In Vitro effect of different levels ‎of peppermint (Mentha piperital) ‎extract on semen quality ‎parameters in Arabi ram

The aim of this study was to investigate the effect of different levels of peppermint extract on semen quality of Arabi rams. Semen was collected from 12 Arabi rams weekly for 8 weeks and immediately mixed, and then were divided into 5 parts and received zero, 50, 100, 150 and 200 μl/ml of peppermint extract. At different storage times of diluted semen containing treatments (zero, 24, 48 and 72 hours) in liquid condition, semen quality parameters were evaluated. Immediately after sperm collection, the lowest total motility and sperm viability belonged to the level of 200 peppermint extract (P<0.05). At 24 hours, levels 150 and 200 of extract increased the rate of morphological abnormalities of sperms. At this time, the lowest level of sperm plasma membrane integrity was related to the level of 200 peppermint extracts (P<0.05). 48 hours after sperm storage, the highest total motility, viability and plasma membrane integrity of sperms were belonged to the control group (P<0.05). 72 hours after semen storage, no statistically significant differences were found among treatments for all sperm quality parameters. At this time, the highest concentration of malondialdehyde (MDA) in seminal plasma was related to the level of 100 μl/ml peppermint extract (P<0.05). In general, by adding different levels of peppermint extract to the diluent and maintaining the diluted semen of the Arabi ram in a liquid state at 5°C, the concentrations used of peppermint extract not only did not improve the qualitative parameters of the sperm, it also had a devastating effect.