|Miller, R -|
Submitted to: World Congress of Genetics Applied in Livestock Production
Publication Type: Abstract Only
Publication Acceptance Date: June 1, 2010
Publication Date: August 1, 2010
Citation: Norman, H.D., Wright, J.R., Miller, R.H. 2010. Potential Consequences Of Selection On Gestation Length On Holstein Performance. World Congress of Genetics Applied in Livestock Production. Proc. 9th World Congr. Genet. Appl. Livest. Prod., Leipzig, Germany, Aug. 1–6, abstr. p. 23. Technical Abstract: Genetic evaluations of Holstein gestation length (GL) were analyzed to determine their reliability and repeatability. Potential consequences of selection on GL were assessed by examining impact on performance in the subsequent lactation. Service-sire predicted transmitting ability (PTA) for GL was effective in identifying bulls that could be expected to modify GL. Intermediate service-sire PTA GL was optimal for yield traits and days open; performance for productive life, calving ease, stillbirth and culling generally became less favorable as service-sire PTA GL increased. Based on phenotypic cow GL, performance generally improved for subsequent lactation yield as GL increased; intermediate GL was optimal for productive life, calving ease, stillbirth, culling and days open. Changing Holstein GL by more than a day or two would have limited benefit for overall performance.