The cumulative effects of daily herbage allowance (DHA) restriction on pasture
characteristics and the sustainability of pasture-based dairy systems were evaluated. Sixty-four
dairy cows were randomly assigned to one of two grazing treatments (20 and 30 kg DM cow-1
day-1). Milk yield and pre- and post-grazing herbage mass were recorded for every grazing
event. Botanical and chemical compositions of the pasture were evaluated. Low DHA increased
the stocking rate by 0.7 cows ha-1 and consequently increased grazing efficiency from 41 to 47%.
Daily herbage allowance restriction did not affect pasture characteristics or milk production per
cow, but DHA restriction increased milk production per hectare (+27%). The results suggest
that restriction on daily herbage allowance ensures a higher level of herbage utilization and
milk output per ha than high DHA, without affecting pasture characteristics. Therefore, DHA
might be a useful grazing management tool for improving the profitability and sustainability of
grazing-based dairy systems.
