Effects of Two Amino Acids On Motion Parameters of Freeze-Thawed Stallion Spermatozoa

Artificial insemination of mares with frozenthawed semen has greatly improved in the last decade. However, because of cryodamage to sperm cells, its fertility rate is low. some amino acids are known to be involve in protecting animal cells against hypothermia, and perform cryoprotective action in freezing media . In this study, effects of two amino acids, glutamine and proline, as supplements of freezing extender were studied during cryopreservation of stallion spermatozoa. Ten ejaculates from five fertilestallions collected by artificial vagina, were frozen in basal medium as control (E1) and basal medium containing 3mM (E2), 30mM (E3) and 60mM proline (E4), 5mM (E5) and 50mM glutamine (E6) and 3mM proline plus 5mM glutamine (E7). The CASA were performed after thawing. E2 increased progressive motility (p<0.001), motile spermatozoa (p> 0.05), and values of VCL, VAP, MAD, ALH, BCF and STR compared to control extender, while E3 led to a less motile and progressive motile sperm. E3, E4 and E6 was found to provide lower mean values of LIN, WOB and STR than control group, whereas E5 enhanced LIN and decreased MAD value significantly (p<0.05). There was no difference between CASA parameters of E7 and the control. The higher motility of stallion spermatozoa in diluent containing 3mM proline may allow for the more efficient use of frozenthawed stallion semen for insemination, and could contribute to the improvement of semen cryopreservation in the world horse industry.

Keywords:

Glutamine , Proline , Post-Thawed , Stallion Sperm , Motion Parameters