Big cows need big beds. It's really as simple as that, says Zen Miller, a University of Wisconsin dairy Extension educator based in Appleton.
"We used to build freestall barns based on the number of stalls we wanted to get into a barn,” he says. "But we've since learned that doesn't work very well.
"Now we've learned to let the cows decide how big their freestalls should be. It's just logical,” he says.
So rather than size all stalls 4' wide and 8' long, you need to know at what size your cows reach full maturity. For example, if you're milking Jerseys or Jersey/Holstein crossbreds that mature at 1,000 or 1,200 lb., the 4'x8' stalls are adequate (see table below).
But if you're milking Holsteins with Canadian genetics thrown in, those 1,800-lb. behemoths require stalls that are 4½' wide and up to 10' long if the stalls face a wall. You need that length just to allow enough lunge space for the cows to rise naturally, Miller says.
"A ‘doghouse' can be added to the outside wall of an old freestall barn to fix the length of the outside freestall,” Miller says. "This addition can be as high as the eaves or just about half the height of the outside wall, thus the ‘doghouse' effect. When you do this, your back curb does not have to be moved.”
These king-size stalls aren't necessary for first-calf heifers. So having a separate heifer group, with appropriately sized stalls, is ideal.