What Level of Milk Production Is Best For Drying Off Or Culling A Dairy Cow?

Dairy Pipeline: July 2008

John Currin, Extension Dairy Veterinarian
(540) 231-5838; jcurrin@vt.edu

With all the increases in feed cost, it is time to reevaluate the proper level of milk production at which to dry off or sell a cull cow. The two most important factors to consider when making this decision are feed costs and milk price. Other contributing factors are forage availability and overcrowding. If you are short on forage then it may be more beneficial to dry off or sell cows earlier than the breakeven milk production to avoid running out of feed. If the dairy is overcrowded, the extra cows may affect the milk production of the entire herd and thus they should leave the lactating string earlier than their breakeven point. The easiest way to determine if overcrowding is an issue on your farm is to dry off and/or sell 5-10% of your cows at about the same time. Then, observe what happens to the bulk tank milk weights. If the bulk tank weights stay about the same or even increases a little you will know that overcrowding was affecting milk production. Table 1 shows the breakeven milk production levels to dry a cow off for several different levels of milk and feed prices.

Table 2 shows the breakeven level of milk production to cull a cow. Several assumptions have been made to model the breakeven point. The first assumption is that a cow at this level of milk production will eat approximately 85% of the herd average dry matter intake. The second assumption is that feed costs make up 90% of the variable cost of milk production for these cows. As mentioned before, it also assumes no overcrowding. It is important to note that even with the same input data there is a different breakeven level of milk production for drying off versus culling— the difference is due to the fact that you still must feed dry cows.

Visit Virginia Cooperative Extension