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Sperm Subpopulations (sperm + subpopulation)
Selected AbstractsMultivariate Cluster Analysis Regression Procedures as Tools to Identify Motile Sperm Subpopulations in Rabbit Semen and to Predict Semen Fertility and Litter SizeREPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2007A Quintero-Moreno Contents Computerized motility analysis (CASA) shows that four separate subpopulations of spermatozoa with different motility characteristics co-exist in rabbit ejaculates. There were significant (p < 0.01) differences in the distribution of these subpopulations among separate genetic lines, total sperm abnormalities and the percentage of altered acrosomes. Furthermore, logistic and linear multivariate regressions among several parameters of rabbit semen quality analysis were tested for use as predictive tools for the fertilizing ability of a specific artificial insemination semen sample. Logistic regression analysis rendered two mathematical, significant (p < 0.01) models: one between sperm viability and conception rate and the other between total sperm abnormalities and conception rate. Multiple linear regression analyses also yielded some significant relationships between both fertility (p < 0.001) and litter size (p < 0.05), with respect to some semen characteristics. Our results support the hypothesis that the predictive in vivo fertility use of the standard rabbit semen quality analysis coupled with a CASA determination could be reasonably achieved by applying linear and logistic regression analyses among several parameters of rabbit semen quality analysis. [source] Interaction between leucocytes and human spermatozoa influencing reactive oxygen intermediates releaseINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 2 2004Monika Fr Summary The relationship between the presence of white blood cells (WBCs) and the fertilizing potential of human semen is still an open question. It is well known that the presence of leucocytes in human semen can be related to the production of reactive oxygen intermediates (ROI). Semen samples were obtained from 15 normozoospermic men and leucocytes were isolated from heparinized blood drawn from 15 volunteers. Lucigenin and luminol-mediated chemiluminescence assays were used to determine reactive oxygen species (ROS) generation by non-activated or activated leucocytes through 12-myristate-13-acetate or N-formyl-methionyl-leucyl-phenyalanine (FMLP) before the addition of spermatozoa isolated by swim-up or Percoll procedures. All spermatozoal fractions used in this study were characterized by defining their motility, morphology and viability. The levels of ROS formation by non-activated as well as stimulated leucocytes were significantly decreased after addition of swim-up separated spermatozoa (p < 0.01). The ability to inhibit the basal chemiluminescence was of lower degree for spermatozoa isolated from 90% Percoll fractions than for swim-up sperm. However, addition of sperm cells from 47% Percoll fraction was found to increase both lucigenin and luminol signals. Moreover, the determined ROI levels changed depending on the type of inducing factor used for oxidative burst. Then, spermatozoa selected by swim-up procedure although with only slightly higher viability and morphology than sperm obtained from 90% Percoll fraction clearly exhibited much higher capacity to inhibit ROI secretion by receptor-stimulated leucocytes (FMLP-activation) than Percoll fractionated sperm. Such results may indicate that within normal semen may exist sperm subpopulations with different biochemical mechanisms controlling the interaction between spermatozoa and contaminating leucocytes. When ROI levels contained in normozoospermic semen are dependent on the WBCs activation, it seems that spermatozoa with preserved normal functional competence are able to defend themselves against leucocytes-derived ROI. Also for normozoospermic ejaculates, swim-up sperm may improve semen antioxidant characteristics when comparing with Percoll (90%) separated sperm. It may help for optimal sperm preparation when assisting to infertility treatment. [source] Effects of Cryopreservation on Bull Spermatozoa Distribution in Morphometrically Distinct SubpopulationsREPRODUCTION IN DOMESTIC ANIMALS, Issue 4 2007J Rubio-Guillén Contents Assisted sperm morphometry analysis (ASMA) was used in this study to determine the effects of cryopreservation on bull spermatozoa distribution in morphometrically distinct subpopulations. Ejaculates were collected from five bulls and were divided. One portion was diluted at 30°C in a skim milk,egg yolk medium, containing glycerol. A microscope slide was prepared from single extended sperm samples prior to freezing. The remainder of each sample was frozen in nitrogen vapours. After thawing, sperm smears were prepared as described above. All slides were air dried and stained with Hemacolor. The sperm-head dimensions for a minimum of 200 sperm heads were analysed from each sample by means of the Sperm-Class Analyser® (SCA), and the mean measurements recorded. Our results showed that applying the ASMA technology and multivariate cluster analyses, it was possible to determine that three separate subpopulations of spermatozoa with different morphometric characteristics coexist in bull ejaculates (large, average and small spermatozoa). The mean values of each sperm head dimension among the three subpopulations of spermatozoa were significantly different (p < 0.001). Besides, there were significant (p < 0.001) differences in the distribution of these three sperm subpopulations between fresh and thawed samples. Thus, the percentage of representation of the subpopulation that includes those spermatozoa whose dimensions are the biggest, decreased from 52.06% in extended fresh samples to 15.51% in the thawed ones. Contrarily, the percent of representation of the subpopulation containing the smallest spermatozoa, increased from 8.70% in extended fresh samples to 34.04% in the thawed ones. In conclusion, the present study confirms the heterogeneity of sperm head dimensions in bull semen, heterogeneity that vary through the cryopreservation procedure. [source] Effects of Constant, 9 and 16-h Light Cycles on Sperm Quality, Semen Storage Ability and Motile Sperm Subpopulations Structure of Boar SemenREPRODUCTION IN DOMESTIC ANIMALS, Issue 5 2006MM Rivera Contents This study was performed to test the effect that two separate, daily, constant-light regimes of both 9 and 16 h could have on the main parameters of boar-semen quality analysis, as well as on the motile sperm subpopulations structure and the ability of its conservation at 16°C. Results show that both luminous regimes have slight, specific effects on the main parameters of boar-semen quality analysis, as well as on the motile sperm subpopulations structure. Furthermore, the conservation ability at 16°C of boar semen was not significantly different between both photoperiods. When a temporal study was performed, results showed that semen quality and motility parameter changes were stabilized at nearly constant values from the second month of the study to the last month in both luminous regimes, indicating a rapid light-related effect on testicular function. Our results indicate that light regimes oscillating from 9 h daily to 16 h daily are of little importance in the control of boar-semen quality in a farming environment. [source] OC2 Seasonality Affects on Sperm Motility Kinematic Parameters of Murciano-Granadina BucksREPRODUCTION IN DOMESTIC ANIMALS, Issue 2006D Abdelwahab Four Murciano-Granadina (M-G) bucks were used to study the effect of season (autumn and spring) on semen motility kinematic parameters. Ejaculates (n = 31/season) were collected twice weekly with an artificial vagina and diluted with Tris-based extender (1 : 10). Average path velocity (VAP) and linearity (LIN) were evaluated using a Computer-Assisted Semen Analysis (CASA system). A FASTCLUS procedure was applied to separate spermatozoa into subpopulations based on their motility characteristics. The mean values of both motility kinematic parameters were significantly (p < 0.05) higher in spring than in autumn. Four different motile sperm subpopulations (SP) were identified. In autumn, SP 1 (with a frequency of 17.1%) showed a VAP of 41.5 ,m/s and a LIN of 38.3%. SP 2 (37.2%) a VAP of 70.2 ,m/s and a LIN of 46.1% SP 3 (19.1%) a VAP of 93.3 ,m/s and a LIN of 31.6%. Finally, SP 4 (26.6%) a VAP of 111.8 ,m/s and a LIN of 67.2%. In spring, SP 1 (21.1%) a VAP of 46.3 ,m/s and a LIN of 50.1%. SP 2 (39.6%) a VAP of 77.0 ,m/s and a LIN of 68.6%. SP 3 (17%) a VAP of 87.8 ,m/s and a LIN of 40.2%. Finally, SP 4 (22.3%) a VAP of 112.3 ,m/s and a LIN of 70.4%. In conclusion, the season of ejaculate collection has a significant effect on sperm motility kinematic parameters of M-G bucks. [source] | ||||||||||