These authors reported a positivecorrelation between cisternal area and cisternal milk volume that was highest in the 8- to 12-h period after milking (r = 0.88, 0.80, and 0.84 with 8-, 10-, and 12-h milking intervals, respectively) and lowest at longer milking intervals (r = 0.63, 0.51, and 0.46 with 16-, 20-, and 24-h milking intervals, respectively).