Data were USDA genetic evaluations of cows and DHI herd profiles from 4154
Holstein progeny-test herds from two artificial insemination organizations,
21st Century Genetics (Shawano, WI) and Genex (Ithaca, NY), and from 6361
additional herds from Minnesota and New York. We grouped herds into four ca
tegories: 21st Century Genetics herds, other Minnesota herds, Genex herds,
and other New York herds. Herds were eliminated if they contributed fewer t
han 10 cows with genetic evaluations and birth dates from January 1989 to M
arch 1995. Data included 83 and 74%, respectively, of first-crop daughters
of 21st Century Genetics and Genex progeny-test bulls with genetic evaluati
ons from January 1995 to February 1997. Herds were characterized by DHI pro
file and cow evaluation data. Daughters of progeny-test bulls with extreme
production records (outside of 3 SD) relative to herd mean and variance did
not appear in disproportionate numbers among the progeny of bulls likely c
ulled or considered for further use. The two organizations appear to have s
elected larger, genetically superior, and better managed herds from within
their respective regions for progeny-testing purposes. We were not able to
predict whether a bull in the progeny-testing programs of these two organiz
ations was going to exceed or fail to meet the pedigree prediction from cha
racteristics of herds in which his daughters performed. Differences between
parent average and daughter yield deviations for typical young sires appea
r to result from Mendelian segregation of genes.