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Progeny Testing Methods in Europe ¹

Department of Dairy Science, University of Illinois, Urbana

ABSTRACT

The progress which can be made in the improvement of milk and butterf at yield in dairy-cows depends to a large extent on the selection of males. Robertson and Eendel (12) estimated that in a closed population of 2,000 cows with the optimum structure, 43% of the total improvement arises from the breeding of young bulls from tested sires and 33% from selection of the same bulls on their dams' yield. The selection of dams of cows would contribute only 6% to the progress. Since about 60% of all heifer calves are needed for herd replacement, and many other things than the milk yield of the dam are decisive for whether a heifer calf is raised, the efficiency of female selection will always be low.

In Denmark, progeny testing of dairy bulls started in 1902, based on records from the cow testing associations, and since 1912 these tests have been carried out as dam-daughter comparisons.

¹ Presented in a Symposium at the American Dairy Science Association's meeting at the University of Illinois, Urbana, June 17, 1959.

² Agricultural College, Uppsada, Sweden.