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）。     

不同稀释剂对猪冷冻精液精子活率的影响

手握法采集12月龄大约克种公猪精液，在37℃下离心，弃去精清，收集浓缩段富含精子部分，用7种不同的稀释液进行稀释，应用液氮熏蒸法制作颗粒冻精。结果表明，在7种稀释液中，7号稀释液优于其他6种稀释液（P〈0．05）：与其他的冷冻保护剂相比，甘油的冷冻保护性能较好（P〈0．01），其适宜浓度为2～4mL／L：干解冻（40℃～45℃）效果优于湿解冻，解冻后精于活率达0．6～0．49（P〈0．05）；稀释液中添加安钠咖可有效地延长精于的冻后存活时间（P〈0．01）。     

海藻糖对民猪精液冷冻保存的影响

为研究海藻糖在民猪精液冷冻中的作用,获得最佳民猪精液冷冻液成分,本试验在BTS、Modena和Zorlesco 3种稀释液基础上添加0.15 mol/L海藻糖,及在Zorlesco稀释液中分别添加0 mol/L、0.1 mol/L、0.15 mol/L和0.2 mol/L的海藻糖,研究海藻糖在不同稀释液中及其不同浓度对冷冻的民猪精子活率、质膜完整率、顶体完整率和线粒体膜电位的影响。结果表明,在Zorlesco稀释液中添加0.15 mol/L海藻糖可明显提高民猪冷冻精子的质量,使精子活率、质膜完整性、顶体完整率和线粒体活性分别达到(44.0±2.4)%、(58.2±2.4)%、(53.2±2.1)%和(51.3±2.3)%,为各组最佳(P<0.05)。将0.15 mol/L海藻糖分别添加在BTS、Modena和Zorlesco3种稀释液中发现,其中在Zorlesco稀释液添加海藻糖效果优于其他两组(P<0.05)。但海藻糖对冷冻前精子的保护作用不明显(P>0.05)。因此,在Zorlesco稀释液中添加1.5 mol/L的海藻糖能够明显提高民猪精子冷冻后质量,是民猪冷冻保存的适宜保护液。     

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。     

海藻糖和维生素C对猪精液冷冻保存效果的影响

试验比较了在冷冻稀释液中添加不同浓度海藻糖(0.025,0.05,0.1 mol/L)以及添加10 mg/L维生素C对猪精液冷冻保存效果的影响.结果:(1)添加0.025 mol/L海藻糖组的精子冻后活率与复苏率分别跟对照组相比无显著差异(P>0.05),但添加浓度为0.05,0.1 mol/L的海藻糖组的精子活率和复苏率显著低于对照组(P<0.05).(2)在猪精液冷冻保存稀释液中,添加维生素C组的精子冻后活率和复苏率极显著高于对照组(P<0.01).表明在猪精液冷冻液中,添加0.025,0.05,0.1 mol/L 3种不同浓度的海藻糖对猪精液没有起到保护作用,其中后两者对之有降低的作用;而添加10 mg/L维生素C可取得较好的冷冻保存效果.     

稀释液中添加海藻糖对猪冷冻精液质量参数和活性氧的影响

本试验旨在探讨海藻糖对猪精子冷冻效果以及精子内活性氧(ROS)的含量影响。试验分对照组和4个海藻糖处理组(0.025,0.05,0.1和0.2 mol/L)。精子冷却后,添加0.1 mol/L海藻糖处理组精子活力显著(P<0.05)高于对照组,而精子内和稀释液中各组间ROS发生量都没有显著的差异。精子冷冻解冻后,添加0.05 mol/L海藻糖处理组的精子活力显著(P<0.05)高于对照组;添加0.05 mol/L和0.1 mol/L海藻糖处理组的精子生存率显著(P<0.05)高于对照组;添加0.1 mol/L海藻糖处理组顶体完整的精子百分比显著(P<0.05)高于对照组;4个海藻糖处理组膨胀精子百分比都显著(P<0.05)高于对照组;添加0.025 mol/L海藻糖处理组ROS水平显著(P<0.05)低于对照组。结果表明:海藻糖对精子冷冻保存是有益的,且能抑制精子内ROS的发生,但它的作用机制有待于进一步的研究。     

谷胱甘肽对杜洛克猪精子冷冻保存效果的影响

为了探讨冷冻保存Ⅰ液中添加不同浓度谷胱甘肽(GSH)对杜洛克公猪精子冷冻保存效果的影响,试验将冷冻-解冻处理的精液分为6组,分别为对照组(冷冻保存Ⅰ液)和试验组(分别在冷冻保存Ⅰ液中添加1.0,1.5,2.0,2.5,3.0 mmol/L的GSH),在液氮中保存,然后检测精子活力、运动参数、质膜完整率、顶体完整率、线粒体活性,活性氧(ROS)水平,丙二醛(MDA)和ATP含量,以及超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)活性,以此来评价解冻后的精液品质。结果表明：与对照组相比,除GSH添加浓度为3.0 mmol/L时精子活力降低外,其他添加浓度精子活力均提高,其中添加浓度为2.5 mmol/L时提高最显著(P<0.05)。与对照组相比,GSH添加浓度为2.5 mmol/L时猪精子在解冻后各项运动参数均显著提高(P<0.05),添加浓度为2.0,3.0 mmol/L时对猪精子部分运动参数也有一定提高,而添加浓度为1.0 mmol/L时各项运动参数降低。与对照组相比,添加不同浓度GSH时精子质膜完整率、顶体完整率、线粒体活性均提高,其中...     

猪精子冷冻损伤的研究

冷冻保存后的猪精子，结构受到损伤，妊娠率下降。其超微结构变化与正常鲜精的顶体反应非常相似，包括质膜膨胀碎裂，顶体外膜泡状化。我们提议上述变化称为假顶体反应。     

弱酸对猪精子活率及产仔性别的影响

分别向猪精液中加入醋权、乳酸、草酸、柠檬酸,改变了精液的ＰＨ值,并测定精子的活率,当精液的ＰＨ值达到６．５,精子沃经达到６０％时,将此褒庇人发情母猪人工配种,结果当每ｍｌ精液中加入１％的醋酸０．１５ｍｌ（ｐＨ６．５）时,对母猪的产仔数影响不显著（Ｐ〉０．０５）,但与对照组相比可显著地提高仔母猪的比例（Ｐ〈０．０５）。     

菟丝子提取物对猪精子冷冻效果的影响

在猪精液冷冻液中添加不同浓度的菟丝子提取物,研究冻后精子的形态正常率、质膜完整率、SOD活性及MDA含量,探讨菟丝子提取物对猪精液冷冻保存效果。结果表明,冷冻-解冻后,猪精子形态正常率、质膜完整率和SOD活性均显著降低,MDA含量显著高于对照组(P<0.05)。各冷冻组相比,菟丝子中剂量组精子形态正常率、膜完整率和SOD活性均高于其他冷冻组,MDA含量低于各冷冻组,但各指标仅表示与菟丝子低剂量组存在显著差异(P<0.05)。试验表明,适量的菟丝子提取物可对抗冷冻造成的膜损伤,提高精子SOD活性,降低MDA含量。     

Enhanced freezability of goat spermatozoa collected into tubes containing extender supplemented with bovine serum albumin (BSA)

The purpose of this study was to investigate the effects of semen collection into tubes containing extender supplemented with BSA on the cryosurvival of goat spermatozoa. Semen was collected from two goats into empty tubes or tubes containing 10 ml extender supplemented with 0, 0.1, 1, or 5% BSA, and the washed spermatozoa were frozen as pellets in egg yolk-trehalose extender with the addition of 0.04% SDS and 4% glycerol. Sperm motion parameters were evaluated after post-thawing and during a thermal resistance test. The acrosome status of frozen-thawed spermatozoa was also observed using FITC-PNA staining. In frozen semen that was collected into tubes containing extender supplemented with 5% BSA, the post-thawed spermatozoa exhibited a significant improvement in motion parameters and maintained high motility throughout incubation and acrosome integrity, as compared with semen collected into tubes containing extender supplemented with lower concentrations of BSA. In conclusion, semen collection into tubes with a large volume of extender containing high concentrations of BSA dramatically improves the motility and acrosome integrity of frozen-thawed spermatozoa. This suggests that the in vitro functional freezability of spermatozoa is abruptly modified by reducing contact with seminal plasma and by flash contact with BSA at ejaculation.     

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.     

Soya-lecithin in extender improves the freezability and fertility of buffalo (Bubalus bubalis) bull spermatozoa

Egg yolk is routinely used as a cryoprotectant in semen extenders. However, it may contain cryoprotective antagonists, and there are hygienic risks associated with its use. Proteins of plant origin, like soya-lecithin, lack these hazards. The aim of this study was to use soya-lecithin as a cryoprotectant in extender and to investigate its effects on in vitro quality and in vivo fertility of buffalo semen. Semen from three buffalo bulls was frozen in tris-citric extender containing 5.0%, 10% or 15% soya-lecithin or 20% egg yolk. Sperm motility, plasma membrane integrity and viability were assessed post-dilution, pre-freezing and post-thaw. In Post-dilution and pre-freezing, the values for motility, plasma membrane integrity and viability remained higher (p ≤ 0.05) in extenders containing 10% soya-lecithin and control compared with extender containing 5% and 15% soya-lecithin. However, motility, plasma membrane integrity and viability were higher (p < 0.05) in extender containing 10% soya-lecithin compared with control and extenders containing 5% and 15% soya-lecithin. Semen from two buffalo bulls was frozen in tris-citric extender containing either 10% soya-lecithin or 20% egg yolk. Higher (p < 0.05) fertility rate was recorded in buffaloes inseminated with semen containing 10% soya-lecithin (56%) compared with 20% egg yolk (41.5%). The results suggest that 10% soya-lecithin in extender improves the freezability and fertility of buffalo bull spermatozoa and can be used as an alternate to egg yolk in cryopreservation of buffalo semen.     

Assessment of intracellular Ca2+, cAMP and 1,2-diacylglycerol in cryopreserved buffalo (Bubalus bubalis) spermatozoa on supplementation of taurine and trehalose in the extender

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.     

Glutathione supplementation to semen extender improves the quality of frozen-thawed canine spermatozoa for transcervical insemination

The present study was conducted to evaluate whether supplementation of semen extender with glutathione (GSH) can maintain the quality of frozen-thawed canine spermatozoa. Eighteen ejaculates were obtained from 5 dogs and placed in extender (20% egg yolk, Tris, citric acid, lactose, raffinose, antibiotics and 6.5% glycerol) containing 0 (control), 2.5, 5, 7.5 or 10 mM GSH. The samples were cooled to 4 C and then frozen in liquid nitrogen vapor. Motility parameters of the sperm were evaluated at 0, 1, 2, 3, 4, 12 and 24 h after thawing. Sperm motility was higher in the 5 mM GSH group than in the control or 2.5 and 10 mM GSH groups; this effect was observed at 1 to 24 h after thawing (P < 0.05). The 5 mM GSH group had a higher sperm viability index at 12 and 24 h after thawing compared with the other groups (P < 0.05). Acrosome integrity, evaluated at 4 h after thawing, was greater in two of the GSH-treated groups (5 and 10 mM) compared with the control. Lipid peroxidation (LP) levels immediately after thawing were lower in the 5 and 10 mM GSH groups compared with the control, while those at 12 h after thawing did not differ significantly. Frozen-thawed semen in the 5 mM GSH group was used for transcervical insemination of 4 bitches, resulting in delivery of 5 puppies from 2 bitches. These results indicate that supplementation of semen extender with 5 mM GSH was effective in improving motility, longevity and acrosomal integrity and inhibiting LP levels in post-thaw canine spermatozoa, without any adverse impacts on full-term development after transcervical insemination.     

Evaluation of cryopreserved boar semen after supplementation sericin form silkworm (Bombyx mori) in semen extender

Boar cryopreserved semen is scarcely used for artificial insemination due to its quality which is largely reduced by membrane lipid peroxidation. This present study was designed to improve the post‐thawed boar semen quality by determining the optimal level of sericin supplementation (antioxidants) in semen extender. Five levels of sericin supplementation between 0% and 1% (w/v) were examined. Semen was frozen by the liquid nitrogen vapor method, thawed slowly at 5°C for 5 min, and used for the evaluation of sperm quality. The results indicated 0.5%–1% sericin supplementation was more effective on maintenance of sperm viability, acrosome integrity, and mitochondrial functions during freezing–thawing. Moreover, 0.75% sericin supplementation was most protective toward total sperm motility and sperm progressive motility. Additionally, 0.25%–0.75% sericin supplementation significantly suppressed increases in the index of lipid peroxidation. In conclusion, 0.75% sericin is recommended as an alternative component of the freezing extender to improve cryopreserved boar semen. However, further research using AI will be necessary to demonstrate that this indication can be applied to the production of offspring in the farms.     

High-speed centrifugation of extender of freeze-thaw boar semen

In semen cryopreservation, egg yolk is still widely used as a non-penetrating cryoprotectant. Much has been developed in the search for alternatives for this biological product. This work aimed to evaluate the processed egg yolk through ultracentrifugation and/or sonication in the cryopreservation of swine semen. Twenty-seven semen doses were purchased from a commercial boar stud and processed for cryopreservation using egg yolk lactose 11% (control) extender, processed using two different methods: high-speed centrifugation and sonication. Then, they were submitted to freeze-thawing protocol and were assessed for kinematic and cell structural parameters. Samples in which extenders underwent centrifugation had better results in velocity parameters, meanwhile those that only sonication was performed had poorest results in this parameter. The preservation of the membrane and mitochondria structure had better results when the diluent was only centrifuged in comparison with the other treatments. Therefore, centrifugation of extender containing egg yolk is important for better cryopreservation of swine semen.     

丁羟基甲苯抗猪精子氧化损伤作用

分别在稀释、离心猪精液中添加0.2、0.4、0.8、1.6 mmol/L丁羟基甲苯(Butylated hydroxytoluene,BHT),15℃保存,检验保存35、d后精子TMS、PMI和NAR(%)、测定MDA浓度;确定并选择最佳BHT浓度用于猪精液冷冻保存,检验解冻后TMS、PMI、NAR和Mt-MP(%)、测定MDA浓度。结果显示:BHT显著提高稀释精液、离心精液各项指标百分率(P0.05),且MDA浓度显著降低(P0.05),BHT最佳浓度分别为0.8、1.6 mmol/L;0.8 mmol/L BHT显著提高冷冻-解冻精液各项指标百分率(P0.05),且MDA浓度显著降低(P0.05)。结果表明,BHT能通过抑制精子质膜氧化损伤,提高猪精液保存效果。     

Effects of trehalose supplementation on the growth performance and intestinal innate immunity of juvenile chicks

1. Trehalose is composed of two molecules of D-glucose joined by an α,α-1,1 glucosidic linkage and has antioxidative and anti-inflammatory effects. The present study investigated the effect of feeding a trehalose-supplemented diet on the growth performance, as well as the oxidative status and the intestinal innate immunity of juvenile chicks.

2. A total of 16 d-old male broiler chicks were used in this study: two groups of 8 birds were fed on a 0% (control) or 0.5% trehalose-supplemented diet for 18 d.

3. The mean body weight of the trehalose group was significantly greater than that of the control group, but feed efficiency was not altered by feeding the trehalose-supplemented diet. No differences in the levels of lipid peroxidation in skeletal muscle, liver and plasma were observed between the control and trehalose-supplemented groups. The mRNA levels of interferon-γ, tumour necrosis factor-like ligand 1A, interleukin-10, NADPH oxidase 4 and inducible NO synthase were significantly reduced by the trehalose supplementation.

4. Our results suggest that dietary supplementation with trehalose after hatching may have beneficial effects on the growth performance of juvenile chicks, probably by improving their intestinal innate immunity.