A total of 72 spring calving (mean calving date: March 8;
range: 4 February–14 April) Holstein-Friesian primiparous
(n=32) and multiparous (n=40; parity range of 3 to 8)
cows were used. Cows were blocked into groups of 4 based on
expected calving date, milk yield during the previous lactation
(if multiparous) and lactation number. One cow from each
block was randomly assigned to 1 of 4 treatments in a 2×2
factorial design for the entire lactation; OAD or TAD milking, at
a high or low nutritional level (NL)