Myeloperoxidase in Equine Semen: Concentration and Localization during Freezing Processing

Myeloperoxidase (MPO) is a pro-oxidant enzyme contained in and released by neutrophils during degranulation or after lysis. Post-thaw semen contains MPO, and concentration of this enzyme is associated with decreased motility. The aim of this study was to determine kinetics of MPO concentration during freezing, its origin, and its impact on frozen-thawed semen. Forty ejaculates were used. Semen was frozen using the classical freezing procedure. MPO concentrations were assayed in fresh semen, after centrifugation, and after cooling down to 4°C. Post-thaw MPO assay results and spermogram characteristics were determined. MPO immunocytochemistry was performed on 4 different ejaculates at each step of freezing procedure. MPO concentration increased after cooling down to 4°C and thawing compared with fresh semen. As temperature decreased, MPO was higher or tended to be higher in post-thaw poor quality samples. Nonsperm cells showed various degrees of MPO immunostaining and were observed as epithelial cells with nuclear pyknosis and keratinization. MPO immunostaining increased in medium and decreased in nonsperm cells during freezing. Our study shows that MPO concentration in equine semen increases when temperature decreases. We hypothesize that nonsperm cells present in fresh semen could release MPO.     

On Deep Freezing of Boar Semen: Investigations on the Effects of Different Straw Volumes, Methods of Freezing and Thawing Extenders

Contents: At the Bundesanstalt Wels tests with frozen-thawed boar semen in plastic straws were conducted. The influences of straw volume, method of freezing and thawing extender were investigated. The straw volumes of 1, 0 and 0, 5 ml showed significantly better thawing results in a preliminary trial than the 5, 0 ml Macrotub. When semen was frozen in a computerized freezer with automatic seeding, all tested straw. volumes gave significantly better results than the straws frozen in static N₂-vapor. A ready to use commercial extender was used for thawing with good results to simplify the handling of deep frozen semen for on farm insemination. In the main trial 60 ejaculates from 10 boars were frozen in 1, 0 ml straws in the computerized freezer. Three in vitro parameters for fresh semen (motility, osmotic resistance and keeping quality under standard conditions) and two parameters for thawed semen (motility and percentage of sperm with normal apical ridge) were recorded and correlated. The osmotic resistance test proved to be well suited as means of predicting the fitness of an ejaculate for deep freezing, but the other two fresh semen parameters showed poor correlation with the parameters for thawed semen. From the parameters for thawed semen a freezing score was derived as a measure of the freezability of single ejaculates and boars. A preliminary insemination trial gave satisfying farrowing rates. Inhalt: Zur Tiefgefrierung von Ebersamen: Untersuchungen zum Einfluß von verschiedenen “Straw”-Volumina, Einfriewerfahren und Auftaubedingungen Ander Bundesanstalt Wels wurden Tiefgefrierversuche mit Eberspermain Kunststoffpailletten durchgeführt. Die jeweiligen Einflüsse von Paillettenvolumen, Gefrierverfahren und Auftauverdünner wurden untersucht. In Vorversuchen erwiesen sich die Paillettenvolumina 1, 00 und 0, 5 ml gegenüber den 5,0 ml Makrotüb hinsichtlich Kopfkappenintegrität und Auftaumotilität signifkant überlegen. Die Auftauergebnisse der im computergesteuerten Freezer mit automatischem Seeding eingefrorenen Proben waren für alle untersuchten Paillettengröβen signifikant bis hoch signifikant besser, als die Werte der im statischen Stickstoffdampf eingefrorenen Proben. Als Auftauverdünner wurde ein handelsüblicher Fertigverdünner gewählt um eine besonders für den Eigenbestandsbesamer wichtige einfache Handhabung der TG-Besamung zu gewährleisten. Im Hauptversuch wurden 60 Ejakulate von 10 Ebern verwendet und in 1, 0 ml Pailletten im programmierbaren Freezer eingefroren. Drei Frischsamenparameter (Motilität, osmotische Resistenz und Haltbarkeit unter Laborbedingungen) und zwei Auftausamenparameter (Motilität und Kopfkappenintegrität) wurden erhoben und korreliert. Dabei enwies sichder osmotische Resistemtest als für die Beurteilung von Frischsperma hinsichtlich TG-Eignung gut geeignet, während die beiden anderen Frischsamenparameter keine bzw. nur schwache Korrelation zu den Auftauergebnissen aufwiesen. Aus den Auftausamenparametern wurde eine “Einfrierbarkeitszahl” als Maβ für die Eignung des Spermas zur Tiefgefrierkonservierung der einzelnen Eber bzw. Ejakulate erstellt. Dabei enwies sich der osmotische Resistenztest als für die Beurteilung von Frischsperma hinsichtlich TG-Eignung gut geeignet. Bei einem orientierenden Besamungsversuch wurden zufriedenstellende Abferkelraten erzielt.     

Identification of Apoptotic Bodies in Equine Semen

Apoptosis in the testis is required to ensure an efficient spermatogenesis. However, sometimes, defective germ cells that are marked for elimination during this process escape elimination in the testes, giving rise to ejaculates with increased percentages of abnormal and apoptotic spermatozoa and a high percentage of apoptotic bodies. Apoptosis markers in the ejaculate have been associated with low fertility, either in animals or humans. Therefore, the goal of this study was to investigate whether fresh equine semen contains apoptotic bodies [initially named Merocyanine 540 (M540) bodies] and to study the relationship between the quantity of these bodies and cell concentration, the volume of ejaculate, viability and motility. Moreover, we also studied whether the presence apoptotic bodies in fresh semen was related to the resistance of the stallion spermatozoa to being incubated at 37°C or being frozen and thawed. Fresh equine semen was stained with fluorescent dyes such as M540 and Annexin‐V. Active Caspase 3 was studied in fresh semen through Western blotting and immunofluorescence with a specific antibody. Sperm kinematics was assessed in fresh, incubated and thawed samples using computer‐assisted semen analysis, and viability was evaluated with the LIVE/DEAD Sperm Viability Kit. Overall, our results demonstrate for the first time the presence of apoptotic bodies in equine semen. The quantity of apoptotic bodies was highly variable among stallions and was positively correlated with Caspase 3 activity in fresh samples and negatively correlated with the viability and motility of stallion spermatozoa after the cryopreservation process.     

狐精液冷冻技术研究

对狐精液进行冷冻试验，筛选出１号和３号两种稀释液，冷冻精液颗粒剂量为０．１ｍｌ，解冻温度４２－４５℃，冷冻方法采用纱网和氟板漂浮法均可。     

The Use of Cefquinome in Equine Semen Extender

Antibiotics are commonly used in equine semen extender for conservation, if semen has to be stored cooled for a maximum of 48 hours or frozen, to eliminate pathogenic or potentially pathogenic bacteria from semen and reduce the risk of postmating endometritis. Little is known about the effect of antibiotics on spermatozoa when semen is stored over a longer period. Cefquinome, a broad spectrum antibiotic and fourth-generation cephalosporin, has been proven to be a powerful drug for the treatment of endometritis and mastitis in different species. Recently in equine studies, it was found to localize in high concentrations in the endometrium. Therefore, cefquinome was used as the antibiotic in semen extender and compared with a commercial semen extender containing gentamicin for effects on motility and membrane integrity of spermatozoa. During the breeding season, ejaculates from nine light horse stallions were collected and half of each ejaculate was stored for 48 hours in modified Kenney type semen extender containing either cefquinome or gentamicin. At 0, 24, and 48 hours, aliquots (20 μL) of the stored semen were evaluated for (progressive) motility and membrane integrity, as well as for various motility parameters by computer assisted sperm analysis. No differences (P > .05) were found in total motility or progressive motility between extenders at any time point. However, there were differences (P < .05) in velocity parameters, although the effect of velocity parameters on fertility is not clear. In general, semen parameters after storage in non-fat dried skim milk semen extender containing cefquinome are comparable with those after storage in semen extender containing gentamicin. The wider spectrum of bactericidal activity possessed by cefquinome may prove to be beneficial in some cases.     

猪精液冷冻技术试验

从稀释液和解冻液的筛选，平衡时间、平衡温度、冷冻剂型的选择等方面进行试验。试验结果：猪精液冷冻后活率为３０％－６０％；解冻后的复苏率为５１．４２％－５８．７２％；保存３０天的冻精与保存３６０天的冻精受胎率无明显差异（Ｐ＞０．０１）；冻精保存期一年以上；输精受胎率达６３．６４％（６０％－６６．６６％），平均窝产仔６．１头。     

猪精液冷冻技术的研究

以解冻后的精子活率、活力、质膜完整率、顶体完整率和人工授精结果为判定指标 ,比较了几种冷冻稀释液、解冻液及冷冻 -解冻程序对猪精液冷冻的效果 ,并对所筛选出的最佳稀释液和冷冻程序做了改进。结果如下 :(1) 号稀释液冷冻解冻后的精子活力 (32 .4± 7.3) %、活率 (4 2 .2± 3.2 ) %、顶体完整率 (6 2 .3± 0 .8) %和弯尾率 (4 2 .6± 7.5 ) %均显著高于 、 、 号稀释液 (P<0 .0 5 )。 (2 )在 号稀释液中添加 0 .5 %、1%和 2 %的 O.E.P(氨基 -钠 -十二烷硫酸酯 )使精子活率提高 5 %、弯尾率提高 6 %、顶体完整率提高近 10 % ,与对照组相比差异显著 (P<0 .0 5 )。 (3)应用改进的稀释液 ( 液加 1% O.E.P) ,细管法比颗粒法冷冻精子活率提高近 7个百分点 ,活力提高 6个百分点 (P<0 .0 5 )。(4 )室温预平衡 4h的精子活力和活率都比对照组 (0 h)有显著提高 (P<0 .0 5 ) ,而预平衡 2、6 h的精子活力和活率与对照组差异不显著 (P>0 .0 5 )。 (5 ) 号解冻液解冻后精子活力 (4 2 .9± 2 .6 ) %显著高于 、 、 号解冻液 (P<0 .0 5 )。 (6 )用 5 0℃水浴解冻精子的活力 (4 6 .3± 2 .6 ) %显著高于 39℃ (4 2 .9± 2 .6 ) %和 70℃水浴 (4 1.1± 5 .7) %解冻的精子活力 (P<0 .0 5 )。 (7)精清和 号解冻液     

猪精液冷冻技术研究进展

本文综述了猪冷冻精液的国内外发展简史，对冷冻保存机理进行了简要阐述，并从冷冻保存稀释液、冷冻保护剂及其浓度、诱发结晶和解冻等方面阐述了影响猪冷冻精液的因素，指出了目前在猪精液冷冻理论和实践中的存在问题，并针对这些问题提出了一定的解决办法。     

牛精液冷冻机理的探讨

为了深入探讨精液冷冻理论,突破传统”结晶态”和“玻璃态”学说束缚。从近年来牛精液冷冻液固两相变化研究成果出发,基于非线性耗散结构理论对牛精液冷冻机理进行深入探讨。现有研究结果表明,精液冷冻过程属于远离平衡态开放系统体系,通过与外界交换物质和能量,自发产生自组织现象,达到新的平衡状态,形成耗散结构。用耗散结构理论方法研究精液液固两相运动规律,突破了精液冷冻理论研究的传统框架,更好地说明了精液冷冻机理。     

猪精液冷冻技术研究进展

本文综述了猪冷冻精液的国内外发展简史,对冷冻保存机理进行了简要阐述,并从冷冻保存稀释液、冷冻保护剂及其浓度、诱发结晶和解冻等方面阐述了影响猪冷冻精液的因素,指出了目前在猪精液冷冻理论和实践中的存在问题,并针对这些问题提出了一定的解决办法.     

猪精液冷冻技术研究

手握法采集约克种公猪(12月龄)精液,于37℃离心后弃去精清,收集浓缩段富含精子部分,采用液氮熏蒸法制作颗粒冻精。通过对不同稀释液及冷冻保护剂进行筛选研究,结果表明,Ⅶ号稀释液优于其他6种稀释液(P<0 05);甘油为较佳的冷冻保护剂(P<0 01),其适宜浓度为2%;干解冻效果优于湿解冻,其适宜温度为40～45℃,解冻后精子活率达0 46～0 52;稀释液中添加安钠咖可有效延长精子的冻后存活时间(P<0 01)。     

胆固醇对山羊精液冷冻效果的影响

研究了胆固醇对山羊精液冷冻的影响。结果表明，胆固醇不影响冷冻后精子的活力，但影响精子的项体，添加胆固醇后，精子顶体部分脱落的比例增高，但全部脱落的比例降低。     

乌苏里貉精液冷冻技术研究

为探索乌苏里貉精液冷冻技术,通过试验,筛选出了适合于乌苏里貉精液的鲜精稀释液和冷冻保护液配方,摸索出了乌苏里貉精液的冷冻程序,包括降温、平衡和预冷冻等各技术环节以及冷冻精液的最适解冻温度,解冻后在生物显微镜下观察,精子活力均在4~5级。     

大额牛冷冻精液技术的研究

本文对大额牛的射精量、精子密度、精子活力等指标进行了测定,同时对大额牛精液的冷冻稀释液、制作程序进行了较为系统的研究。结果得出,大额牛在人工饲养条件下,公牛的射精量为4.92±1.50mL、精子密度为16.79±4.5亿/mL、原精活力0.63±0.078;冷冻精液解冻活力平均可达0.3875±0.0426、冻精解冻后顶体完整率平均52.74%±5.88%,畸形率为12.95%±3.18%,精子复苏率为59.63%±3.67%,其他指标与一般黄牛基本一致。     

辽宁绒山羊细管冷冻精液研究

本实验研究了辽宁绒山羊细管冷冻精液的稀释液及制作工艺。结果表明:离心洗涤去精清可以提高冷冻-解冻后的精子活率,与不去精清的对照组相比差异显著(P<0.05);以等体积乙二醇替代甘油作防冻剂制作的细管冷冻精液,解冻后的精子活率和顶体完整率显著(P<0.05)高于甘油作防冻剂的对照组。实验还证明,含Tris的柠檬酸盐缓冲液对提高冷冻后精子活率与顶体完整率具有良好的作用。     

红腹锦鸡精液冷冻稀释液配方的筛选

为加强濒危珍稀动物种质资源的保护,开展了濒危珍稀禽类—红腹锦鸡的人工授精研究。2005年5月26日~6月8日,对8只红腹锦鸡用手按摩其背、尾部采精12次。初测其精液品质,结果表明,采精量平均(0.114±0.016)mL(0.01~0.2 mL),每毫升精液中精子平均3.2亿个(3.0~3.3亿),活力9级以上,pH值6.5,偏酸性,淡乳白色(半透明似冲熟的藕粉),微腥。鲜精分别加11%蔗糖—卵黄稀释液(3号液);11%蔗糖—0.1%柠檬酸三钠—卵黄稀释液(5号液);5%葡萄糖—卵黄稀释液(8号液)。精子活力达8~9级。用3%柠檬酸三钠—卵黄稀释液(2号液)稀释,精子活力2级。冷冻时,用11%蔗糖溶液100 mL中加16 mL鲜卵黄,加5 mL甘油,配制的3号冷冻稀释液稀释,解冻后,精子活力达4级。优于试验中选拟的其它配方(加入5 mL甘油的5号冷冻液,解冻后精子活力为3级;加入5 mL甘油的8号冷冻液,解冻后未见活的精子)。如果冷冻稀释液中甘油改为6 mL,则解冻后精子全部死亡。     

家禽精液冷冻保存技术的研究进展

家禽精液冷冻保存技术对提高家禽繁殖率，加速良种选育和扩繁起着重要作用，因为母禽生殖细胞保存受其先天的限制(在卵黄上)，无法象哺乳动物取其卵母细胞或胚胎进行良种保存和繁殖，故家禽育种的繁殖除了扩大群体外，雄性禽类精细胞的保存和利用是最有效的方法；若能将优良种禽的精液加以冷冻保存，即可充分利用良种最佳阶段的遗传性能，大大提高遗传进展。