Level of colostrums' enzymatic activity is a reliable indicator of ingestion and passive immunity and, thus, the viability of newborns. Our study evaluated the colostrums immunoglobulin-G (IgG) and enzymatic levels during the first 24 h after lambing in ewes and determined the effect of fixed factors on enzymatic quality. Colostrums were milked from 134 Ouled Djellal ewes aged from 1 to 8 years in a commercial farm of Algerian semi-arid region. Samples were taken at 3, 6, 9, 12 and 24 h after lambing and alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT) and lactate dehydrogenase (LDH) levels were determined in colostrums using the spectrophometric analysis (Spin react). The IgG quality of each sample was measured using a digital brix refractometer (PAL colostrum-58%). Results showed significant differences related to milking period, lambing season and animal. Period of milking had significant effect on ALP (p < 0.01) and GGT (p < 0.05) activities, respectively. The highest enzymatic activity in ewe colostrums was observed in spring, in both lean and fat ewes. Enzymatic activity decreased with age until 5 years old and increased thereafter. GGT and LDH activities can thus be used alongside IgG in the determination of colostrums immunological quality, but ALP cannot.