Abstract
Brachiaria humidicola Schweickt 'CIAT 679', Brachiaria decumbens Stapf cv. 'Basilisk' and Andropogon gayanus Kunth cv. 'Carimagua l' were tested in association with Desmodium ovalifolium Wall. 'CIAT 350' in three one grass-one legume associations grazed by Criollo x Zebu cross-bred heifers over a period of 555 days in the eastern plains region of Colombia (Llanos Orientales). B. humidicola produced the highest growth rate and the highest total (grass + legume) dry matter (DM) yields. Both Brachiaria species showed significantly better growth rates than A. gayanus. Annual DM yields for the three associations of B. humidicola, B. decumbens and A. gayanus with D. ovalifolium were 19.43, 14.30 and 8.57 t ha-1respectively. There were no significant differences in the total yield and the mean growth rate of the legume in association with the two Brachiaria spp. Legume contents in the presentation yields of the three mixtures ranged from 42 to 46%. D. ovalifolium exhibited its ability to compete with B. humidicola, the most productive of the three grasses and these two species formed a highly compatible association.