(P-435) Post-Thaw Characteristics of Ram Spermatozoa and Activity of Antioxidant Enzymes after Supplementing Semen Extender with Mn2+-, Zn2+- or Cu2+ -Nanosuccinate
Associate Professor University of Guelph Guelph, Ontario, Canada
Abstract Authors: Pawel M. Bartlewski1, olga Sharan2, Vasyl Stefanyk2, Dmytro Ostapiv3, Mykola Sharan3
1. Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
2. Stepan Gzhytskyi National University of Veterinary Medicine and Biotechnologies in Lviv, Ukraine
3. Institute of Animal Biology NAAS, Lviv, Ukraine
Abstract Text: The main goal of this experiment was to determine the effects of Mn2+-, Zn2+- or Cu2+-nanosuccinate added to semen extender on ram semen characteristics and activity of antioxidant enzymes after thawing. This study utilized six clinically healthy Texel rams aged 2-4 years during seasonal anestrus (April-May). Ejaculates (n=36; 6 per ram) collected into an artificial vagina were evaluated for volume, sperm concentration and motility, and then divided into isovolumetric control and experimental fractions (n=10 per ejaculate). Control semen was diluted with lactose-yolk-tris-citrate-glycerin medium (LYTCGM) and nanosuccinates (Mn2+- and Zn2+-nanosuccinate: 2.5, 5.0 and 7.5 μg/l; Cu2+-nanosuccinate: 1.25, 2.5 and 3.75 μg/l) were added to LYTCGM in experimental semen samples. Extended semen was loaded into 0.25-ml straws (64 x 107 spermatozoa/ml), equilibrated for 2.5 h and then frozen in liquid nitrogen. Post-thaw sperm motility was determined with Computer Assisted Semen Analysis (CASA) and the activity of antioxidant enzymes (superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT)) was measured with a spectrophotometric technique. The addition of an intermediate dose of Mn2+- and Zn2+-nanosuccinate to LYTCGM was associated with a significant increase in ram sperm progressive motility, and the lowest and intermediate dose of both nanosuccinates improved sperm motion kinetics/velocity parameters. Moreover, Mn2+- and Zn2+-nanosuccinates at a dose of 5.0 μg/l, consistently decreased (P< 0.05) SOD activity and boosted (P< 0.05) GPX and CAT activity in ram semen samples after thawing. Alternatively, the addition of Cu2+-nanosuccinate to LYTCGM (highest dose) significantly reduced the progressive motility and velocity of thawed ram spermatozoa. increased the percentage of sperm with acrosomal/head defects and seminal SOD activity, and depressed CAT (highest dose) and GPX (all doses) activity. In summary, the addition of Mn2+- and Zn2+-nanosuccinate to semen extender appeared to have beneficial effects on sperm motility/motion kinetics and structural integrity, whereas Cu2+-nanosuccinate generally had debilitating effects on the post-thaw semen characteristics in rams.