Thirty female Holstein x Zebu crossbred calves were used since 7 d of birth up to weaning at 90 d in a completely randomized design with 10 repetitions to assess two milk replacer formulas in the lactation stage (from 7 up to 30 and from 31 d up to weaning). They were intended to be used as substitutes in animal feeding. All the female calves remained next to their dams during the first 48 h They were fed 2 L of colostrum from the milking after the birth and at 12 h. At the third day, they were allocated in individual cradles, being supplied 5 L of colostrum and transition milk up to 6 d of age. Since the seventh day, they were distributed in the following treatments. A) 4 L of whole milk from 7 to 90 d (control), 13) 4 L of whole milk from 7 to 30 d and 500 g of Relac from 31 to 90 d, and C) 500 g of Maxicare From 7 to 30 d and 500 of Relac from 31 to 90 d. All the female calves were fed reconstituted milk replacers at 12.5 % concentration and temperature of 50-60 degrees C and the feed at 38-40 degrees C Since 45 to 90 d, they were given a complete ration ad libitum with 20 % sugarcane meal There were no differences in liveweight or daily weight gain throughout the experimental period between treatments. Nevertheless, 240 L of whole milk were substituted in treatment 13 and 336 L in C using Maxicare and Relac milk replacers, according to the treatments. Besides, the feeding costs per calf were reduced from A (S 212 24) to C (S 50.20). It is concluded that it is possible the rearing of replacement calves combining Maxicare milk replacer from 7 to 30 d and Relac milk replacer from 31 to weaning, as well as the substitution of the whole milk they consumed with liveweight gains higher than 550 g/d in the lactation period.
