海藻糖对猪精液冷冻保存效果的影响

在传统的Tris-柠檬酸-葡萄糖稀释液基础上，分别添加25％、50％、75％、100％的海藻糖，研究不同浓度海藻糖对猪精液冷冻后精子质量的影响。结果表明，海藻糖相对于对照TCG稀释液能够显著改善和提高猪精液的冷冻效果，其最佳添加浓度为25％，冷冻-解冻后猪精子活力、活率、线粒体活性、质膜完整性以及顶体完整率均显著提高（P〈0．05），分别达到41．38％、46．34％、44．56％、43．51％和64．09％。海藻糖可以明显抑制精子获能，获能处理前精子获能率仅为3．68％，而获能处理后达到41．82％，有利于促进精子获能。精液稀释液中甘油的适宜添加浓度为2％，海藻糖只有与甘油共同作用，才能在冷冻-解冻过程更加有效地保护精子。猪精子活力、活率、线粒体活性、质膜完整率、顶体完整率等之间存在极显著的正相关关系（P〈0．01），而与获能处理前精子的获能率存在显著的负相关关系（P〈0．05）。     

Trehalose in glycerol-free freezing extender enhances post-thaw survival of boar spermatozoa

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.     

鸵鸟卵黄对猪精子冷冻后质量的影响

为了提高猪冷冻精液品质和精子抵抗低温打击的能力,本研究以5%、10%、15%、20%和25%等不同浓度的鸵鸟卵黄作为冷冻保护剂,以20%的鸡蛋卵黄和20%的鸽蛋卵黄为对照,将冷冻-解冻后的精子活率、质膜完整率和顶体完整率作为评价指标,分析鸵鸟卵黄对猪精子的抗冷冻保护作用。结果表明：稀释液中添加20%鸽蛋卵黄时,精子活率、顶体完整率和质膜完整性分别为52.11%、55.62%和54.94%,显著高于其他组（P〈0.05）。虽然稀释液中添加15%鸵鸟卵黄时,冷冻-解冻后精子活率、顶体完整率和质膜完整率显著高于5%、10%、20%和25%鸵鸟卵黄组,但仍然显著低于稀释液中添加20%鸽蛋卵黄处理组。本研究表明,鸵鸟卵黄在冷冻过程中对猪精子具有一定的保护作用,但相对于鸽子蛋和鸡蛋卵黄效果并不理想。     

The Effect of Trehalose Supplementation of INRA-82 Extender on Quality and Fertility of Cooled and Frozen-Thawed Stallion Spermatozoa

Stallion semen cryopreservation is often associated with poor post-thaw sperm quality. Sugars act as nonpermeating cryoprotectants. The aim of the present study was to evaluate the cryoprotective effect of trehalose on stallion sperm quality and field fertility rates subjected to cooling and freeze–thaw process. Semen samples were collected from six Arabian stallions, divided into five different treatments in a final concentration of 100 × 10⁶ sperm/mL by using INRA-82 extender containing 0, 25, 50, 100, and 200 mM of trehalose then subjected to both cold storage and cryopreservation. Sperm motility, acrosome, plasmatic membrane, and DNA integrity were analyzed, and 57 mares were used to evaluate the field fertility of chilled and frozen-thawed semen. Results showed that the extender containing 100 mM trehalose only increased the functional acrosomal, plasma membrane, and DNA integrities. The inclusion of 50 mM trehalose in semen extender resulted in significantly (P < .05) increased post-thaw total motility compared to the control group, and chilled semen achieved higher pregnancy rates compared to the frozen-thawed one. Pregnancy rate of mares inseminated with frozen-thawed semen (P < .05; 46.15% vs. 36.36%, respectively) was lower than those inseminated with chilled semen (76.47% vs. 68.75%, respectively) but higher than control. In conclusion, addition of 50 mM trehalose yielded the highest quality stallion semen after cooling and post-thawing in terms of motility, integrities of acrosome, membrane, and DNA as well as improved field fertility.     

Metformin blocks mitochondrial membrane potential and inhibits sperm motility in fresh and refrigerated boar spermatozoa

Metformin is clinically used to treat diabetes. Given its role‐impacting metabolism, metformin has been also added to semen cryopreservation media showing specie‐dependent effects. We aimed to investigate metformin effects in both fresh (38.5°C for 2, 24 hr) and refrigerated (17°C for 10 days) boar spermatozoa. Metformin (2 hr) does not affect fresh sperm viability, membrane lipid organization nor acrosome integrity. However, metformin (24 hr) blocks sperm ΔΨm and significantly reduces % motile spermatozoa (65%), % progressive spermatozoa (50%), % rapid (100%), velocities VCL (69%), VSL (86%), VAP (78%) and motility coefficients. Metformin‐including extender does not modify sperm viability, membrane lipid organization or acrosome integrity. Furthermore, it significantly reduces high ΔΨ‐population spermatozoa at refrigeration day 4. Metformin also significantly reduces sperm motility during refrigeration. Summarizing, metformin inhibits both boar sperm ΔΨ and motility in any sperm condition studied: fresh and refrigerated. These findings dissuade metformin as an additive to improve boar sperm quality.     

海藻糖、二甲乙酰胺对公猪精液冷冻保存效果的研究

采用5% 二甲乙酰胺(DMA)(V/V)完全替代甘油,比较乳糖、海藻糖对精液冷冻保存效果的影响。结果表明,海藻糖显著提高了冷冻——解冻后精子成活力(49.32%±1.52%)与顶体完整性 (47.33%±1.16%)(P<0.05)。然后利用海藻糖替代乳糖,评价不同浓度的DMA对公猪精液冷冻保存的影响。结果表明,当DMA添加量为4%时,解冻后精子活率、成活力、顶体完整率分别为(45.17±0.56)%、(50.33±0.67)%、(48.30±1.44)%,均显著高于3% DMA、6% DMA添加组(P<0.05),精子活率显著高于5% DMA添加组(P<0.05),但精子成活力、顶体完整性与其差异不显著(P>0.05)。因此,当利用海藻糖作为冷冻保存基础稀释液,DMA最适添加量为4%。     

抗氧化剂在猪精液冷冻保存技术中的应用

近年来,在猪精液冷冻保存技术中应用抗氧化剂以提高冷冻精液质量的研究受到了广泛关注。国内外相继报道,添加甲基黄嘌呤、丁羟甲苯、谷胱甘肽、超氧化物歧化酶和过氧化物酶、维生素E及褪黑素等抗氧化剂可以有效改善冷冻保存猪精液的精子运动学参数,保护精子质膜、顶体和DNA完整性,提高冷冻-解冻后精子的受精能力。为了更好地了解抗氧化剂的抗精子冷冻损伤的作用机制、客观地评价不同抗氧化剂的应用效果及展望其在猪精液冷冻保存技术中的应用前景特综述如下。     

Improved conception rates in sows inseminated with cryopreserved boar spermatozoa prepared with a more optimal combination of osmolality and glycerol in the freezing extender

Cryoprotectant agents (CPAs) are added in freezing extenders to prevent intracellular ice crystal formation. However, it has been reported that high dose of CPAs confer toxicity on spermatozoa. Recently, the reduction of intracellular water by a high osmolality solution has also resulted in the suppression of ice crystal formation in spermatozoa, suggesting that the optimal combination of glycerol concentration and freezing extender osmolality could contribute to the development of effective sperm cryopreservation techniques. In this study, we investigated the motility, membrane and acrosomal integrity of frozen-thawed boar spermatozoa treated with freezing extender (NSF) of varying osmolalities (300, 400, 500 mOsm/kg) and final concentrations of glycerol (0.5, 1, 2, 3%). The spermatozoa that were treated at 400 mOsm/kg and 2% glycerol showed significantly higher rates of motility and membrane integrity compared with those in other treatment groups. In addition, the conception and implantation rates of swine artificially inseminated with spermatozoa frozen by the novel freezing extender (conception; 79%, implantation; 57.5%) were significantly higher than those of frozen-thawed spermatozoa treated in the conventional NSF (300 mOsm/kg, 3% glycerol) (conception; 29%, implantation; 33.8%). From these results, we concluded that the novel hyperosmotic (400 mOsm/kg) and low-glycerol (final concentration 2%) freezing extender is beneficial for the cryopreservation of boar spermatozoa.     

鸵鸟卵黄低密度脂蛋白对猪精子冻后品质的影响

在家畜精液冷冻中,卵黄被广泛应用,且其中的低密度脂蛋白(LDL)对精子起主要保护作用。本研究利用含6%、7%、8%和9%鸵鸟卵黄LDL配制的稀释液制作猪细管冷冻精液,分析鸵鸟卵黄LDL对冷冻-解冻后猪精子质量参数的影响。结果表明:在含不同浓度鸵鸟卵黄LDL的稀释液中,8%LDL的稀释液冷冻效果最好,冻后精子活率平均可达52.13%,显著高于其他组(P<0.05);精子顶体完整率平均为58.33%,质膜完整率为72.38%,与其他处理组相比差异显著(P<0.05)。但与鸡蛋卵黄LDL和鸽子蛋卵黄LDL处理组相比,鸵鸟卵黄LDL处理组冷冻-解冻后猪精子质量参数相对较低。本研究表明,虽然鸵鸟卵黄LDL在冷冻过程中对猪精子具有一定的保护作用,但相对于鸽子蛋和鸡蛋卵黄LDL效果并不理想。     

二甲基甲酰胺对猪精液冷冻保存效果的影响

用二甲基甲酰胺(DMF)完全替代甘油,比较不同平衡时间和不同DMF添加量对猪精液冷冻保护效果的影响。结果表明,DMF能完全替代甘油,获得较好的冷冻保护效果。最佳平衡时间为90 min,解冻后精子活力为(44.57±0.72)%,显著高于对照组和其他组(P0.05)。当DMF添加量为5%时,冻后精子活力、活率、线粒体活性、顶体完整率和质膜完整率分别为(49.91±0.39)%(、46.51±0.26)%、(47.51±0.52)%(、49.84±0.56)%、(46.30±1.61)%,均显著高于2%、3%、6%DMF添加组(P0.05),但与4%DMF添加组相比,冻后精子活力、活率和质膜完整率差异不显著(P0.05)。本试验结果表明,DMF最适添加量为5%。     

Effects of glycerol concentration, equilibration time and temperature of glycerol addition on post-thaw viability of boar spermatozoa frozen in straws

Experiments were conducted to study the effect of glycerol concentration, equilibration time and temperature of glycerol addition on post-thaw viability of boar spermatozoa after cryopreservation in straws. Semen (split ejaculate) in maxi-straws (6 mm o.d.) was frozen using a programmable freezing chamber. Three methods for in vitro sperm evaluation were used: motility (MOT), acrosome integrity (NAR) and flow cytometric analysis of sperm treated with carboxyfluorescein diacetate and propidium iodide to assess sperm plasma membrane integrity (PMI). No interactions were found among the three variables evaluated. Length of prefreeze exposure to glycerol, ranging from .5 min to 75 min, had no effect on post-thaw sperm viability. Exposure of sperm to a glycerol-containing extender medium at 5 degrees C gave improved post-thaw viability over that exposed at 0 degree C (P less than .05). Glycerol at a concentration of 3 or 4% resulted in maximum post-thaw MOT. Acrosome integrity values were greatest for 2 and 3% glycerol, whereas PMI was greatest when glycerol concentration was 4 to 6%. The primary cryoprotective effect of glycerol on boar semen may be extracellular. It is concluded that 3 or 4% glycerol gives maximum viability of frozen-thawed spermatozoa when the present methods are employed.     

Use of Glutamine and Low Density Lipoproteins Isolated from Egg Yolk to Improve Buck Semen Freezing

To improve the results obtained with a reference cryopreservation extender (control extender: Triladyl® + 20% (v/v) egg yolk + 6.4% (v/v) glycerol) for freezing caprine semen, glutamine was added to 18 split ejaculates at concentrations of 0, 20, 40, 80 and 120 m m (experiment 1). In experiment 2, glutamine was added to 18 split ejaculates at concentrations of 20, 25, 30, 35 and 40 m m . In the third experiment, the egg yolk was replaced with the low-density lipoprotein (LDL) fraction of egg yolk. The quality of frozen then thawed spermatozoa in each extender was compared using computer-assisted semen analysis. In experiment 1, glutamine at concentrations of 20 m m and 40 m m significantly improved sperm motility compared with the control extender. However, at 120 m m , a significant decrease in motility and velocity was observed. In experiment 2, motility, curvilinear velocity and amplitude of lateral head displacement (ALH) were improved in glutamine at 25 m m compared with the control. In experiment 3, 8% LDL and 25 m m glutamine significantly improved sperm motility, straight line velocity and ALH. In the fourth experiment, the quality of the previously defined freezing extender (Triladyl® + 8% (v/v) LDL + 25 m m glutamine + 6.4% (v/v) glycerol) was tested by comparing acrosome, tail membrane, plasma membrane and DNA integrity in 18 split ejaculates of frozen then thawed spermatozoa with spermatozoa that had been frozen then thawed in the control extender, and with spermatozoa from fresh, unfrozen sperm. The percentage of spermatozoa with intact acrosomes and tail membranes was significantly higher with the newly defined extender than that observed with the control extender. There was no significant difference in the percentage of spermatozoa with intact DNA between the frozen and fresh semen.     

The benefits of cooling boar semen in long‐term extenders prior to cryopreservation on sperm quality characteristics

This study investigated the effects of long‐term extenders on post‐thaw sperm quality characteristics following different holding times (HT) of boar semen at 17 and 10°C. Sperm‐rich fractions, collected from five boars, were diluted in Androhep^® Plus (AHP), Androstar^® Plus (ASP), Safecell^® Plus and TRIXcell^® Plus (TCP) extenders. The extended semen samples were held for 2 hr at 17°C (HT 1) and additionally for 24 hr at 10°C (HT 2), after they were evaluated and frozen. CASA sperm motility and motion patterns, mitochondrial membrane potential (MMP), plasma membrane integrity (PMI) and normal apical ridge (NAR) acrosome integrity were assessed in the pre‐freeze and frozen‐thawed semen. The Vybrant Apoptosis Assay Kit was used to analyse the proportions of viable and plasma membrane apoptotic‐like changes in spermatozoa. Results indicated that boar variability, extender and HT significantly affected the sperm quality characteristics, particularly after freezing‐thawing. Differences in the pre‐freeze semen were more marked in the sperm motion patterns between the HTs. Pre‐freeze semen in HT 2 showed significantly higher VCL and VAP, whereas no marked effects were observed in the sperm membrane integrity and viability (YO‐PRO‐1^?/PI^?) among the extenders. Post‐thaw sperm TMOT and PMOT were significantly higher in the AHP and ASP extenders of HT 2 group, whereas VSL, VCL and VAP were markedly lower in the TCP extender. Furthermore, spermatozoa from the AHP‐ and ASP‐extended semen of HT 2 group were characterized by higher MMP, PMI and NAR acrosome integrity following freezing‐thawing. In most of the extenders, the incidence of frozen‐thawed spermatozoa with apoptotic‐like changes was greater in HT 1. The findings of this study indicate that holding of boar semen at 10°C for 24 hr in long‐term preservation extenders modulates post‐thaw sperm quality characteristics in an extender‐dependent manner. These results will further contribute to the improvement in the cryopreservation technology of boar semen.     

海藻糖和甘油相互协同提高绒山羊精液冷冻保存品质

本实验旨在研究不同浓度的海藻糖和甘油相互协同对绒山羊精液冷冻保存的影响。将0 mmol/L (T0)、50mmol/L(T50)的海藻糖和0%(G0)、1%(G1)、2%(G2)、3%(G3)的甘油分别组合为T0G0、T0G1、T0G2、T0G3、T50G0、T50G1、T50G2和T50G3。以Tris-柠檬酸-葡萄糖(TCG)为基础稀释液,分析不同组合对绒山羊精液冷冻保存的影响。检测解冻后精子活力、运动参数、DNA完整率、顶体、质膜完整率、抗氧化水平。结果表明:海藻糖和甘油联合添加时精子冷冻保存效果显著高于单独添加海藻糖或甘油组,其中T50G1组作用最显著。在基础稀释液中添加50 mmol/L(T50)的海藻糖时,精子冷冻解冻后的活力、质膜完整率随着甘油浓度的升高而降低,而在基础稀释液中不添加海藻糖时,精子冷冻解冻后的活力、质膜完整率随着甘油浓度的升高而升高。综上表明,海藻糖和甘油通过协同作用提高精子冷冻保存效果,两者发挥作用的最适浓度为50 mmol/L海藻糖和1%甘油,并且海藻糖和甘油协同作用对精子活力以及质膜完整性具有浓度依赖性。     

Cryopreservation of boar semen by egg yolk-based extenders containing lactose or fructose is better than sorbitol

The present study determined the effect of different types of sugars (lactose, fructose, glucose and sorbitol) used in egg yolk-based extender on the post-thawed boar semen quality. Twenty-two ejaculates from 6 fertility-proven Yorkshire boars were cryopreserved by liquid nitrogen vapor method. Sperm motility, viability, acrosome integrity and intact functional plasma membrane were determined at 0, 2 and 4 hr after thawing. It was found that the lactose-based extender resulted in a higher percentage of post-thawed sperm motility, viability, intact acrosome and functional plasma membrane than sorbitol-based extender (P<0.05) and fructose-based extender yielded a higher post-thawed sperm motility and viability than sorbitol-based extender (P<0.05). It could be concluded that sorbitol was not an effective sugar for the cryopreservation in boar semen.     

Effect of incorporation of additives in tris-based egg yolk extender on buffalo (Bubalus bubalis) sperm tyrosine phosphorylation during cryopreservation

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.     

Breed of Boar Influences the Optimal Concentration of Gamma‐oryzanol Needed for Semen Cryopreservation

The aim of this study was to investigate the influence of boar breed on the optimal concentration of gamma‐oryzanol on the qualities of cryopreserved boar semen. Semen was collected from 20 boars (10 Duroc, 5 Large white and 5 Landrace boars). The semen sample was divided into five groups (A–E) according to the concentration of gamma‐oryzanol in extender II, that is 0, 0.08, 0.16, 0.24 and 0.32 mm , respectively. The semen was cryopreserved by nitrogen vapour and storage in nitrogen tank (?196°C). After storage for a week, samples were thawed at 50°C for 12 s and evaluated for progressive motility, sperm viability and acrosome integrity. The results demonstrated that gamma‐oryzanol significantly improved progressive motility, viability and acrosome integrity of frozen–thawed boar semen. Considering the influence of breeds on the optimal concentration of gamma‐oryzanol, for Duroc boar, gamma‐oryzanol at 0.16 mm (group C) yielded the highest percentage of progressive motility, sperm viability and acrosome integrity. For Large white and Landrace boars, gamma‐oryzanol at 0.24 mm (group D) showed a significantly higher percentage of progressive motility, viability (not significant in Landrace) and acrosome integrity than other concentrations. In conclusion, the optimal concentration of gamma‐oryzanol needed for boar semen cryopreservation in lactose–egg yolk (LEY) freezing extender is not only depended on individual boar but also breed of boar, that is 0.16 mm for Duroc and 0.24 mm  for Large white and Landrace.     

Evaluation of glucose as a cryoprotectant for boar semen

Fertility parameters of boar spermatozoa were evaluated in vitro, after freeze-thawing the semen in three different extenders containing permeable and non-permeable cryoprotectants: A (111.0 mM Tris, 31.4 mM citric acid, 185.0 mM glucose, 20 per cent egg yolk, 3 per cent glycerol and 100 iu/ml penicillin G); B (200 mM Tris; 70.8 mM citric acid, 55.5 mM glucose, 20 per cent egg yolk, three per cent glycerol and 100 iu/ml penicillin G); C (200 mM Tris, 70.8 mM citric acid, 55.5 mM fructose, 20 per cent egg yolk, 3 per cent glycerol and 100 iu/ml penicillin G). The freeze-thawing techniques were the same for each extender. Eight ejaculates from four boars were obtained; the sperm-rich fraction of each ejaculate was extended in each of the three media at a final concentration of 400 x 106 sperm/ml, loaded into 0.5 ml straws and frozen at a rate of 30 degrees C/minute to -196 degrees C. The straws were thawed at 60 degrees C for eight seconds. Sperm motility, acrosomal integrity and in vitro sperm penetration through the zona pellucida of gilt oocytes matured in vitro were evaluated. The motility of unfrozen spermatozoa was 93.1 per cent compared with 60.7 per cent, 48.2 per cent and 35 per cent for sperm frozen in extenders A, B and C respectively; these values were all significantly different (P<0.05). There was no significant decline in sperm motility after incubation for 30 minutes in extender A, but there were significant decreases in sperm motility after 30 minutes of incubation in B and C. The percentage acrosomal integrities were 97.2 per cent for the control and 45.5 per cent, 30.3 per cent and 16.8 per cent for the frozen-thawed spermatozoa in extenders A, B and C respectively. The results of the in vitro penetration assay were 80.7 per cent when using control spermatozoa, and 42.2 per cent, 18.4 per cent and 3.3 per cent when using frozen-thawed spermatozoa in extenders A, B and C respectively     

辅酶Q10对绒山羊精液冷冻保存效果的影响

旨在探讨辅酶Q10对绒山羊精液冷冻保存效果的影响。利用添加不同浓度辅酶Q10(4、40、400?滋g/mL)的精液冷冻稀释液对绒山羊精液样本进行冷冻保存,待冷冻精液解冻后,采用流式细胞仪和计算机辅助精液分析系统(CASAS)分别检测不同精液样本的精子活率、质膜完整率、顶体完整率、DNA完整率、线粒体膜电位和细胞内ROS水平。结果表明,当冷冻稀释液中添加浓度为40μg/mL辅酶Q10时,经历冷冻—解冻过程的绒山羊精液样本的精子活率、质膜完整率、顶体完整率均显著高于对照组(P<0.05);在冷冻稀释液中添加浓度为40μg/mL或400μg/mL的辅酶Q10均能显著提高线粒体膜电位并降低细胞内ROS水平(P<0.05)。综上所述,在冷冻稀释液中添加40μg/mL的辅酶Q10能够显著提高绒山羊精子抗氧化能力和冷冻保存效果。     

Fertilizing capacity of boar semen frozen in an extender supplemented with ostrich egg yolk lipoprotein fractions--a pilot study

A limited field trial was performed to evaluate the fertilizing capacity of boar spermatozoa frozen in an extender supplemented with lipoprotein fractions isolated from ostrich egg yolk (LPFo). Boar semen, diluted in an extender containing lactose with lyophilized lipoprotein fractions, glycerol and Orvus Es Paste (lactose-LPFo-G), was frozen using a controlled programmable freezer. Sperm characteristics, such as motility, plasma membrane and acrosome integrity, and mitochondrial function were monitored. Post-cervical artificial inseminations (post-CAIs) in multiparous sows (Polish Large White) were performed using the Soft & Quick catheter/cannula set. Sows were inseminated 2 to 3 times within one oestrus. Possible returns of sows to oestrus were determined from 21 to 30 days after post-CAIs. In this field trial, sows inseminated with 2 x 10(9) motile frozen-thawed spermatozoa resulted in pregnancy and farrowing rates of 75%, respectively. The average piglets born live was 10.5 +/- 0.4 (mean +/- SEM). The data of this study showed that post-CAI of boar semen frozen in LPFo-containing extender has the potential to provide acceptable fertility results. Further investigations are needed to elucidate the cause of variations in pregnancy/farrowing rate associated with frozen-thawed boar semen.