INFLUENCE DES TYPES DE PATURAGES ET DES SYSTEMES D’EXPLOITATION SUR LA PERFORMANCE DES BOUVILLONS
A comparison of steer performance, as measured by body weight gains, carcass weight and quality, from ladino clover-timothy or grass pastures was carried out. Two pasture management systems were used, an extensive one with a stocking rate of 1.85 heads/ha and a moderate rate of fertilizer application, and an intensive one with stocking rate of 3.70 heads/ha and a heavy fertilizer application. Steer development followed a linear trend throughout the grazing season and steer growth was slower on the intensively managed timothy-ladino pastures than on the other pastures. The liveweight gains of the animals, per head, over the season was 10.3% greater on the grass swards than on the timothy-ladino swards, and 7.7% greater on the pastures under an extensive management system than on the other ones. Increase in stocking rate was not completely compensated for by heavy fertilization of pastures since steers grazing on high stocking rate pastures did not gain weight as rapidly as the ones on low stocking rate pastures. The amount of beef meat produced per steer (233 kilos) was not influenced by treatments. Beef carcasses from 3.70 head/ha pastures were as heavy as the ones from 1.85 head/ha pastures indicating that high stocking rate effect was balanced out by doubling the amount of fertilizers applied to pastures.