High taurine concentrations negatively effect stallion spermatozoa parameters in vitro

Over the past decades natural substances are widely used in the maintaining of spermatozoa viability. The target of present study was to evaluate the effect of various taurine concentrations on stallion spermatozoa during 37°C cultivation. Fresh semen was collected from 10 breeding stallions. The experimental groups were supplemented with six different concentration of taurine (in mg/ml): A – 2.5, B – 5, C – 7.5, D – 10, E – 15, F – 20 and compared to control (CON – 0). Spermatozoa motility was assessed using the Computer Assisted Semen Analyzer (CASA) system in 6 time periods (0, 1, 2, 3, 4 and 5 hours). The MTT test was used for detection of viability. For measuring antioxidant activity FRAP and TOS methods were used. Significantly negative effect was observed in the samples with the highest concentration of taurine (20 mg/ml). Spermatozoa viability was not significantly affected in analysed concentrations of taurine. Significant higher antioxidant activity was detected in the sample with the highest taurine concentration. Data clearly showed negative effects of high taurine concentrations on stallion spermatozoa.