ChileanJAR

During two seasons (1979/80 and 1980/81), at the Quilamapu Experimental Station (INlA, Chillán) a comparison was made of the liveweight (L.W.) output of two pasture mixtures: white clover-perennial ryegrass (W), and red clover-Tetrone ryegrass (R). In both pastures, a rotational grazing system, with 6 paddocks of 1.67 ha each, was employed. During all the periodof evaluation, the same W mixture was used, which was two years old when starting the data collection. For R, areas of similar size of first, second and third year pastures were used; in this case, it was considered that the mixture lasted only three years; then, each year a new sector was included, and the area util ized during three years was eliminated. For this, an adjusting period of about two years was necessary to get an stable pasture- cattle system. In the spring and autumn seasons of each year, 6-month-old steers of 158 kg of L.W. entered to each pasture, replacing the animals which left the system. A fix stocking rate was kept in each pasture and the grazing pressure was adjusted by making hay of the forage surplus. Fifty per cent of the land was cut once ayear (spring season), with an average yield of 1.96 al'ld 2.77 Ton D.M./ha, for Wand R, respectively. Mean L.W. output, adjusted to harvested area, for both seasons, was: 438 and 510 kg/ha, for Wand R, respectively. Annual stocking rate was 6.2% higher for R. When leaving the pastura, steers reached a L.W. of 333 and 355 kg, at 18 months old (spring calving). and 466 and 489, at 24 months old (autumn calving), for Wand R, respectively. Gross income and profit margin were slightly higher for R.