ABSTRACT


Ignacio Ruiz N.1, Ernesto Jahn B.2, Germán Klee G.3, Marcos Figueroa R.4 y Alejandro Ayres M.5
 

An experiment was carried out during 1969-70 at the Quilamapu Experiment Station, Chillán, to study the influence of 3 rates of winter gain of Holstein steers from 8-12 months of age period (first winter of spring-born claves) on a total beef production system based on a year-round forage program.
The treatments and results were: a) High winter gain (0.79 Kg/day) obtained by winter grazing plus a dry sugar beet pulp-rapeseed meal supplement; b) Medium gain (0.38 Kg/day) obtained by grazing plus hay harvested from the forage plan, and c) Maintenance (-0.02 Kg/day) obtained with grazing alone. In the subsequent spring-summer-fall grazing season, the steers at the maintenance level showed the highest daily gain, but by fall they did not reach the live weight of steers from the other treatments; thus at the beginning of the second winter the steers 20 months old were not heavy enough to complete winter fattening within a 2 years-system of production. After the grazing period, the steers of all treatments were fed with a similar winter fattening ration (20-24 months of age).
The treatments markedly influenced the carrying capacity and the output per hectare as well as the time to reach market weight (500 Kg).

Keywords:
1Ing. Agr., Ph. D., Estaci6n Experimental Quilamapu, Instituto de Investigaciones Agropecuarias (INIA), Casilla 426, Chillán, Chile.
2Ing. Agr., M. S., Subestación Experimental Humán, Caoilla 767, Los Angeles, Chíle. Actualmente en V. P. I. y S. D., Blacksburg, Virginia.
3Ing. Agr., Subestación Experimental Humán, Casilla 767, Los Angeles.
4Ing. Agr., M. S., Estación Experimental Quilamapu, Chillán.
5Ing. Agr., Estación Experimental Quílamapu. Actualmente funcionario del Servicio Agrícola Ganadero (SAG)