冷冻保存对长白猪精液品质与DNA甲基化的影响

为研究冷冻保存对猪精液品质及其分子机制的影响,本实验选用15头长白猪精液,检测冷冻保存与常温保存后的精液品质以及相关抗氧化水平,并基于上述精液品质与抗氧化性能的测定,挑选常温与冷冻保存精液表型值极端的3头个体分别检测精液中铜锌超氧化物歧化酶基因(CuZn-SOD)、锰超氧化物歧化酶基因(Mn-SOD)和过氧化氢酶基因(...     

纳米化红景天多糖对猪精液冷冻效果的影响

在冷冻稀释液中分别添加分数为1％、5％、10％、15％、20％的纳米化红景天多糖（Nonomaterialsrhodiolasa—chalinensispolysaccaride,NRSP）溶液,以添加6mg／L红景天多糖（Rhodiolasachalinensispolysaccaride,RSP）为对照组,不添加RSP为空白组,检测其对猪冷冻精子活力、顶体完整率、质膜完整率等生理结构指标,以及精子抗氧化能力的影响。结果表明,添加体积分数为15％NRSP组的精子活力（0．69）、顶体完整率（51．42％）、质膜完整率（25．95％）均高于其他组,并显著高于空白组（P〈0．05）。此外添加15％NRSP组的解冻后直线运动精子百分比（46．33％）要显著高于其他各组（P〈0．05）;添加6mg／LRSP组丙二醛（MDA）浓度最低（10．83±0．39）／2mol／L,并且显著低于空白组（31．85土1．36）μmol／L,（P〈0．05）,但与15％的NRSP组（11．60±0．42）μmol／L无显著差异（P〉0．05）。添加20％的RNSP组超氧化物歧化酶（SOD）活力最高（343．05-＋-19．64）μ／mgprot,显著高于其他添加组（P〈0．05）。精子活力、顶体完整率、质膜完整率之间存在显著的正相关关系（P〈0．05）,而精子活力和顶体完整性与MDA浓度呈显著负相关（P〈0．05）,与SOD活力呈显著正相关（P〈0．05）,质膜完整率与两者含量相关性不显著（P〉0．05）。     

香菇多糖对湖羊精液冷冻保存品质的影响

试验旨在研究香菇多糖和甘油的不同浓度组合对湖羊精液冷冻保存效果的影响。将香菇多糖以0(L0)、0.5(L0.5)、1(L1)、4(L4)mg/mL与3%甘油(G3)、5%甘油(G5)分别进行组合,成为L0G3、L0.5G3、L1G3、L4G3、L0G5、L0.5G5、L1G5和L4G5。将这些组合分别添加到基础冷冻稀释液中,并加入精液冷冻保存,在解冻后检测精子活力、顶体完整率、总抗氧化能力(T-AOC),测定总谷胱甘肽(T-GSH)含量和丙二醛(MDA)含量。结果显示：基础冷冻稀释液中添加0.5 mg/mL香菇多糖,可显著提高了湖羊精子冷冻-解冻后精子活力(P<0.01)、顶体完整率(P<0.05)、T-GSH含量(P<0.01)和T-AOC(P<0.01),有效抑制MDA的生成(P<0.01),且L0.5G5组比L0.5G3组保存效果更好(P<0.01);而添加高浓度香菇多糖不利于湖羊精液冷冻保存。本试验中香菇多糖和甘油在提高湖羊精液冷冻保存效果方面不存在协同作用。这些结果表明,在稀释液中添加0.5 mg/mL香菇多糖和5%甘油可有效提高湖羊精液的...     

黄芪多糖对猪精液冷冻保存效果的影响

为了评价黄芪多糖（Astragalus polysaccharides）对外来公猪精液冷冻保存的影响情况,为猪精液冷冻稀释液配方的改良提供理论依据,试验采集美系长白、大约克与杜洛克3种公猪的精液,用添加不同浓度（0、0.01%、0.02%、0.03%、0.04%、0.05%、0.06%）黄芪多糖的冷冻稀释液稀释,0.25 mL塑料细管分装并冷冻,测定解冻后精子活力、畸形率及顶体完整率,并进行相同浓度3种公猪之间和同种公猪不同浓度之间的比较。结果表明,在相同黄芪多糖浓度下,仅杜洛克公猪冻后精子顶体完整率在不添加黄芪多糖时显著高于大约克公猪（P<0.05）,其余均无显著差异（P>0.05）;每种公猪的最佳黄芪多糖添加浓度均为0.04%,在该浓度下精液冻后质量均显著优于对照组（P<0.05）;各种公猪最佳黄芪多糖添加浓度下的精液冻后质量指标之间均无显著差异（P>0.05）。总之,稀释液中添加0.04%黄芪多糖在长白、大约克与杜洛克3种公猪的精液冷冻都可以取得较好的效果。     

水蛭素对猪精液冻后质量的影响

试验用含不同浓度(0、0.02%、0.04%、0.06%、0.08%、0.10%、0.12%)水蛭素的稀释液稀释美系公猪精液,并以0.25mL细管分装冷冻。结果显示:(1)水蛭素浓度为0、0.02%时在冻后精子畸形率或水蛭素浓度为0、0.12%时冻后精子顶体完整率上存在明显的品种效应(P0.05);(2)3种公猪各浓度组(除大约克和杜洛克公猪0.02%浓度组外)冻后精子活力均显著高于对照组(P0.05),且均在浓度为0.08%时最高;除了长白公猪0.02%浓度组冻后精子畸形率显著低于对照组(P0.05)外,3种公猪各浓度组与对照组差异均不显著(P0.05);大约克公猪各试验组、杜洛克公猪0.08%浓度组及长白公猪0.02%、0.06%及0.08%浓度组冻后精子顶体完整率显著高于对照组(P0.05),且均在浓度为0.08%时最高,长白及杜洛克公猪其他试验组与对照组差异均不显著(P0.05)。结果表明,适宜浓度的水蛭素可以显著提高猪精液冻后质量,效果最好的浓度为0.08%。     

哺乳动物生殖细胞冷冻保存对其DNA甲基化影响的研究进展

哺乳动物生殖细胞和胚胎冷冻保存在辅助生殖技术中得到了广泛的应用,同时在保存物种的多样性方面发挥着巨大的作用。但是,冷冻引起的DNA甲基化对其印记基因缺陷性疾病的发生和后代生理功能的差异会有很大的影响。作者就冷冻保存技术对配子（精子和卵子）和胚胎的DNA甲基化的影响以及冷冻引起的DNA甲基化对后代的影响进行了综述,以期对配子的冷冻保存和辅助生殖技术的发展提供参考。     

家蚕基因组DNA甲基化分析

DNA甲基化在生物的基因表达调控与发育调节过程中具有重要作用。应用甲基化敏感扩增多态性(MSAP)技术对7个家蚕保存品种的胞嘧啶甲基化模式和程度进行评估。在所能检测的CCGG序列中,至少有8.6%~10.9%的胞嘧啶发生了甲基化;12对引物共获得1 156条扩增带,其中376条在品种间呈多态性,多态性比例为32.5%。结果显示:家蚕基因组可检测到DNA甲基化,各品种间的甲基化模式存在差异,CCGG序列中胞嘧啶外部甲基化(10.9%)高于内部甲基化(8.6%)。     

奶牛性控冷冻精液品质和转染外源DNA的特点

本研究分析了奶牛性控冻精与普通冻精解冻后精液品质和转染外源DNA的特点。奶牛性控冻精与普通冻精解冻后,分别检测精液品质和精子超微结构,并与地高辛标记的线性化pEGFP-N1质粒共育转染,用免疫组化的方法检测精子转染外源DNA的效率。结果表明:性控冻精与普通冻精相比,有效精子数少(P0.01),精子活力、顶体完整率差(P0.05);2组精子超微结构都出现一定程度的顶体破裂、脱落等形态变化;2组精子都具有自动结合和转运外源DNA的能力,性控冻精转染率极显著高于普通冻精(P0.01),分别为(11.34%±2.41%)和(7.30%±2.14%)。     

黄芩多糖对长白猪精液冷冻保存效果的研究

本研究旨在探讨不同浓度的黄芩多糖添加方案对猪冷冻精液保存效果的影响。猪冷冻处理的精液共6组,分别为空白对照组和添加不同浓度黄芩多糖的试验组（在冷冻稀释液中分别添加0.2、0.4、0.6、0.8、1.0g/L黄芩多糖）,对冷冻-复苏的精液进行精子活力及相关运动参数、精子质膜完整性、顶体完整率等指标检测。结果表明：与空白对照组相比,添加0.4 g/L的黄芩多糖对冷冻-复苏后的精子直线速度、曲线速度、平均路径速度、顶体完整率、DNA完整率和精子抗氧化酶活性均有提高（P<0.05）。0.6 g/L黄芩多糖组精液冷冻复苏后精子的运动参数、顶体完整率及抗氧化酶活性与0.4 g/L黄芩多糖组无显著差异。此外,0.8 g/L黄岑多糖组的质膜完整率及直线性高于其他组（P<0.05）。综上所述,添加不同浓度的黄芩多糖均可提高猪冷冻精液品质,其中提高猪冷冻精液保存质量的最适添加量是0.4 g/L。     

猪0.5 mL细管冻精不同解冻方法精子质量的研究

利用计算机辅助精子分析系统(CASA)结合顶体完整率(NAR)的检查,研究了长白猪0.5 m L细管冻精4种解冻程序后精液的质量,综合评价不同解冻方法。结果表明:1)精子冷冻-解冻后在曲线速度(VCL)、直线速度(VSL)、平均路径速度(VAP)、直线性(LIN)、前向性(STR)、鞭打频率(BCF)以及A+B类精子比例的检测性状上降低,差异极显著(P0.01);精子头侧摆幅度(ALH)也显著减小(P0.05),活率(Motile rate)变化差异不显著(P0.05);2)四组解冻程序中,38℃20 s解冻组的活率(Motile rate,MR)、VSL、VCL、STR、A+B精子比例指标均极显著(P0.01)优于42℃20 s、50℃15 s、62℃5 s解冻组,VAP、LIN与NAR差异不显著(P0.05);3)Topsis综合评价的结果表明38℃20 s组在孵育2 h、4 h、6 h之后检测性状优于其他解冻组。由此推论,虽然解冻后精子在运动参数发生较大变化,但是38℃20 s的解冻效果优于其他解冻条件。     

Effect of dilution temperature on boar semen quality

As boar semen is very sensitive to cold shock and changes in temperature during semen processing can have a profound impact on semen quality, the effect of the extender temperature at the time of dilution was investigated in a two-step dilution protocol for boar semen being processed for liquid storage. Fifteen boars of different breeds and ages from a commercial artificial insemination centre were included. One ejaculate per boar was collected and processed with Beltsville Thawing Solution semen extender. Each ejaculate was diluted (1 : 1) at 30 °C, and subsequently, the samples were diluted (30 × 10(6) sperm/ml) with either preheated extender [29.3 °C ± 0.2 °C, group A (GA)] or extender at room temperature [22.7 °C ± 0.6 °C, group B (GB)]. Samples were transported to the Faculty of Veterinary Medicine (University of Ghent, Belgium) in two isotherm boxes (one per group), stored at 17 °C and investigated for three consecutive days (D0 to D2). At D0, D1 and D2, motility parameters [computer-assisted semen analysis (CASA)] and the per cent of sperm with intact membrane (% IM) by eosin nigrosin staining were evaluated. At D0 and D2, the % of sperm with intact acrosome (% IA) was studied by Pisum sativum agglutinin staining. The average temperature of the 1 : 1 dilution was 29.4 °C ± 1.1 °C immediately after extender addition. No significant differences were found between groups for per cent motility [79.3 ± 9.0 for GA and 81.1 ± 9.2 for GB (p = 0.372)], % progressive motility [56.5 ± 13.3 for GA and 58.4 ± 13.8 for GB (p = 0.737)] or any CASA parameter. No differences were found for % IM [85.1 ± 10.7 and 84.5 ± 3.8 for GA and GB, respectively (p = 0.761)] and % IA [72.2 ± 9.4 for GA and 68.3 ± 16.6 for GB (p = 0.792)]. In conclusion, when a two-step dilution is performed, preheating the extender for the second dilution to match the semen temperature did not result in better semen quality compared to a dilution at a moderate room temperature.     

Dynamics of sperm DNA fragmentation in raw boar semen and fertility

The aims were to evaluate sperm DNA fragmentation (SDF) in boars through the dispersion of their chromatin in raw semen samples, quantifying the extent of SDF, and to assess dynamic aspects of sperm DNA damage after incubation to obtain the rate of sperm DNA fragmentation (rSDF) under thermal conditions similar to the uterus (37°C) over a period of up to 24 hr and to correlate the reproductive outcome of the sows with the SDF of the boars at ejaculation. The study was performed on a pig‐breeding farm in southern Uruguay. Sixty‐one ejaculates from five of the most frequently used hybrid boars were evaluated. Semen was collected weekly from each of the boars, using the gloved‐hand technique and discarding the jelly‐like fraction of the ejaculate. Fresh semen was kept in a water bath at 37°C and protected from light, and was thereafter processed with Sperm‐Sus‐Halomax^® to evaluate SDF. The smears for time 0 (T0) were made on farm, and thereafter smears were made at the laboratory at 4 hr of obtaining the semen (T4), then every 2 hr (T6, T8, T10, T12) and a final fixation at 24 hr (T24). Differences in SDF were observed among exposure times for all boars (p < .05), but not between T10 and T12 (p = .7751) nor T4 and T24 (p = .9113). In none of the T24 samples, sperm heads could be seen with chromatin dispersion halos. Furthermore, there were differences among boars when comparing sperm rSDF (p < .05). Farrowing rate was not affected by SDF at T0 (r = .38, p = .75), nor was litter size (r = .16, p = .70). With the present experimental conditions, we have not been able to show a relationship between sperm DNA fragmentation at ejaculation and reproductive performance. However, this could be a result of the low number of ejaculates and boars used.     

脱霉剂对种公猪精液品质的影响

饲料霉变及霉菌毒素严重影响饲料工业和畜牧业生产。本试验以种公猪作为试验对象,在公猪日粮中添加G1和G2脱霉剂,试验开始后每周对公猪精液品质进行品质检测,G2见效要比G1快;两种脱霉剂使用后对采精量、每次射精精子总数、精子活力均有所提高,精子畸形率也有下降。综上所述,这两种脱霉剂均可有效提高霉菌毒素引起的公猪生殖性能抑制,从而提高公猪的精液品质,G2效果要更佳。     

The incidence of agglutination and its influence on sperm quality and fertility of boar semen

The aim of this study was to examine the incidence of sperm agglutinations and their relationships with sperm quality and fertility. Semen samples of 40 boars of an AI-station were investigated. Nineteen of the 40 investigated boars showed a constantly low (< 10% agglutinated sperm), 3 an intermediate (10-20%) and 6 boars a high level (> 20%) of agglutination in raw semen. The degree of agglutination in sperm samples of 12 boars varied distinctly during the investigation period. During summer more (P < 0.05) agglutinated sperm were observed (11.0 +/- 11.6%) than during winter (6.2 +/- 7.3%). There was no association between bacterial contamination and incidence of agglutinations (P > 0.05). After dilution in extender the percentage of agglutinated sperm decreased from 6.2 +/- 7.3% to 1.1 +/- 1.4% (P < 0.0001). Twenty-four hours after dilution the percentage of progressively motile sperm was 7.4% lower (P < 0.05) in ejaculates with an initially high degree of agglutination (> 20% agglutinated sperm) compared to samples with an initially low degree of agglutinated sperm (< 10%). Plasma membrane integrity, mitochondrial membrane potential, acrosome reaction and chromatin structure were independent (P > 0.05) from the level of agglutination. Fertility data did not differ (P > 0.05) between boars with low and high numbers of agglutinated sperm in raw semen. The results show that there are individual, ejaculatory and seasonal variations in the incidence and degree of agglutination. Agglutinations have a negative effect on motility of sperm and disappear to a large extent after dilution in sperm extender. They have no negative consequences on fertility.     

Assessment of sperm quality traits in relation to fertility in boar semen

Background

Several studies have been published where sperm plasma membrane integrity correlated to fertility. In this study we describe a simple fluorometer-based assay where we monitored the fluorescence intensity of artificially membrane-ruptured spermatozoa with a fixed time staining with fluorescent DNA dyes.

Methods

Membrane-impermeant fluorescent dyes Hoechst 33258 (H258) and propidium iodide (PI) were used to measure the fluorescence of the nucleus in artificially membrane ruptured spermatozoa and membrane-permeant dye Hoechst 33342 (H342) was used to measure fluorescence of intact spermatozoa. The concentration of spermatozoa in insemination doses varied from 31.2 × 10⁶/ml to 50 × 10⁶/ml and the average value was 35 × 10⁶/ml. Each boar was represented by three consecutive ejaculates, collected at weekly intervals. Nonreturn rate within 60 days of first insemination (NR %) and litter size (total number of piglets born) of multiparous farrowings were used as fertility measures.

Results

Sperm fluorescence intensity of H258 and H342, but not the fluorescence intensity of PI-stained spermatozoa correlated significantly with the litter size of multiparous farrowings, values being r = - 0.68 (P < 0.01) for H258, r = - 0.69 (P < 0.01) for H342 and r = - 0.38, (P = 0.11) for PI.

Conclusions

The increase in fluorescence values of membrane-ruptured H258 and unruptured H342-stained spermatozoa in boar AI doses can be associated with smaller litter size after AI. This finding indicates that the fluorescence properties of the sperm nucleus could be used to select for AI doses with greater fertilizing potential.     

青蒿对夏季公猪精液品质的影响

本试验旨在研究饲粮中添加青蒿对夏季公猪精液品质的影响.选择20头配种丹系长白公猪,按照年龄、质量等随机分成试验1、2、3组和对照组,对照组饲喂基础日粮,试验1、2、3组在饲喂同等日粮基础上分别添加青蒿粉10、20、30 g/头·d,测定其采精量、精子密度、精子活率.结果表明,20 g/头·d为最佳添加量.     

绵羊精液稀释液中添加PUFA对冷冻精液品质的影响

通过在绵羊精液冷冻稀释液葡3-3稀释液(葡萄糖-柠檬酸盐-卵黄)中添加富含多不饱和脂肪酸(PUFA)的深海鱼油,研究其对绵羊精子冷冻-解冻过程的作用.