Introduction: Spermatozoa death is accelerated by reactive oxygen species in fresh, refrigerated or frozen/thawed semen. In sheep, antioxidant therapy may alleviate the effects of oxidative stress by favoring antioxidant status. Our aim was to compare the effect of antioxidant therapy on sperm motility in ram semen conserved at both ambient (AT) and refrigeration (RT) temperatures.
Materials and methods: Five rams were daily supplemented with vitamins C 600 mg and E 420 IU during 15 days, while other five were controls. Ejaculates obtained by electro-stimulation were immediately evaluated for volume and sperm concentration. Semen was diluted (Tris/citric acid/fructose medium; 100×106 sperms/ml) and evaluated for motility in a CASA system. Semen was divided and maintained at AT (2126 °C) or RT (56 °C). Motility was subsequently evaluated at 136122436 and 48 h. Results were analyzed by ANOVA and Duncan test.
Results and discussion: No initial differences between vitamins-treated and control rams were observed in semen volume (1.7±0.2 ml), concentration (3.4±0.5×109 sperms/ml) or motility (70.0±5.6%). After 1-h, motility decreased 50% in RT semen, remaining stable until 12-h. At AT, motility decreased slowly until 6-h (56.5±6.3%); at 12-h it was similar to that refrigerated (30.0±5.9%). At 24-h, motility was higher in RT than AT (18.0±4.5 vs 6.2±3.8%, respectively; P=0.05), which continues decreasing rapidly after this time, being almost null at 48-h in both groups. Antioxidants supplementation decreased sperm motility from 1-h until 6-h, without effect in subsequent times. It is concluded that supplementation with antioxidant vitamins impaired semen quality in both AT and RT ram semen.
Funded by Grant FONDECYT 1130181 (CONICYT, Chile).
02 - 04 Sep 2014
World Congress of Reproductive Biology