论文部分内容阅读
Objective: To examine the effect of different concentrations of trehalose or sucrose (50 or 100 or 200 mM) on post-thawed quality of bull semen, cryo-preserved in Tris-citric acid-egg yolk-fructose (TCYF). Methods:Semen samples were diluted in TCYF extender, TCYF +trehalose (50, 100 and 150 mM/L) or TCYF+sucrose (50, 100 and 150 mM/L) to ensure 60 million motile spermatozoa mL-1, cooled slowly up to 5℃ and equilibrated for 4 h. Semen was packed into 0.25 mL polyvinyl French straws. The straws were placed horizontally on a rack and frozen in a vapor 4 cm above liquid nitrogen (LN2) for 10 minutes then dipped in liquid LN2. Frozen straws were thawed at 37℃ for 1 min. The parameters studied were sperm motility, sperm viability, sperm abnormality, sperm membrane integrity (HOST), percent of normal intact acrosome and DNA fragmentation. Results:The output data demonstrated that addition of 50–100 mM of trehalose or sucrose/L TCYF after chilling at 5℃ had significantly (P<0.0001) ameliorated motility, membrane integrity, viability, abnormal morphology, and acrosome integrity %compared to control diluted semen while 50 mM of trehalose/L, and 50-100 mM of sucrose/L to TCYF diluent had significantly (P<0.0001) improved after thawing motility (43.00,% 45.00%and 41.00%, respectively), membrane integrity (67.40%, 67.80%and 69.40%, respectively), life sperm % (70.20%, 69.40%and 71.40%respectively), and acrosome integrity percentages (56.40%, 58.80%and 55.80%respectively) compared to the control tris-base diluent, while diminishing the abnormal sperm morphology (6.20, 3.80 and 3.80 respectively) and DNA fragmentation (3.60%, 3.80%and 3.80%respectively). Besides, the addition of 100 mM of trehalose/L to tris-base diluent has also a promising effect when added to the tris-base diluent concing the above parameters. Conclusion:It is finally concluded that the addition of 50- 100 mM trehalose or sucrose/L to TCYF have a beneficial effect in chilling diluted bull semen, while the use of 50 mM trehalose or 50–100 mM sucrose had their benefits on freezing-thawing of extended semen.