Herbage height as a determinant of the preference of steers grazing three pasture species

Abstract

Steers grazed Rhodesgrass, kikuyu and Coastcross II pastures in high utilization (HUG) and high production (HPG) rotational grazing systems. Grass tillers were marked and monitored to establish height preferences shown by animals. Generally, longer herbage was selected on all three grasses compared to herbage that was rejected. Herbage height and amount grazed was linearly correlated (r = 0,43 to 0,87) but these relationships differed for different situations. In Rhodesgrass 60% of the tillers were uprooted by the end of the grazing period while in kikuyu 32% and Coastcross II 17% were uprooted. In all three grasses tillers that were uprooted were shorter than those which remained rooted after grazing.