The purpose of this study was to evaluate the physiological variations and influence of age group and sex on biochemical variables of 32 male and female Dorper sheep at the age of 15 to 121 days. Four blood samples were collected from each animal, at monthly intervals, totaling 128 samples. Biochemical variables determined in each sample were total protein (TP), albumin (ALB), globulin (GLB), albumin/ globulin ratio (A/G), glucose (GLU), triglycerides (TG), total cholesterol (tCHOL), high density cholesterol carrying lipoproteins (HDL-C), low density cholesterol carrying lipoproteins (LDL-C), very low density cholesterol carrying lipoproteins (VLDL-C), urea, creatinine (CRE), total calcium ( t Ca), ionized calcium ( i Ca), phosphorus (P), calcium/phosphorus ratio (Ca/P), magnesium (Mg), sodium (Na), potassium (K), chloride (Cl), alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT) and alkaline phosphatase (ALP). The results were obtained in four moments according to age: M1 -sheep from 15 to 30 days, M2 -sheep from 45 to 61 days, M3 -sheep from 74 to 90 days and M4 -sheep from 105 to 121 days. Comparing the values of the biochemical variables among the four age groups studied a significant difference (p < 0.05) was observed in the concentrations of all the variables evaluated except for Na, Cl and ALT. Sex did not influence (p > 0.05) the values of the biochemical variables analyzed. Based on the results, it is concluded that the age groups exert a significant influence on the majority of blood biochemical variables of Dorper sheep from 15 to 121 days of age.
