During three consecutive years,a sheep production system, with Romney Marsh sheeps,was evaluated in the Andes foot-hiils of Biobío; an imprbved subterraneum dover pasture, cv. Mount Barker, was the only feed resource used. Meat and wool productions, available dry matter (under enclosed and grazing conditions), botanical composition, chemical analysis,and digestibility were measured, in given periods oftheyear. Annual liveweight productions were 151,224 and 217 kg/ha, and dirty wool weights were 16,31 and 30 kg/ha, for each consecutive year. Stocking rates were 0.84, 1.27 and 1.42 A.U./ha, including replacements, for the three progressing season. One third of the females obtained the breeding weight (40 kg) at 6-7 months of age; and percent weaned lambs, on bred young ewes, was 25to 37%. Maximum pasture dry matter production (in enclosures) ocurred in spring each yearand was 10, 7.7 and 5.7 ton/ha, for each successive year. Maximum available dry matter, under grazing, occurred in January. The lowest value was at the end of winter, less than 0.4 tan/ha. Botanical composition showed that subterraneum dover had a variable frequency, with a maximum of 57% of the cover in September, the first year.
|1 Estación Experimental La Platina (INIA), Casilla 5427, Santiago, Chile. |
2 Subestación Experimental Humán (INIA), Casilla 761, Los Angeles, Chile.
3 Estación Experimental Quilamapu (INA), Casilla 426, Chillán, Chile.
4 Proyecto Precordillera de Biobío (lNlA-SERPLAC). Actualmente en actividad particular.