Some characteristics of the formations of acrosomal vesicles during the late stage of spermatids during spermiogenesis and taxonomical charateristics of sperm morphology in male two species (Saxidomus purpurata and Meretrix petechialis) in the family Veneridae were investigated by electron microscope observations. In two species, the morphologies of the spermatozoa have the primitive type and are similar to those of other bivalves in that it contains a short midpiece with five mitochondria surrounding the centrioles. The morphologies of the sperm nuclear types of S. purpurata and M. petechialis in Veneridae have the curved cylindrical and cylinderical type, respectively. And the acrosome shapes of two species are the same cap-shape type. In particular, the axial filament is not found in the lumen of the acrosome of two species, however, subacrosomal material are observed in the subacrosomal spaces between the anterior nuclear fossa and the acrosomal vesicle of two species. The spermatozoon of S. purpurata is approximately 46-$52{\mu}m$ in length, including a curved sperm nucleus (about $3.75{\mu}m$ in length), a long acrosome (about $0.40{\mu}m$ in length),and a tail flagellum (about 45-$47{\mu}m$ long). And the spermatozoon of M. petechialis is approximately 47-$50{\mu}m$ in length including a slightly curved sperm nucleus (about $1.50{\mu}m$ in length), an acrosome (about $0.56{\mu}m$ in length) and tail flagellum (44-$48{\mu}m$ in length). In two species, the axoneme of the sperm tail flagellum of each species consists of nine pairs of microtubules at the periphery and a pair of cental doublets at the center. Therefore, the axoneme of the sperm tail flagellum shows a 9 + 2 structure. In particular, taxonomically important some charateristics of sperm morphologies of two species in the family Veneridae are acrosomal morphology of the sperm, The axial filament is not found in the acrosome as seen in a few species of the family Veneridae in the subclass Heterodonta. The acrosomal vesicle is composed of right, left basal rings and the apex part of the acrosomal vesicle. In particular, right and left basal rings show electron opaque part (region), while the apex part of the acrosomal vesicle shows electron lucent part (region). These charateristics belong to the subclass Heterodonta, unlikely a characteristic of the subclass Pteriomorphia showing all part of the acrosome being composed of electron opaque part (region). Therefore, it is easy to distinguish the families or the subclasses by the acrosomal structures. The number of mitochondria in the midpiece of the sperm of S. purpurata and M. petechialis in Veneridae are five. However, the number of mitochondria in the midpiece of the sperm in most species of Veneridae in the subclass Heterodonta are four. Therefore, the number of mitochondria of the sperm midpiece of two species are exceptionally 5, and it is only exceptional case in the species in Veneridae in the subclass Heterodonta. Except these cases, the number of mitochondria in the sperm midpiece in all families in the subclass Heterodontaare are 4, and now widely used in taxonomic analyses.
BPA, a diphenyl compound containing groups, that make it structurally similar to synthetic estrogen and is considered as one of the major endocrine disruptors. Silymarin has extensively been used to prevent and/or alleviate some human disease, especially for the treatment of adverse liver conditions. It has an antioxidative efficacy and cancer preventive efficacy. Therefore, we examined the hypothesis that silymarin can inhibit BPA-induced toxicity in boar sperm duing in vitro storage. Sperm characteristics (motility, viability, membrane integrity and mitochondrion activity) in semen exposed to BPA (10~200 uM) were sharply lowered, while it increase in a dose and time dependent manner due to silymarin addition (50~200 uM) into semen extender in the presence of BPA (100 uM). All of the evaluated characteristics were gradually improved in the groups that were treated with silymarin (50~200 uM) in the presence of BPA (100 uM) in comparison to BPA 100 uM alone group, irrespective of incubation periods (3 and 6 h). These results demonstrate that silymarin can ameliorate the toxicity of BPA on boar sperm characteristics during in vitro storage, suggesting that silymarin indirectly act as an antioxidant.
The purpose of this study was to investigate the effect of taurine on sperm characteristics and gene expressions(bax and Gpx) in fresh boar semen during in vitro storage. The motility of spermatozoa in Modena, Modana plus taurine 25 mM, Modana plus taurine 50 mM, Modana plus taurine 75 mM and Modana plus taurine 100 mM were 63.1%, 65.1%, 65.3%, 82.5% and 80.8%, respectively. (omitted)
This study was carried out to compare the semen characteristics, frozen-thawed sperm viability and testosterone concentration and in vitro fertilization (IVF) and development of in vitro matured pig oocytes between two Yorkshire boars. Semen and blood samples were collected once per week from October to November 2002 from two adult Yorkshire boars at 18 months of age with 170 kg body weight. Sperm were deep frozen in 5 ml maxi-straws with lactose-egg yolk and N-acetyl-D-glucosamine (LEN) diluent and stored in liquid nitrogen. Blood samples were obtained at 10 a.m. by inserting a 21 gauge, hypodermic needle attached to 10 ml syringe into surface veins in the ear. The concentration of testosterone was determined by Competitive Enzyme Immunoassay. Ovaries were collected from prepubertal gilts at a local slaughter house. Cumulus oocyte complexes were aspirated from antral follicles (3 to 6 mm in diameter). The medium used for oocyte maturation was modified TCM 199. After about 22 h of culture, oocytes were cultured without cysteamine and hormones for 22 h at $38.5^{\circ}C$, 5% $CO_2$ in air. For IVF, one frozen 5 ml straw was thawed at $52^{\circ}C$in 40 sec and was diluted with 20 ml Beltsville thawing solution at room temperature. Sperm were washed 2 times in mTLP-PVA and inseminated without preincubation after thawing. Oocytes were inseminated with $2{\times}10^7$/ml sperm concentration. Oocytes were coincubated for 6 h in 500 ${\mu}$l mTBM fertilization medium. At 6 h after IVF, oocytes were transferred into 500 ${\mu}$l NCSU-23 culture medium for further culture of 48 and 144 h. There were no significant differences in the semen volume, motility, normal acrosome morphology and sperm concentration of raw semen between A and B of Yorkshire boar. However, motility and normal acrosome of boar A were higher than those of boar B at 0.5, 2, 3, 4, 5 and 6 h incubations of frozen-thawed sperm. Testosterone concentration (3.75 ng/ml) of boar A was higher than that (2.34 ng/ml) of boar B. The rate of blastocyst formation (15.1%) of boar A was higher than that (10.4%) of boar B. In conclusion, serum testosterone concentration of boar showed very important role for the frozen-thawed sperm viability and the blastocyst formation of pig oocytes matured in vitro.
Objective: To determine whether characteristics of sperm motility obtained by computer-assisted sperm analysis (CASA) could predict pregnancy after intrauterine insemination (IUI) in couples with unexplained infertility. Methods: Three hundred eighty-three cycles of intrauterine insemination with superovulation were retrospectively analyzed. Semen analysis was performed with CASA before and after swim-up and the parameters were compared between pregnant and non-pregnant women. Results: The pregnancy rate per cycle was 14.1%. Pregnant and non-pregnant women were comparable in terms of age, infertility duration, the number of dominant follicles. While sperm concentration, motility, and parameters such as average path velocity (VAP) and percentage rapid (RAPID) before semen preparation were significantly different between the pregnancy and non-pregnancy groups, there were no differences in sperm parameters when comparing the two groups after preparation. Using a receiver operating characteristic curve to measure sensitivity and specificity, the optimal threshold value for the predictors of pregnancy was revealed to be a concentration of ${\geq}111{\times}10^6/mL$, a motility of ${\geq}$ 51.4%, and RAPID ${\geq}$ 30.1% before preparation for IUI. Conclusion: Sperm parameters including concentration, motility, and RAPID before sperm preparation could have predictive value for pregnancy outcome after intrauterine insemination with superovulation in couples with unexplained infertility, and would be helpful when counseling patients before they make the decision to proceed with IVF/ICSI-ET.
This study was carried out to investigate the general characteristics such as volume, sperm concentration, sperm motility, sperm abnormality on whole semen, RSP-S and RSP-T semen and fractional semen of small size dogs, and the effect of temperature and preservation time and cryoproservation on motility of whole and RSP-S and RSP- T semen. Multiple ejaculates were collected from small dogs by the digital manipulation of penis. 1. The volume per ejaculate semen, sperm of concentration and motility and abnormal sperm rate of 1st fractional semen were 0.65±0.09㎖, 4.52±0.35×10/sup 6/ cells/㎖, 15.64±3.85% and 5.50±0.62%. Also, 2nd fractional semen were 1.25±0.20㎖, 3.35±0.48×10/sup 6/cells/㎖, 96.25±4.65% and 4.24±0.46%. And 3rd fractional semen were 1.45±0.21㎖, 3.85±0.52×10/sup 6/cell/㎖, 92.82±4.24% and 4.66±0.58%, respectively. 2. The sperm of concentration and motility and abnormal sperm rates of whole, RSP-S and RSP-T semen were 5.45±0.82×10/sup 6/ cells/㎖, 95.55±4.65%, 4.58±0.45% and 4.82±0.36×10/sup 6/cells/㎖, 90.10±3.42%, 6.48±0.68% and 4.55±0.45× 10/sup 6/cells/㎖, 93.25±3.85%, 4.82±0.58%, respectively. 3. The motility of whole, RSP-S and RSP-T semen were higher at 4℃ than at 38℃. When preservation temperature was at 4℃, survival rates of RSP-S and RSP-T sperm were 97.54%-6.25% at 1-72 hrs, 97.40%-5.62% at 1-100 hrs, respectively. 4. The survival rates of slow and rapid frozen 2nd fraction, RSP-S and RSP-T semen were 67.3±4.45%, 88.8±4.46% and 46.4±3.84%, 74.4±4.20%, respectively. Survival rates was significantly higher in frozen RSP-S and RSP-T semen than that in control group(8.5±2.12%).
This study examined the characteristics of eel Anguilla japonica sperm using the CASA (computer-assisted sperm analysis) system and attempted to provide the composition for artificial seminal plasma by regulating of inorganic elements. Sperm samples were first divided into four groups based on motility and progressive motility: (A) 0-10%, (B) 10-40%, (C) 40-70%, and (D) 70-100%. For observing sperm velocity variations, VCL, which is curve motion velocity, showed the highest values in all groups. The directional factor, beat cross frequency, was lower in higher activity groups, showing an opposite correlation with sperm activity. The head sizes of spermatozoa in higher activity groups were significantly larger than those in lower activity groups. The Na+ and K+ ions were important in the inorganic composition of seminal plasma in this species. Furthermore, regulating the composition in artificial seminal plasma improved the formula compared to the existing element, exhibiting 120 mM Na and 30 mM K when the sperm was conserved for a long time and 120 mM NA and 40 mM K when the sperm was conserved for a short time.
Artificial insemination (AI) with frozen or cooled semen is widely used in commercial fields of cattle and pig. Little is known about characteristics of canine sperm after freezing or cooling. For both practical and commercial goal, the canine semen treated with cooling and freezing should be carried out to exam the fundamentals, including sperm motility, survivability and fertilizing capacity. The aim of this study, thus, was to identify the effects of extended exposure to 4$0^{\circ}C$ on canine semen by motility, survivability, acrosomal changes following different duration. Fifteen ejaculates collected by digital manipulation twice per week from 3 dogs (Shih-Tzu) were divided to 16 aliquots after adding Tris-egg yolk (TE) buffer formulated by our laboratory, and cooled from 37 to 4$^{\circ}C$, by ramp rate of 0.6$^{\circ}C$/min. Each sample was evaluated by their motility, survivability and the acrosomal status at 0h (control), 2h, 12h and 1 d~10 d, respectively. The motility of spermatozoa was graded to 6 levels using the modified method of Seager. The survivability of sperm was assessed using an epifluorescence microscope after Fert/Light (Mole-cular Probes Inc.) staining. To estimate the proportion of the spermatozoa of intact acrosome, 200 spermatozoa were assessed in randomly selected fields, using epifluorescence microscope after FITC/PSA (Sigma) staining. At 2 h after cooling, the motility of most spermatozoa were assessed to be grade 0 and 1. At 12 h, high number of sperm were in grade 0 to 1, however, it was significantly (P<0.05) lower than that of 2 h. From 1 d to 4 d, ~50% of sperm was assessed to grade 0 to 1. On day 7, a little sperm were in grade 0 to 1. No sperm showed motility on day 10. Sperm motility was rapidly reduced by the percent of 10% of grade 0 to 1. From 2 h to 6 h, the number of live sperm was 90% and the sperm chilled for 10 days lived>50%. Acrosomal intact of spermatozoa exposed to 4$^{\circ}C$ for 2 h was 51%, supposed the sperm of control was 100%. Our results suggest that 1) this is easy to transfer and preservation for short periods 2) AI can be used by semen chilled for 6-Day.
For evaluating the boar semen quality, sperm motility (MOT) is an important parameter because the movement of spermatozoa indicates active metabolism, membrane integrity and fertilizing capacity. Estrogen receptors 2(ESR2) is involved in estrogen related apoptosis in cell cycle spermatogenesis, but their functions have not been confirmed in pig until now. Therefore, this study was conducted to analyze their association with sperm motility and kinematic characteristics. DNA samples from 105 Duroc pigs with records of semen motility and kinematic characteristics [Total motile spermatozoa (MOT), Curvilinear velocity(VCL), Straight-line velocity(VSL), the ratio between VSL and VCL(LIN), Amplitude of Lateral Head displacement(ALH)] were analyzed. A SNP in coding region of ESR2 g.35547A > G in exon 5 was associated with MOT (p < 0.05) in Duroc population. Therefore, we suggest that the porcine ESR2 gene may be used as a molecular marker for Duroc boar semen quality, although its functional effects were not defined yet. These results might shed new light on the roles of ESR2 in spermatogenesis as candidate gene for boar fertility, but still the lack of association across populations should be considered.
Pasqualotto, Fabio F.;Sharma, Rakesh K.;Nelson, David R.;Thomas, Jr, Anthony J.;Agarwal, Ashok
대한생식의학회:학술대회논문집
/
2000.06a
/
pp.37-42
/
2000
Objective: To determine whether particular semen characteristics in various clinical diagnoses of infertility are associated with high oxidative stress and whether any group of infertile men is more likely to have high seminal oxidative stress. Reactive oxygen species (ROS) play an important role in sperm physiological functions, but elevated levels of ROS or oxidative stress are related to male infertility. Design: Measurement of sperm concentration, motility, morphology, seminal ROS, and total antioxidant capacity (TAC) in patients seeking infertility treatment and controls. Setting: Male infertility clinic of a tertiary care center. Patient(s): One hundred sixty-seven infertile patients and 19 controls. Intervention(s): None. Main Outcome Measure(s): Semen characteristics, seminal ROS, and TAC in samples from patients with various clinical diagnoses and controls. Result(s): Fifteen patients (9.0%) were Endtz positive and 152(91.0%) Endtz negative. Sperm concentration, motility, and morphology were significantly reduced in all groups compared with the controls (P = .02), except in varicocele associated With infection group. Mean (${\pm}$SD) ROS levels in patient groups ranged from 2.2 ${\pm}$ 0.13 to 3.2 ${\pm}$ 0.35, signilicantly higher than controls (1.3 ${\pm}$ 0.3; P<.005). Patient groups had a significantly lower mean (${\pm}$SD) TAC from 1014.75 ${\pm}$ 79.22 to 1173.05 ${\pm}$ 58.07 than controls (1653 ${\pm}$ 115.28, P<.001), except ill the vaseclony reversal group (1532.02 ${\pm}$ 74.24). Sperm concentration was negatively correlated with ROS both overall and within all groups (P${\leq}$.007), with the exception of idiopathic infertility. Conclusion(s): Irrespective of the clinical diagnosis and semen characteristics, the presence of seminal oxidative stress in infertile men suggests its role in the pathophysiology of infertility. Medical or surgical treatments for infertility in these men should include strategies to reduce oxidative stress.
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