Change of Milk Production with Housing System and Herd Expansion

Abstract Milk production per cow often declines following expansion of a dairy herd. In this study of 192 Minnesota herds, loss of production depended on the change in housing system and herd management during and immediately after expansion. Four housing switches were studied: 1) stanchion to tie stall, 2) loose housing to cold free stall, 3) stanchion to warm free stall, and 4) stanchion to cold free stall. Since year of new construction varied, data were adjusted to a base year with constants derived from control herds (70 stanchion and 70 loose housing herds). Deviations in production and income over feed cost following new construction then were related to yearly changes among control herds. Stanchion to tie stall herds produced 26 kg more 3.5% fat-corrected milk than control stanchion herds. Stanchion to warm or cold free stall herds produced nearly 200 kg less 3.5% fat-corrected milk than control stanchion herds. Yearly deviation in milk yield and income over feed cost did not vary significantly between changes of the four housing systems and control herds.