In winter, the food must be in proper condition, properly balanced
between the nitrogenous and carbonaceous materials, and in full
supply--all the cow can digest and assimilate. At least one ration a
day should include sweet ensilage, roots, or other succulent food, to
aid in the separation of the butter from the cream by action of the
churn, it having been shown that all dry feed not only reduces the
flow of milk, but makes churning slow and difficult, leaving a large
percentage of fat in the buttermilk.