The objective with this study was to evaluate the influence of reproductive stages (pregnancy, puerperium) and breed (Santa Inês and Morada Nova) on the hemogram. We used 20 Santa Inês sheep and 20 Morada Nova sheep diagnosed with positive pregnancy and distributed in a completely randomized design, factorial arrangement 2 × 2 (reproductive stage × breed) a in a split-plot arrangement over time (blood collection). During the experimental period, the animals were kept in paddocks containing Andropogon gayanus, which was enclosed in the late afternoon for supplementation consisting of cracked corn (70%), soybean meal (25%) and mineral supplement (5%), based on the dry matter. Blood samples were collected by jugular venipuncture every 14 d in the morning before the animals were released to pasture, starting from 1st day of gestation up to the 90th day of lactation (when the lambs were weaned). The hemogram analysis consisted of global erythrocyte counts, packed cell volume or hematocrit, hemoglobin, mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), total plasma proteins (TPP) and total leukocyte counts. The means were compared with the Student-Newman-Keuls test, and was considered significant effect when P < 0.05. There was no influence of breed in erythrocyte count (P = 0.4718) and TPP (P = 0.2609). The Morada Nova breed showed higher hemoglobin (P < 0.0001) and hematocrit (P = 0.0024) and total leukocyte count (P < 0.0001) than Santa Inês breed. There was increased in global erythrocyte counts (P < 0.0001) in pregnancy and a reestablishment during the puerperium period. The pregnancy period reduced hemoglobin (P < 0.0001), hematocrit (P = 0.0024), MCV (P < 0.0001) and MCHC (P < 0.0001) and puerperium period increased hematocrit (P = 0.0356) and total leukocyte count (P = 0.0243). The TPP also increased (P < 0.0001) during pregnancy period to compensate for the high nutritional requirements of the fetus, and these levels remained high until the end of the puerperium phase when the lambs were weaned. There is recuperation of blood values such as TPP in puerperium, which increase during this period to compensate for the high nutritional demands of the fetus in pregnancy.