Voluntary Waiting Period Management Practices in Dairy Herds Participating in a Progeny Test Program

Autor: C.E. Marshall, J.M. DeJarnette, C.G. Sattler, R.L. Nebel
Rok vydání: 2007
Předmět:
Zdroj: Journal of Dairy Science. 90:1073-1079
ISSN: 0022-0302
DOI: 10.3168/jds.s0022-0302(07)71594-1
Popis: A survey was mailed to approximately 4,000 herds participating in a young sire progeny test program to estimate the percentage of herds that selectively alter the voluntary waiting period (VWP) for individual cows or groups of cows. Responses were received from 673 herds (17%; 583 Holsteins, 55 Jerseys, 35 other dairy breeds). The mean VWP cited by respondents was 56 +/- 0.6 d (range = 30 to 90 d) and did not differ by breed. Among responding herds, 64% (432/673) indicated the VWP was selectively altered for one or more reasons. The most frequently cited reasons for altering the VWP were postpartum health (50%), season (18%), milk yield (18%), parity (14%), and other reasons (14%). In Holstein herds that altered the VWP based on milk yield, the highest production group averaged 14 more days to first service than the lowest production group (> or =40 vs.
Databáze: OpenAIRE