and lifetime traits. Conclusion: The results are important to select the environmental condition and the positive traits relations to improve the productive and reproductive performance traits of the cows in the commercial herd.