There is now considerable evidence of residual effects of both energy and protein supply during the dry period on performance in the next lactation. Changes in forage intake and eating/rumination behaviour in the dry period have been implicated in predisposition to metabolic disorders in the subsequent lactation. In particular, there is a close association between intake either side of calving (Grummer, 1995). The primary objective of this experiment was to identify the effects, and interactions, of pre-partum energy and protein supply on forage intake and particle size reduction (as an index of rumination behaviour) of cows in the dry period.

Fifty-two Holstein-Friesian cows, calving from September to November 1996, were used in a continuous design experiment The cows were dried off 8 weeks before their anticipated calving date and grazed on bare pasture for one week before training to use Calan gates (using grass silage only).