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1.
梅花鹿精子冷冻前后形态和超微结构的研究 总被引:9,自引:0,他引:9
采用光学显微镜和电子显微镜对冷冻前后的梅花鹿精子的形态和超显微结构进行了观察。结果表明:梅花鹿精子全长61.6±2.70μm,其中头长7.19±0.47μm,中段长12.08±0.75μm。线粒体的螺旋数是63.68±4.66旋,中段线粒体每个螺旋约由3~5个线粒体组成。梅花鹿精子超微结构有3个特点:一是头部的厚度为牛、羊、猪精子的1/2;二是在中环处的质膜未见反折现象,并且主段与中段的联接是以套管式镶嵌;三是末段以9+2结构变成20根(12+7+1)单丝管形式排列。冷冻处理可使梅花鹿精子顶体膨胀,顶体内容物丢失,顶体内发生空泡,顶体外膜自身囊泡化,线粒体发生断裂和丢失,末段纤维束因质膜丢失而分散成扫帚状。冷冻后的梅花鹿精子畸形率极显著增高(P<0.01),冷冻解冻是致使梅花鹿精子顶体完整率和活力降低的主要原因。 相似文献
2.
Hamster sperm hyperactivation is enhanced by progesterone, and this progesterone-enhanced hyperactivation is suppressed by 17β-estradiol (17βE2) and γ-aminobutyric acid (GABA). Although it has been indicated that melatonin also enhances hyperactivation, it is unknown whether melatonin-enhanced hyperactivation is also suppressed by 17βE2 and GABA. In the present study, melatonin-enhanced hyperactivation was significantly suppressed by 17βE2 but not by GABA. Moreover, suppression of melatonin-enhanced hyperactivation by 17βE2 occurred through non-genomic regulation via the estrogen receptor (ER). These results suggest that enhancement of hyperactivation is regulated by melatonin and 17βE2 through non-genomic regulation. 相似文献
3.
Ayumi HASEGAWA Keiji MOCHIDA Toshiko TOMISHIMA Kimiko INOUE Atsuo OGURA 《The Journal of reproduction and development》2014,60(3):187-193
Successful in vitro fertilization (IVF) in mice has been achieved using spermatozoa at concentrations
specifically optimized for the experimental conditions, such as species and source of spermatozoa. Although IVF in mice is
mostly performed using about 80–500 µl drops, it is expected that the number of spermatozoa used for insemination can be
reduced by decreasing the size of the IVF drops. The present study was undertaken to examine the extent to which the number
of spermatozoa used for IVF could be reduced by using small droplets (1 µl). We devised the experimental parameters using
frozen–thawed spermatozoa from C57BL/6 mice in anticipation of broader applications to other mouse facilities. We found that
as few as 5 spermatozoa per droplet could fertilize oocytes (1 or 3 oocytes per droplet), although the fertilization rates
were low (13–15%). Practical fertilization rates (> 40%) could be achieved with frozen-thawed C57BL/6J spermatozoa, which
are sensitive to cryopreservation, when 20 sperm per droplet were used to inseminate 3 oocytes. Even with spermatozoa from a
very poor quality suspension (10% motility), about 25% of oocytes were fertilized. Our calculations indicate that the number
of inseminated spermatozoa per oocyte can be reduced to 1/96–1/240 by this method. In two separate embryo transfer
experiments, 60% and 47%, respectively, of embryos developed to term. Our microdroplet IVF method may be particularly
advantageous when only a limited number of motile spermatozoa are available because of inadequate freezing-thawing or genetic
reasons. 相似文献
4.
Carmen RODENAS Inmaculada PARRILLA Jordi ROCA Emilio Arsenio MARTINEZ Xiomara LUCAS 《The Journal of reproduction and development》2014,60(5):355-361
The aim of this study was to evaluate the effects of rapid cooling prior to freezing on frozen-thawed canine sperm quality.
In experiment 1, centrifuged ejaculates from 6 dogs were pooled, split into 4 aliquots and cryopreserved by the Uppsala
procedure using different cooling rates (control, cooling speed 18 C/90 min and average cooling rate 0.2 C/min; rapid,
cooling speed 18 C/8 min and average cooling rate 2.25 C/min) in combination with 2 glycerol addition protocols (fractionated
or unfractionated). In experiment 2, centrifuged ejaculates from 4 dogs were processed individually using the same cooling
rates described in experiment 1 in combination with an unfractionated glycerol addition protocol. Each of the experiments was
replicated 5 times. Sperm quality was evaluated after 30 and 150 min of post-thawing incubation at 38 C. Total motility (TM),
progressive motility (PM) and quality of movement parameters were assessed using a computerized system, and sperm viability
(spermatozoa with intact plasma and acrosome membranes) was assessed using flow cytometry (H-42/PI/FITC-PNA). Values for TM,
PM, viable spermatozoa and the quality of movement parameters after thawing were not significantly affected by the cooling
rate. The interaction between the cooling rate and the added glycerol protocol was not significant. There were significant
differences among the males (P<0.01) in the sperm quality parameters evaluated after thawing. The interaction between the
males and the cooling rate was not significant. In conclusion, canine spermatozoa can be cryopreserved using the Uppsala
method at an average cooling rate of 2.25 C/min prior to freezing together with addition of fractionated or unfractionated
glycerol. 相似文献
5.
This study tested KUROKURA solution (Kurokura et al., 1984, Aquaculture 37, 267–274) and its modifications (by increasing NaCl content to 160, 180 and 200 mM) on immobilizing properties for sampling and short-term preservation of potential motility of tench spermatozoa. The immobilizing solution is used because, when collected, the sperm of most samples is contaminated by urine, causing spermatozoa to be of poor quality, with low motilities and velocities (almost 0), thus resulting in a worsened fertilization and hatching rate. Sperm was sampled with a syringe containing an immobilizing solution (IS), allowing an IS:sperm ratio of 2:1, under aerobic conditions at 0–4°C. This sperm solution was stored for 10 h and untreated sperm was collected prior to fertilization as a control. Spermatozoa quality was evaluated for the cell motility and velocity parameters and also for fertilization ability and hatching rate. Results obtained for tench sperm motility, velocity, fertilization and hatching rate showed that only sperm collected in the various immobilizing solutions can be successfully used for artificial insemination and preservation after 10 h at 0–4°C. The best immobilizing solution was found to be KUROKURA 180 (180 mM NaCl, 2.68 mM KCl, 1.36 mM CaCl2· 2H2O and 2.38 mM NaHCO3), giving a fertility and hatching rate of 41%, with no change in rates after 10 h storage of sperm. Control sperm without immobilizing solution showed a fertilization and hatching rate of only 6–7%. 相似文献
6.
P. Routray A.K. Choudhary D.K. Verma P. Swain S.D. Gupta 《Aquaculture (Amsterdam, Netherlands)》2006,261(4):1204-1211
Cryopreservation of semen collected from dead fishes showed that it is possible to use it for fish production. We humanely killed individuals of the Indian major carp rohu, Labeo rohita and stored at different temperature regimes of 31 °C, 0 °C, − 10 °C and − 30 °C till 8 h. At every one hour interval semen from these fishes were collected by Pasteur pipette and evaluated for sperm yield/kg body weight, motility, pH, spermatocrit (%) and sperm count. The semen having suitable characteristics such as; 70% spermatocrit or above and motility index of 4 or above was cryopreserved by following a specific protocol. The cryopreserved semen of the dead fishes was stored for 7 days and then thawed in a water bath at 37 °C for 50 s. It was found that up to 8 h, spermatozoa of rohu were viable when stored at 0 °C or − 10 °C. Sperm collected after 8 h of fish death and maintained at 0 °C was the best stored condition that showed 30% larval survival. The spermatozoa collected 8 h after fish death was mostly normal as observed under scanning electron microscope and the total length of rohu spermatozoa was 25-30 μm. The hatchlings produced with this cryopreserved semen grew normally and juvenile fishes of rohu could be produced. This study suggests that germ cells such as spermatozoa of dead fishes can be cryopreserved and utilized for restoration of a species. It has the potential use in cryo-conservation of endangered fishes, restoration of animals through fertilization and genetic manipulation studies. 相似文献
7.
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9.
Although several selection techniques are available for processing spermatozoa, only colloid centrifugation has been used to any extent in this field, starting with density gradient centrifugation and progressing more recently to single-layer centrifugation (SLC). SLC through a species-specific colloid has been shown to be effective in selecting spermatozoa with good motility and normal morphology from stallion semen. The method is easier to use and less time-consuming than density gradient centrifugation, and has been scaled-up to allow whole ejaculates to be processed in a practical manner. The potential applications of SLC in equine breeding are as follows: to improve sperm quality in artificial insemination doses for “problem” ejaculates, to increase the shelf life of normal sperm doses, to remove pathogens (viruses, bacteria), to improve cryosurvival by removing dead and dying spermatozoa before freezing or after thawing, to select spermatozoa for intracytoplasmic sperm injection, and to aid conservation breeding. 相似文献
10.
Priscilla N. Guasti Gabriel A. MonteiroRosiara R. Maziero MSc Ian MartinBruno R. Avanzi MSc José A. Dellaqua Jr.Frederico O. Papa PhD 《Journal of Equine Veterinary Science》2013
This study evaluated whether pentoxifylline (PTX) present in the flushing extender influenced the function of equine epididymal spermatozoa after recovery and after thawing. For this experiment, 58 testicles from 29 Brazilian Jumping Horses were used. Cauda epididymides of each stallion were separated and flushed with a skim milk extender, with or without 7.18 mM PTX and then subjected to the freezing process. Samples flushed with the extender containing PTX showed a significant increase in total motility, progressive motility, straight line velocity, curvilinear velocity, and percentage of rapid sperm immediately after the recovery of epididymal sperm and after 15 minutes of incubation at 37°C (P < .05). However, the presence of PTX in the flushing extender did not affect the post-thaw motility parameters or plasma membrane integrity (P > .05). The results of this study showed that the PTX present in the flushing extender improved motility parameters of recently recovered epididymal sperm and had no deleterious effects on plasma membrane integrity and freezability of equine epididymal sperm. 相似文献