Forty crossbred heifers, mated to one sire, that calved in a 20-day period were used to study the effect of varying time and level of post-partum nutrition on productivity. Heifers were individually fed for 90 days post partum beginning at parturition: (1) proportionately 1·3 National Research Council (NRC) 1984 recommendations for 45 days followed by 0·7 NRC for 45 days (130·70); (2) 1·0 NRC for 90 days (100·100); and (3) 0·7 NRC for 45 days followed by 1·3 NRC for 45 days (70·130). Milk production, growth and body condition were estimated periodically during the lactation. The 130·70 heifers maintained their weight during the first 45 days of lactation, while the 100·100 and the 70·130 heifers lost weight (−0·33 and 0·60 kg/day, respectively). During the second 45-day period, the 100·100 and 70·130 heifers gained weight (0·24 and 0·72 kg/day, respectively) while the 130·70 heifers lost weight (−0·39 kg/day). Visual condition scores paralleled weight changes during both phases of the feeding period. Milk production varied according to nutrient intake and treatment differences were greatest at 45 days post partum (8·1, 7·3 and 6·1 kg/day for 130·70, 100·100 and 70·130, respectively). Calf weight gains were unaffected by dam nutrition. Days to first oestrus, days to conception or services per conception were not significantly different (P > 0·05) among treatment groups. Based on this experiment, neither of the alternate feeding systems resulted in decreased performance when compared with feeding at a constant level. Therefore, it appears that latitude exists in the way heifers can be fed early in their first lactation, without adversely affecting production.