Dynamics of culling risk with disposal codes reported by Dairy Herd Improvement dairy herds.

摘要: The objective was to describe the dynamics of culling risk with disposal codes for Holstein dairy cows reported by herds enrolled in Dairy Herd Improvement program. producers could report 1 9 possible or forego reporting a code. After edits, 3,629,002 lactation records were available calving between 2001 and 2006 2,054 located 38 states primarily east Mississippi river. distribution culled code estimated parity, days after calving, pregnancy status, cow-relative 305-d mature equivalent milk yield, herd-relative season. Of all herds, 57% 8 different excluding purposes reason not reported. Hazard (risk) functions calculated from 520 d since open 280 conception pregnant cows. Annualized live rate death (reported death) 25.1 6.6%, respectively. primary died (20.6% culling), followed reproduction (17.7%), injury/other (14.3%), low production mastitis (both 12.1%). various varied stage lactation. Died most frequently leaving herd during early late lactation, Early also critical period disease, increased reproduction. showed greatest seasonal pattern spring summer. A negative association found annualized rates within herds. Compared cows, had lower codes. In addition, high-producing conclusion, season, yield.