The longer the milk remains in the udder, the more it is impoverished
by absorption of some of its ingredients. This is specially true of
the fats, which are taken up by the absorbent vessels of the udder
and carried into general circulation. For this reason, the first milk
drawn--which is the first secreted, and therefore remains in the udder
the longest--is the poorest milk drawn, and that which is last secreted
and last milked (the strippings) is the richest. Hence, the longer the
interval between milkings, the poorer the milk for butter making. Three
milkings a day will give better results than two.