Effect of two grazing frequencies on permanent pastures

Enrique Siebald Sch.1, Ljubo Goic M.1 y Mario Matzner K.1

During five years (1982-1987), using a permanent pasture fertilized yearly for more than eleven years, two pasture systems were compared, at the Remehue Exp. Sta. (INIA-Osorno): daily rotational grazing versus a control group (rotational·grazing of five paddocks only). A similar stocking rate (4 fattening calves/ha) was used, that was doubled in spring and reduced in summer, according to weather conditions. No forage conservation was done, and a mineral mixture was the only supplement offered. Rotation periods varied from 18 to 60 days, according to the season. Each management system had two replications, with 3 ha each. No differences were observed in dry matter (D.M.) production, reaching approximately 9 ton D.M./ ha; this is relatively low, due to the high utilization intensity. There were no differences in botanical composition, and a tendency for a higher production in L.W./ha was observed with daily rotational grazing, specially during 1984/85, that followed a great summer drought (23%; 827 vs 670 kg L.W./ ha). Also, in this treatment higher weight gains were observed during the critical winter period. With normal summer weather conditions, a tendency for higher productions was observed, reaching 1,100 kg L.W./ha, in both systems during the last period studied (1986/87).

1 Estación Experimental Remehue (lNIA), Casilla 24-0, Osorno, Chile.