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1.
本文阐述了精液冷冻保存的细胞反应原理,指出冷冻保护剂甘油对精液保存具有利弊效应,提出精子膜脂组成的差异使得不同品种的精子对冷冻损伤的易感性不同。雌性生殖道解剖结构的品种差异,精子形态,精子运行机制的细微差异,人工授精时间及精子的运行能力,采精方式等因素对人工授精的效果有决定性作用。研究精子质膜的生物学特性可解决低活力精子的问题,然而这并不能解决冷冻后精子质量的个体差异。对精细胞基因组的研究可以找出这些个体的遗传差异。因此,冷冻精子和精原细胞(用于细胞外注射)的差异已经成为完整基因组问题。  相似文献   

2.
精子在冷冻保存过程中会受到不可逆的冷冻损伤或者部分功能改变,因此精子的冷冻保存是一个大挑战。虽然从广义上讲,物种之间的精子冷冻保存是非常相似的,但是每个物种的精子有着各自的特殊性,迫使研究人员不断优化冷冻保护剂和操作程序以更好地适应其特殊性。对家兔精液冷冻保存的概况进行了阐述,讨论了家兔精液冷冻保存的研究概况以及影响冷冻精液和人工授精的因素。  相似文献   

3.
牛的冻精稀释液是精液冷冻保存和人工授精最关键的环节。本文进行了两个方面的试验研究,一是把各个地区生产实践中应用的不同冷冻稀释液配方,进行综合筛选和比较;二是对没有条件冷冻精子的养殖场进行精子保鲜的稀释液配方进行综合筛选和比较。结果显示,当冷冻保存精液时,选择配方2为最佳配方;常温保存时选择配方2、3、4均可。  相似文献   

4.
为了研究冷冻保存对绵羊精子谷胱甘肽还原酶(GR)活性的影响,提高绵羊冷冻精液的品质,试验采用DTNB比色法对冷冻保存前后精液、精子和精清中GR活性进行研究。结果表明:与冷冻前比较,冷冻保存后精液、精子和精清中GR活性均极显著升高(P0.01)。说明超低温冷冻过程会刺激精子的应激反应,导致绵羊精子中GR活性显著提升。  相似文献   

5.
山羊精液冷冻保存不仅可以使品种改良的速度加快,加速育种进程,而且在山羊人工授精、生物安全等方面有着重要的意义。文章综述了山羊精液冷冻保存稀释液中抗氧化剂、冷冻保护剂和冷冻解冻程序对山羊精子冻融后品质的影响以及山羊冻精技术在人工授精中的应用,以期为山羊冻精技术进一步发展提供理论依据,同时也为提高优秀种质资源利用率奠定基础。  相似文献   

6.
为了研究冷冻保存对绵羊精液肌酸激酶(CK)活性的影响,提高绵羊冷冻精液的品质,试验采用生物素双抗体夹心酶联免疫吸附法(ELISA)对冷冻保存前后绵羊精液、精子和精清中CK活性进行研究。结果表明:与冷冻前比较,冷冻保存后绵羊精液、精子CK活性极显著降低(P0.01),而精清中CK活性显著升高(P0.05)。说明冷冻保存对绵羊精子CK活性影响严重。  相似文献   

7.
牛精液冷冻保存技术研究进展   总被引:1,自引:0,他引:1  
牛精液冷冻保存的应用促进了我国牛人工授精技术的发展,通过冷冻保存可以延长精液保存时间,扩大良种公牛精液的使用范围,提高种用价值,加速品种的育成和改良步伐。本文从牛冷冻精液稀释液的成分,卵黄稀释液与无动物源性稀释液的发展,冷冻保护剂对精子冷冻效果的影响,抗氧化剂和抗生素在牛精液冷冻保存中的应用等方面进行了综述,旨在为今后的牛精液冷冻保存研究工作提供一定的参考。  相似文献   

8.
精液冷冻保存技术是山羊繁育体系的重要组成部分,可以有效保存优质种质资源并加速山羊育种工作进程。山羊精子在冷冻过程中会受到氧化应激、冷应激等不利因素的损伤,导致山羊精子解冻后质量和人工授精受胎率较低,大大限制了山羊冻精的应用。因此,本文综述了近年来在山羊冷冻保存稀释液中添加抗氧化剂、糖类、脂肪酸等添加剂对山羊精子解冻后质量的影响,以期为山羊冷冻精液研究提供理论参考。  相似文献   

9.
冷冻造成精子的结构和功能变化是导致繁殖率低的根本原因。笔者通过对比试验,检测精液冷冻后对羊繁殖率的影响。用假阴道法采集3只~4只公羊精液,用Tris稀释液作为冷冻保存液,用TALP作为解冻液,比较精液冷冻前后活力;对同期发情处理的羊只进行鲜精和冻精人工授精,比较两者在受胎率上的变化。结果表明,冷冻前后精子活力分别为74.43%和46.25%,受胎率分别为83.33%和47.06%,说明超低温冷冻通过影响精子内部结构,显著降低了精子活力和受胎率。  相似文献   

10.
为了研究冷冻保存对绵羊精液过氧化氢酶(CAT)活性的影响,从而提高绵羊冷冻精液的品质,试验采用CAT比色法对冷冻保存前后绵羊精子和精清中CAT活性进行了研究。结果表明:与冷冻前相比,冷冻保存后绵羊精子中CAT活性极显著降低(P0.01);精清中CAT活性极显著升高(P0.01)。说明冷冻保存对绵羊精子和精清中CAT的活性造成了很大影响;冷冻后精子活率与精子CAT活性呈显著正相关(r=0.887,P0.05),冷冻前精子活率与精子CAT活性呈极显著正相关(r=0.987,P0.01)。说明绵羊精子中CAT的活性与精子活率密切相关,可作为绵羊精液品质评价的参考指标。  相似文献   

11.
The aim of this study was to investigate the effect of platelet activating factor (PAF) on the quality characteristics of cryopreserved canine spermatozoa. Cryopreserved semen of 5 mixed-breed dogs was treated with different concentrations of exogenous PAF (1 x 10(-3) M, 1 x 10(-4) M, 1 x 10(-5) M and 1 x 10(-6) M) and examined at different time intervals (0, 30, 60 and 120 min). Cryopreserved semen treated without PAF was used as the control. Sperm quality was evaluated for motility (computer-assisted semen analysis, CASA), mitochondrial function (JC-1/PI assay) and plasma membrane integrity (SYBR-14/PI assay and Hoechst 33258). Also, ATP content of spermatozoa was determined using a bioluminescence assay. Treatment of cryopreserved semen with 1 x 10(-3) M PAF at 120 min of incubation resulted in significantly higher total sperm motility compared with the control. It was observed that PAF-improved total sperm motility was concurrent with enhanced sperm motility patterns after treatment of cryopreserved semen. Treatment of cryopreserved semen with PAF did not improve either sperm mitochondrial function or plasma membrane integrity, as monitored by different fluorescent membrane markers. Furthermore, ATP content of cryopreserved spermatozoa was significantly higher when PAF was used at a concentration of 1 x 10(-3) M compared with the control and other PAF treatments, regardless of the incubation time. The findings of this study indicated that treatment with 1 x 10(-3) M PAF at 120 min of incubation rendered better quality of cryopreserved canine semen, which was associated with improved sperm motility parameters and ATP content. It can be suggested that exogenous PAF addition is beneficial as a supplement for canine semen extender used for cryopreservation.  相似文献   

12.
目的 精液冷冻保存作为人工授精不可或缺的一个技术环节,对优质畜禽种群的繁衍和保存有着至关重要的意义。目前,因精液冻存时冻存液成分、冷冻方法和外部氧化应激等因素影响,导致冻存精液品质不一。蜂王浆(RJ)已被证明能提高动物精液品质,蜂王浆主蛋白(MRJPs)作为RJ主要生物活性成分物质,具有多种生物活性和抗氧化能力。方法 为提高冻存精子品质,本研究开展了在公牛精液冻存液中添加不同浓度(0 g/25 mL、0.01 g/25 mL、0.02 g/25 mL、0.03 g/25 mL、0.04 g/25 mL)的MRJPs冻干粉,对冻存48 h后解冻精子的总活力、前进性活力、畸形率等相关参数进行了观察评估。结果 添加MRJPs呈浓度依赖性方式显著降低精子总活力、快速前进性活力、缓慢前进性活力和直行性活力(P<0.05),而且精子畸形率和精子原地移动活力与对照组相比无显著差异(P> 0.05)。结论 精液冻存液中添加MRJPs会抑制冻存精子活力,因此,对MRJPs能以何种方式提高精液品质的研究还需要进一步开展。  相似文献   

13.
Phosphorylation of tyrosine residues on sperm protein is a known indicator of capacitation and a major intracellular signalling event. There is evidence that sperm cryopreservation promotes tyrosine phosphorylation and is associated with reduced fertility of spermatozoa. Under this study, cryoprotective role of different additives namely taurine, trehalose, catalase and 4-bromophenacyl bromide on buffalo sperm quality was evaluated. Buffalo semen was cryopreserved in tris-based egg yolk extender supplemented with additives like taurine (50 mm) or trehalose (100 mm) or 4-bromophenacyl bromide (200 μm) or catalase (100 U/ml) and used for assessment of levels of tyrosine phosphorylation in frozen-thawed spermatozoa. The results obtained were compared with the level of protein tyrosine phosphorylation of semen cryopreserved in tris-based egg yolk extender without additives. Proteins were extracted from a total number of nine ejaculates from three individual buffalo bulls chosen at random and analysed for tyrosine phospho-proteins using SDS-PAGE followed by immunoblotting. Monoclonal anti-phosphotyrosine antibody (Clone pT-154) was used as primary antibody followed by treatment with HRP-conjugated secondary antibody. Signals were detected on X-ray film using chemiluminescence. Nine proteins (p20, p30, p32, p38, p49, p56, p59, p72 and p86) were found to be tyrosine phosphorylated in cryopreserved spermatozoa. Supplementation of additives significantly (p<0.05) reduced the level of protein tyrosine phosphorylation in spermatozoa. Moreover, this study showed improved (p<0.05) post-thaw motility, viability and membrane integrity of spermatozoa on addition of these additives. The results obtained clearly indicate reduced level of capacitation like changes on supplementation of additives in terms of protein tyrosine phosphorylation.  相似文献   

14.
In mammalian spermatozoa, intracellular calcium plays a major role in sperm functions like motility and capacitation. Cryopreservation-induced modifications to sperm membrane result in an influx of intracellular calcium affecting calcium-dependent intracellular signalling pathways. Intracellular calcium activates adenyl cyclase to produce cAMP that activates phospholipase A(2) (PLA(2) ) and phospholipase C (PLC) generating lysophosphatidyl choline, 1,2-diacylglycerol (DAG) and IP(3) , acting as intracellular secondary messengers required for sperm capacitation. Present study was designed to determine levels of intracellular calcium, cAMP and DAG in fresh and frozen-thawed buffalo spermatozoa cryopreserved in the presence and absence of taurine or trehalose. A total number of nine ejaculates from three randomly chosen buffalo bulls were cryopreserved in Tris-based egg yolk extender and thawed in warm water at 37°C. The cAMP was measured by enzyme immuno assay, and intracellular calcium was quantified using fluorescent dye FURA 2-AM. Total lipid was extracted from spermatozoa, and DAG was estimated using thin layer chromatography followed by spectrophotometric analysis. Intracellular calcium, cAMP and DAG levels in spermatozoa were significantly (p < 0.01) increased following cryopreservation as compared to fresh ejaculate. Addition of taurine or trehalose to the freezing medium significantly decreased (p < 0.01) the levels of intracellular calcium and cAMP in frozen-thawed spermatozoa. 1,2-diacylglycerol content was also decreased significantly (p < 0.01) in spermatozoa cryopreserved in presence of additives. Moreover, significant (p < 0.01) improvement in post-thaw motility, viability and membrane integrity of spermatozoa on addition of taurine or trehalose clearly indicated the reduced level of capacitation-like changes in buffalo spermatozoa.  相似文献   

15.
This study investigated the apoptosis-like events associated with cryopreservation process and their relationship with cryocapacitation in buffalo (Bubalus bubalis) sperm. A total of 49 semen ejaculates from seven bulls were studied for structural changes in sperm following cryopreservation. Apoptotic changes were detected by assays specific for translocation of phosphatidylserine (PS) to the cell surface, alterations in membrane permeability and mitochondrial membrane potential (MMP), and DNA integrity. A significant (p < 0.01) percentage of cryopreserved sperm showed externalization of PS and early apoptotic changes and lowered MMP when compared with the fresh sperm. Freezing and thawing of sperm increased permeability to YOPRO-1, an impermeant fluorescent dye. However, on TUNEL staining, cryopreserved sperm showed no breach in DNA integrity. The sperm capacitation status was evaluated by chlortetracycline (CTC) fluorescence pattern, in which a significant (p < 0.01) percentage of cryopreserved sperm were found to be capacitated. The capacitated sperm (Pattern B) was positively correlated with the aforementioned apoptotic events. In conclusion, cryopreservation process induced early apoptosis-like changes in buffalo sperm, and a close link exists between cryocapacitation and apoptosis during cryopreservation of sperm.  相似文献   

16.
The present study assessed the effects of incorporation of Taurine or Trehalose in extender on immunolocalization of tyrosine phosphoproteins, Cryocapacitation and other sperm quality parameters (motility, viability and membrane integrity) in post‐thawed sperm from Buffalo (Murrah) and Cattle (Karan Fries). Six ejaculates from six individual bulls from both species were chosen at random and split into four aliquots: one aliquot without dilution (fresh sample), another diluted in egg yolk tris‐citrate (EYTC) extender and the rest of aliquots with EYTC dilution supplemented with taurine (50 mm ) or trehalose (100 mm ), respectively, and cryopreserved. Following cryopreservation, semen were thawed and assessed for standard semen quality parameters. Extent of capacitation in cryopreserved spermatozoa was measured by inducing in vitro acrosome reaction followed by dual staining. Immunolocalization of tyrosine phosphoproteins was carried out by immunocytochemistry using primary antibody clone pT‐154 (anti‐phosphotyrosine antibody) and FITC‐conjugated secondary antibody. Immunofluorescent signals were analysed for level of protein tyrosine phosphorylation in spermatozoa. Post‐thaw semen evaluation showed supplementation of taurine or trehalose to EYTC extender significantly (p < 0.05) increased motility, viability and membrane integrity of spermatozoa in both species. Percentage of cryocapacitated spermatozoa was significantly (p < 0.05) higher in cattle as compared to buffalo and degree of cryocapacitaion of spermatozoa decreased significantly (p < 0.05) upon supplementation of additives in both the species. It was also found that tyrosine phosphoproteins were localized differentially in fresh and cryopreserved spermatozoa. Supplementation of taurine or trehalose to freezing extender changed the localization of tyrosine phosphoproteins in cryopreserved spermatozoa similar to fresh in both the species. The results obtained clearly indicated that supplementation of taurine or trehalose to EYTC prior to cryopreservation improves Buffalo and Cattle sperm quality in terms of cryocapacitation and immunolocalization of tyrosine phosphoproteins during freezing–thawing process.  相似文献   

17.
Freezing and cooling of spermatozoa during cryopreservation for artificial insemination causes ultrastructural changes in the acrosome and plasma membrane which reduces longevity and fertility. Cryopreservation-induced capacitation-like changes and reduced ability of spermatozoa to bind to the cells of the reproductive tract of the bitch may contribute to the reduced fertility of cryopreserved spermatozoa. Previous studies in the dog have investigated the effects of extending and cooling spermatozoa on the plasma membrane but often only after freeze-thawing and not in conjunction with an assessment of their ability to bind to uterine tube epithelial explants. This study investigated the effect of each stage of the cryopreservation process on capacitation and attachment to the reproductive tract of the bitch. The capacitation status of spermatozoa was studied over time after cryopreservation using a chlortetracycline and Hoechst 33258 stain. The ability of spermatozoa to bind to uterine tube epithelial explants was studied using Hoechst 33342 stain. Extending, cooling and freeze-thawing promoted capacitation and decreased the spermatozoal binding ability. The effect of each stage appeared to be cumulative with the freeze-thawing stage being the most dramatic. The results suggested that the cumulative effect of each stage of the cryopreservation process results in the promotion of capacitation before spermatozoa have reached the site of fertilisation, and therefore spermatozoa have reduced ability to attach to epithelial cells. These effects are contributory factors to the reduced fertility of cryopreserved spermatozoa.  相似文献   

18.
Computer-automated sperm-head morphometry was used in this study to determine the effects of cryopreservation on red deer sperm-head morphometry. Epididymal sperm samples were collected from 40 mature stags and were divided. One portion was diluted at room temperature in a Tris-citrate egg yolk medium, containing 6% 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 length, width, area, perimeter and shape factor (length/width), for a minimum of 135 spermatozoa were determined for each slide by means of the Sperm-Class Analyser (SCA). Firstly, our results show that cryopreservation substantially reduced (p < 0.001) sperm motility and plasma membrane and acrosome integrities. In addition, sperm heads were significantly smaller in cryopreserved spermatozoa than in the companion extended samples for area (32.05 microm2 vs 32.56 microm2; p < 0.05), length (8.46 microm vs 8.53 microm; p < 0.0001) and shape factor (1.833 vs 1.849; p < 0.0001) for all stags. These differences were found within 29 of 40 stags (75%) for at least three of the morphometric parameters. The individual variability (CV) of sperm head measurements from extended samples was negatively correlated (p < 0.005) with the per cent of change in sperm head measurements after cryopreservation for area (r = -0.465), width (r = -0.483) and perimeter (r = -0.375). Thus, the lower the sperm head variability in the extended samples, the greater the sperm change as a consequence of the cryopreservation. These results suggest that the variability (heterogeneity) in sperm head dimensions of individual stags may be a good indicator of sperm freezability.  相似文献   

19.
Cryopreservation of epididymal spermatozoa is often performed after shipping the excised testis–epididymis complexes, under refrigeration, to a specialized laboratory. However, epididymal spermatozoa can be collected immediately after excision of the epididymis and sent extended and refrigerated to a laboratory for cryopreservation. In this experiment, we evaluated the effect of both methods of cold storage bovine epididymal spermatozoa as well as of two different extenders on spermatozoa characteristics after freeze–thawing. For that, spermatozoa collected from the caudae epididymis of 19 bulls were extended and cryopreserved in either AndroMed® or a Tris–egg yolk (TEY)‐based extender. Cryopreservation of sperm cells was performed immediately after castration (Group A, n = 9) or after cold storage for 24 h diluted in the two extenders and (Group B, n = 9) and also after cold storage for 24 h within the whole epididymis (Group C, n = 10). Sperm subjective progressive motility (light microscopy), plasma membrane integrity (hypoosmotic swelling test) and sperm viability (eosin–nigrosin) were evaluated. In vitro fertilization and culture (IVF) was performed to assess the blastocyst rate. No differences (p > 0.05) were observed on post‐thaw sperm parameters between samples from Group A, B and C. TEY extended samples presented a higher (p < 0.01) percentage of progressive motile and live sperm, than those extended in AndroMed®. Blastocyst rate after IVF differed only (p < 0.05) between the reference group (IVF performed with frozen semen with known in vitro fertility) and Group A extended in AndroMed®. We conclude that when cryopreservation facilities are distant from the collection site, bovine epididymal sperm can be shipped chilled overnight either within the epididymal tail or after dilution without deleterious effect on post‐thaw sperm quality. TEY extender was more suitable for cold storage and freezing bovine epididymal sperm, than the commercial extender AndroMed®.  相似文献   

20.
Phosphorylation of tyrosine residues on sperm protein is a known indicator of capacitation and a major intracellular signalling event. There is evidence that sperm cryopreservation promotes tyrosine phosphorylation and is associated with reduced fertility of spermatozoa. Under this study, cryoprotective role of different additives namely taurine, trehalose, catalase and 4‐bromophenacyl bromide on buffalo sperm quality was evaluated. Buffalo semen was cryopreserved in tris‐based egg yolk extender supplemented with additives like taurine (50 mm ) or trehalose (100 mm ) or 4‐bromophenacyl bromide (200 μm ) or catalase (100 U/ml) and used for assessment of levels of tyrosine phosphorylation in frozen‐thawed spermatozoa. The results obtained were compared with the level of protein tyrosine phosphorylation of semen cryopreserved in tris‐based egg yolk extender without additives. Proteins were extracted from a total number of nine ejaculates from three individual buffalo bulls chosen at random and analysed for tyrosine phospho‐proteins using SDS–PAGE followed by immunoblotting. Monoclonal anti‐phosphotyrosine antibody (Clone pT‐154) was used as primary antibody followed by treatment with HRP‐conjugated secondary antibody. Signals were detected on X‐ray film using chemiluminescence. Nine proteins (p20, p30, p32, p38, p49, p56, p59, p72 and p86) were found to be tyrosine phosphorylated in cryopreserved spermatozoa. Supplementation of additives significantly (p<0.05) reduced the level of protein tyrosine phosphorylation in spermatozoa. Moreover, this study showed improved (p<0.05) post‐thaw motility, viability and membrane integrity of spermatozoa on addition of these additives. The results obtained clearly indicate reduced level of capacitation like changes on supplementation of additives in terms of protein tyrosine phosphorylation.  相似文献   

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