اثرعصاره اتانولی گیاه مرزنجوش بر فراسنجه های کیفی و غلظت مالون دی آلدهید اسپرم منجمد یخ گشایی شده گاو هلشتاین

Background: various stages of processing, storage and cryopreservation of semen, reduce frozen-thawed sperm quality due to physiological and chemical stress on the sperm membrane, decreasing sperm quality. to overcome this problem, utilization of antioxidants can play an important role. objectives: the purpose of this study is to investigate the effect of origanum vulgare extract as a natural antioxidant on microscopic and biochemical parameters of frozen-thawed holstein bull sperms. methods: in this study, semen samples were collected from three mature holstein bulls twice a week using artificial vagina and ejaculates were pooled in order to eliminate the individual effects of bulls. different levels of origanum vulgare ethanol extract (2, 4, 8, 12, 16 and 20 ml in 100 ml of diluents solution) were added to diluents based on egg yolk-citrate. following cooling and equilibration stage of semen samples, the samples were exposed to nitrogen vapor to be frozen and stored in liquid nitrogen until evaluation. motility, viability, membrane integrity and the lipid peroxidation parameters of the samples were evaluated after thawing, using casa system, eosin-nigrosin staining, hypo osmotic swelling test and measuring malondialdehyde concentration, respectively. results: the addition of 4 ml/dl of origanum vulgare extract improved motility, viability and plasma membrane integrity parameters of spermatozoa significantly and reduced the lipid peroxidation as well compared to the control group, following freeze-thawing process (p < 0/05). conclusions: our study confirms the positive effectiveness of adding 4 ml/dl origanum vulgare on quality of cryopreserved bull sperm.