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81.
The energetic status of fresh sperm of wild Atlantic salmon (Salmo salar L.) was presented in selected males (n=10) with motility rate ≥80%. Purine and pyridine nucleotides: adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP), guanosine triphosphate, guanosine diphosphate, guanosine monophosphate, inosine monophosphate, nicotinamide adenine dinucleotide and nicotinamide adenine dinucleotide phosphate; nucleosides: adenosine, guanosine and inosine; bases: hypoxanthine, xanthine and uric acid were determined using the high‐performance liquid chromatography method. The average value of adenylate energy charge in the group was 0.77 ± 0.10, and the mean total adenine nucleotide content (TAN) was 65.1 ± 18.3 pmol × 10?6 spermatozoa. The mean concentrations of ATP, ADP and AMP were 43.5, 11.8 and 9.9 pmol × 10?6 spermatozoa respectively. The concentrations of the other energetic nucleotides studied were lower. In all males studied (n=23) with a motility rate from 0% to 95%, no statistically significant correlation between the per cent of motile sperm and ATP concentration was found (Rs=0.35), whereas the correlation between the per cent of motile sperm and ADP was statistically significant (Rs=0.60). A negative correlation was found between hypoxanthine and the per cent of motile spermatozoa (Rs=?0.44). Our results suggest that hypoxanthine is the final product of salmon spermatozoa of adenine nucleotide catabolism.  相似文献   
82.
分别注射1、3、5个顶体完整的人精子于金黄地鼠卵中,对照组同时注射数量相等的无顶体精子,观察卵活化、受精及后期发育情况.结果发现随着注入精子数量的增加,卵发育的异常率显著增加,而注射无顶体精子组,无论注射精子数量为多少,均无异常发生.此外,注射多个精子于金黄地鼠卵中时,多原核(PN)形成率顶体完整组明显低于无顶体组(P...  相似文献   
83.
Sperm cryopreservation has led to transcendental changes in the reproductive biotechnology of both mammals and fish, and is a basic tool for animal improvement. However, these protocols generate damage to cell structure and physiology, altering sperm function as a result of cryoinjuries during freezing and thawing. This review is a compilation of the techniques developed and standardised for assessing sperm function in cryopreserved fish semen. Recent studies have analysed sperm function objectively, applying cellular and molecular techniques to characterise cryodamage. The Computer Assisted Sperm Analysis system has facilitated the assessment of motility, while electron microscopy (SEM and TEM) and cryo‐microscopy have made it possible to study sperm morphology and ultra‐structure. The effects of cryodamage on nuclear DNA have also been analysed using various methods, including the comet Fluorescence in situ Hybridization test, TUNEL, Sperm Chromatin Structure Assay, specific DNA sequences using RT‐PCR and specific genes by qPCR. The latter technique is used to study the mitochondrial genome (mtDNA), together with some candidate genes which are associated with bioenergy activity and sperm motility. Other parameters assessed are mitochondrial membrane potential and ATP content using high performance liquid chromatography, nuclear magnetic resonance spectrometry and cell respiration. All this information makes it possible to establish study and assessment criteria for cryopreserved fish spermatozoa. This work focuses on the use of technologies to study of quality of fish spermatozoa during cryopreservation.  相似文献   
84.
Heavy metals are highly toxic elements that are present in the environment, especially in water. Mercury chloride (HgCl2) stands out among these compounds because of its strong ability to induce damage to any tissue with which it comes into contact. The gametes of spawning aquatic animals, such as fish, are susceptible to such damage. Thus, our objective was to evaluate the toxic potential of HgCl2 in the capacitation and activation of Rhamdia quelen sperm. Semen was collected from seven males and activated in 58 mM sodium chloride (NaCl) containing 0 (control), 4?10, 7?10, 7?9, and 7?8 M HgCl2. The evaluated variables included motility, vigor, motility time, morphology, membrane integrity, membrane fluidity, mitochondrial functionality, production of reactive oxygen species (ROS), and DNA fragmentation. All evaluated HgCl2 concentrations increased primary pathologies and reduced motility, vigor and motility time. Damage to membrane integrity and fluidity began occurring at a concentration of 7?10 M HgCl2. These results indicate that HgCl2 has a toxic effect on different sites of fish spermatozoa and that sperm motility decreases after exposure to HgCl2, impairing sperm capacitation and activation.  相似文献   
85.
1. Aim of this study was the development of an optimised cryopreservation pellet procedure for chicken semen and the assessment of DNA and membrane integrity in frozen/thawed spermatozoa in a Hubbard F15 meat type selected strain.

2. The following semen processing conditions were studied: spermatozoa working concentration (SWC), 1.5 vs 2 × 109 cells/ml in pre-freezing extender; equilibration of diluted semen at 5°C, 20 vs 40 min; dimethylacetamide concentration, 6% vs 9%; dimethylacetamide equilibration time at 5°C, 1 vs 30 min; thawing at 60°C for 10 vs 50°C for 30 sec. Spermatozoa viability (EtBr exclusion procedure – stress test), mobility (Accudenz® swim-down test) and subjective motility were assessed in fresh and frozen-thawed semen.

3. The lower SWC (1.5 × 109 cells/ml) and the higher dimethylacetamide concentration (9%) had positive significant effects on the recovery rate of motile (22% vs 16%) and viable spermatozoa (39 vs 34%), respectively.

4.Membrane (SYBR14-PI staining) and DNA integrity (comet assay) were assessed before and after freezing/thawing according to the optimised protocol.

5. Recovery rates of spermatozoa with undamaged plasma membrane and DNA were 41% and 76%, respectively. The distribution of spermatozoa in classes of DNA damage was also analysed and discussed.

6. It was concluded that pellet cryopreservation was a damaging process mainly for plasma membrane rather than nuclear DNA in chicken spermatozoa.  相似文献   

86.
分别在稀释、离心猪精液中添加0.2、0.4、0.8、1.6 mmol/L丁羟基甲苯(Butylated hydroxytoluene,BHT),15℃保存,检验保存35、d后精子TMS、PMI和NAR(%)、测定MDA浓度;确定并选择最佳BHT浓度用于猪精液冷冻保存,检验解冻后TMS、PMI、NAR和Mt-MP(%)、测定MDA浓度。结果显示:BHT显著提高稀释精液、离心精液各项指标百分率(P0.05),且MDA浓度显著降低(P0.05),BHT最佳浓度分别为0.8、1.6 mmol/L;0.8 mmol/L BHT显著提高冷冻-解冻精液各项指标百分率(P0.05),且MDA浓度显著降低(P0.05)。结果表明,BHT能通过抑制精子质膜氧化损伤,提高猪精液保存效果。  相似文献   
87.
In this study, cryopreservation feasibility of Persian sturgeon (Acipenser persicus) and the effect of different doses of 2‐hydroxypropyl‐beta‐cyclodextrin on thawed spermatozoa quality (motility duration and motility percentage) were investigated. For freezing, semen of seven male individuals was pooled in equal volumes and diluted with 4°C [Tris‐HCl (100 mM), pH = 8, DMSO 10%] extenders containing 0, 5, 10, 15 mM of HβCD in a ratio of 1:1(semen/extenders). Then semen was filled into 0.5‐mL straws, and was frozen with vapour of liquid nitrogen at 4‐cm above surface of liquid nitrogen. After 3 min, straws were plunged in to liquid nitrogen. Thawing was performed at 40°C water baths for 15 s. Motility duration of the 10 mM HβCD treated spermatozoa at days 14 (228.98 ± 16.39) and 56 (199.66 ±21.78) were longer than other treatments. In day 56, the motility percentage in treatment with 10 mM was significantly higher (16.14 ± 2.54) (P < 0.05) compared with 5 mM treatment (8.75 ± 2.47) (P < 0.05). Therefore, it is recommended that 10 mM of HβCD can be used as an additive cryoprotectant for increasing cryopreserved spermatozoa quality in this species.  相似文献   
88.
The aims of this study were to evaluate the efficiency of simple and complex extenders in prolonging the cold storage of sperm (Experiments 1 and 2) and to test the diluted‐cooled sperm in the best extender with regard to sperm quality parameters (Experiment 3) in the streaked prochilod, Prochilodus lineatus. In all the experiments, aliquots of 0.3 mL of sperm were diluted 1:10 in extenders and stored at 4–6 °C. Sperm diluted in simple extenders (NaCl and glucose solutions) yielded 0–26% sperm motility, whereas sperm diluted in complex extenders (BTS?, M III? and Androstar?) yielded 62–81% sperm motility on day 4 after cold storage. When Androstar? was further investigated, the following was observed on day 4: 53% motility with 94 s of duration; 47% live spermatozoa; 26–61% fertility rate; and 22–60% hatching rate. The use of Androstar? improves the sperm fertility of the streaked prochilod during a 4‐day storage period and can therefore be used to facilitate artificial reproduction.  相似文献   
89.
The objective of this study was to investigate the effects of extenders and storage time on motility, viability and fertilization of preserved black sharkminnow, Labeo chrysophekadion spermatozoa. Sperm were diluted 1:3 in one of five extenders: modified Cortland solution (MC); Hanks' balanced salt solution (HBSS); 0.9% sodium chloride (NaCl); Kurokura solution (KU); and modified extender, and undiluted sperm samples were used as control and stored at 4°C for 5 days. Motility, viability and fertilization rates were evaluated every day. After a storage time of three days, the highest motility, viability and fertilization rates (61.27 ± 2.26%, 58.60 ± 2.29% and 40.58 ± 0.57, respectively) were achieved with sperm diluted with modified extender. Motility, viability and fertilization rates decreased significantly (P < 0.05) with increasing storage time in all treatments. In addition, this study found that motility, viability and fertilization had a positive significant correlation (P < 0.01). The results indicate that isotonic extender is suitable for the short‐term preservation of black sharkminnow spermatozoa.  相似文献   
90.
旨在探究4℃液态保存中奶山羊精子超微结构变化,为阐明影响奶山羊精子液态保存质量的相关机制提供形态学依据.采集关中奶山羊精液进行4℃液态保存,伊红染色检测保存至0、24、48、72、96、120和144 h的精子活率,扫描电镜和透射电镜观察0、48、96 h的精子超微结构.伊红染色检测结果发现,精子活率随液态保存时间延长...  相似文献   
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