Ignacio Ruiz N.1, Germán Klee G.2 y Rolando Fuentes V.3

During 112 days of the winter of 1978 a trial was carried out at the Quilamapu Experimental Station, Chillán, Chile, in orden o study a wide range of sugar beet molasses in winter finishing rations of steers.
Forty Holstein Friesian steers of 400 Kg of body weight and two years old were assigned to the following five treatments: 0.0; 0.6; 1.2; 1.8 and 2.4 Kg of molasses (air dry basis) per 100 Kg of body weight. The rations contained 0.300 Kg of rapeseed meal per 100 Kg of body wight and variable quantities of urea so that he total protein was equalized to 0.313 Kg per 100 Kg of body weight. Wheat straw was used to give volume to the diet. All the animals received 200 g of mineral mixture based on three parts of bones meal and one part of salt.
Daily gain of the steers increased continuously with an increase of molasses consumption. The best equation that represented the response of the steers to the level of molasses was: Y = 0.00014 + 0.5589X - 0.12056X2 (r2 = 0.97; P < 0.01), where Y: change in live weight (Kg/day) and X: Kg of molasses consumed per 100 Kg of live weight. Molasses consumed up to 2.4 Kg day/100 Kg live weight (an average of 10.46 kg air dry basis/steer) apparently did daily gains were lower than those expected theoritically. for prices prevailing in 1978, it was found that net income and renability increased as molasses in the ration was increased.

1Ing. Agr., Ph.D., Estación Experimental Quilamapu, Insti.tuto de Investigaciones Agropecuarias (INIA), Casilla 426, Chillán, Chile. Profesor Universidad de Concepción.
2Ing. Agr., Subestación Experimental Humán, Instituto de Investigaciones Agropecuarias (lNIA), Casilla 767, Los Angeles, Chile. 3Ing. Agr., Estación Experimental Quilamapu, Instituto de Investigaciones Agropecuarias (INIA), Casilla 426, Chillán, Chile.