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41.
Artificial insemination (AI) can help to avoid inbreeding and genetic degeneration for sustaining genetically healthy populations of endangered species in captivity. Collection of a sufficient quantity of viable sperm is an essential first step in the AI process. In the present study, we examined the effects of frequent electroejaculation on semen characteristics in a Siberian tiger. We collected semen in all 17 trials during 6 breeding seasons (6 years). The mean number of sperm and the percentage of motile sperm were 294.3 ± 250.2×106/ejaculate and 82.4 ± 11.4%, respectively. The number of motile sperm tended to increase during frequent electroejaculation in the same breeding season. Semen collection by electroejaculation can be performed effectively up to the fourth sequential ejaculate, which contained the most sperm in the study. In conclusion, frequent collection of sperm by electroejaculation from tigers may be effective for collection of a large number of motile sperm.  相似文献   
42.
[目的]为了提高萨福克羊精液低温液态保存的效果。[方法]用葡萄糖、柠檬酸钠、乳糖、卵黄为主要成分配制了5种萨福克羊精液稀释液,分别4、81、21、6倍稀释精液并5℃保存,通过观测精子存活时间、有效存活时间、生存指数等指标,筛选出精液保存时适宜的稀释液、渗透压、pH值及稀释倍数。[结果]4倍稀释不利于精液保存,8、121、6倍稀释精液保存效果好(P<0.01),结合母羊受胎率稀释保存倍数以8倍为宜;以葡萄糖3.0 g、柠檬酸钠2.0 g、卵黄10 ml为主要成分的稀释液保存效果优于其他4种稀释液(P<0.05)。稀释液pH值和渗透压与精液越接近保存效果越好。[结论]调整稀释液成分、稀释倍数、pH值、渗透压,可以提高萨福克羊精液低温液态保存效果。  相似文献   
43.
为了考察人参对梅花鹿精液品质及产仔率的影响,将繁殖准备期的健康雄性梅花鹿32头随机分为4个处理(T1~T4),每个处理8头,T1~T4为基础精料中分别添加人参0、0.4、0.8、1.6 g/kg。结果表明:日粮中添加人参,显著提高了梅花鹿的采精液量、精子活力、精子抗力、精子密度、精子存活时间、精子存活指数(P<0.05);显著降低了精子畸形率(P<0.05);对精液pH值的影响没有显著差异(P>0.05);提高了采精成功率和产仔率;精液云雾状T3处理组最明显,精液色泽均为乳白色。梅花鹿精料中添加人参0.8 g/kg时,对提高梅花鹿精液品质和产仔率效果最好,有利于鹿的繁育。  相似文献   
44.
In the past four decades there have been tremendous changes in equine reproduction. Most breeds now allow the use of artificial insemination with fresh, cooled and frozen semen. Artificial insemination has many advantages for the breeder, in particular the control of bacteria through the use of semen extenders containing antibiotics. Deposition of sperm in small volumes onto the uterotubal junction has allowed the use of relatively low numbers of sperm. Intracytoplasmic injection of sperm into oocytes allows older, subfertile stallions to be used as breeding stallions. Advances in mare reproduction have included developing tools for hastening the onset of the breeding season. Other advances include embryo transfer, oocyte collection and transfer, and cloning. The acceptance of reproductive technology depends on the success of the technology, the attitude of the breeders/veterinarians, and the cost/benefit ratio to the industry and breed registry.  相似文献   
45.
[目的]探讨了不同pH值、渗透压的稀释液对关中奶山羊冻精品质的影响,以确定关中奶山羊精液最佳保存与冷冻效果。[方法]通过显微检测在不同pH值、渗透压的稀释液处理对降温前、平衡后与解冻后的精子的活率、复苏率、精子顶体完整率、精子畸形率及精子冻后存活时间等指标进行评估。[结果],关中奶山羊精液稀释液pH值为7.3时,降温前、平衡后与解冻后的精子活率最高,分别达到0.742±0.011%、0.645±0.011%、0.489±0.012%;冻后活率、复苏率及解冻后顶体完整率分别达到0.431±0.009%、63.1±0.427%、65.7±2.018%;精子存活时间在降温前、平衡后及解冻后分别达到12.50±0.141h、11.96±0.186h、11.61±0.753h,冻后 8 h 活率0.52±0.014%;当渗透压为Δ0.754℃时,其精子的保护效果最佳,降温前、平衡后与解冻后的精子活率分别达到0.752±0.045%、0.671±0.024%、0.649±0.036%;冻后活率、复苏率及解冻后顶体完整率分别达到0.481±0.019%、63.6±0.377%、69.9±1.068%;精子存活时间在降温前、平衡后及解冻后分别达到11.82±0.165h、11.94±0.145h、11.70±0.753h,冻后 8 h 活率达到0.43±0.033%。[结论]关中奶山羊精液稀释液最合适的pH值是7.3,最佳渗透压为Δ0.754℃,这一结果对奶山羊稀释液配方优化提供了一定的理论指导。  相似文献   
46.
Rabbit farmers and insemination centres have established new requirements relating to males (genetic, nutritional and environmental factors) and rabbit insemination techniques. The aim of this study was to evaluate buserelin acetate on the reproductive performance of nulliparous, multiparous lactating and multiparous non-lactating does inseminated on three commercial farms. Two thousand two hundred and three commercial crossbred does belonging to three commercial farms were inseminated with pooled semen from males of two selected meat lines; R line (UPV rabbit selection centres, Spain) in farms 1 and 2, and PS Hyplus 59 line (Grimaud Frère, France) on farm 3. Ejaculates from 12–20 males from each line were pooled and diluted to twelve million sperm per millilitre by adding TRIS–citrate-extender. Diluted semen from each male line was split into two fractions, the first without buserelin acetate added to semen (Control group) and the second fraction was supplemented with 10 μg of buserelin acetate per millilitre (Buserelin group). Receptive females (red colour of vulvar lips) were inseminated with 0.5 mL using a standard plastic curved pipette. Artificial insemination with semen extended with buserelin resulted in lower pregnancy and kindling rates irrespective of the physiological status of females or the farm (78.7% and 76.0% vs 85.8% and 83.4%, buserelin extender group and control respectively, P < 0.01), although does from both treatment groups had a similar litter sizes (10.4 and 9.6 total and alive born, respectively). This study opened up new prospects for changing rabbit insemination procedures.  相似文献   
47.
试验选用海兰褐父母代蛋种公鸡32只,随机分为2组,每组2个重复。在日粮中,分别添加Omg/kg和667mg/kg抗应激剂,以提高种鸡热抗应激的能力。研究在夏季高温、高湿的生产条件下。以生产成本为参考因素时,抗应激剂对蛋种公鸡采食量和精液品质的影响。试验结果表明:日粮中添加抗应激剂对种公鸡采食量、精液量、精子活力均有不同程度的提高和改善。  相似文献   
48.
The objective of this study was to compare semen parameters and embryo recovery rates of cooled stallion semen extended with INRA 96 or BotuSemen Gold. In experiment 1, 45 ejaculates from nine mature stallions were collected, assessed, and equally split between both extenders and then extended to 50 million sperm/mL. Then, the extended semen was stored in three passive cooling containers (Equitainer, Equine Express II, and BotuFlex) for 48 hours. In experiment 2, the same ejaculates extended in experiment 1 were cushion-centrifuged, the supernatant was discarded, and the pellets were resuspended at 100 million sperm/mL with their respective extender. Semen was then cooled and stored as in experiment 1. In both experiments, sperm motility parameters, plasma membrane integrity, and high mitochondrial membrane potential were assessed at 0, 24, and 48 hours post cooling. For experiment 3, 12 mares (n = 24 cycles) were bred with 48 hour–cooled semen from one stallion. Semen was processed as described in experiment 1. Mares had embryo flushing performed by 8-day post-ovulation. In experiment 1, BotuSemen Gold displayed superior total and progressive motility relative to INRA 96 (P < .05). There were no significant differences between the types of containers in any experiment. In experiment 2, INRA 96 and BotuSemen Gold extenders had similar total and progressive motility, but BotuSemen Gold had superior sperm velocity parameters at all timepoints. Embryo recovery was identical for both extenders (50%). Finally, the results obtained herein suggest that BotuSemen Gold is a suitable alternative to be included in semen cooling tests against INRA 96 in clinical practice.  相似文献   
49.
50.
王利娟  常枨 《猪业科学》2020,37(6):102-104
在世界上主要的猪肉生产国中,猪人工授精(AI)技术的应用率在90%以上。尽管猪冷冻精液技术在不断进步,但由于其效率不高,在猪场实际生产中并不多见使用。在猪人工授精技术中,液态精液是目前应用最广泛的精液,与传统的牛冷冻精液不同,其独特的精子微胶囊保护膜技术,可以对猪精子进行更加完善的液态保存,因此液态精液是目前猪人工授精使用的主要方式。文章综述了猪精液保存技术在人工授精中的应用,并展望了今后的发展方向,为人工授精技术助力恢复生猪生产提供参考。  相似文献   
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