Velasquez, 1990. Livest. Res. Rural Dev., 2 (3): 78

This experiment was carried out at the 'Centro Regional de Investigacion `Macagual'' in an ultisol of the Amazonian Piedmont, located in Florencia, Colombia at an elevation of 250 metres above sea level, with 26°C mean temperature, 3500 mm annual rainfall and a relative humidity of 80%. During three years, three stocking rates of 1.5, 2.0 and 2.5 steers (280 kg initial mean live weight) per hectare were compared in a pasture of Brachiaria decumbens under continuous grazing in order to determine the animal productivity and the carrying capacity of the grass, in a completely randomized design without replications. The mean annual productivity on each stocking rate was 197¦9.2, 189¦9.1 and 204¦4.6 kg/animal, respectively, and no significant differences were found (P>0.05), although during the dry season the average daily gain in the higher stocking (646 g), was significantly higher (P<0.05) than the average daily gain in the medium and low stocking rates (493 and 531 g), respectively. The year effect was highly significant (P<0.001) both in the dry season and in the rainy season; in the dry season, the average daily gain in the first year (724 g), was higher than that of the second and third years (454 and 416 g), respectively. During the rainy season the average daily gain in the first year (389 g) was lower than that of the second and third years (572 and 627 g), respectively. Differences in the annual average daily gain were not significant (P>0.05), due to an equal availability of the green dry matter during the three years of the experiment. Growth of animals on Brachiaria was 46% higher than in the Amazonian piedmont in this study: more information is needed in relation to Brachiaria management, fertilization and control of the `spittle bug' insect.