Objective:To evaluate the effect of adding different values of polymyxin B (PMB) to bull semen on various motility parameters of post-thawed semen such as total motility, progressive motility and velocity parameters u...Objective:To evaluate the effect of adding different values of polymyxin B (PMB) to bull semen on various motility parameters of post-thawed semen such as total motility, progressive motility and velocity parameters using kinetic parameters of sperm by Computer Assisted Sperm Analysis.Methods: Gram negative bacteria release lipopolysaccharide, which induces the apoptotic pathway. Antibiotics are added to semen in order to prevent bacterial contaminations in bovine semen. These antibiotics kill the bacteria especially gram negative bacteria. Therefore, their endotoxins are released during bacteriolysis and bind to the head region and midpiece of sperm. PMB is a bactericidal antibiotic against multidrug resistant gram-negative bacteria and is able to neutralize the toxic effects of the released endotoxin. This study was performed on 3-year old Taleshi bulls. Results:The results showed both positive and negative significant effects of PMB on semen quality. Total motility and progressive motility were significantly increased (P<0.0001) by 100 μg per mL of PMB (55.2% and 48.8% respectively) against the control groups (43.5% and 37.7%, respectively). Moreover, they were significantly decreased (P<0.0001) by 1000 μg per mL of PMB (35.2% and 28.8% respectively) against the control groups (43.5% and 37.7% respectively) in above-mentioned parameters. In Computer Assisted Semen Analyzer, parameter VAP was significantly decreased (P<0.04) in 1000 μg (69.6 μm/s) against the control group (78.7 μm/s). Finally, using PMB in processing cryopreserved bull semen is advised, but before using it, the rate of endotoxins must be measured.Conclusions: We advise using PMB after measuring endotoxin concentration;In vitro,in vivoand in field fertilization, adding other sperm evaluation factors such as acrosomal integrity, DNA integrity, mitochondrial function to PMB treated semen.展开更多
Objective:To reveal the effects of 9-cis retinoic acid (RA) on cortical granules (CGs) migration andin vitro embryo production (IVP) rate in meiosisⅡvitrified bovine oocyte. Methods:Followingin vitro maturation (IVM)...Objective:To reveal the effects of 9-cis retinoic acid (RA) on cortical granules (CGs) migration andin vitro embryo production (IVP) rate in meiosisⅡvitrified bovine oocyte. Methods:Followingin vitro maturation (IVM) in a medium containing 5 nM of 9-cis-RA, 60 oocytes were vitrified and then thawed. Then, half of them were evaluated for CGs migration and the other half were used for in vitro fertilization and IVP (on day 3). In addition, the other 60 oocytes were considered as the control group, which did not receive RA in IVM medium. The data were presented to one way analysis of variance (ANOVA) and Duncan's test.Results:Results showed that IVP rate (4-8 cells embryos) was significantly (P<0.05) higher than the control group when RA had been added to IVM medium. Furthermore, the presence of RA in IVM medium improved the rate and mode of CGs migration so that the rate of oocytes that had completed CGs migration in the group, which had received RA, was significantly higher than the control group.Conclusions:This study shows that presence of RA in IVM medium enhances the developmental competence and CGs distribution of meiosisⅡvitrified bovine oocyte. Therefore, adding RA in IVM medium can decrease the ultrastructural changes during vitrification and can improve the efficiency of bovine oocyte vitrification.展开更多
文摘Objective:To evaluate the effect of adding different values of polymyxin B (PMB) to bull semen on various motility parameters of post-thawed semen such as total motility, progressive motility and velocity parameters using kinetic parameters of sperm by Computer Assisted Sperm Analysis.Methods: Gram negative bacteria release lipopolysaccharide, which induces the apoptotic pathway. Antibiotics are added to semen in order to prevent bacterial contaminations in bovine semen. These antibiotics kill the bacteria especially gram negative bacteria. Therefore, their endotoxins are released during bacteriolysis and bind to the head region and midpiece of sperm. PMB is a bactericidal antibiotic against multidrug resistant gram-negative bacteria and is able to neutralize the toxic effects of the released endotoxin. This study was performed on 3-year old Taleshi bulls. Results:The results showed both positive and negative significant effects of PMB on semen quality. Total motility and progressive motility were significantly increased (P<0.0001) by 100 μg per mL of PMB (55.2% and 48.8% respectively) against the control groups (43.5% and 37.7%, respectively). Moreover, they were significantly decreased (P<0.0001) by 1000 μg per mL of PMB (35.2% and 28.8% respectively) against the control groups (43.5% and 37.7% respectively) in above-mentioned parameters. In Computer Assisted Semen Analyzer, parameter VAP was significantly decreased (P<0.04) in 1000 μg (69.6 μm/s) against the control group (78.7 μm/s). Finally, using PMB in processing cryopreserved bull semen is advised, but before using it, the rate of endotoxins must be measured.Conclusions: We advise using PMB after measuring endotoxin concentration;In vitro,in vivoand in field fertilization, adding other sperm evaluation factors such as acrosomal integrity, DNA integrity, mitochondrial function to PMB treated semen.
文摘Objective:To reveal the effects of 9-cis retinoic acid (RA) on cortical granules (CGs) migration andin vitro embryo production (IVP) rate in meiosisⅡvitrified bovine oocyte. Methods:Followingin vitro maturation (IVM) in a medium containing 5 nM of 9-cis-RA, 60 oocytes were vitrified and then thawed. Then, half of them were evaluated for CGs migration and the other half were used for in vitro fertilization and IVP (on day 3). In addition, the other 60 oocytes were considered as the control group, which did not receive RA in IVM medium. The data were presented to one way analysis of variance (ANOVA) and Duncan's test.Results:Results showed that IVP rate (4-8 cells embryos) was significantly (P<0.05) higher than the control group when RA had been added to IVM medium. Furthermore, the presence of RA in IVM medium improved the rate and mode of CGs migration so that the rate of oocytes that had completed CGs migration in the group, which had received RA, was significantly higher than the control group.Conclusions:This study shows that presence of RA in IVM medium enhances the developmental competence and CGs distribution of meiosisⅡvitrified bovine oocyte. Therefore, adding RA in IVM medium can decrease the ultrastructural changes during vitrification and can improve the efficiency of bovine oocyte vitrification.
