In this paper we tried to estimate gene effects of three bulls that are mated with five populations of half-sisters by sire line for milk amount. We wanted to fortify whether the order of bull.s gene effects was unchangeable or it was modified. Totally we analyzed 2824 lactation. Investigation was made on two different generations of Holstein cows (mothers and daughters). Analysis of results for milk production of mothers showed that between different populations of mothers exist significant differences (P<0.05 and P<0.01).
It was fortified that order of bulls wasn.t same i.e. that their breeding value (like sum of all present genes in one individual) was various on the different populations of cows
