The relationshipbetween pasture dynamics and ingestive behavior of female lambs was studiedon Italian ryegrass (Lolium multiflorum Lam.) plus red clover (Trifoliumpratense L.) mixture under a range of defoliation intensities. Rotationalgrazing was used and the grazing interval was determined by the thermal sumof 313 degree days. The initial pre-grazing canopy height disappearance valueswere 65 (very high), 58 (high), 47 (medium) and 37% (low). The sward verticalstructure was similar among defoliation intensities. The forage allowance decreasedlinearly as defoliation intensities increased, with 0.35 bite/minute reductionfor each 1% increase in forage allowance. The bite rate and number of bites/feedingstation decreased with reduced contribution of leaves in the sward structure.It was associated, respectively, with an increase and a decrease of NDF andCP levels in forage as grazed by female lambs. The pasture cycle proves to bemore important than defoliation intensities as a source for changes in feedingstations and displacement patterns of female lambs.
