提高种公羊精液质量的有效措施

种公羊射精量和精液品质主要取决于遗传特性、饲养管理和采精技术。射精量和精液品质将关系到冻精的生产量、需配种母羊的受胎率和农民的经济效益。因此,种公羊饲养管理措施和采精方法就至关重要。90年代中期以来,随着波尔山羊的批量引进,山羊冷冻精液生产技术在我国得到了很快的普及和发展。由于一只优秀波尔山羊种羊的价格很高,培养一头优秀种公羊要付出很大的代价,因此对种公羊进行科学饲养管理就显得十分重要。     

不同品种种公羊精液品质的比较

选择无角道塞特、萨福克、特克塞尔、夏洛莱等4个不同品种的良种肉羊种公羊共40只．按常规方法采集精液,并对精液品质进行分析比较。结果表明4个不同品种种公羊的射精量、精子密度、鲜精活率、畸形率、顶体完整率都有差异。但是射精量、鲜精活率、畸形率3个指标之间的差异不显著（P〉0．05）,而密度与顶体完整率两个指标间的差异显著（P〈0．05）。4个品种中萨福克种公羊的精子密度最高,其次为特克塞尔和夏洛莱种公羊,最低的为无角道塞特种公羊。其中萨福克种公羊的精子密度显著高于特克塞尔、夏洛莱和无角道塞特种公羊（P〈0．05）。4个品种中无角道塞特种公羊的精子顶体完整率最高,其次为特克塞尔和萨福克种公羊,最低的为夏洛莱种公羊。其中无角道塞特种公羊的精子顶体完整率显著高于夏洛莱种公羊（P〈0．05）。     

提高种公羊冷冻精液品质的综合措施

贵州省家畜冷冻精液站始建于1976年.2000年以后开始进行波尔山羊冷冻精液的生产,我站紧紧围绕提高波尔公羊的冻精品质,形成了一套较为系统、有较强针对性和操作性的管理和生产措施,现总结为如下几点.     

辽宁绒山羊公羊精液相关技术参数测定结果

通过相关测定,统计出辽宁绒山羊公羊在不同条件下精液相关技术参数数值的大小和变化规律,为生产和研究提供参考数据。     

不同品种种公羊精液品质的比较

选择无角道塞特、萨福克、特克塞尔、夏洛莱4个品种的良种肉羊种公羊共40只,按常规方法采集精液,并对精液品质进行分析比较。结果表明,4个品种种公羊的射精量、精子密度、鲜精活率、畸形率、顶体完整率都有差异,但是射精量、鲜精活率、畸形率3个指标之间的差异不显著(P>0.05),而密度与顶体完整率两个指标间的差异显著(P<0.05)。4个品种中萨福克种公羊的精子密度最高,其次为特克塞尔和夏洛莱种公羊,最低的为无角道塞特种公羊,其中萨福克种公羊的精子密度显著高于特克塞尔、夏洛莱和无角道塞特种公羊(P<0.05)。4个品种中无角道塞特种公羊的精子顶体完整率最高,其次为特克塞尔和萨福克种公羊,最低的为夏洛莱种公羊,其中无角道塞特种公羊的精子顶体完整率显著高于夏洛莱种公羊(P<0.05)。     

“强精散”提高公羊精液品质的研究

选用２０只种公羊，随机均分为试验、对照两组。正式开始配种时试验组种公羊按每只每天１０ｇ饲喂“强精散”，连用２５ｄ。结果表明，公羊饲喂“强精散”后９～１６ｄ、１７～２５ｄ内精子活力、精子存活率、精子密度、射精量两组间差异极显著（Ｐ＜０．０１），停药后８天内精子活力、精子存活率、精子密度、射精量两组间差异显著（Ｐ＜０．０５）。但对精子云雾状、ｐＨ值和精子畸形率则无明显作用。     

应用721型分光光度计测定公羊精液密度的试验

1试验目的及意义 随着科技的发展,新型的仪器不断在畜牧业生产中应用.     

如何检查公羊精液品质

羊品种改良生产中,检查精液品质十分必要。公羊精液品质不良,或在稀释过程中品质的变化都决定能否用来输精、能否达使母羊受精所需要的标准,都会造成很多母羊不孕,因而对怀疑精液品质不良的公羊,应按人工授精对精液品质的要求标准,进行详细检查。     

Influence of methionine and dithioerythritol on sperm motility, lipid peroxidation and antioxidant capacities during liquid storage of ram semen

The aim of this study was to investigate the effects of methionine and dithioerythritol, added to the Tris extender, on ram sperm motility and LPO (lipid peroxidation) and antioxidant capacities during liquid storage up to 72 h at 5 °C. Ejaculates collected from five Merino rams, were evaluated and pooled at 37 °C. This study included two experiments. In experiment 1, each pooled ejaculate was divided into four equal aliquots and diluted (37 °C) with the base extender, containing 0 (control), 1, 2 and 4 mM methionine, at a final concentration of approximately 4 × 10⁸ sperms/ml (single step dilution), in a 15-ml plastic centrifuge tube. In experiment 2, dithioerythritol, at concentrations of 0 (control), 0.5, 1 and 2 mM, was used as an additive in the extender, and the procedure explained above was applied for the division of aliquots and the dilution of semen. Diluted semen samples were kept in glass tubes and cooled from 37 to 5 °C in a cold cabinet, and maintained at 5 °C. Sperm motility and LPO and total glutathione (GSH) and glutathione peroxidase (GPx) capacities were determined at 5 °C for periods of 0, 24, 48 and 72 h of liquid storage.The extender supplemented with 1 mM methionine led to higher motility percentages (77.0 ± 1.2%), in comparison to the control group (66.0 ± 4.9%), during 72 h of liquid storage (P < 0.05). As regards dithioerythritol, it did not statistically improve the motility rates for any of the storage times at 5 °C. In biochemical assays, differences in LPO levels between the groups with antioxidants and the control groups were not statistically significant. Compared to the control group, no significant difference was observed in GSH and GPx activities following the addition of methionine, during 72 h of storage. Total GSH and GPx activities did not increase significantly upon supplementation with 0.5 and 1 mM of dithioerythritol, compared to the control group, at any of the time points (P > 0.05). Dithioerythritol at 2 mM led (P < 0.01) to elevating GSH activity, compared to the control group, during 72 h of liquid storage. GPx activity was approximately 10 times higher for 2 mM of dithioerythritol (P < 0.001), compared to that of the control group at all time points.The question regarding the sustainability of sperm survival, LPO and antioxidant capacities following liquid storage of semen remains unanswered. Further studies are required for a better understanding of the biochemical changes and to obtain more information on the determination of lipid peroxidation and antioxidant capacities during cooled storage of ram semen.     

稀释液渗透压对绵羊精液冷冻效果的影响

本试验对绵羊冻精采用两次稀释时,从调整Ⅱ液中葡萄糖含量和降低甘油浓度两方面,改变稀释液的渗透压,测定冻精效果。先增减糖的比例,配制9-2(对照), 84-1和84-2等试验组,其稀释Ⅱ液渗透压1191,1026、1499mmol/kg,获冻精情期产羔母羊率61.69, 63.31, 54.55(P<0.05)。随后, 以84-1为对照,降低甘油浓度,设3个试验组,即87-2,88-1和88-1a,渗透压相应为747,456,463mmol/kg,冻精情期受胎率1987年84-1,87-2为65.37,67.37;1988年87-2,88-1,88-1a为63.16,62.50,46.55(P<0.05)。试验说明,绵羊冻精采取2次稀释法,第Ⅱ液以4％甘油,渗透压为747mmol/kg时,冻精效果最佳。     

对塔什库尔干羊种公羊体重、体尺常规参数的研究

本文对塔什库尔干羊周岁和成年种公羊的体重、体尺指标的平均数（x）、标准差（s）、最小值、最大值进行了统计分析。结果表明,塔什库尔干羊周岁种公羊的平均体重（x）=（41．54±5．4：91）kg（n=1143）,最小值=35kg、最大值=75kg;塔什库尔干羊成年种公羊的平均体重（x）=（52．92±8．537）kg（n=393）、最小值=35kg、最大值=93kg。体重与体高、体长、胸围及管围呈正相关关系,差异极显著（P〈0．01）;其中体高与体长之间的正相关关系最大（r=0．661）,存在极显著差异（P〈0．01）。     

Scrapie resistance and production traits in Rambouillet rams: ram performance test 2002-2006

Sheep possessing alleles for the prion protein with glutamine (Q) or histidine, both reported as Q, at codon 171 are highly susceptible to scrapie. Incidence of scrapie infection is rare when animals possess at least one allele for arginine (R) at codon 171. The current USDA APHIS scrapie eradication program utilizes genotyping for alleles that confer resistance to scrapie. Although it has not been a criterion of registration, genotyping has been utilized in the University of Wyoming Ram Performance test since 2002. Performance test records from 2002 to 2006 (n=518) were analyzed to determine if any production loss or benefit was associated with scrapie resistance in rams. Performance of rams with scrapie resistant genotypes was equal to or better than scrapie susceptible rams. Based on test performance as an acceptable indicator of sire superiority, selection for rams with scrapie resistant genotypes should not negatively impact flock performance.     

Effects of reduced glutathione supplementation in semen freezing extender on frozen-thawed bull semen and in vitro fertilization

During cryopreservation, spermatozoa may suffer cold and cryo-induced injuries ―associated with alterations in cell defense systems― that are detrimental to their function and subsequent fertility. This study aimed to determine the efficacy of supplementing the semen freezing extender with the antioxidant reduced glutathione (GSH) in cattle. Semen was collected from four bulls and diluted in a freezing extender supplemented with or without GSH (0, 1, 5, and 10 mM) before the cooling step of the cryopreservation process. After thawing, the quality of the frozen-thawed semen was investigated for motility, viability, acrosomal and DNA integrity, and subsequent embryo development after in vitro fertilization of bovine oocytes. Additionally, semen from one of the bulls was used to analyze semen antioxidative potential, sperm penetration into oocytes, male pronucleus formation rate, and embryo DNA integrity. The sperm quality varied among bulls after GSH supplementation. One bull had decreased sperm total motility, and two bulls had decreased sperm DNA integrity. GSH supplementation had positive effects on embryo development for three bulls. Two of them showed both improved cleavage and blastocyst formation rates, while the other one only showed an improved cleavage rate. We observed positive effects on early male pronucleus formation and no negative effects on DNA integrity and cell number in blastocyst stage embryos. Although the effect varies depending on individual bulls and GSH concentration, GSH supplementation in semen may improve in vitro embryo production from frozen semen.     

中草药添加剂对种公羊精液品质和耐冻性的影响

为探索中草药添加剂对种公羊精液品质的影响,用当归(Radix angelicae sinensis)、党参(Radix codonop sis)、黄芪(Radix astrag ali)、淫羊藿(Herba epimedii)、菟丝子(Semen cuscutae)等19味中草药复方配伍作饲料添加剂,按每头种公羊饲料量1%的比例饲喂3周,对种公羊的性反应和精液品质进行分析研究。结果表明:饲喂中草药添加剂后公羊性反应时间显著缩短;射精量、精子密度较对照显著和极显著提高;每次射精有效精子数达到61.64×109,比对照组增加2.36倍,差异极显著(P<0.01);精子头部畸形率较对照组降低8%(P<0.05);饲喂1周对精液质量有明显改善,饲喂3周至停药1周后可延缓精子质量下降的速度;且饲喂后种公羊的冻后精子活率和精子复苏率较对照和饲喂前显著提高(P<0.05),分别增加38.7%和28.9%。该复方中草药添加剂适用于高频度采精种公羊,可改善公羊的精液品质,提高人工授精过程中精液保存质量,有利于进一步发挥优良公羊的种用价值。     

Carcass characteristics of Awassi ram lambs slaughtered at different weights

Thirty Awassi ram lambs were used to study the effects of slaughter weight on carcass characteristics. Lambs were slaughtered at three different live weights (20, 30, and 40 kg). Empty body weight, hot and cold carcass weights and non-carcass components increased (P < 0.001) at a steady rate between all slaughter weights. Body length, leg length, maximum shoulder width, width behind shoulders and gigot width increased (P < 0.001) as slaughter weight increased from 20 to 40 kg. Linear dimensions measured on the surface of the M. Longissimus also increased (P < 0.001) with increasing slaughter weight. The ratio between width and depth of the longissimus muscle decreased (P < 0.01) at a steady rate between 20 and 40 kg indicating that the muscle increased more in depth than width. Dressing-out percentage was higher (P < 0.001) for lambs slaughtered at 30 kg live weight compared to other weights. Total lean and total bone decreased (P < 0.05) as a percent of cold carcass weight while total fat, subcutaneous and intermuscular fat percentages increased (P < 0.05) with increasing weight. Subcutaneous fat percentage was not affected by increasing body weight between 20 and 30 kg. Intermuscular fat percent was higher in all cuts except the leg where subcutaneous fat % was higher. Muscle to bone ratio increased (P < 0.001) while muscle to fat ratio decreased (P < 0.001) with increasing body weight in the four major cuts and the whole carcass. In conclusion, slaughtering Awassi ram lambs at weights up to 30 kg resulted in higher dressing-out percentage and better carcass characteristics than ram lambs slaughtered at heavier weights.     

Effects of seasons on some semen parameters and bacterial contamination of Awassi ram semen

The objectives of the present study were to determine the effects of season on some semen parameters and bacterial contamination of Awassi ram semen. Semen samples from six mature Awassi rams were used in this study. Semen collection was performed with artificial vagina every week, from September 2009 to October 2010. Volume, sperm concentration, mass motility, individual motility, percentage live sperm and sperm abnormalities were evaluated. Moreover, determination of viable bacterial count of the rams was also recorded weekly. Higher (p < 0.05) semen volume in the hot summer and spring months was observed of August (1.55 ± 0.08 ml) and March (1.27 ± 0.15 ml). Sperm concentration was highest (p < 0.05) in the breeding season (late summer to early autumn) of September (4.21 ± 0.86 × 10(9) sperm/ml). Sperm individual motility and percent of live sperm observed in August (summer) and May (end of spring) when the environmental temperature started to increase were recorded highest values and differed significantly (p < 0.05) from December and January (winter). The highest value of the mean sperm acrosomal defects (13.33 ± 0.63%) was recorded in December. The highest value of the mean viable bacterial count (138.3 ± 21.6) was recorded in July (summer). A significant decrease (p < 0.01) in the mean viable bacterial count was observed from the middle of winter towards the end of spring. The lowest bacterial count was noted in January (60.5 ± 2.98). It could be concluded from the results of the present study that there is an effect of season on ram semen quality, and summer high temperature in northern Iraq has no effect on Awassi ram semen. There is a significant effect of season on bacterial count on Awassi ram semen.     

白藜芦醇对松辽黑猪精液冷冻的影响

试验旨在评价白藜芦醇(resveratrol,Res)对松辽黑猪公猪精液冷冻的影响。试验分为5组,分别为对照组(不添加Res)和Res处理组(在冷冻基础液中分别加入25μM、50μM、100μM、200μM浓度的Res)。采用手握法采集松辽黑猪精液,用5种冷冻基础液稀释,在25℃平衡1 h,17℃平衡2 h,4℃平衡3 h后灌装于0.5 mL细管中,在液氮上方3 cm处熏蒸10 min,保存在液氮罐中30 d后进行检测。样本解冻后分别检测精子活力、谷胱甘肽过氧化物酶(GSH-Px)活性、质膜完整性、过氧化氢酶(CAT)活性、顶体完整性、线粒体活性、活性氧簇(ROS)水平、DNA完整性、超氧化物歧化酶(SOD)活性以及丙二醛(MDA)水平。结果显示:与对照组相比,冷冻基础液中添加50μM Res可以显著提高冻融后精子的活力、SOD活性、质膜完整性、CAT活性、线粒体活性、GSH-Px活性、顶体完整性(P0.05);可以显著降低精子ROS水平和MDA水平(P0.05);添加Res对DNA完整性未表现出具有显著影响(P0.05)。结论:猪精液冷冻前添加Res可改善冻融后精子质量,添加量50μM效果最佳,但Res是否可以改善公猪冷冻精液的体外受精及人工授精能力,有待于进一步的研究。