During last years, many experiments reported from the antioxidant activity of Echinacea purpurea extract. In general, antioxidant activity of E. purpurea extract is high then of other medicinal and aromatic herbs which could be ascribed to the polyphenolic components, such as flavonoids phenolic acids or phenolic diterpenes. The objective of the present study was to evaluate the ability of the E. purpurea extract to protect ram sperm cells from freeze- thaw damages. The sperm cells separated and recovered in the laboratory by flushing from ten ram testes, and cryopreserved in tris- citrate solution supplemented with various concentration of E. extract (5-10 and 20 mg/L). The motility and velocity parameters, plasma membrane functionality, viability, response to hypo osmotic swelling test (HOST) and malonaldehide (MDA) concentration were as sperm cell characteristics assessed. The results indicate that the addition of 10 mg E. purpurea extract to the extender presents significantly an enhancement of total motility (81.34±1.2%), progressive motility (50.25±0.14 %), average path velocity (VAP, 57±0.36, µm/s), as compared to the other treatments. Regarding the plasma membrane functionality, the extender supplemented with 20 mg E. purpurea extract increased significantly (90.04±2.4%) as compared to extenders containing 5 (81.06±1.9%) and 10 mg (82.04±1.6%) E. purpurea and control (81.79±1.3%). No significant differences were observed for the percentage of acrosome integrity. between the treatments. Additionally, the obtain results showed that MDA concentration was significantly lower in extenders added 10 mg (0.0055±1.55 nmol/ml) and 20 mg E. purpurea (0.0057±1.55 nmol/ml) treatments as compared to 5 mg E. purpurea (0.0078±1.55 nmol/ml) and control (0.0080±1.55 nmol/ml), respectively. Our data imply that supplementation of E. purpurea extract in an appropriate level has a beneficial effect on post- thawed ram sperm cell parameters without any deleterious effect on sperm
