Claudio Rojas G.1, Adrián Catríleo S.1 y Ricardo Campillo R.1
A grazing and finishing system with 7-8 month-old Holslein x European friesian steers integrated to a crop ratatian was evaluated during 5 seasons. The crop rotation considerad oats (Avena sativa L.), rapeseed (Brassica napus L.), wheat (Triticum aestivum L.), and two years of a mixture of red clover (Trifolium pratense L.) and Italian ryegrass (Lolium multiflorum Lam.). Oat was usad according to animal requirements fer both winter grazing and as a source of grain or straw. Additionally, oat used fer winter grazing was also utilized for silage. Rapeseed and wheat were produced far industrial purpose only, while pastura was produced far grazing and conservation. Growing steers were incorporated to the system in April each year in the first week of April grazing pasture for the following 12 months. Second year pasture were grazed from April to July, and the animal were also supplemented with hay or silage. In June, July and August, the steers grazed winter oats. From August to March, only pasturas, under a rotational system were grazed. The steers were finished at a feedlot with pastura silage ad libitum and a concentrate basad on oats grain and rapeseed meal. Average yields of wheat, rapeseed and oats in the system were 5,978; 2,443 and 4,314 kg per hectare, respectively. Ory malter production was 10,960 and 9,043 kg/ha for the first and second year pastura, respectively. Stocking rate increased gradually tram 12 to 22 steers in five year. Initial liveweight (LW) at grazing was, on average, 193 kg/steer and final liveweight of 418 kg per animal. At the feedlot, alter a 84 days period, final LW was 503 kg/steer. Considering the whole cycle, total liveweight production of pastures and oat consumed was on average, 701 kg/ha and the potential yield reached 874 kg/ha. Pasturas and culture evolution, soil fertility and animal weight gain were also recordad in the system.
Key words: steers, breeds, seeding system, finishing, crap ratatian, Avena saliva, Brassica napus, Triticum aestivum, Trifolium pratense, Lolium multiflorum, IX Region.
1 Estación Experimental Carillanca (lNIA), Casilla 58-D, Temuco, Chile.