METHOD AND EFFECTS OF INCORPORATING FOREIGN INFORMATION INTO UNITED-KINGDOM PRODUCTION EVALUATIONS

Countries, which import a significant amount of semen, embryos and ani mals, are faced with the problem of how properly to evaluate the anima ls in the national evaluation system when information on the foreign p arents is generally missing. Additional problems arise when the foreig n parents obtain an evaluation, usually on the basis of progeny, in th e country of import with the result that there are two published evalu ations for the animals in question. This paper presents a post-iterati ve method of incorporating foreign information into home country evalu ations. The foreign information is initially converted to the same sca le and base as in the home country using procedures recommended by the International Bull Evaluation Service. The method consists essentiall y of calculating a combined evaluation for animals with home and forei gn information as a weighted average of yield deviations, parent avera ges and progeny contributions from the foreign and home countries. The combined evaluations are used to adjust the evaluations of progeny on the basis of formulae derived from the usual mixed model equations. T he same principles were used to combine reliabilities from the respect ive home and foreign reliabilities. The results from the application o f the method to the United Kingdom (UK) Holstein Friesian population a re presented. There was re-ranking of both bulls and cows, especially foreign bulls with few UK daughters.