The experiment was conducted to evaluate the performance of beef heifers with average age of ten months and average initial weight of 200 kg, grazing cultivated annual temperate grasses mixtures supplemented with salt plus lasalocid or salt. Spread sowing ocurred on 04/21/95, being the area fertilized with 200 kg/ha of 05-30-15. Nitrogen fertilization in the form of urea (175 kg/ha of N) was subdivided in four applications. The establishment of the pasture occured from 04/21 to 06/08 and the experimental period occured from 09/08 until 11/14. Salt and salt plus lasalocid were supplied weekly. Quantity of lasalocid supplied in the mixture was 225 mg/animal/dia. Addition of lasalocid did not affect average daily weight gain (.842 vs .852 kg), but resulted in a no significant increase of 7% in stocking rate (1382 vs 1292 kg/ha), 6.9% increase in weight gain per ha (347.8 vs 325.5 kg), 6% better feed efficiency (8.56 vs 9.07 kg DM/kg of live weight gain), and increased cost of pasture utilization in R$ 11.50/ha providing an increment in net income of R$ 15.30/ha.
animal performance; cost; feed efficiency; ionophore; net income; stocking rate
