Introduction: One of the freezing semen disadvantages is increasing of free radicals leading
to enhanced sperm membrane peroxidation then consequently causes lowered semen fertility
after thawing. Some plants bearing high level of natural antioxidants can help to decrease
semen peroxidation. The objective of the present study is to evaluate the ability of rosemary
extract to protect ram sperm from freeze-thaw damages.
Materials & Methods: In this study, ejaculates were collected from 4 Zandi rams. Semen
samples were pooled after each sampling. Experimental treatment included five levels of
rosemary aqueous extract (0, 2.5, 5, 7.5 and 10 percent). Then samples were frozen and
transferred to liquid nitrogen tanks for three weeks. After thawing sperm quality parameters
including total and progressive motility, abnormalities, sperm membrane integrity and MDA
production were evaluated.
Results: The results showed that rosemary extract significantly improved total and progressive
motility, sperm membrane integrity and viability, and decreased sperm abnormalities and MDA
production at levels of 5 and 7.5 percent (p<0.05).
Conclusion: According to the obtained data, adding specific levels of rosemary extract in the
diluent will have a protective effect in the freezing-thawing process of Zandi rams sperm.