The study was performed on two groups of lambs: control (CG) and experimental (EG) in which diet was supplemented with Saccharomyces cerevisiae yeast extract. At 100 day of life, 13 lambs from each group were weaned, fasted for 12 h and, on the following morning, transported to the slaughterhouse. Lambs were weighed and subjected to blood sampling before weaning (Blood Sampling Time (BST 1), before transport (BST 2) and after transport (BST 3). After 24 h of carcass chilling, ultimate pH (pH_u) and colour were determined in the musculus longissimus dorsi, and muscle samples were collected for water-holding capacity and tenderness analyses. Lambs from experimental group were characterized by higher (P ≤ 0.05) body weights after rearing, pre-slaughter starvation and transport. There were no significant differences in haematological parameters induced by the group or BST, except neutrophils to lymphocytes ratio (P ≤ 0.05 and P ≤ 0.01, respectively). Significant differences in cortisol levels were not observed between groups, but significant variations in this parameter were noted between each BST (P ≤ 0.01). In both groups, glucose levels increased significantly at BST 3 relative to BST 1 and BST 2; however in EG group the values were higher at each stage in comparison with CG. No significant differences in colour parameters such as L* (lightness) and b* (yellowness) were observed between CG and EG groups. The meat of EG lambs was characterized by lower (P ≤ 0.05) values of pHu, expressed juice area, shear force and colour parameter a* (redness). The results show that β-glucan reduces the negative impact of pre-slaughter stress on the final product quality.