Abstract
Background:
The final stages of gestation in ewes are periods with very high energy requirements, with the energy needed to maintain homeostasis rising by 50%–75% compared to non-pregnancy conditions. However, mitochondrial activity can be reduced by oxidative stress induced in late pregnancy.

Aim:
This study aimed to evaluate the effects of propolis and rosemary extract on mitochondrial enzyme activity, energy metabolism, and oxidative stress in late-pregnant Awassi ewes.

Methods:
The study sample comprised 24 multiparous Awassi ewes in the late stages of pregnancy (140 ± 5 days of gestation). Animals were divided into four groups (Group I: control, Group II: propolis (5 g/day), Group III: rosemary extract (1.2 g/head/day), and Group IV: combined propolis + rosemary treatment) using a completely randomized design. The activities of Adenosine Triphosphate (ATP) synthase and cytochrome c oxidase were analyzed in liver biopsies using spectrophotometric methods. Malondialdehyde (MDA), glutathione, superoxide dismutase (SOD), Catalase (CAT), and Glutathione Peroxidase (GPx) levels were analyzed using serum samples.

Results:
Propolis and rosemary extract, as well as their combined use, had a significant effect on the activity of adenosine triphosphate synthase and cytochrome c oxidase enzymes in the mitochondria of liver cells when compared to the control group. The activities of ATP synthase were increased by 43% and 38%, respectively, and the values of cytochrome c oxidase activity in the same groups were increased by 52%, 47%, and 71%, respectively (p < 0.05). The levels of ATP in the liver of pregnant ewes supplemented with propolis, rosemary extract, and both were 34%, 38%, and 41% higher than those in the control group (p < 0.05). The MDA content in the liver of ewes receiving propolis, rosemary extract, and the combination of both was 31%, 35%, and 45% lower, respectively, than that in the control group (p < 0.05). The activities of the antioxidant enzymes SOD, CAT, and GPx in the liver of pregnant ewes in the three groups were higher than those in the control group and increased by 28%–52%.

Conclusion:
Propolis and rosemary extracts play an important role in regulating oxidative stress and increasing energy metabolism in the liver mitochondria of pregnant ewes during late pregnancy.

Key words: ATP synthase; Bee glue; Oxidative stress; Pregnancy; Saliva rosmarinus extract.