Egypt. J. Vet. Sci. Vol. 54, No. 4, pp. 571-577 (2023) P REGNANT animals need high energy to maintain pregnancy and embryo development. Animals supplemented with low energy diets are predisposed to infammatory processes, immune system dysfunction, and maternal metabolic issues during pregnancy. This research work aimed to declare the changes in hemato-biochemical parameters in pregnant Rembi sheep. Thirty healthy Rembi ewes were synchronized in October 2020 for the current study. Beginning in the frst month of pregnancy, blood was taken monthly from the jugular vein. Our results showed that plasma glucose (GLU), urea, and globulin(Glob) decreases were highly signifcant (P<0.05) during the last two months of pregnancy. Conversely, the values of triglyceride (TG), Albumin (Alb), Alanine Aminotransferase (ALT), and Aspartate Aminotransferase (AST) recorded a highly signifcant increase at the end of the pregnancy. Furthermore, serum levels of Calcium (Ca) and Phosphorus (P) recorded a highly signifcant (P<0.05) decrease during the last month of gestation. Total protein (TP) and Gammaglutamyl Transferase (GGT) showed signifcant (P<0.05) decreases during the frst gestational month. Regarding the hematological parameters, especially erythrogram, in the last month of gestation, ewes present macrocytic hypochromic anemia with a highly signifcant (P<0.05) decrease in the values of red blood cells (RBC) and hemoglobin (HBC). White blood cells (WBC) were found to be signifcantly higher (P< 0.05) in the fnal month of pregnancy compared to the frst. Blood parameters may change during pregnancy, and that can refect the health of the ewes. Keywords: Ewe, Biochemical Parameters, Hematological Parameters, Pregnancy, Rembi. 52 Hematological and Biochemical Blood Parameters During Pregnancy in Algerian Rembi Ewes Chikhaoui Mira 1,2 , Hariche Zahira 1 , Aiche Souad 1 , Smail Fadhéla 1,2 and Berrani Abdelkader 3 1 Department of Animal Health, Veterinary Institute, University of Tiaret, Algeria. 2 Laboratory of Research on Local Animal Products, Tiaret University, Tiaret, Algeria. 3 Faculty of Nature and Life Sciences, University of Tiaret, Algeria. Egyptian Journal of Veterinary Sciences https://ejvs.journals.ekb.eg/ Corresponding author: Mira Chikhaoui, , E- mail: zaoiraomar@yahoo.fr, Tel.: (213) 776568734 (Received 04/01/2023, accepted 03/04/2023) DOI: 10.21608/EJVS.2023.185405.1422 ©2023 National Information and Documentation Center (NIDOC) Introduction In Algeria, sheep represent the highest domestic animal population. They are important to the country’s economy, particularly in meeting population needs such as meat and wool [1]. In 2017, the Algerian steppes had an important growth in livestock numbers, which increased up to 28 million ovine heads [2]. The classifcation of the Algerian sheep population based on mapped breeding zones in the study of Djaout et al. [3] showed that 12 ovine breeds are phenotypically characterized. Rembi sheep is an important breed in livestock farming in Algeria; it is well adapted to extreme cold and mountain conditions and is known by its cold and drought resistance [4]. This breed is predominant in the regions of Ouarsenis and the highlands of Tiaret, west Algeria [3]. Several studies have shown great variation in the hematological parameters during the different pregnancy stages in small ruminants [5, 6]. According to Plaza Cuadrado et al. [7], blood biochemical parameters are important indicators of metabolic activity in ewes. As per the stages of life,