The aim of this case study was to evaluate the clinical and productive data of Nellore cows during pregnancy and lactation, supplemented or not with P. Ninety-five pregnant heifers were divided into two groups (G40 and G0). Until the date of calving animals from G40 received a mineral mixture composed of 224g of Na and 40g of P/kg, and G0 received only NaCl. After calving heifers were divided into four treatments: from G40, 28 first-calf cows continued to receive the mineral mixture containing 224g of Na and 40g of P/kg (group 40/40) and 12 started to receive only NaCl (group 40/0); from G0, 26 continued to receive only NaCl (group 0/0) and 15 started to receive a mixture containing 224g of Na and 40g of P/kg (group 0/40). In the second experimental phase, 205 multiparous cows were divided into two groups: G1 (40/40) consisting of 40 cows, receiving a mineral mixture containing 244g of Na and 40g/P per kg, during pregnancy and lactation, and group 2 (0/0) formed by 165 cows, which were supplemented only with NaCl. In both experiments, whether in pregnant or lactating breeders, there was not any sign of P deficiency or differences in calves LW at 120 and 210 days.