THE EFFECT OF DIETARY ENERGY CONCENTRATION ON CALF PERFORMANCE

At three locations, 120 calves were fed a high fat milk replacer at 10 % of birth weight from d 5 through 13. On d 14, calves were assigned r andomly within sex and date of birth to a 2 x 2 factorial arrangement of treatments. Treatments were (on a DM basis) high fat milk replacer (21.6%) and high fat starter (7.3%), high fat milk replacer (21.6%) an d low fat starter (3.7%), low fat milk replacer (15.6%) and high fat s tarter (7.3%), and low fat milk replacer (15.6%) and low fat starter ( 3.7%). Milk replacer was fed at 8% of birth weight/d from d 14 to 35 a nd at 4% of birth weight/d from d 36 to 42. High fat replacer depresse d DMI before and after weaning. High fat starter depressed DMI after w eaning. Before weaning, calves gained more BW when fed low fat replace r. Calves fed low fat starter gained more BW after weaning. On d 56, B W were highest for calves fed low fat replacer and starter and fewest for those fed high fat replacer and starter. Growth or health of calve s was not improved by fat addition to the diet.