Abstract 496

Dixon,-RM

Inst. Produccion Animal, Facultad de Agronomia, Univ. Central de Venezuela, Maracay, Venezuela.

Tropical-Animal-Production. 1984, 9: 1, 30-34; 9 ref.

In a change-over experimental design the Holstein cattle, 4 bulls initially of 203 to 222 kg and 3 heifers initially of 140 to 180 kg were given Pennisetum purpureum forage of 60 to 65 days regrowth freely, 0.25% of their weight of a mixture with sesame seed meal, minerals and salt, and a molasses-urea supplement none, 0.2, 0.4 or 0.8% of their weight on a dry matter (DM) basis. The supplements were always eaten completely. Intake of forage was measured daily and the animals were weighed weekly. Forage DM intake in the absence of molasses was high, 2.96% of their weight, and there was a linear depression in forage intake with increasing molasses supplement (substitution rate 0.62 kg forage DM/kg molasses DM). Weight gain and feed conversion were not significantly different between the different molasses supplements and were 723 ñ s.e. 121 g daily and 11.4 ñ s.e. l.4 kg intake/kg gain respectively. The results demonstrated that total DM intake was not increased substantially by supplements of mature tropical forage with molasses-urea, owing to the replacement of forage by supplement.