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Breeding Practices on Illinois Holstein Farms

1983; Elsevier BV; Volume: 66; Issue: 5 Linguagem: Inglês

10.3168/jds.s0022-0302(83)81921-3

1529-9066

R.D. Shanks, Kathleen A Rooney, Michael F. Hutjens,

Effects of Environmental Stressors on Livestock

Questionnaires requesting breeding information were mailed to 1,148 Illinois Holstein herds in the Dairy Herd Improvement program.A total of 591 questionnaires (51%) were returned.Dairy producers with herds producing over 7,100 kg of milk returned 64% of their questionnaires whereas 34% of dairy producers with herds producing less than 5,900 kg returned their questionnaires.State average and standard errors were: 23 + 1 bulls used per 100 cows, 78 -+ 2% dairy producers select the bulls, 96 -+ 1% herds use artificial insemination, 2.1 + .1 artificial insemination organizations per herd, 29 -+ 2% herds participate in young sire testing programs, 87 + 1% farmers consider calving ease indicators in mating heifers, and 17 -+ 2% farmers consider calving ease indicatoi's in mating cows.Breeding practices positively associated with increasing rolling herd average milk production were number of bulls per herd and per 100 cows, self as bull selector, use of artificial insemination, number of artificial insemination organizations, and participation in young sire testing programs.Three breeding practices were negatively associated with increasing rolling herd average milk production: artificial-insemination technician as bull selector and consideration of calving ease for mating heifers and cows.Dairy producers also were asked to rate the emphasis placed on traits in bull and cow selection.For bull selection, udder conformation and Predicted Difference milk were most important.In cow selection, milk production, followed by udder conformation, feet and legs, and