|EAGLEN, SOPHIE - National Association Of Animal Breeders|
|LAWLOR, JR., THOMAS - Holstein Association Usa, Inc|
|NICOLAZZI, EZEQUIEL - Council On Dairy Cattle Breeding|
Submitted to: Progressive Dairyman
Publication Type: Trade Journal
Publication Acceptance Date: 6/3/2020
Publication Date: N/A
Technical Abstract: The phenotypic base used for expressing calving traits evaluations will be updated in August 2020. The average PTA for all traits will decrease by 1 to 6 points. Holstein predicted transmitting abilities will average 2.2 and 2.7 for sire and daughter calving ease, which means that selection thresholds such as “no bull over 8” are no longer necessary. The bases for Brown Swiss calving ease and Holstein stillbirth will also decrease. The stillbirth traits will now be expressed in terms of percent stillbirths in heifers to match the calving ease traits. Dairy farmers have successfully reduced the rates of dystocia and stillbirth, which is why the bases need to be changed, but it will remain important to select the best available bulls for breeding to your heifers.