The aim of the present study was to evaluate effect of 3 levels of butylated hydroxytoluene （BHT） supplemented in extender for fighting bull semen. Ejaculates were obtained from 10 healthy fighting bulls by artifici...The aim of the present study was to evaluate effect of 3 levels of butylated hydroxytoluene （BHT） supplemented in extender for fighting bull semen. Ejaculates were obtained from 10 healthy fighting bulls by artificial vagina. Semen with motility of more than 70% was included in the experiment. Tris-fructose-glycerol-egg yolk extender containing 0, 1, 3 and 7 mM BHT was used to dilute semen to final concentration of 200 × 10^6 cells/ml. Diluted semen was frozen in 0.25 mL straws and frozen semen was thawed in a 37 ℃ water bath for 15 sec before being evaluated at 0 and 1 hour. Sperm motility at 0 and 1 hour after thawing did not differ among groups tested （ranged 47.86-53.57 and 21.79-24.29 respectively）. At 0 hour after thawing, percentage of live sperm of 3 mM BHT （37.39% ± 2.91%） was lower than those of 0 and 1 mM BHT （43.71%± 2.76% and 41.46% ±2.59% respectively, P 〈 0.05） but not different from 7 mM BHT （40.89%± 2.50%）. The effect was more significant at 1 hour after thawing and 3 mM BHT （32.07% ± 2.45%） suppressed live cells more than other concentrations （ranged 35.07%-37.46%, P 〈 0.05）. At 0 hour after thawing, percentage of membrane integrity （hypo-osmotic swelling test） was not affected by BHT concentration （ranged 23.89%-28.54%）. However, at 1 hour after thawing, percentage of membrane integrity of 3 mM BHT （19.75% ± 1.41%） was lower that of 7 mM BHT （23.29% ± 1.88%, P 〈 0.05） but not different from those of 0 and 1 mM BHT （20.32% ±1.81% and 22.07% ± 2.27% respectively）. No significant effect was found on percentage of abnormal sperm. There was no effect of BHT supplementation in extender on most of the Hamilton-thorn motility analyser parameters. It may be concluded that 3 mM BHT can be harmful to fighting bull spermatozoa and lower concentrmion can be used without detrimental effect. Further study may be needed to verify use of BHT in lower range of concentrations.展开更多
This study aimed to identify and characterize the sperm subpopulations existing in water buffalo semen using a computer assisted sperm analyzer （CASA）, as well as assess the effects of cryopreservation on the sperm ...This study aimed to identify and characterize the sperm subpopulations existing in water buffalo semen using a computer assisted sperm analyzer （CASA）, as well as assess the effects of cryopreservation on the sperm subpopulation structure and evaluate bull variability. The semen of eight Bulgarian Murrah bulls was collected by four times in an interval of one week each. The semen was cryopreserved following a standard protocol and sperm kinematics was assessed. Clustering methods were applied to individual sperms, forming two significantly different （P 〈 0.05） subpopulations （P1 and P2）. Subpopulation P1 represents those spermatozoa that moved most rapidly and progressively （46.29%）, and subpopulation P2 includes spermatozoa with relatively low velocity or poorly motile but with high progressiveness （53.41%）. There was a decline on the population of P1 sperms from fresh （52.52%）, pre-freeze （45.73%） to post-thaw （35.17%） stages and significant difference on the sperm kinematics between P1 and P2. A significant decline in the values of distance, velocity and amplitude of lateral head （ALH） parameters were observed at post-thaw stage, while an increase was observed on trajectory and beat cross frequency （BCF） kinematics. Values of sperm kinematics were also significantly different （P 〈 0.05） among all bulls. The frequency distribution of spermatozoa on both subpopulations P1 and P2 was quite similar for all bulls in pre-freeze and post-thaw stages, but with significant （P 〈 0.05） variability on fresh stage. Bulls with the highest maintained frequency of P1 sperms are denoted as good freezer bulls. In sum, kinematic characterization of water buffalo sperm and clustering into subpopulation enable to identify bulls that are more resistant to cryopreservation and production of quality semen for genetic propagation.展开更多
文摘The aim of the present study was to evaluate effect of 3 levels of butylated hydroxytoluene （BHT） supplemented in extender for fighting bull semen. Ejaculates were obtained from 10 healthy fighting bulls by artificial vagina. Semen with motility of more than 70% was included in the experiment. Tris-fructose-glycerol-egg yolk extender containing 0, 1, 3 and 7 mM BHT was used to dilute semen to final concentration of 200 × 10^6 cells/ml. Diluted semen was frozen in 0.25 mL straws and frozen semen was thawed in a 37 ℃ water bath for 15 sec before being evaluated at 0 and 1 hour. Sperm motility at 0 and 1 hour after thawing did not differ among groups tested （ranged 47.86-53.57 and 21.79-24.29 respectively）. At 0 hour after thawing, percentage of live sperm of 3 mM BHT （37.39% ± 2.91%） was lower than those of 0 and 1 mM BHT （43.71%± 2.76% and 41.46% ±2.59% respectively, P 〈 0.05） but not different from 7 mM BHT （40.89%± 2.50%）. The effect was more significant at 1 hour after thawing and 3 mM BHT （32.07% ± 2.45%） suppressed live cells more than other concentrations （ranged 35.07%-37.46%, P 〈 0.05）. At 0 hour after thawing, percentage of membrane integrity （hypo-osmotic swelling test） was not affected by BHT concentration （ranged 23.89%-28.54%）. However, at 1 hour after thawing, percentage of membrane integrity of 3 mM BHT （19.75% ± 1.41%） was lower that of 7 mM BHT （23.29% ± 1.88%, P 〈 0.05） but not different from those of 0 and 1 mM BHT （20.32% ±1.81% and 22.07% ± 2.27% respectively）. No significant effect was found on percentage of abnormal sperm. There was no effect of BHT supplementation in extender on most of the Hamilton-thorn motility analyser parameters. It may be concluded that 3 mM BHT can be harmful to fighting bull spermatozoa and lower concentrmion can be used without detrimental effect. Further study may be needed to verify use of BHT in lower range of concentrations.
文摘This study aimed to identify and characterize the sperm subpopulations existing in water buffalo semen using a computer assisted sperm analyzer （CASA）, as well as assess the effects of cryopreservation on the sperm subpopulation structure and evaluate bull variability. The semen of eight Bulgarian Murrah bulls was collected by four times in an interval of one week each. The semen was cryopreserved following a standard protocol and sperm kinematics was assessed. Clustering methods were applied to individual sperms, forming two significantly different （P 〈 0.05） subpopulations （P1 and P2）. Subpopulation P1 represents those spermatozoa that moved most rapidly and progressively （46.29%）, and subpopulation P2 includes spermatozoa with relatively low velocity or poorly motile but with high progressiveness （53.41%）. There was a decline on the population of P1 sperms from fresh （52.52%）, pre-freeze （45.73%） to post-thaw （35.17%） stages and significant difference on the sperm kinematics between P1 and P2. A significant decline in the values of distance, velocity and amplitude of lateral head （ALH） parameters were observed at post-thaw stage, while an increase was observed on trajectory and beat cross frequency （BCF） kinematics. Values of sperm kinematics were also significantly different （P 〈 0.05） among all bulls. The frequency distribution of spermatozoa on both subpopulations P1 and P2 was quite similar for all bulls in pre-freeze and post-thaw stages, but with significant （P 〈 0.05） variability on fresh stage. Bulls with the highest maintained frequency of P1 sperms are denoted as good freezer bulls. In sum, kinematic characterization of water buffalo sperm and clustering into subpopulation enable to identify bulls that are more resistant to cryopreservation and production of quality semen for genetic propagation.
