Abstract
This study aimed to assess the impact of pregnancy on biochemical indices of dairy cows raised in a semi-arid region of western Algeria. A private farm provided forty dairy cows for this study. The cows were divided into four groups based on their pregnancy stages: G1 included pregnant cows at 3 months, G2 included pregnant cows at 6 months, G3 included pregnant cows at 9 months, and G4 included lactating (calving) cows for 1‒2 months. All of the cows were raised under the same environmental and management conditions, following the regional customs. Twelve biochemical parameters were measured, including cholesterol (CHO), triglycerides (TG), total protein (TP), albumin (Alb), globulin (Glob), urea (Urea), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), calcium (Ca), phosphorus (P), and magnesium (Mg). The results of the study showed no significant difference (P > 0.05), in the concentrations of various biochemical constituents, among the four groups of dairy cows. The mean value of Glob slightly increased in early pregnancy, compared to late pregnancy, and non-pregnant cows. AST exhibited a significant difference, between non-pregnant, and early-pregnant cows. ALT levels significant decreased in late pregnant cows, compared with early-pregnant cows. Additionally, Ca levels showed a slight increase, during late pregnancy, compared to non-pregnant cows. As this is the first study of its kind on dairy cows in Algeria, the data generated during this research demonstrated the good management of the herd and can serve as valuable reference values for the scientific community.