الفهرس 
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Abstract
The objectives of the present study were: 1) to estimate some genetic and non-genetic factors affecting productive and reproductive traits, 2) to obtain heritability estimates for each of milk production and reproductive traits of the study in addition the coefficients of genetic and phenotypic correlation coefficient among all traits of the study once when using data of all available lactations produced and 3) to estimate breeding values for sire and dam Friesian cows in this farm.
The main results obtained can be summarized as follows:
The overall means of lactation milk yield, 305-DMY and LL in this study averaged2868.5kg, 2912.7kg and 306.15days, respectively.Animal origin constituted a significant source of variation in lactation milk yield and 305-days milk yield, While did not have any significant effect on lactation length and dry period. Season of calving had no significant effect on LMY while it has significant effect on the 305-DMY, LL and DP.
Parity effect was found to be significant on LMY, 305-day milk yield and length of lactation period, while it does not have a significant effect on the dry period.When using data of all available lactations year of calving showed significant effects on lactation milk yield, 305-day milk yield, lactation length and dry period. For reproductive traits animal origin has not had any significant effect on the lactation milk yield or length of productive life (P>0.05), results shows that there is a highly significant effect (P<0.01) of animal origin on calving interval and the age at first calving.