Grazing management was based on a
rotational grazing system, and cows were allocated fresh grass
after morning milking. High and low NL cows grazed to a postgrazing
sward height of 83 mm and 68 mm respectively. Herbage
allowances were: high NL TAD=30.6; high NL OAD=32.0;
low NL TAD=19.4 and low NL OAD=18.6 kg DM per cow/d,
respectively. Actual grasses removed per cow/d in the groups
were: high NL TAD=19.3; high NL OAD=19.7; low NL
TAD=14.6 and low NL OAD=14.0 kg DM. Paddocks were
topped by mechanical means to maintain pasture quality across
treatments. Due to drought conditions and grass scarcity, between
1 July and 3 August cows on the high NL and low NL
treatments were provided with 3 and 1 kg/cow per day of concentrates
in addition to their grass allowance. This was reduced
to 2 and 1 kg/cow per day between 4 and 11 August, when
concentrate was again removed from the diet