In tropical countries, it is common to import semen from dairy taurine cattle breeds based on the genetic evaluations carried out in the countries of origin. Therefore, the objective of this study is to verify if the selection of sires based on the DPR (daughter pregnancy rate) estimated in the US genetic evaluation implies on the reduction of the days open of their daughters in Brazil. Data were collected from 325 daughters of 42 Holstein bulls stratified by DPR (DPR < -2, DPR > -2 and < 0, DPR > 0 and < 2, Group DPR > 2). The DPR data was collected from the 2018 US genetic evaluation of Holstein cattle. Each sire had in the database at least 4 daughters of reproductive age, raised in Freestall system and submitted to fixed-time artificial insemination. All the daughters evaluated were from the same farm. To compare the number of days open of each DPR group, a Tukey test with a 0.05 level of significance was performed. The results are shown in Table 1. The results demonstrated the selection of sires based on DPRs estimated in the US genetic evaluation impacts positively Brazilian herds, reducing cows days open.
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