[Effects of grazing pressure on ingestive behavior and voluntary intake of sheep on pasture]

The effects of three levels of grazing pressure (4, 10, and 16 kg of organic matter/100 kg of body weight per day) on the ingestive behavior and voluntary intake were evaluated with six sheep grazing a predominantly perennial ryegrass pasture, using a duplicated Latin square design. Voluntary intake decreased from 3.58 to 1.67 kg ol organic matter/100 kg of body weight per day with increasing levels of prating pressure, which negatively affected ail parameters of ingestive behavior expressed as a fraction of intake (minutes or number/g organic matter/kg(.75) per day). Decreasing levels of grazing pressure allowed higher intakes by increasing the rate of intake, probably due to a greater ease of herbage prehension by sheep