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21.
22.
Semen alterations in porcine rubulavirus-infected boars are related to viral excretion and have implications for artificial insemination 总被引:1,自引:1,他引:0
Solís M Ramírez-Mendoza H Mercado C Espinosa S Vallejo V Reyes-Leyva J Hernández J 《Research in veterinary science》2007,83(3):403-409
Porcine rubulavirus (PoRV), also known as blue eye disease (BED) of swine, causes respiratory and reproductive problems in pigs at several developmental stages. To study the effect of PoRV infection on semen production, five boars were infected with 1 x 10(6) TCID(50)/ml of PoRV strain PAC-3 and evaluated for 59 days post inoculation (DPI). Infected boars developed reproductive tract pathology that included swelling of the testes and epididymides. Analysis of the semen showed that the infection had little effect on semen production in four animals, but semen from one boar showed severe alterations in sperm concentration, motility, and morphology. When motility was analyzed in BTS-diluted semen after 24, 48, or 72 h, alterations were detected in all boars. Furthermore, viral antigen was detected in semen, the seminal plasma fraction, or sperm fraction from all boars. These results showed that PoRV is excreted via semen and, therefore, artificial insemination is a potential route of dissemination. 相似文献
23.
LI Zhi-ming ZHENG Shui-ping LI Chun-ming ZHANG He-ping Aquatic Technical Extension Centre Inner Mongolia Huhhot China Xilinguole Region Animal Husbandry Centre Inner Mongolia Xilinhot China 《华北农学报》2006,(Z3)
为提高鱼类的精子保存及授精孵化水平,对转基因镜鲤的精子在0.5%水解乳蛋白Hanks液中进行了常温(23℃)和冷藏(4℃)保存试验,并观察其活力及保持时间。结果表明,冷藏保存的精子不论其活力、活力持续时间及保存时间均好于常温保存的效果。对保存2d的精子进行了授精及孵化试验。结果表明,经保存的精子(2d)完全可以授精和孵化出苗。 相似文献
24.
Tetsuji OKAZAKI Shuji YOSHIDA Hisanori TESHIMA Masayuki SHIMADA 《Animal Science Journal》2011,82(3):412-419
In our previous study, seminal plasma effectively suppressed the induction of sperm to capacitation‐like status and acrosome loss during the thawing process. However, because boar seminal plasma is contaminated with various kinds of bacteria and/or viruses, it is necessary to develop a thawing solution without animal‐derived materials. In this study, we focused on the increase of intracellular Ca2+ ([Ca2+]i) in sperm after thawing and the negative effects of sperm qualities. After thawing, the fluorescent intensity of [Ca2+]i indicator, Fluo‐3/AM, and the level of phosphorylated tyrosine residue of protein were increased in the sperm. Next, we investigated whether the addition of Ca2+ chelators (ethylenediaminetetraacetic acid (EDTA) and ethyleneglycoltetraacetic acid (EGTA)) improved post‐thawed sperm motility. When the frozen–thawed sperm were treated with 6 mmol/L EDTA + 6 mmol/L EGTA, sperm motility was significantly increased as compared with control (6 mmol/L EDTA alone) at all incubation periods (P < 0.05). The combinational treatment significantly suppressed the elevation of [Ca2+]i and the tyrosine phosphorylation, which improved the acrosomal status and fertilizing ability in vitro. Furthermore, when the thawing method was applied for artificial insemination, the fertilization rate was significantly higher than control (P < 0.05, 33% vs. 82%). Thus, we conclude that the addition of EDTA + EGTA to thawing solution is a beneficial tool for artificial insemination using frozen–thawed boar sperm. 相似文献
25.
Deep-frozen semen from 28 bulls belonging to 6 different A.I. centres was studied after thawing and the ATP content in the spermatozoa was assayed using a bioluminescence technique. The sperm motility was subjectively estimated under a phase contrast microscope and the sperm concentration of each ejaculate was calculated in a haemocytometer. The overall mean ATP content was 16.6 nmoles ATP/spermatozoa x 10(8). There was a significant variation in ATP content between A.I. centres. Significant differences between bulls in ATP content were found as well as a significant correlation between ATP concentration and the number of motile spermatozoa. This may indicate that ATP assessment may be useful as an additional, objective laboratory test. 相似文献
26.
对11只狸獭(Myocastorcoypus)用按摩和电刺激相结合的方法人工采精32只次,成功27次,成功率84.4%;射精量为(0.97±0.16)mL,精子密度(7.34±1.49)亿/mL,精子活力0.65±0.12,精子畸形率(8.81±2.51)%,精液pH值6.44±0.16。对诱排公狸施行输精管结扎术,先后给5只母狸人工输精,每只输精2~3次,在输精后40~60d检查,4只受孕,其中有3只顺利产仔,产仔数分别为7只、7只、4只 相似文献
27.
Sven Viring 《Acta veterinaria Scandinavica》1980,21(4):587
Twenty-four gilts were inseminated pair-wise with live or dead spermatozoa from the same ejaculate. The insemination dose was 100 ml undiluted semen containing, on average, 19×109 spermatozoa. The gilts were slaughtered 1, 2, 6 and 12 h after insemination. The numbers of spermatozoa were counted in the uterus, uterotubal junction and in four equally long segments of the oviduct, called I–IV, with a haemocytometer. IV was adjacent to the uterotubal junction. The numbers of spermatozoa recovered in the uterus diminished significantly during the first 12 h after insemination. From gilts inseminated with live spermatozoa more spermatozoa were recovered in the uterotubal junction than from gilts inseminated with dead spermatozoa. Two h after insemination spermatozoa were recovered in all oviducts. Significantly more live than dead spermatozoa were recovered in Segments III and IV of the oviduct, regardless of time. In gilts inseminated with live spermatozoa the sperm count in Segment I varied significantly with time, being hiigest 2 h after insemination. At 6 and 12 h there were no distinct differences in the distribution of live spermatozoa between the various oviduct segments. The numbers of spermatozoa recovered in the oviduct were at these times apparently related to the sperm depots in the uterotubal junction. 相似文献
28.
随着我国人民生活水平的提高,膳食结构必将发生改变,动物性食品包括牛奶及其加工品的生产与消费也将与日俱增。当前我国奶牛业主要表现在产奶量方面,但面临着供不应求与价格问题,甚至出现宰奶牛供肉用的危机。但国外则呈现不同的发展情况。因事关人民营养和农牧业配合的经济开发,对这些问题近年笔者曾著文有所论及。今再根据最近几年国内外的资料与实况了解,侧重于国外乳业生产与供销等问题作一论述。 相似文献
29.
Johanna Lindahl Anne-Marie Dalin Gesa Stuhtmann Jane M Morrell 《Acta veterinaria Scandinavica》2012,54(1):40
Background
One of the challenges faced by equine breeders is ensuring delivery of good quality semen doses for artificial insemination when the mare is due to ovulate. Single Layer Centrifugation (SLC) has been shown to select morphologically normal spermatozoa with intact chromatin and good progressive motility from the rest of the ejaculate, and to prolong the life of these selected spermatozoa in vitro. The objective of the present study was a proof of concept, to determine whether fertilizing ability was retained in SLC-selected spermatozoa during prolonged storage.Findings
Sixteen mares were inseminated with SLC-selected sperm doses that had been cooled and stored at 6°C for 48 h, 72 h or 96 h. Embryos were identified in 11 mares by ultrasound examination 16–18 days after presumed ovulation.Conclusion
SLC-selected stallion spermatozoa stored for up to 96 h are capable of fertilization. 相似文献30.
Sorting stallion semen into two separate populations of enriched X- or Y-bearing sperm can be done successfully. For this, stallion semen can be shipped to a sorting facility, but the mare must be in close to the sorting laboratory. Fertility rates when using 20-40 million sperm are an acceptable 60% per insemination. The procedure can be implemented in embryo transfer programs, with no deleterious effect on the pregnancy rate or embryonic death. 相似文献