Investigation of the potential ingestion rates of different sourveld grasses by cattle and sheep

Abstract

Quantification of the potential ingestion rates of different grasses is important for modelling purposes but is difficult to achieve under field conditions. The ingestion rates of the sourveld species Alloteropsis semialata, Andropogon appendiculatus, Cynodon dactylon, Eragrostis plana, Heteropogon contortus, Hyparrhenia hirta, Themeda triandra and Tristachya leucothrix were determined by presenting plants growing in pots to confined sheep and a single steer. Sheep intake rates were highest for H. contortus (6.82g DM min^-1) and lowest for A. appendiculatus (4.01g DM min^-1) but most between-species differences were non-significant. Steer intake rates were highest for E. plana and A. semialata (32g DM min^-1) and lowest for H. hirta (24.3g DM min^-1) but again, most between-species differences were non-significant. The results obtained suggest that there is little difference in the potential ingestion rate of most sourveld species and indicate that the methodology employed has potential as research tool.

Keywords: alloteropsis semialata; andropogon appendiculatus; bite rate; bite size; botany; cattle; condition; cynodon dactylon; döhne agricultural development institute; eragrostis plana; grass; grasses; heteropogon contortus; hyparrhenia hirta; ingestion; intake; intake rate; methodology; modelling; plant structure; plants; quantification; sheep; sourveld grass; south africa; themeda triandra; tristachya leucothrix

African Journal of Range & Forage Science, Vol. 13(2), pp. 49-53