ChileanJAR

Twenty spring born calves of the Overo-negro breed were used, to evaluate their productive performance, when fed two milk diets: naturally fermented colostrum (CN) and acidified colostrum preserved with formalin (CF) 0.1 % vol./vol. Both were given at the environment temperature (4 It, in two daily rations) up to 40 days of age and then acidified milk was fed up to 75 days. Animals were managed individualy the first week, in indoor cages, and then under grazing, up to 90 days of age. Calves were also given: a starter concentrate, ryegrass-white clover hay, and grazing of a permanent pasture ad lib. Water was offered ad lib, in two oportunities each day up to weaning and then additionally at the times of the milk diet rationing. Consumption of the milk diets was measured, as well as concentrate, hay and grazing area of the permanent pasture. Calves were weighed weekly. Live weight gains (kg/day) and accumulated weights up to weaning and 90 days, showed no statiscal differences; also, feed intake was similar (P > 0.05). The fermentation of colostrum had no difficulties, but the general aspect of CF was better than CN and it was consummed better by the calves, although this did not originate productive differences. At the end of the season, both groups showed a good rhythm of growth and development.