Year: 2004
Type: article
Abstract: In international evaluations, it has been repeatedly found and shown that the ranking of top bulls is quite sensitive to national genetic trends. When the national genetic trends are incorrect, biased evaluations are expected (Bonaiti et al., 1993). To detect inconsistencies, trend validation tests have been proposed, in particular for production traits (Boichard et al., 1995; Interbull, 2004). Interbull requires that national data must pass these tests before being included in an international evaluation. For production traits, the first test (Method I) compares the genetic trend based on the first lactation only with the one obtained using all lactations. The second one (Method II) verifies that the regression coefficient of daughter yield deviations (DYDs) defined within bull x year combinations on the year of use of the sire is not significantly different from 0. The third one (Method III) compares national proofs in successive evaluation runs.
Author: Vincent Ducrocq
Language: French
Subfield: Genetics
Domain: Life Sciences
SDG: Zero hunger
Open Access status: diamond
OpenAlex ID: W1488661996