Efecto de la suplementación invernal con grano de lupino o afrechillo de arroz sobre la performance de terneras pastoreando campo natural

The objective of this work was to evaluate the response to daily supplementation with lupine grain and rice bran during the winter, in conventionally weaned calves grazing natural fields. This response was evaluated in terms of live weight gain and weight at the end of winter, and efficiency of supplement use. Additionally, as interpretive variables, the effect of supplementation with these foods on forage utilization and ingestive behavior of grazing animals was characterized. The experiment was carried out in a commercial establishment, located in the Salto area, east of the department of Salto (geographic coordinates 31º 29'50'' South latitude and 57º19'06 West longitude). The experimental area was 31.5 hectares, which was subdivided into 3 plots of 10.5 hectares. The experimental work lasted 71 days, from July 12 to September 21, 2022. 48 calves were used with an initial live weight of 158 ± 3.2 kg, which were randomly divided into batches of 3 animals. The experiment presented a randomized plot design with the animal being the repetition. In each treatment, 16 calves were used, which grazed the natural field continuously, with an adjusted load of 1.52 calves per hectare, a treatment called lupine, where there were animals that, in addition to grazing natural fields, had access to grain. lupine and another treatment called rice bran, which had access to that food. The average daily gains in live weight obtained in the Control, bran and lupine treatments were -0.2 kg/day, 0.18 kg/d and 0.30 kg/d respectively, achieving an Ec of the supplement of 4.1 to 1 with rice bran and 2.2 with 1 with lupine grain.