By P.M. VanRaden & G.R. Wiggans
Animal Improvement Programs Laboratory, ARS-USDA, Beltsville, MD
20705-2350
301-504-8334 (voice) ~ 301-504-8092 (fax) ~
rlaipl@aipl.arsusda.gov ~
http://aipl.arsusda.gov
The average of evaluations of cows born in 1995 are set to zero starting with the August 2000 evaluations. The variance base was not changed in order to minimize the differences between the August evaluations and the test run results that were provided to Interbull. See (The 'base' file from 2000 is no longer available.) for estimated changes in production traits and (The 'tbase' file from 2000 is no longer available.) for estimated changes in non-Holstein type traits.
Productive life evaluations for all cows and bulls are computed using multi-trait methods including evaluations for milk, fat, protein, productive life, somatic cell score, and three type composites. Previously, multi-trait productive life evaluations were calculated only for Holstein bulls. The use of correlated information from other traits improves the accuracy of productive life evaluations, particularly for younger animals. See http://aipl.arsusda.gov/reference/multi-pl.htm.
Net merit has been redefined to represent lifetime profit. Type composites for udder, feet and legs, and size have been added, and the economic weights adjusted. See http://aipl.arsusda.gov/reference/nmcalc.htm.
All protein lactation records were adjusted from a crude protein to a true protein basis using the formula: true protein = crude protein - .0019*milk See http://aipl.arsusda.gov/reference/trueprot.htm.
To support calculating net merit for bulls with Interbull evaluations, pedigree for these bulls and their dams was added to the pedigree file. This process detected some errors in the Interbull pedigree, and routine detection of inconsistancies has been implemented.
The editing system has been changed so that when a new ID is detected for an existing cow control number the pedigree and production information is evaluated to see if the new ID is really another ID for the same cow. See http://aipl.arsusda.gov/formats/ccn.html.