Abstract 163

Lascano,CE; Thomas,-D

Tropical Pastures Programme, CIAT, AA 67 13, California, Colombia.

Grass-and-Forage-Science. 1988, 43: 4, 433-439; 19 ref.

A small plot grazing trial was conducted in the Eastern Plains of Colombia to assess seasonal forage quality and selection by oesophagealfistulated steers of Arachis pintoi associated with 4 Brachiaria spp. Quality of the legume was high in terms of leaf CP (17%) and in vitro DM digestibility (IVDMD) (62%) but varied with season of the year. Associated grasses had high average leaf CP levels in the dry (7.8%) and wet (9.8%) seasons. The legume content in the forage on offer was high and varied from 28% in the dry season to 58% in the wet season. Corresponding values in the diet selected were 37% and 60%, indicating that animals selected the legume in a slightly higher proportion than was present in the total forage on offer. This was further confirmed by selection indices >0.5 in 3 of the 4 associations and by a selection index of 0.56 when pooling the data for the 4 pastures. Increased grass quality and high legume selection resulted in a high quality diet in the dry (CP 9.7%; IVDMD 61%) and wet (CP 15.6%; IVDMD 62%) seasons. The results indicated that A. pintoi is a high quality legume, well accepted by grazing cattle throughout the year in the savannas.