Changes to evaluation system (January 2008)

New evaluation schedule

By Paul VanRaden, George Wiggans, and Leigh Walton

Three evaluation release dates of January 15, April 1, and August 19 are scheduled for 2008 to match the new Interbull (Uppsala, Sweden) schedule. Release was switched from Monday to Tuesday to avoid potential conflicts with holidays around the world. For the January evaluation, USDA calculations were done twice: U.S. data received by November 30 contributed to evaluation files sent to Interbull for its December 11 deadline, and data received by January 4 were included in new national evaluations to be released on January 15 for U.S. cows and for bulls with only U.S. daughters. Rules for determining officiality remain the same. Multitrait across-country evaluations calculated by Interbull for bulls with U.S. and foreign daughters will be official even if the number of U.S. daughters in January exceeds the international total from December. All traits except conformation, calving ease, and stillbirth are being reprocessed by USDA in January.

Although Interbull evaluations provide a convenient summary of bulls available worldwide, they may not contain the latest information because national and international calculations have differing schedules and release dates. For example, the joint Nordic evaluation has release dates of December 1 and January 15. On the same day that other countries release Interbull evaluations with December 1 data for Danish, Finnish, and Swedish bulls, new evaluations for those bulls will be available with 1.5 months more data. Similarly, when other countries publish Interbull evaluations for U.S. bulls, new national evaluations with 1 month more data will be available from USDA. Many breeders will look at the new 100-daughter evaluation on a foreign web site instead of the previous 90-daughter Interbull evaluation converted to their own country's scale. Several other major countries may also decide to recompute evaluations in early January; as a result, Interbull evaluations could be out of date on the day that they are released.

Interbull fertility evaluations for breeds other than Holstein

By Paul VanRaden, George Wiggans, and Mel Tooker

Multitrait Interbull evaluations for female fertility were extended to breeds other than Holstein, which had fertility evaluations introduced in February 2007. Most major populations are included, and genetic correlations across countries are similar to those reported earlier for Holsteins.

Interbull evaluations on Milking Shorthorn base

By George Wiggans

Evaluations of foreign bulls from Interbull on the Red Dairy Cattle (RDC) base will be converted to the Milking Shorthorn (MS) base if the bull has an MS identification (ID) number. The MS ID is not required to be the preferred ID. The American Milking Shorthorn Society can assign U.S. ID numbers to RDC foreign bulls to control which foreign bulls are reported on the MS base. Because the all-breed evaluation initially evaluates all animals on the same base, adjustments are available to convert RDC evaluations to the MS base appropriately. Evaluations of domestic MS bulls were sent to Interbull on the RDC base for all traits except conformation but were not included in Interbull evaluations because of a coding problem. The codes will be corrected for the May Interbull test evaluation so that other countries, particularly Australia, will receive Interbull evaluations of U.S. MS bulls beginning in August 2008.

Jersey, Brown Swiss, and Guernsey conformation composites

By Paul VanRaden and Jan Wright

Linear type composites used in the net merit index and in multitrait productive life evaluations were updated to match current breed association definitions for Jerseys, Guernseys, and Brown Swiss. The new formulas are described in AIPL Research Report NM$3 ("Net Merit as a Measure of Lifetime Profit: 2006 Revision").