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1.
性控技术可以加速优良种畜的繁育速度,有效发挥母畜的繁殖潜力,为乳用动物提供母畜,为肉用动物提供公畜。将雄性动物精液分离不但可以提高后代质量,而且可提高繁殖效率。动物性控精液的分离作为动物遗传育种的重要组成部分,为畜牧业发展起到了重要作用。本文综述了流式细胞仪分离精液的研究进展及精液纯度评价方法,以期为新方法的探索提供参考。  相似文献   
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This study compared the postthaw semen parameters of stallions with high and low body condition score (BCS) and evaluated associations between body morphometric parameters and postthaw semen parameters. Twenty stallions were split into Low BCS (BCS<7, n = 11) and High BCS (BCS ≥7, n = 9) groups, and underwent a complete morphometric analysis (e.g., neck scores and circumference, crest neck height, body weight, and height), and subcutaneous body fat thickness (SFT) at the tail head, withers, shoulders, and retroperitoneal space. A fasted oral sugar test (OST) was conducted on all stallions. One ejaculate from each stallion was frozen with a commercial egg yolk-based extender. Postthaw sperm motility parameters, plasma membrane integrity, mitochondrial membrane potential, hydrogen peroxide and intracellular superoxide production, and lipid peroxidation were analyzed for all stallions. The circumference at 25% and 50% of the neck’s length were larger for High-BCS stallions (P < .05). There were no differences between groups for the neck crest height (P > .05). Stallions with High BCS had greater SFT at the tail head than stallions with Low BCS (P < .05); however, there were no differences between groups in the SFT at the shoulders and withers (P > .05). All stallions had resting blood glucose below the cutoff for equine metabolic syndrome. There were no differences between groups for resting glucose concentrations or for a peak at 30 or 60 minutes after initiation of the OST (P > .05). There were no differences in sperm parameters between groups (P > .05). Collectively, the findings of the present study suggest that High BCS or Low BCS in the presence of normal OST do not explain post-thaw semen parameters.  相似文献   
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Alternative sources of lipoproteins in semen extenders could replace animal by-products. We hypothesized that: (1) post-thaw semen parameters and fertility would not be different in coconut water (CW)–treated samples compared with egg yolk (EY)–treated samples and (2) the use of an oxygen scavenger (Oxyrase) would improve post-thaw sperm motility and membrane integrity and decrease lipid peroxidation. Experiment 1: three ejaculates each from five stallions were split into four treatments: EY, CW, egg yolk with Oxyrase, and coconut water with Oxyrase. Computer-assisted sperm analysis measured progressive and total motility, velocity, and linearity. Membrane integrity, apoptosis, and lipid peroxidation were evaluated using propidium iodide, annexin, and BODIPY fluorescent probes, respectively. Samples were cryopreserved, stored in liquid nitrogen, and then thawed to 37°C and analyzed again. Experiment 2: one ejaculate was divided into two aliquots and cryopreserved using either CW or EY. In a crossover design, 12 mares were bred on two consecutive cycles with either EY or CW. Pregnancy evaluations were at 14-day gestation. No differences were detected in sperm parameters between CW and EY (P > .05). Oxyrase did not improve sperm motility parameters in post-thaw samples, nor did it show protective effects for viability or against membrane damage (P > .05). More mares became pregnant using CW than EY (11/12 vs. 6/12, respectively; P = .013). Use of CW is a viable alternative to animal-based products in the cryopreservation of stallion semen.  相似文献   
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Spermatozoa are highly specialized cells that are sensitive to environmental factors such as temperature and redox state. Hydrogen peroxide (H2O2) is a reactive oxygen species, and its presence is often associated with a decline in sperm function. The aim of this study was to evaluate the effect of H2O2 and heat stress on DNA damage, membrane integrity, and motility of stallion spermatozoa. Spermatozoa from three light-horse stallions were subjected to thermal stress, treatment with H2O2, or a combination of both. Treatments were organized using a 2 × 2 factorial design consisting of heat stress (control, 41°C) and potential oxidative stress (control, 50 μM H2O2) for 1 hour. The experiments were repeated independently on all stallions. Primary motility parameters were measured using a computer-assisted sperm analysis, whereas DNA damage was assessed using the TUNEL assay. To evaluate membrane integrity, an amine reactive dye was utilized. DNA and membrane integrity were simultaneously assessed in the same flow cytometry assay. Sperm incubated at 41°C were observed to have decreased motility (76.2% vs. 66.6%; P < .05) but not progressive motility (39.2% vs. 25.6%), membrane damaged (30.8% vs. 37.4%), or DNA damage (19.7% vs. 17.3%). Interestingly, when compared to control, treatments with H2O2 had decreased DNA damage (19.7% vs. 7.1%; P < .05), but did not affect any other parameter. Although our experiment demonstrated a favorable effect of 50 μM H2O2 on DNA damage, further studies need to be conducted to confirm these findings and to clarify any possible signaling mechanisms.  相似文献   
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Cryopreservation of boar semen is still considered suboptimal due to lower fertility as compared with fresh samples when glycerol, a permeating cryoprotectant, is used. Trehalose is a non-permeable cryoprotectant and nonreducing disaccharide known to stabilize proteins and biologic membranes. The aim of this study was to evaluate the cryosurvival and in vitro penetrability of boar spermatozoa when glycerol was replaced with trehalose in a freezing extender. Ejaculated Berkshire semen samples were diluted in egg yolk-based freezing extender containing glycerol (100 mM) or trehalose (0, 50, 100, 150, 200 and 250 mM) and cryopreserved using a straw freezing procedure. Thawed samples were analyzed for motility, viability, mitochondrial membrane potential (MMP), and acrosome integrity. In experiment 2, penetrability of spermatozoa cryopreserved with 100 mM glycerol or trehalose was examined. Replacement of cryoprotectant glycerol (100 mM) with trehalose had no effect on sperm viability, but replacing it with 100 mM trehalose improved motility, MMP and acrosome integrity significantly. Sperm motility and MMP were considerably higher in 100 mM trehalose, whereas the acrosome integrity was substantially higher in 100–250 mM trehalose. The in vitro penetration rate was also significantly higher in spermatozoa cryopreserved with trehalose (61.3%) than in those cryopreserved with glycerol (43.6%). In conclusion, 100 mM non-permeable trehalose can be used to replace glycerol, a permeating cryoprotectant, for maintenance of better post-thaw quality of boar spermatozoa.  相似文献   
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This study evaluated measures of sperm quality in relation to fertility achieved with fresh semen or semen cooled and stored. Semen from 1 stallion was collected and processed to provide 3 treatments: group 1 received fresh semen; group 2 received cooled semen containing 50% seminal plasma (SP) stored for 4 days; and group 3 received cooled semen containing 50% SP stored for 1 day, then centrifuged and resuspended in fresh extender containing 10% SP on days 1 to 3. Inseminates were evaluated for sperm motion characteristics and the percentage of sperm with intact membranes (SMI). Mares (n = 34) in estrus were treated with an ovulation-inducing drug and inseminated with 100 million membrane-intact sperm on the following day. Pregnancy status was determined via transrectal ultrasonography 2 weeks after ovulation. The mean percentage of SMI was higher in group 1 (81%, initial) than in group 2 (74%, day 4) or group 3 (74%, day 4) (P < .05). The median percentages of total sperm motility differed among the groups (77%, 5%, 59% for groups 1, 2, and 3 respectively; P < .05). Median values for the percentages of progressively motile sperm and curvilinear velocity for group 1 (55%, 216 μm/s) and 3 (37%, 186 μm/s) were higher than for group 2 (1%, 73 μm/s) (P < .05). Pregnancy rates did not differ among groups (5 of 11, 45% in group 1; 5 of 11, 45% in group 2; and 7 of 12, 58%, in group 3; P = .77). These data suggest that, at least for this stallion, sperm membrane integrity may be a more valuable means of assessing potential fertility of cooled-stored semen than sperm motion characteristics.  相似文献   
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本研究探讨了还原剂β-巯基乙醇(β-ME)、二硫苏糖醇(DTT)及谷胱甘肽(GSH)预处理水牛精子对水牛ICSI介导转基因(ICSI-mediated gene transfer,ICSI-Tr)效果的影响。结果显示,β-ME、DTT和GSH预处理水牛精子对提高ICSI介导转基因的效果不显著(p〉0.05),但GSH能显著提高2原核(PN)的形成率(p〈0.05)。  相似文献   
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邓明捷  赵琎  杨明洁  张田  王敏康 《安徽农业科学》2011,39(18):11088-11092
[目的]探讨芸豆凝集素(PHA)受体在小鼠精子和卵母细胞上的分布及作用。[方法]应用异硫氰酸荧光素(FITC)标记的芸豆凝集素作为分子探针,确定其PHA受体在小鼠精子和卵母细胞上的分布。通过不同浓度PHA处理精子和卵母细胞,研究PHA预处理对精子获能和顶体反应,以及对卵母细胞FITC—PHA染色的影响。l结果]PHA受体主要表达于小鼠精子整个尾部区域和顶体反应后的头部质膜,2mg/mlPHA预处理有抑制顶体反应的作用;卵母细胞透明带和细胞膜都有PHA受体的存在。不同浓度PHA处理卵母细胞对其透明带阿FTIC—PHA染色影响不大,但对其细胞膜染色有较大影响,且不同浓度之间差异明显。[结论]芸豆凝集素受体是小鼠精子和卵母细胞受体的重要组成部分,且在精卵质膜融合过程中发挥重要作用。  相似文献   
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