This study has been conducted in college of agriculture – University of Baghdad with cooperation of High institute of Infertility Diagnosis Assisted Technology - Al-Nahrain University and Ministry of Agriculture – Agricultural Research Center. Five Awassi Rams were exposed to study semen samples were diluted in tris extender, tris, cooled slowly up to 5 C˚ and equilibration period for 2 h. Semen was packed into 0.25 ml cryovial, The cryovial were placer horizontally on a rack and frozen in a vapor 4 cm above liquid nitrogen vapor (LN2) for 15 min or 7.5 Min then dipped in liquid LN2.
Frozen cryovial were thawed media at 37C for 1 min. The results of this study There were a high significant (p>0.01) increasing of exposing samples to nitrogen vapor technique for the period of 15min in for the studying characteristics semen in comparison with 7.5min of exposing samples to nitrogen vapor. The adding concentrations of omega-3 0.5, 1% to thawing solution due to enhancing in studying characteristics in comparison with concentrations of omega-3 0%. There was a significant effect of the interaction between the exposing samples to nitrogen vapor technique and concentration of omega-3 in thawing solution for the studying characteristics, additionally, no significant differences between 0.5 and 1% concentration of omega-3 in 15min period of nitrogen vapor exposing was observed to the property of motility, membrane integrity, DNA fragmentation and mitochondrial apoptosis. As conclusion from the previous above using of nitrogen vapor exposing technique for period of 15min and using of omega-3 concentration 0.5, 1% due to an enhancing in the studying characteristics semen.