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Thawed Spermatozoa (thawed + spermatozoa)
Selected AbstractsEffect of Ram Age on Structural and Functional Competence of Frozen,Thawed Spermatozoa in Dairy SheepREPRODUCTION IN DOMESTIC ANIMALS, Issue 4 2010AG Lymberopoulos Contents The objectives of this study were to investigate the influence of ram age on structural and functional competence of frozen,thawed spermatozoa and to test the hypothesis that increasing number of sperm bound to the zona pellucida in vitro was associated with decreasing in vivo fertility of frozen semen. Rams were allocated into two groups. Each group consisted of five rams aged either 1,2 years (young) or 4,5 years (mature). Three successive ejaculates were collected from each ram using an artificial vagina. Only ejaculates of , 2.5 × 109 sperm/ml and 80% sperm progressive motility were pooled per ram, diluted with Bioxcell® medium and frozen in 0.25 ml straws. The end points of post-thawing semen evaluation were computer-assisted cell motility analysis, sperm capacitation (chlortetracycline assay), simultaneous assessment of plasma membrane integrity, mitochondrial membrane potential and condensation status of nucleus, per-cell analysis of lipid peroxidation using C11-BODIPY581/591, sperm-hemizona binding (HZB) ability and sperm fertility after laparoscopic insemination of ewes (n = 114) in the progestagen-synchronized oestrus. The results showed that mature rams had significantly lower values of sperm hyperactivated motility and peroxidized sperm, higher percentages of live non-capacitated sperm and sperm cells with intact plasma membrane, functional mitochondria and condensed chromatin, as well as, greater lambing rate and ewe prolificacy. Sperm HZB binding ability was higher (p < 0.05) for young than for mature rams. Significant correlations were found between number of spermatozoa bound to the zona pellucida and semen fertility (r = ,0.63 to ,0.71). In conclusion, mature rams have better semen quality and in vivo fertility than young rams. Cryocapacitation can be involved in decreasing ram semen fertility as evidenced by the high number of spermatozoa bound to the zona pellucida in vitro. [source] Cryopreservation of YamúBrycon siebenthalae MiltJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2004Pablo E. Cruz-Casallas The yamúBrycon siebenthalae is an endemic fish of the Orinoco river basin, but wild stocks are decreasing because of the disruption of their habitat. We evaluated a protocol for the cryopreservation of yamú sperm to contribute to the preservation of this endangered genetic resource. Milt was mixed with a cryoprotectant medium (5.5% glucose, 12% egg yolk, and 5%, 10%, or 15% dimethyl sulfoxide - DMSO) in a ratio 1:4 (milt:medium), stored in 0.5-mL French straws, frozen in nitrogen liquid vapor (-76 C), then immersed and stored in liquid nitrogen for 10 d or 12 mo. Motility of thawed spermatozoa was higher (P < 0.001) in 10% DMSO medium than 5% DMSO or 15% DMSO mediums; but lower than the control (P < 0.001). With sperm cryopreserved, the highest level of fertilization was achieved with 10% DMSO (P < 0.001) after 10 d or 12 mo of cryopreservation. Fertilization of eggs inseminated with 6.4 × 109 spermatozoa per g of eggs was higher (P <0.05) than with 1.6 × 109 spermatozoa per g of eggs. There was no difference (P > 0.05) in fertilization between insemination doses of 3.2 × 109 and 6.4 × 109 spermatozoa per g of eggs. Cryopreservation of yamu milt can be performed successfully with a simple medium combined with 10% of DMSO as cryoprotectant. The highest level of fertility was achieved using between 3 × 109 and 6 × 109 spermatozoa per g of fresh eggs. [source] Effect of Ram Age on Structural and Functional Competence of Frozen,Thawed Spermatozoa in Dairy SheepREPRODUCTION IN DOMESTIC ANIMALS, Issue 4 2010AG Lymberopoulos Contents The objectives of this study were to investigate the influence of ram age on structural and functional competence of frozen,thawed spermatozoa and to test the hypothesis that increasing number of sperm bound to the zona pellucida in vitro was associated with decreasing in vivo fertility of frozen semen. Rams were allocated into two groups. Each group consisted of five rams aged either 1,2 years (young) or 4,5 years (mature). Three successive ejaculates were collected from each ram using an artificial vagina. Only ejaculates of , 2.5 × 109 sperm/ml and 80% sperm progressive motility were pooled per ram, diluted with Bioxcell® medium and frozen in 0.25 ml straws. The end points of post-thawing semen evaluation were computer-assisted cell motility analysis, sperm capacitation (chlortetracycline assay), simultaneous assessment of plasma membrane integrity, mitochondrial membrane potential and condensation status of nucleus, per-cell analysis of lipid peroxidation using C11-BODIPY581/591, sperm-hemizona binding (HZB) ability and sperm fertility after laparoscopic insemination of ewes (n = 114) in the progestagen-synchronized oestrus. The results showed that mature rams had significantly lower values of sperm hyperactivated motility and peroxidized sperm, higher percentages of live non-capacitated sperm and sperm cells with intact plasma membrane, functional mitochondria and condensed chromatin, as well as, greater lambing rate and ewe prolificacy. Sperm HZB binding ability was higher (p < 0.05) for young than for mature rams. Significant correlations were found between number of spermatozoa bound to the zona pellucida and semen fertility (r = ,0.63 to ,0.71). In conclusion, mature rams have better semen quality and in vivo fertility than young rams. Cryocapacitation can be involved in decreasing ram semen fertility as evidenced by the high number of spermatozoa bound to the zona pellucida in vitro. [source] Autologous Whole Ram Seminal Plasma and its Vesicle-free Fraction Improve Motility Characteristics and Membrane Status but not In Vivo Fertility of Frozen,Thawed Ram SpermatozoaREPRODUCTION IN DOMESTIC ANIMALS, Issue 5 2007R El-Hajj Ghaoui Contents Motility characteristics (assessed subjectively and with computer-assisted semen analysis) and membrane status (after staining with chlortetracycline) of washed and non-washed frozen,thawed ram spermatozoa were evaluated after incubation in buffer and buffer containing autologous whole seminal plasma or one of its two fractions: the pellet of membrane vesicles obtained by ultracentrifugation (and used at three times normal protein concentration) or the vesicle-free supernatant fraction. Whole seminal plasma and supernatant, but not membrane vesicles, improved the motility characteristics of spermatozoa after 3 and 6 h of post-thaw incubation compared with the control buffer. Resuspension and incubation with whole seminal plasma, supernatant or membrane vesicles lowered the proportion of acrosome-reacted frozen,thawed spermatozoa compared with the control buffer. Unwashed frozen,thawed semen from three rams, incubated with autologous whole seminal plasma or its fractions and inseminated using cervical or intrauterine artificial insemination, had no effect on pregnancy rates of ewes in synchronized oestrus. However, fertility was higher after laparoscopic than cervical insemination (44.9 vs 12.3%, p < 0.001). In conclusion, resuspension and incubation of frozen,thawed ram spermatozoa in autologous whole seminal plasma or its vesicle-free supernatant fraction improved their motility characteristics and, with membrane vesicles, membrane status, but these benefits were not reflected in improved fertility after cervical or intrauterine insemination. [source] Effect of freezing,thawing on the expression of mannose-ligand receptors on human spermatozoa: the impact on sperm capacitation and acrosome reactionANDROLOGIA, Issue 5 2001H. Yavetz Summary., The aim of this study was to evaluate the change in the expression of mannose-ligand receptors following a freezing,thawing procedure, in order to assess its impact on sperm capacitation and acrosome reaction. Twenty semen samples were obtained from fertile donors. Sperm samples were divided into two equal volumes. One aliquot was cryopreserved and the other aliquot was incubated at 32 °C. After 2 h the frozen sample was thawed and both samples were further incubated at 32 °C to allow capacitation. Mannose receptors were examined following 4 and 22 h of incubation using a mannosylated-BSA-FITC probe. The expression of mannose-ligand receptors on the sperm plasma membrane was determined according to the fluorescence pattern: pattern I represents pre-capacitation, pattern II represents capacitated spermatozoa and pattern III represents acrosome-reacted spermatozoa. After 4 h incubation in capacitating medium, the percentages of patterns I, II and III were 90, 7 and 3% for fresh spermatozoa and 89, 8 and 3% for frozen,thawed spermatozoa, respectively (P > 0.05). Following 22 h of incubation, the percentages of patterns I, II and III were 84, 11 and 5 for fresh spermatozoa and 83, 11 and 6% for frozen,thawed spermatozoa, respectively (not significant at P > 0.05). The percentages of patterns II and III in fresh and frozen,thawed spermatozoa were increased by the same magnitude with longer incubation in the capacitating conditions. It was concluded that the freezing,thawing procedure for human spermatozoa does not affect the expression of mannose-ligand receptors and the dynamics of sperm pre-fertilization processes. [source] | ||||||||||