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Sample records for increased sperm production

  1. Enhanced early-life nutrition of Holstein bulls increases sperm production potential without decreasing postpubertal semen quality.

    PubMed

    Dance, Alysha; Thundathil, Jacob; Blondin, Patrick; Kastelic, John

    2016-08-01

    Enhanced early-life nutrition (∼130% of required energy and protein) increased testes size and weight (∼20-25%) and reduced age at puberty (∼1 month) in beef and dairy bulls, compared with those fed 70% of dietary requirements. The objective was to determine effects of early-life (2-31 weeks) nutritional modulation on feed costs, predicted number of harvestable sperm and doses of semen, and semen quality. Calves (∼1 week old) were randomly allocated into three groups that were fed 4, 6, or 8 L/day of milk (low [n = 8], medium [n = 9], and high groups [n = 9], respectively) from ages 2 to 8 weeks. Thereafter, they were weaned, transitioned onto barley silage-based diets, to receive ∼70, 100, or 130% of recommended amounts of energy and protein (feed costs were ∼CDN$280 more per bull to feed high versus low diets from 2 to 31 weeks). After 31 weeks, all bulls were fed a medium diet. Semen was collected, by electroejaculation, from 51 to 73 weeks, extended, chilled, and cryopreserved. Bulls fed high nutrition were numerically younger (P = 0.45) at sexual maturity (sperm with ≥30% progressive motility, ≥70% morphologically normal, and ≤20% abnormal heads), first acceptable post-chill sperm motility (>50%; P = 0.66) and first acceptable post-thaw motility (>25% progressive; P = 0.25) than bulls in the low-nutrition group. Semen from three bulls per group was used for in vitro fertilization (total of 1249 bovine oocytes); there were no significant differences among groups in fertilization percentage (mean ± SEM of 68.0 ± 8.7, 77.1 ± 3.5, and 68.7 ± 4.5% for low, medium, and high, respectively) or blastocyst yield (31.5 ± 5.6, 41.4 ± 4.9, and 33.7 ± 4.6%). On the basis of analysis of 2D gels of sperm proteins, 380 spots were identified on the fused master gel, but no spots were differentially expressed across groups. Overall, there were no significant differences in semen quality or sperm function among bulls fed

  2. Saccharin consumption increases sperm DNA fragmentation and apoptosis in mice

    PubMed Central

    Rahimipour, Marzieh; Talebi, Ali Reza; Anvari, Morteza; Abbasi Sarcheshmeh, Abolghasem; Omidi, Marjan

    2014-01-01

    Background: Saccharin is an artificial non-caloric sweetener that used to sweeten products such as drinks, candies, medicines, and toothpaste, but our bodies cannot metabolize it. Sodium saccharin is considered as an important factor in tumor promotion in male rats but not in humans. Objective: The objective of this study was to investigate the effect of saccharin consumption on sperm parameters and apoptosis in adult mice. Materials and Methods: Totally 14 adult male mice were divided into 2 groups. Group 1 served as control fed on basal diet and group 2 or experimental animals received distilled water containing saccharin (0.2% w/v) for 35 days. After that, the left cauda epididymis of each mouse was cut and placed in Ham’s F10. Swimmed-out spermatozoa were used to analyze count, motility, morphology (Pap-staining) and viability (eosin-Y staining). Sperm DNA integrity, as an indicator of apoptosis, was assessed by SCD (sperm chromatin dispersion) and terminal deoxynucleotidyl transferase (TUNEL) assay. Results: Following saccharin consumption, we had a reduction in sperm motility with respect to control animals (p=0.000). In addition, the sperm count diminished (17.70±1.11 in controls vs. 12.80±2.79 in case group, p=0.003) and the rate of sperm normal morphology decreased from 77.00±6.40 in control animals into 63.85±6.81 in saccharin-treated mice (p=0.001). Also, we saw a statistically significant increase in rates of sperm DNA damage and apoptosis in experimental group when compared to control one (p=0.001, p=0.002 respectively). Conclusion: Saccharin consumption may have negative effects on sperm parameters, and increases the rate of sperm DNA fragmentation and apoptosis in mice. PMID:25031574

  3. A cost for high levels of sperm competition in rodents: increased sperm DNA fragmentation.

    PubMed

    delBarco-Trillo, Javier; García-Álvarez, Olga; Soler, Ana Josefa; Tourmente, Maximiliano; Garde, José Julián; Roldan, Eduardo R S

    2016-03-16

    Sperm competition, a prevalent evolutionary process in which the spermatozoa of two or more males compete for the fertilization of the same ovum, leads to morphological and physiological adaptations, including increases in energetic metabolism that may serve to propel sperm faster but that may have negative effects on DNA integrity. Sperm DNA damage is associated with reduced rates of fertilization, embryo and fetal loss, offspring mortality, and mutations leading to genetic disease. We tested whether high levels of sperm competition affect sperm DNA integrity. We evaluated sperm DNA integrity in 18 species of rodents that differ in their levels of sperm competition using the sperm chromatin structure assay. DNA integrity was assessed upon sperm collection, in response to incubation under capacitating or non-capacitating conditions, and after exposure to physical and chemical stressors. Sperm DNA was very resistant to physical and chemical stressors, whereas incubation in non-capacitating and capacitating conditions resulted in only a small increase in sperm DNA damage. Importantly, levels of sperm competition were positively associated with sperm DNA fragmentation across rodent species. This is the first evidence showing that high levels of sperm competition lead to an important cost in the form of increased sperm DNA damage. PMID:26936246

  4. Inhibition of Mitochondrial Complex I Leads to Decreased Motility and Membrane Integrity Related to Increased Hydrogen Peroxide and Reduced ATP Production, while the Inhibition of Glycolysis Has Less Impact on Sperm Motility

    PubMed Central

    Plaza Davila, María; Martin Muñoz, Patricia; Tapia, Jose A.; Ortega Ferrusola, Cristina; Balao da Silva C, Carolina; Peña, Fernando J.

    2015-01-01

    Mitochondria have been proposed as the major source of reactive oxygen species in somatic cells and human spermatozoa. However, no data regarding the role of mitochondrial ROS production in stallion spermatozoa are available. To shed light on the role of the mitochondrial electron transport chain in the origin of oxidative stress in stallion spermatozoa, specific inhibitors of complex I (rotenone) and III (antimycin-A) were used. Ejaculates from seven Andalusian stallions were collected and incubated in BWW media at 37°C in the presence of rotenone, antimycin-A or control vehicle. Incubation in the presence of these inhibitors reduced sperm motility and velocity (CASA analysis) (p<0.01), but the effect was more evident in the presence of rotenone (a complex I inhibitor). These inhibitors also decreased ATP content. The inhibition of complexes I and III decreased the production of reactive oxygen species (p<0.01) as assessed by flow cytometry after staining with CellRox deep red. This observation suggests that the CellRox probe mainly identifies superoxide and that superoxide production may reflect intense mitochondrial activity rather than oxidative stress. The inhibition of complex I resulted in increased hydrogen peroxide production (p<0.01). The inhibition of glycolysis resulted in reduced sperm velocities (p<0.01) without an effect on the percentage of total motile sperm. Weak and moderate (but statistically significant) positive correlations were observed between sperm motility, velocity and membrane integrity and the production of reactive oxygen species. These results indicate that stallion sperm rely heavily on oxidative phosphorylation (OXPHOS) for the production of ATP for motility but also require glycolysis to maintain high velocities. These data also indicate that increased hydrogen peroxide originating in the mitochondria is a mechanism involved in stallion sperm senescence. PMID:26407142

  5. Sound production in neonate sperm whales (L)

    NASA Astrophysics Data System (ADS)

    Madsen, P. T.; Carder, D. A.; Au, W. W. L.; Nachtigall, P. E.; Møhl, B.; Ridgway, S. H.

    2003-06-01

    Acoustic data from two sperm whale neonates (Physeter macrocephalus) in rehabilitation are presented and implications for sound production and function are discussed. The clicks of neonate sperm whale are very different from usual clicks of adult specimens in that neonate clicks are of low directionality [SL anomaly (0°-90°) <8 dB], long duration (2-12 ms), and low frequency (centroid frequency between 300 and 1700 Hz) with estimated SLs between 140 and 162 dB//1 μPa (rms). Such neonate clicks are unsuited for biosonar, but can potentially convey homing information between calves and submerged conspecifics in open ocean waters at ranges of some 2 km. Moreover, it is demonstrated that sperm whale clicks are produced at the anterior placed monkey lips, thereby substantiating a key point in the modified Norris and Harvey theory and supporting the unifying theory of sound production in odontocetes.

  6. Sperm cells as vectors in the production of transgenic animals

    SciTech Connect

    Prince, R.M.

    1993-04-28

    Transgenic animals are used in industry and in biomedical research in order to provide in vivo experimental model systems. Sperm cells have been reported used as vectors in the production of transgenic animals before, however no approach has of yet proven to be successful. Fertilizing eggs with genetically modified sperm would be advantageous in that sperm are readily accessible and stable, and eggs can be fertilized by modified sperm cells in vivo. Recent elucidations regarding the unique manner of DNA packaging in sperm chromatin by protamines has provided us with the insight for developing a method of introducing foreign DNA into sperm which is likely to succeed where others have failed. We have developed a method for mimicking the in vivo system of sperm chromatin toroid subunits in vitro, concentrating these toroids, and fluorescent visualization. Our present work concerns development of a method to successfully deliver DNA across the cell membranes and into the nucleus.

  7. Sperm Pretreatment with Dithiothreitol Increases Male Pronucleus Formation Rates After Intracytoplasmic Sperm Injection (ICSI) in Swamp Buffalo Oocytes

    PubMed Central

    CHANKITISAKUL, Vibuntita; AM-IN, Nutthee; THARASANIT, Theerawat; SOMFAI, Tamas; NAGAI, Takashi; TECHAKUMPHU, Mongkol

    2012-01-01

    Abstract Failure of male pronucleus formation has hampered the success of intracytoplasmic sperm injection (ICSI) in swamp buffalo. The aim of the present study was to improve male pronucleus formation by pretreating sperm with various chemicals before ICSI. In Experiments1 and 2, sperm were treated according to one of the following protocols: (1) 0.1% Triton-X 100 (TX) for 1 min, (2) 10 µM calcium ionophore (CaI) for 20 min, (3) freezing and thawing (FT) without any cryoprotectant, or (4) no treatment (control). These sperm treatment groups then either did or did not receive additional sperm treatment with 5 mM dithiothreitol (DTT) for 20 min. Acrosomal integrity (Experiment 1) and DNA fragmentation (Experiment 2) were evaluated in the sperm before ICSI. In Experiment 3, oocytes matured in vitro were subjected to ICSI using pretreated sperm as described above and then were cultured either with or without activation. The TX- and CaI-treated sperm caused an increase in the number of acrosome-loss sperm, whereas the FT treatment and control increased the proportion of acrosome-reacted sperm (P<0.05). The DNA fragmentation did not differ among treatments (P>0.05). At 18 h post-ICSI, pronucleus (PN) formation was found only in activated oocytes. The majority of the activated ICSI oocytes contained intact sperm heads. Normal fertilization was observed in the CaI and FT treatment groups and control group when sperm were treated with DTT before ICSI. In conclusion, DTT treatment of sperm with reacted acrosomes before ICSI together with activation of the ICSI oocytes is important for successful male pronucleus formation. PMID:23132520

  8. Under-nutrition reduces spermatogenic efficiency and sperm velocity, and increases sperm DNA damage in sexually mature male sheep.

    PubMed

    Guan, Yongjuan; Malecki, Irek A; Hawken, Penelope A R; Linden, Matthew D; Martin, Graeme B

    2014-10-01

    We tested whether the quality of spermatozoa from mature male sheep would be affected during nutrition-induced changes in testicular mass. Merino rams were fed for 65 days with diets that increased, maintained or decreased body and testis mass (n=8 per group). In semen collected on Days 56 and 63, underfed rams had less sperms per ejaculate than well-fed rams (P<0.05) and a lower sperm velocity (computer-assisted semen analysis) than well-fed or maintenance-fed rams (P<0.05). Sperm chromatin structure assay revealed more sperm DNA damage in underfed rams than in well-fed rams (P<0.05). The amount of sperm DNA damage was inversely correlated with change in scrotal circumference (r=-0.6, P<0.05), the percentages of progressive motile sperm (r=-0.8; P<0.01) and motile sperm (r=-0.6, P<0.05), and the numbers of sperms per gram of testis (r=-0.55, P<0.05). In testicular tissue collected on Day 65, underfed rams had fewer sperm per gram of testis than rams in the other two groups (P<0.001). We conclude that, in adult rams, underfeeding reduces spermatogenic efficiency and that this response is associated with a reduction in spermatozoal quality. PMID:25086661

  9. Effect of refractoriness to long photoperiod on sperm production and quality in tomcats.

    PubMed

    Nuñez Favre, R; Bonaura, M C; Tittarelli, C M; Stornelli, M C; de la Sota, R L; Stornelli, M A

    2012-12-01

    The aim of this study was to assess whether refractoriness to long photoperiod (LP) could be reversed by subjecting tomcats to a period of short days. Our hypothesis was that photoperiod changes can avoid refractoriness and restore sperm quality and production to that before refractoriness. Tomcats (n = 6) were housed in a conditioned room with LP (12L: 12D) for 45 days of acclimation and then maintained under LP for 18 month. Then, tomcats were changed to a period of decreasing light at a rate of 8 min/day for 1 month. Tomcats stayed for 1 month with short photoperiod (SP; 8L: 16D) and then were switched back to a period of increasing light at a rate of 8 min/day for 1 month. The experiment was completed after tomcats remained in LP for 2 months. Toms were anaesthetized and semen samples were collected by electroejaculation every 2 weeks. Sperm parameters were evaluated in all ejaculates, and data were analysed by anova. Motility, velocity, volume, sperm concentration, total sperm count, viability, acrosome integrity, plasma membrane integrity and sperm morphology were higher during LP compared with a refractory LP (p < 0.01). Likewise, velocity, viability, acrosome integrity, plasma membrane integrity and sperm morphology were higher in a LP compared with a SP (p < 0.05). On the other hand, motility, volume, concentration and total sperm count were similar between LP and SP (p > 0.20).Whereas motility, velocity, viability, acrosome integrity and plasma membrane integrity were similar in a refractory LP compared with SP (p > 0.05), volume, sperm concentration, total sperm count and sperm morphology were lower in a refractory LP compared with SP (p < 0.05). In conclusion, refractoriness and reduced sperm production and quality induced by a prolonged LP of 18 month can be restored after placing tomcats to a SP. PMID:23279508

  10. Reactive oxygen species production and antioxidant enzyme activity during epididymal sperm maturation in Corynorhinus mexicanus bats.

    PubMed

    Arenas-Ríos, Edith; Rosado García, Adolfo; Cortés-Barberena, Edith; Königsberg, Mina; Arteaga-Silva, Marcela; Rodríguez-Tobón, Ahiezer; Fuentes-Mascorro, Gisela; León-Galván, Miguel Angel

    2016-03-01

    Prolonged sperm storage in the epididymis of Corynorhinus mexicanus bats after testicular regression has been associated with epididymal sperm maturation in the caudal region, although the precise factors linked with this phenomenon are unknown. The aim of this work is to determine the role of reactive oxygen species (ROS) and changes in antioxidant enzymatic activity occurring in the spermatozoa and epididymal fluid over time, in sperm maturation and storage in the caput, corpus and cauda of the bat epididymis. Our data showed that an increment in ROS production coincided with an increase in superoxide dismutase (SOD) activity in epididymal fluid and with a decrease in glutathione peroxidase (GPX) activity in the spermatozoa in at different time points and epididymal regions. The increase in ROS production was not associated with oxidative damage measured by lipid peroxidation. The results of the current study suggest the existence of a shift in the redox balance, which might be associated with sperm maturation and storage. PMID:26952757

  11. Seminal plasma arising from the whole boar sperm-rich fraction increases the stability of sperm membrane after thawing.

    PubMed

    Torres, M A; Ravagnani, G M; Leal, D F; Martins, S M M K; Muro, B B D; Meirelles, F V; Papa, F O; Dell'aqua, J A; Alvarenga, M A; Moretti, A S; De Andrade, A F C

    2016-05-01

    Boar spermatozoa arising from the sperm-rich ejaculate fraction are reported to have a more stable plasma membrane and are more resistant to cold shock and premature acrosome reaction than spermatozoa from the whole ejaculate. Furthermore, seminal plasma (SP) can increase the cryotolerance of boar spermatozoa, and in other domestic species, it has the ability to reverse cryopreservation damage. This study aimed to evaluate the effects of boar SP arising from the whole sperm-rich ejaculate fraction (SP-SRF) on the integrity, stability, and peroxidation of sperm membranes after thawing. Each ejaculate ( = 24) was divided among 4 treatments: control (CT), centrifuged and suspended in autologous SP-SRF (CS), centrifuged with withdrawn SP-SRF (CW), and post-thawed SP arising from the whole sperm-rich fraction addition to CW (CWSP). After thawing, all treatments were incubated for 5, 60, and 120 min and were analyzed for membrane integrity, fluidity, and peroxidation by flow cytometer. The absence of SP-SRF increased the lipid disorder ( < 0.05) but had no effect on lipid peroxidation ( > 0.05) or membrane integrity ( > 0.05). However, the increase in lipid disorder by withdrawal of SP-SRF was reversed by SP-SRF addition ( < 0.05) to the post-thawing medium, whereas plasma and acrosomal membrane integrity ( > 0.05) and lipid peroxidation ( > 0.05) were unchanged. In conclusion, despite the centrifugation effects, the addition of SP arising from the whole sperm-rich fraction to post-thawed boar semen decreased sperm lipid disorder without an influence of the sperm membrane integrity and peroxidation. PMID:27285688

  12. Bower-building behaviour is associated with increased sperm longevity in Tanganyikan cichlids.

    PubMed

    Morita, M; Awata, S; Yorifuji, M; Ota, K; Kohda, M; Ochi, H

    2014-12-01

    We investigated the evolutionary relationship between spawning behaviour and sperm motility traits among Tanganyikan mouth-brooding cichlid species that have developed diverse mating behaviours and male sexual traits. Mouth-brooding behaviour is common among these fish, but different species demonstrate a range of spawning behaviours, bower construction, male sexual traits and timing of gamete release. We observed spawning behaviours and compared sperm motility traits of 28 Tanganyikan mouth-brooding cichlids to elucidate the evolutionary correlations between these traits. Sperm longevity was considerably longer in bower-building species that construct crater-shaped spawning sites compared with species that do not build bowers. Male bower builders released sperm in the pit of the bower prior to spawning, and the time from ejaculation to fertilization was longer. Conversely, most mouth-brooding cichlids deposited semen directly into the female buccal cavity, and spawned eggs were immediately picked up to be placed inside the cavity; thus, the time from ejaculation to fertilization was short. These observations suggest that increased sperm longevity is favoured in bower builders. Comparative phylogenetic analyses suggested that bower-building behaviour and greater time from ejaculation to fertilization are associated with the extension of sperm longevity, whereas sperm competition rank does not play a major role. In addition, bower-building behaviour preceded the emergence of increased sperm longevity. These results indicate that the extension of sperm longevity as a result of the emergence of bower builders may have acted as an evolutionary attractor for sperm longevity. PMID:25330280

  13. Click production during breathing in a sperm whale (Physeter macrocephalus)

    NASA Astrophysics Data System (ADS)

    Wahlberg, Magnus; Frantzis, Alexandros; Alexiadou, Paraskevi; Madsen, Peter T.; Møhl, Bertel

    2005-12-01

    A sperm whale (Physeter macrocephalus) was observed at the surface with above- and underwater video and synchronized underwater sound recordings. During seven instances the whale ventilated its lungs while clicking. From this observation it is inferred that click production is achieved by pressurizing air in the right nasal passage, pneumatically disconnected from the lungs and the left nasal passage, and that air flows anterior through the phonic lips into the distal air sac. The capability of breathing and clicking at the same time is unique among studied odontocetes and relates to the extreme asymmetry of the sperm whale sound-producing forehead.

  14. First Production of Larvae Using Cryopreserved Sperm: Effects of Preservation Temperature and Cryopreservation on European Eel Sperm Fertilization Capacity.

    PubMed

    Asturiano, J F; Sørensen, S R; Pérez, L; Lauesen, P; Tomkiewicz, J

    2016-08-01

    Sperm cryopreservation is a useful tool in captive fish reproduction management, that is to synchronize gamete production, especially in the case of species as the European eel, where the time of female spawning readiness is unpredictable. Several protocols to cryopreserve sperm of this species have been described, but until recently fertilization trials were not feasible. This study evaluated the effect of cold storage of diluted sperm prior to fertilizations and tested whether a previously defined protocol for European eel sperm cryopreservation can be successfully applied in fertilization trials to produce viable offspring. In our experiment, the sperm motility was evaluated after the extraction and the best samples were selected and pooled. Until stripping of eggs and fertilization, diluted sperm samples were maintained at either 4 or 20°C, or cryopreserved, following existing protocols. Fertilization of two egg batches was attempted. Diluted sperm caused a similar percentage of fertilized eggs and a similar number of embryos and larvae, independently of storage temperature (4 or 20°C). The cryopreserved sperm resulted in a lower percentage of fertilized eggs, but embryos developed and a few larvae ('cryolarvae') were obtained 55 h after fertilization in one of the two egg batches. This result evidences that the tested cryopreservation protocol is applicable for eel reproduction management, although improvements will be required to enhance fertilization success. PMID:27189043

  15. Acetylcholinesterase-R increases germ cell apoptosis but enhances sperm motility

    PubMed Central

    Mor, I; Sklan, EH; Podoly, E; Pick, M; Kirschner, M; Yogev, L; Bar-Sheshet Itach, S; Schreiber, L; Geyer, B; Mor, T; Grisaru, D; Soreq, H

    2008-01-01

    Abstract Changes in protein subdomains through alternative splicing often modify protein-protein interactions, altering biological processes. A relevant example is that of the stress-induced up-regulation of the acetylcholinesterase (AChE-R) splice variant, a common response in various tissues. In germ cells of male transgenic TgR mice, AChE-R excess associates with reduced sperm differentiation and sperm counts. To explore the mechanism(s) by which AChE-R up-regulation affects spermatogenesis, we identified AChE-R's protein partners through a yeast two-hybrid screen. In meiotic spermatocytes from TgR mice, we detected AChE-R interaction with the scaffold protein RACK1 and elevated apoptosis. This correlated with reduced scavenging by RACK1 of the pro-apoptotic TAp73, an outcome compatible with the increased apoptosis. In contrast, at later stages in sperm development, AChE-R's interaction with the glycolytic enzyme enolase-α elevates enolase activity. In transfected cells, enforced AChE-R excess increased glucose uptake and adenosine tri-phosphate (ATP) levels. Correspondingly, TgR sperm cells display elevated ATP levels, mitochondrial hyperactivity and increased motility. In human donors' sperm, we found direct association of sperm motility with AChE-R expression. Interchanging interactions with RACK1 and enolase-α may hence enable AChE-R to affect both sperm differentiation and function by participating in independent cellular pathways. PMID:18194455

  16. Sperm cryopreservation in live-bearing Xiphophorus fishes: offspring production from Xiphophorus variatus and strategies for establishment of sperm repositories.

    PubMed

    Yang, Huiping; Cuevas-Uribe, Rafael; Savage, Markita G; Walter, Ronald B; Tiersch, Terrence R

    2012-09-01

    Cryopreservation of sperm from Xiphophorus fishes has produced live young in three species: X. hellerii, X. couchianus, and X. maculatus. In this study, the goal was to establish protocols for sperm cryopreservation and artificial insemination to produce live young in X. variatus, and to identify needs for repository development. The objectives were to: 1) collect basic biological characteristics of males; 2) cryopreserve sperm from X. variatus, 3) harvest live young from cryopreserved sperm, and 4) discuss the requirements for establishment of sperm repositories. The 35 males used in this study had a body weight of 0.298±0.096 g (mean±SD), body length of 2.5±0.2 cm, and testis weight of 6.4±3.4 mg. The sperm production per gram of testis was 2.33±1.32×10(9) cells. After freezing, the post-thaw motility decreased significantly to 37%±17% (ranging from 5% to 70%) (p=0.000) from 57%±14% (40%-80%) of fresh sperm (N=20). Artificial insemination of post-thaw sperm produced confirmed offspring from females of X. hellerii and X. variatus. This research, taken together with previous studies, provides a foundation for development of strategies for sperm repositories of Xiphophorus fishes. This includes: 1) the need for breeding strategies for regeneration of target populations, 2) identification of minimum fertilization capacity of frozen samples, 3) identification of fish numbers necessary for sampling and their genetic relationships, 4) selection of packaging containers for labeling and biosecurity, 5) assurance of quality control and standardization of procedures, 6) information systems that can manage the data associated with cryopreserved samples, including the genetic data, 7) biological data of sampled fish, 8) inventory data associated with frozen samples, and 9) data linking germplasm samples with other related materials such as body tissues or cells saved for DNA and RNA analyses. PMID:22924335

  17. Sperm Cryopreservation in Live-Bearing Xiphophorus Fishes: Offspring Production from Xiphophorus variatus and Strategies for Establishment of Sperm Repositories

    PubMed Central

    Cuevas-Uribe, Rafael; Savage, Markita G.; Walter, Ronald B.; Tiersch, Terrence R.

    2012-01-01

    Abstract Cryopreservation of sperm from Xiphophorus fishes has produced live young in three species: X. hellerii, X. couchianus, and X. maculatus. In this study, the goal was to establish protocols for sperm cryopreservation and artificial insemination to produce live young in X. variatus, and to identify needs for repository development. The objectives were to: 1) collect basic biological characteristics of males; 2) cryopreserve sperm from X. variatus, 3) harvest live young from cryopreserved sperm, and 4) discuss the requirements for establishment of sperm repositories. The 35 males used in this study had a body weight of 0.298±0.096 g (mean±SD), body length of 2.5±0.2 cm, and testis weight of 6.4±3.4 mg. The sperm production per gram of testis was 2.33±1.32×109 cells. After freezing, the post-thaw motility decreased significantly to 37%±17% (ranging from 5% to 70%) (p=0.000) from 57%±14% (40%–80%) of fresh sperm (N=20). Artificial insemination of post-thaw sperm produced confirmed offspring from females of X. hellerii and X. variatus. This research, taken together with previous studies, provides a foundation for development of strategies for sperm repositories of Xiphophorus fishes. This includes: 1) the need for breeding strategies for regeneration of target populations, 2) identification of minimum fertilization capacity of frozen samples, 3) identification of fish numbers necessary for sampling and their genetic relationships, 4) selection of packaging containers for labeling and biosecurity, 5) assurance of quality control and standardization of procedures, 6) information systems that can manage the data associated with cryopreserved samples, including the genetic data, 7) biological data of sampled fish, 8) inventory data associated with frozen samples, and 9) data linking germplasm samples with other related materials such as body tissues or cells saved for DNA and RNA analyses. PMID:22924335

  18. Cholesterol-Loaded Cyclodextrin Increases the Cholesterol Content of Goat Sperm to Improve Cold and Osmotic Resistance and Maintain Sperm Function after Cryopreservation.

    PubMed

    Salmon, Vianney M; Leclerc, Pierre; Bailey, Janice L

    2016-04-01

    The success of semen cryopreservation depends on sperm membrane integrity and function after thawing. Cholesterol-loaded cyclodextrin (CLC) is used for in vitro incorporation of cholesterol to protect cells against cold temperatures. We hypothesized that CLC treatment also enhances sperm cholesterol content to increase tolerance to osmotic shock and cryoresistance, thereby improving fertility. We confirmed the fact that treatment of goat semen with 3 mg/ml CLC increases sperm cholesterol content using both the Liebermann-Burchard approach and filipin III labeling of membrane cholesterol. Sperm were then treated with or without CLC and cryopreserved. After thawing, sperm cholesterol dramatically fell, even in the presence of CLC, which explains the mechanism of cryocapacitation. CLC treatment, however, maintained a normal prefreeze cholesterol level in sperm after cryopreservation. Furthermore, fresh sperm treated with CLC and subjected to either cold shock or incubated in hypo-, iso-, and hyperosmotic media, designed to mimic stresses associated with freezing/thawing, displayed increased temperature and osmotic tolerance. CLC treatment also improved sperm viability, motility, and acrosome integrity after thawing. Furthermore, CLC treatment did not affect the sperm's ability to undergo in vitro capacitation according to chlortetracycline fluorescence and protein tyrosine phosphorylation. A pilot field trial demonstrated that artificial insemination with sperm that underwent increased cholesterol levels following CLC treatment yielded higher fertility ( ITALIC! P< 0.1) and proliferation ( ITALIC! P< 0.05) rates in vivo than untreated semen from the same ejaculate samples. These observations suggest that CLC treatment could be used to improve cryoprotection during the freezing and thawing of goat sperm. PMID:26888968

  19. Management and sperm production of boars under differing environmental conditions.

    PubMed

    Kunavongkrit, Annop; Suriyasomboon, Annop; Lundeheim, Nils; Heard, Terry W; Einarsson, Stig

    2005-01-15

    The management of boars to ensure good sperm production under differing environmental conditions is a major concern for pig keepers in both tropical countries and countries where there are extreme environmental changes. Such changes create stress in animals and influence the production of spermatozoa. High temperatures during hot summer months may result in lower feed consumption and create stresses that result in the inhibition of spermatogenesis. Although tropical countries do not have a problem with major variations in day length, this can cause problems such as decreased litter size and infertility in other regions of the world. Evaporative cooling systems built into boar accommodation are often used to reduce fluctuations in both temperature and humidity during the hot and humid months seen in tropical countries. The system has become popular in AI boar studs, where it is reported to reduce stress and improve feed consumption. Other management factors, such as housing comfort, social contact, mating conditions and the frequency of mating, are also very important boar management aids that assist good quality semen production; these will be covered briefly in this review. This review will consider primarily those management factors, for example, the management of temperature and humidity using evaporative cooling systems and other techniques that enable AI boar studs to maximize sperm fertility through adjustments to the environment. PMID:15626423

  20. Organophosphorous pesticide exposure increases the frequency of sperm sex null aneuploidy.

    PubMed Central

    Recio, R; Robbins, W A; Borja-Aburto, V; Morán-Martínez, J; Froines, J R; Hernández, R M; Cebrián, M E

    2001-01-01

    It has been estimated that 4 of 1,000 live births and 35% of spontaneous abortions are aneuploid and that an important proportion of embryo and newborn aneuploidy is of paternal origin. Exposure to organophosphorous pesticides (OP) has been associated with sperm hyperploidy/polyploidy. Therefore, we aimed to assess the frequency of sperm aneuploidy (X, Y, and 18) and its relationship with urinary OP metabolites in agricultural workers. We performed multicolor fluorescence in situ hybridization on samples from nine men obtained before and during the pesticide spraying season to assess sperm aneuploidy. We measured urinary OP metabolite levels by gas-liquid chromatography. Aneuploidies were found in 0.67% of total sperm nuclei. The most frequent aneuploidy was the lack of a sexual chromosome or sex null (0.19%), followed by XY18 (0.15%) and XY18-18 (0.06%). OP metabolites detected at higher concentrations were dimethylthiophosphate, dimethyldithiophosphate, and diethylphosphate (DEP). There were no differences in average aneuploidy frequency or urinary metabolite levels between samples collected before and after exposure. However, Poisson regression analysis adjusted for age, alcohol intake, and sperm concentration showed significant associations between OP metabolite concentrations and increased frequency of sperm aneuploidies. The association was more evident between DEP and sex null, and the risk increased further during the spraying season. Thus, OP exposure could interfere with sperm chromosome segregation and increase the risk for genetic syndromes, such as Turner's. Further studies are required to assess the prevalence of spontaneous abortions, birth defects, and genetic syndromes in agricultural communities. PMID:11748030

  1. Increasing storage time of extended boar semen reduces sperm DNA integrity.

    PubMed

    Boe-Hansen, Gry B; Ersbøll, Annette K; Greve, Torben; Christensen, Preben

    2005-04-15

    There is an extensive use of artificial insemination (AI) in the pig industry. Extended liquid boar semen may be used for insemination for up to 5 days after collection. The objective of this study was to determine the changes in sperm quality, when boar semen was extended and stored at 18 degrees C for up to 72 h post-collection. The study included three ejaculates from five boars, for each of the four breeds: Duroc, Hampshire, Landrace and Danish Large White (n=60 ejaculates). The sperm chromatin structure assay (SCSA) showed an increase in DNA fragmentation index (DFI) after 72 h of incubation (P<0.001), with no differences between breeds (P=0.07). For two Hampshire boars, all ejaculates had a large increase in DFI after 24 h of incubation. The standard deviation of DFI (SD-DFI) differed between breeds, with the SD-DFI for Hampshire being significantly greater than for the other breeds. The SD-DFI did not change during the 72 h of storage. Sperm viability was determined using SYBR-14 and propidium iodide in combination with flow cytometry. The sperm viability did not differ between breeds (P=0.21), but a difference in viability during storage (P<0.001) was detected. In conclusion, the SCSA cytogram patterns were consistent for different ejaculates within boars and storage of extended boar semen at 18 degrees C for 72 h significantly decreased the integrity of sperm DNA. PMID:15823356

  2. A Specific Transitory Increase in Intracellular Calcium Induced by Progesterone Promotes Acrosomal Exocytosis in Mouse Sperm.

    PubMed

    Romarowski, Ana; Sánchez-Cárdenas, Claudia; Ramírez-Gómez, Héctor V; Puga Molina, Lis del C; Treviño, Claudia L; Hernández-Cruz, Arturo; Darszon, Alberto; Buffone, Mariano G

    2016-03-01

    During capacitation, sperm acquire the ability to undergo the acrosome reaction (AR), an essential step in fertilization. Progesterone produced by cumulus cells has been associated with various physiological processes in sperm, including stimulation of AR. An increase in intracellular Ca(2+) ([Ca(2+)]i) is necessary for AR to occur. In this study, we investigated the spatiotemporal correlation between the changes in [Ca(2+)]i and AR in single mouse spermatozoa in response to progesterone. We found that progesterone stimulates an [Ca(2+)]i increase in five different patterns: gradual increase, oscillatory, late transitory, immediate transitory, and sustained. We also observed that the [Ca(2+)]i increase promoted by progesterone starts at either the flagellum or the head. We validated the use of FM4-64 as an indicator for the occurrence of the AR by simultaneously detecting its fluorescence increase and the loss of EGFP in transgenic EGFPAcr sperm. For the first time, we have simultaneously visualized the rise in [Ca(2+)]i and the process of exocytosis in response to progesterone and found that only a specific transitory increase in [Ca(2+)]i originating in the sperm head promotes the initiation of AR. PMID:26819478

  3. Disruption of Maternal DNA Repair Increases Sperm-DerivedChromosomal Aberrations

    SciTech Connect

    Marchetti, Francesco; Essers, Jeroun; Kanaar, Roland; Wyrobek,Andrew J.

    2007-02-07

    The final weeks of male germ cell differentiation occur in aDNA repair-deficient environment and normal development depends on theability of the egg to repair DNA damage in the fertilizing sperm. Geneticdisruption of maternal DNA double-strand break repair pathways in micesignificantly increased the frequency of zygotes with chromosomalstructural aberrations after paternal exposure to ionizing radiation.These findings demonstrate that radiation-induced DNA sperm lesions arerepaired after fertilization by maternal factors and suggest that geneticvariation in maternal DNA repair can modulate the risk of early pregnancylosses and of children with chromosomal aberrations of paternalorigin.

  4. Male mating behaviour and sperm production characteristics under varying sperm competition risk in guppies.

    PubMed

    Evans; Magurran

    1999-11-01

    Since natural populations of guppies, Poecilia reticulata, often differ from one another in social structure, the intensity of sperm competition is likely to vary between localities. Guppies are promiscuous, with female choice for colourful males playing a central role in the mating system. In addition, male guppies use forced copulations to circumvent female choice. Both methods of copulation are used interchangeably by individual males, but the degree to which either is used may depend on the social environment into which males are born. Here we show that male mating behaviour varies according to the rearing sex ratio: when reared in male-biased groups, males performed more forced copulations and fewer courtship displays but showed the opposite pattern of behaviour when reared in female-biased groups. Our prediction, based on sperm competition theory, that stripped sperm number would reflect social structure was not supported by our results. Instead, the overall level of sexual activity (gonopodial thrusts+sigmoid displays) was a better predictor of sperm number in the different groups of males. Rearing density, where sex ratio was controlled, did not significantly affect male mating behaviour or sperm traits. Males reared under the different sex ratios continued to show their characteristic behaviour patterns when placed in equal sex ratio tanks. We conclude, therefore, that males adopt mating strategies to suit their social environment, and that these strategies remain fixed, for short periods at least, if population structure changes. Copyright 1999 The Association for the Study of Animal Behaviour. PMID:10564602

  5. Sperm competition and the evolution of precopulatory weapons: Increasing male density promotes sperm competition and reduces selection on arm strength in a chorusing frog.

    PubMed

    Buzatto, Bruno A; Roberts, J Dale; Simmons, Leigh W

    2015-10-01

    Sperm competition theory assumes a trade-off between precopulatory traits that increase mating success and postcopulatory traits that increase fertilization success. Predictions for how sperm competition might affect male expenditure on these traits depend on the number of competing males, the advantage gained from expenditure on weapons, and the level of sperm competition. However, empirical tests of sperm competition theory rarely examine precopulatory male expenditure. We investigated how variation in male density affects precopulatory sexual selection on male weaponry and the level of sperm competition in the chorusing frog Crinia georgiana, where males use their arms as weapons in male-male combat. We measured body size and arm girth of 439 males, and recorded their mating success in the field. We found density-dependent selection acting on arm girth. Arm girth was positively associated with mating success, but only at low population densities. Increased male density was associated with higher risk and intensity of sperm competition arising from multimale amplexus, and a reversal in the direction of selection on arm girth. Opposing patterns of pre- and postcopulatory selection may account for the negative covariation between arm girth and testes across populations of this species. PMID:26375605

  6. Increasing productivity: Another approach

    SciTech Connect

    Norton, F.J.

    1996-06-10

    An engineering information (EI) and information technology (IT) organization that must improve its productivity should work to further its business goals. This paper explores a comprehensive model for increasing EI/IT productivity by supporting organizational objectives.

  7. Testes Mass, but Not Sperm Length, Increases with Higher Levels of Polyandry in an Ancient Sex Model

    PubMed Central

    Vrech, David E.; Olivero, Paola A.; Mattoni, Camilo I.; Peretti, Alfredo V.

    2014-01-01

    There is strong evidence that polyandrous taxa have evolved relatively larger testes than monogamous relatives. Sperm size may either increase or decrease across species with the risk or intensity of sperm competition. Scorpions represent an ancient direct mode with spermatophore-mediated sperm transfer and are particularly well suited for studies in sperm competition. This work aims to analyze for the first time the variables affecting testes mass, ejaculate volume and sperm length, according with their levels of polyandry, in species belonging to the Neotropical family Bothriuridae. Variables influencing testes mass and sperm length were obtained by model selection analysis using corrected Akaike Information Criterion. Testes mass varied greatly among the seven species analyzed, ranging from 1.6±1.1 mg in Timogenes dorbignyi to 16.3±4.5 mg in Brachistosternus pentheri with an average of 8.4±5.0 mg in all the species. The relationship between testes mass and body mass was not significant. Body allocation in testes mass, taken as Gonadosomatic Index, was high in Bothriurus cordubensis and Brachistosternus ferrugineus and low in Timogenes species. The best-fitting model for testes mass considered only polyandry as predictor with a positive influence. Model selection showed that body mass influenced sperm length negatively but after correcting for body mass, none of the variables analyzed explained sperm length. Both body mass and testes mass influenced spermatophore volume positively. There was a strong phylogenetic effect on the model containing testes mass. As predicted by the sperm competition theory and according to what happens in other arthropods, testes mass increased in species with higher levels of sperm competition, and influenced positively spermatophore volume, but data was not conclusive for sperm length. PMID:24736525

  8. Testes mass, but not sperm length, increases with higher levels of polyandry in an ancient sex model.

    PubMed

    Vrech, David E; Olivero, Paola A; Mattoni, Camilo I; Peretti, Alfredo V

    2014-01-01

    There is strong evidence that polyandrous taxa have evolved relatively larger testes than monogamous relatives. Sperm size may either increase or decrease across species with the risk or intensity of sperm competition. Scorpions represent an ancient direct mode with spermatophore-mediated sperm transfer and are particularly well suited for studies in sperm competition. This work aims to analyze for the first time the variables affecting testes mass, ejaculate volume and sperm length, according with their levels of polyandry, in species belonging to the Neotropical family Bothriuridae. Variables influencing testes mass and sperm length were obtained by model selection analysis using corrected Akaike Information Criterion. Testes mass varied greatly among the seven species analyzed, ranging from 1.6 ± 1.1 mg in Timogenes dorbignyi to 16.3 ± 4.5 mg in Brachistosternus pentheri with an average of 8.4 ± 5.0 mg in all the species. The relationship between testes mass and body mass was not significant. Body allocation in testes mass, taken as Gonadosomatic Index, was high in Bothriurus cordubensis and Brachistosternus ferrugineus and low in Timogenes species. The best-fitting model for testes mass considered only polyandry as predictor with a positive influence. Model selection showed that body mass influenced sperm length negatively but after correcting for body mass, none of the variables analyzed explained sperm length. Both body mass and testes mass influenced spermatophore volume positively. There was a strong phylogenetic effect on the model containing testes mass. As predicted by the sperm competition theory and according to what happens in other arthropods, testes mass increased in species with higher levels of sperm competition, and influenced positively spermatophore volume, but data was not conclusive for sperm length. PMID:24736525

  9. Gamete evolution and sperm numbers: sperm competition versus sperm limitation.

    PubMed

    Parker, Geoff A; Lehtonen, Jussi

    2014-09-22

    Both gamete competition and gamete limitation can generate anisogamy from ancestral isogamy, and both sperm competition (SC) and sperm limitation (SL) can increase sperm numbers. Here, we compare the marginal benefits due to these two components at any given population level of sperm production using the risk and intensity models in sperm economics. We show quite generally for the intensity model (where N males compete for each set of eggs) that however severe the degree of SL, if there is at least one competitor for fertilization (N - 1 ≥ 1), the marginal gains through SC exceed those for SL, provided that the relationship between the probability of fertilization (F) and increasing sperm numbers (x) is a concave function. In the risk model, as fertility F increases from 0 to 1.0, the threshold SC risk (the probability q that two males compete for fertilization) for SC to be the dominant force drops from 1.0 to 0. The gamete competition and gamete limitation theories for the evolution of anisogamy rely on very similar considerations: our results imply that gamete limitation could dominate only if ancestral reproduction took place in highly isolated, small spawning groups. PMID:25100694

  10. Ameliorative effect of quercetin against arsenic-induced sperm DNA damage and daily sperm production in adult male rats.

    PubMed

    Jahan, Sarwat; Rehman, Saima; Ullah, Hizb; Munawar, Asma; Ain, Qurat Ul; Iqbal, Tariq

    2016-07-01

    In this study, the protective effect of quercetin was evaluated against arsenic induced reproductive ailments in male rats. For this purpose, male rats (n = 5/group) weighing 180-250 g were used. First group served as control, second group received arsenic (50 ppm) in drinking water. Third group was treated with quercetin (50 mg/kg) alone, while fourth group received arsenic + quercetin. All treatments were carried out for 49 days. After treatment, animals were killed by decapitation; testis and epididymis were dissected out. Right epididymis was minced immediately for comet assay, while left epididymis was processed for histology. Similarly, right testis was homogenized for estimation of daily sperm production (DSP) and detection of metal concentration. The results of our research revealed that arsenic treatment did not cause any significant change in body weight and testicular volume. Quercetin treatment significantly prevented tissue deposition of arsenic within the testis. Arsenic treatment caused a significant reduction in DSP, however, in the arsenic + quercetin-treated group and quercetin alone-treated group, DSP was significantly high as compared to the arsenic-treated group. Histological study of epididymis showed empty lumen in arsenic-treated group while in arsenic + quercetin-treated group and quercetin alone-treated group, lumen were filled with sperm and were comparable to control. Sperm DNA damage, induced by arsenic, was significantly reversed toward control levels by supplementation of quercetin. These results suggest that quercetin not only prevents deposition of arsenic in tissues, but can also protect the sperm DNA damage. PMID:26524343

  11. The tyrosine kinase FER is responsible for the capacitation-associated increase in tyrosine phosphorylation in murine sperm.

    PubMed

    Alvau, Antonio; Battistone, Maria Agustina; Gervasi, Maria Gracia; Navarrete, Felipe A; Xu, Xinran; Sánchez-Cárdenas, Claudia; De la Vega-Beltran, Jose Luis; Da Ros, Vanina G; Greer, Peter A; Darszon, Alberto; Krapf, Diego; Salicioni, Ana Maria; Cuasnicu, Patricia S; Visconti, Pablo E

    2016-07-01

    Sperm capacitation is required for fertilization. At the molecular level, this process is associated with fast activation of protein kinase A. Downstream of this event, capacitating conditions lead to an increase in tyrosine phosphorylation. The identity of the tyrosine kinase(s) mediating this process has not been conclusively demonstrated. Recent experiments using stallion and human sperm have suggested a role for PYK2 based on the use of small molecule inhibitors directed against this kinase. However, crucially, loss-of-function experiments have not been reported. Here, we used both pharmacological inhibitors and genetically modified mice models to investigate the identity of the tyrosine kinase(s) mediating the increase in tyrosine phosphorylation in mouse sperm. Similar to stallion and human, PF431396 blocks the capacitation-associated increase in tyrosine phosphorylation. Yet, sperm from Pyk2(-/-) mice displayed a normal increase in tyrosine phosphorylation, implying that PYK2 is not responsible for this phosphorylation process. Here, we show that PF431396 can also inhibit FER, a tyrosine kinase known to be present in sperm. Sperm from mice targeted with a kinase-inactivating mutation in Fer failed to undergo capacitation-associated increases in tyrosine phosphorylation. Although these mice are fertile, their sperm displayed a reduced ability to fertilize metaphase II-arrested eggs in vitro. PMID:27226326

  12. Increased N6-methyladenosine in Human Sperm RNA as a Risk Factor for Asthenozoospermia

    PubMed Central

    Yang, Ying; Huang, Wei; Huang, Jing-Tao; Shen, Fan; Xiong, Jun; Yuan, Er-Feng; Qin, Shan-shan; Zhang, Ming; Feng, Yu-Qi; Yuan, Bi-Feng; Liu, Song-Mei

    2016-01-01

    Male infertility is a worldwide medical problem. Asthenozoospermia is a common cause of infertility. Epigenetic modifications of DNA and histones have been shown to influence human infertility, but no research has explored whether N6-methyladenosine (m6A) level in RNA is associated with asthenozoospermia. Here, we collected a total of 52 semen samples, including 20 asthenozoospermia patients and 32 healthy controls. An LC-ESI-MS/MS method was used to detect m6A contents in sperm RNA, and real-time PCR was performed to determine the mRNA expression of demethylase (FTO, ALKBH5), methyltransferase (METTL3, METTL14, WTAP) and an m6A-selective-binding protein (YTHDF2). We found that m6A content (p = 0.033) and the mRNA expression of METTL3 (p = 0.016) and METTL14 (p = 0.025) in asthenozoospermia patients were significantly higher than those of controls. Increased m6A content was a risk factor for asthenozoospermia (odds ratio (OR) 3.229, 95% confidence interval (CI) 1.178 – 8.853, p = 0.023). Moreover, m6A content was correlated with the expression of METTL3 (r = 0.303, p = 0.032) and with sperm motility (progressive motility: r = −0.288, p = 0.038; non-progressive motility: r = −0.293, p = 0.037; immotility: r = 0.387, p = 0.005). Our data suggest that increased m6A content is a risk factor for asthenozoospermia and affects sperm motility. Methyltransferases, particularly METTL3, play key roles in increasing m6A contents in sperm RNA. PMID:27072590

  13. Increasing Public Library Productivity.

    ERIC Educational Resources Information Center

    Samuelson, Howard

    1981-01-01

    Suggests ways of improving productivity for public libraries faced with increased accountability, dwindling revenues, and continuing inflation. Techniques described include work simplification, work analysis, improved management, and employee motivation. (RAA)

  14. Bupropion treatment increases epididymal contractility and impairs sperm quality with no effects on the epididymal sperm transit time of male rats.

    PubMed

    Cavariani, Marilia Martins; de Almeida Kiguti, Luiz Ricardo; de Lima Rosa, Josiane; de Araújo Leite, Gabriel Adan; Silva, Patrícia Villela E; Pupo, André Sampaio; De Grava Kempinas, Wilma

    2015-09-01

    Bupropion is a dopamine (DA) and norepinephrine (NE) reuptake inhibitor used as smoking cessation and antidepressant drug with a lower incidence of male sexual dysfunction. We showed previously that sibutramine, a norepinephrine/serotonine reuptake inhibitor, reduced male rat fertility. As there are no studies evaluating the impact of bupropion treatment on spermatic parameters and male fertility, we evaluated the effects of bupropion treatment (15 and 30 mg kg(-1), 30 days) on sexual behavior, spermatic parameters and fertility of male Wistar rats and on the epididymal duct in vitro contractility. Bupropion 15 mg kg(-1) increased the serum luteinizing hormone level and the epididymal duct contractility, but the sperm quality was not affected. At 30 mg kg(-1) bupropion impaired sperm quality increasing the incidence of non-progressive sperm. The male sexual behavior and fertility were not modified at both bupropion doses. These results, in rats, suggest the importance of studies evaluating the effects of bupropion on the human male sperm quality. PMID:25645087

  15. Productivity increases in science

    SciTech Connect

    Danko, J.E.; Young, J.K.; Molton, P.M.; Dirks, J.A.

    1993-02-01

    The study quantifies the impact on the cost of experimentation of synergistic advancements in instrumentation, theory, and computation over the last two decades. The study finds that the productivity of experimental investigation (experimental results/$) is increasing as science is transformed from a linear, isolated approach to a hierarchical, multidisciplinary approach. Developments such as massively parallel processors coupled with instrumental systems with multiple probes and diverse data analysis capabilities will further this transformation and increase the productivity of scientific studies. The complexities and scale of today's scientific challenges are much greater than in the past, however, so that the costs of research are increasing. Even though science is much more productive in terms of the experimental results, the challenges facing scientific investigators are increasing at an even faster pace. New approaches to infrastructure investments must capitalize on the changing dynamics of research and allow the scientific community to maximize gains in productivity so that complex problems can be attacked cost-effectively. Research strategies that include user facilities and coordinated experimental, computational, and theoretical research are needed.

  16. Productivity increases in science

    SciTech Connect

    Danko, J.E.; Young, J.K.; Molton, P.M.; Dirks, J.A.

    1993-02-01

    The study quantifies the impact on the cost of experimentation of synergistic advancements in instrumentation, theory, and computation over the last two decades. The study finds that the productivity of experimental investigation (experimental results/$) is increasing as science is transformed from a linear, isolated approach to a hierarchical, multidisciplinary approach. Developments such as massively parallel processors coupled with instrumental systems with multiple probes and diverse data analysis capabilities will further this transformation and increase the productivity of scientific studies. The complexities and scale of today`s scientific challenges are much greater than in the past, however, so that the costs of research are increasing. Even though science is much more productive in terms of the experimental results, the challenges facing scientific investigators are increasing at an even faster pace. New approaches to infrastructure investments must capitalize on the changing dynamics of research and allow the scientific community to maximize gains in productivity so that complex problems can be attacked cost-effectively. Research strategies that include user facilities and coordinated experimental, computational, and theoretical research are needed.

  17. Effects of dietary energy on sexual maturation and sperm production in Holstein bulls.

    PubMed

    Harstine, B R; Maquivar, M; Helser, L A; Utt, M D; Premanandan, C; DeJarnette, J M; Day, M L

    2015-06-01

    In prepubertal bulls and heifers of dairy and beef breeds, puberty can be induced to occur earlier than typical with targeted high-energy diets due to precocious activation of the endocrine mechanisms that regulate puberty. Precocious activation of puberty in bulls intended for use in the AI industry has the potential to hasten and perhaps increase sperm production. It was hypothesized that feeding bulls a high-energy diet beginning at 8 wk of age would advance the prepubertal rise in LH and lead to advanced testicular maturation and age at puberty. From 58 to 230 ± 0.3 d of age, Holstein bulls received either a high-energy diet (HE;n = 9; targeted ADG 1.5 kg/d) or a control diet (CONT;n = 10; targeted ADG 0.75 kg/d). Thereafter, all bulls were fed a similar diet. The HE treatment increased LH secretion at 125 d of age, testosterone concentrations from 181 to 210 d, and scrotal circumference (SC) from 146 to 360 d of age relative to the CONT treatment. Beginning at 241 ± 5 d of age, semen collection (artificial vagina) was attempted every 14 d in bulls from the HE (n = 8) and CONT (n = 7) treatment until each bull attained puberty (ejaculate containing 50 × 10 spermatozoa with 10% motility). To assess semen production as mature bulls, semen was collected thrice weekly beginning at 541 ± 5 d of age until slaughter at 569 ± 5 d of age. After slaughter, epididymal and testicular measurements were collected and testicular tissue was fixed to determine seminiferous tubule diameter. Age at puberty did not differ between treatments (310 ± 35 d). Although testis and epididymal weight and testis volume were greater (P < 0.05) in the HE than the CONT treatment, sperm production of mature bulls did not differ between treatments. Diameter of seminiferous tubules also did not differ between treatments. We conclude that the HE advanced aspects of sexual maturation and increased testes size, but this was not reflected in hastened puberty or sperm production in the present

  18. ZP-binding peptides identified via phage display stimulate production of sperm antibodies in dogs.

    PubMed

    Samoylova, Tatiana I; Cox, Nancy R; Cochran, Anna M; Samoylov, Alexandre M; Griffin, Brenda; Baker, Henry J

    2010-07-01

    Zona pellucida (ZP) glycoproteins play a central role in sperm-oocyte binding and fertilization. Sperm protein sequences that are involved in sperm-ZP recognition and have an important role in fertilization represent attractive targets for development of contraceptive vaccines, yet are currently unknown. To identify peptide sequences that recognize and bind to ZP proteins, we developed a novel selection procedure from phage display libraries that utilizes intact oocytes surrounded by ZP proteins. The major advantage of this procedure is that ZP proteins remain in their native conformation unlike a selection protocol previously published that utilized solubilized ZP on artificial solid support. Several peptides of 7 and 12 amino acids with binding specificity to canine ZP proteins were identified. Four of them (LNSFLRS, SSWYRGA, YLPIYTIPSMVY, and NNQSPILKLSIH) plus a control ZP-binding peptide (YLPVGGLRRIGG) from the literature were synthesized and tested for antigenic properties in dogs. NNQSPILKLSIH peptide stimulated production of anti-peptide antibodies. These antibodies bind to the acrosomal region of the canine sperm cell, demonstrating ability to act as sperm antibodies. The identified ZP-binding peptides (mimicking sperm cell surface antigens) may be useful in the design of immunocontraceptive agents for dogs. PMID:20434854

  19. The role of androgens in species recognition and sperm production in Atlantic mollies (Poecilia mexicana).

    PubMed

    Gabor, Caitlin R; Aspbury, Andrea S; Ma, Jacqueline; Nice, Chris C

    2012-02-01

    Much is known about the role of hormones in the regulation of vertebrate mating behavior, including receptivity, and several components of mate choice. Hormones may modulate reproductive behavior in such a way to increase or decrease the individual's motivation, and therefore hormones may be important in mediating behavior associated with reproductive isolation. The mating complex of the all female gynogenetic Amazon mollies, Poecilia formosa, and their parental species (sailfin mollies, P. latipinna, and Atlantic mollies, P. mexicana) is a model system for studying ultimate mechanisms of species recognition. However, proximate mechanisms, such as variation in hormone levels, and the effect of hormones on sperm production have not been extensively examined. We predict that one or more of the sex steroid hormones in teleost fish (11-ketotestosterone (KT), testosterone (T), and estradiol (E)) will play a role in species recognition (during mate choice and/or sperm priming) for Atlantic mollies (the maternal parental species) that are sympatric with Amazon mollies. We sequentially paired male Atlantic mollies with female conspecifics and Amazon mollies and obtained water-borne hormone samples before and after mating for all fish. We measured circulating KT, T, and E from the water samples. Although we did not find an overall KT response to mating with conspecifics as has been found previously in sailfin mollies, male Atlantic mollies that mated more with conspecific females had lower postmating T levels. Additionally, males attempted to mate more with conspecific females that had lower postmating E levels, but attempted to mate more with Amazon mollies that had higher postmating KT levels. We also examined the effect of KT on sperm priming (a mechanism of premating mate choice), and found that KT levels of male Atlantic mollies prior to mating are correlated with the sperm priming response when males were paired with conspecific females, but this correlation was not

  20. Proenkephalin products are stored in the sperm acrosome and may function in fertilization.

    PubMed Central

    Kew, D; Muffly, K E; Kilpatrick, D L

    1990-01-01

    Previous studies have shown that spermatogenic cells are a major source of testicular RNA encoding the opioid peptide precursor proenkephalin, suggesting that proenkephalin-derived peptides may function as intratesticular paracrine factors produced by male germ cells. However, direct evidence for the production of proenkephalin by spermatogenic cells has been lacking. In this report, we have used polysome profile analysis, peptide quantitation, and immunocytochemistry to show that proenkephalin products are synthesized during spermatogenesis and are retained within spermatozoa of humans, hamsters, rats, and sheep. We further show that these peptides are stored in the sperm acrosome and are depleted from sperm following the acrosome reaction, an exocytotic event required for fertilization. Proenkephalin products thus may serve a dual function as sperm acrosomal factors released during the fertilization process as well as intratesticular regulators secreted by spermatogenic cells. Images PMID:1701253

  1. Role of increased male age in IVF and egg donation: is sperm DNA fragmentation responsible?

    PubMed

    Humm, Kathryn C; Sakkas, Denny

    2013-01-01

    The well documented increase in age that women conceive their first child has detracted from a similar change observed in males. As both males and females decide to conceive later, the question of whether this may impact their fertility individually and as a couple becomes even more crucial. A paternal age of over 40 years at the time of conception is a frequently quoted male age threshold, however, currently there is no clearly accepted definition of advanced paternal age or even a consensus on the implications of advancing male age. In this paper, we review some of the potential risks to the offspring of advancing male age and examine. The data available regarding pregnancy outcomes based on paternal age in both the fertile and infertile populations. Within the infertile population specifically, we examine the association between male age and outcomes based on treatment modality, including intrauterine insemination (IUI), in vitro fertilization (IVF), and donor oocyte IVF. Finally, we discuss the various mechanisms by which male age may impact sperm and fertility potential, including sperm DNA damage. PMID:23273987

  2. Ejaculate expenditure by malebush crickets decreases with sperm competition intensity

    PubMed Central

    Simmons, L. W.; Kvarnemo, C.

    1997-01-01

    Male bushcrickets transfer a spermatophore at mating that consists of a sperm-containing ampulla and a sperm-free mass, the spermatophylax, that is consumed by the female during insemination. The costs of spermatophore production for males and benefits of consumption for females result in reversals in courtship roles in nutrient limited populations that increase both the risk and intensity of sperm competition. Here we show that under conditions characteristic of courtship role reversal, male expenditure on the spermatophore is dependent on female size. When mating with small females, males increase the amount of spermatophylax material and sperm, as expected from the increased sperm competition risk associated with courtship role reversal. However, males reduce the amount of spermatophylax material and sperm transferred to larger females. Since larger females have a higher mating success when competing for nurturant males, the intensity of sperm competition covaries with female size. Reduced ejaculate expenditure under increased sperm competition intensity is in accord with theoretical expectation.

  3. Production of channel catfish with sperm cryopreserved by rapid non-equilibrium cooling.

    PubMed

    Cuevas-Uribe, Rafael; Leibo, S P; Daly, Jonathan; Tiersch, Terrence R

    2011-12-01

    -step addition. This was reflected in the flow cytometry data from which the highest membrane integrity using loops was for 20% methanol+10% methyl glycol+10% propanediol (~50%). We report the first successful sperm vitrification in fish and production of offspring from vitrified sperm in channel catfish. Although the fertilization values were low, at present this technique could nevertheless be used to reconstitute lines (especially in small aquarium fishes), but it would require improvement and scaling up before being useful as a production method for large-bodied fishes such as catfish. PMID:21896271

  4. Azoospermia and maturation arrest: malfunction of valves in erect poster of humans leads to hypoxia in sperm production site.

    PubMed

    Gat, Y; Gornish, M; Chakraborty, J; Perlow, A; Levinger, U; Pasqualotto, F

    2010-12-01

    Maturation arrest (MA) of spermatogenesis is diagnosed on histology as interruption of spermatogenesis before the final stage without impairment of Sertoli or Leydig cells. It is considered a condition of irreversible or absolute infertility. Varicocele, which represents impairment in the testicular venous drainage system, has been shown to be a bilateral disease. Malfunction of the valves increase the hydrostatic pressure in the testicular venous system that exceeds the pressure in the arterial system leading to hypoxia in the testicular microcirculation and in the seminiferous tubules, the sperm production site. Sperm production deteriorates, and ultimately progresses to azoospermia. Our prediction was that MA, if genetic factors are excluded, is the final stage of long standing hypoxia. This would indicate that MA is not always an independent disease entity, but may represent progressive process of deterioration of the testicular parenchyma beyond azoospermia. By histology and electron microscopy, our prediction confirmed, at least partially, that MA is associated with degenerative ischaemic changes in the seminiferous tubules. Adequate treatment of bilateral varicocele by microsurgery or super-selective sclerotherapy of the internal spermatic veins including associated network of venous bypasses, vertically oriented, may resume the flow of oxygenated blood. If irreversible damages did not occur and ischaemia is not too long standing, limited sperm production may be restored, at least partially. PMID:21105890

  5. Gamete Therapeutics: Recombinant Protein Adsorption by Sperm for Increasing Fertility via Artificial Insemination

    PubMed Central

    Alvarez-Gallardo, Horacio; Kjelland, Michael E.; Moreno, Juan F.; Welsh, Thomas H.; Randel, Ronald D.; Lammoglia, Miguel A.; Pérez-Martínez, Mario; Lara-Sagahón, Alma V.; Esperón-Sumano, A. Enrique; Romo, Salvador

    2013-01-01

    A decrease in fertility can have a negative economic impact, both locally and over a broader geographical scope, and this is especially the case with regard to the cattle industry. Therefore, much interest exists in evaluating proteins that might be able to increase the fertility of sperm. Heparin binding proteins (HBPs), specifically the fertility associated antigen (FAA) and the Type-2 tissue inhibitor of metalloproteinase (TIMP-2), act to favor the capacitation and acrosome reaction and perhaps even modulate the immune system’s response toward the sperm. The objective of this research was to determine the effect on fertility of adding recombinant FAA (rFAA) and recombinant TIMP-2 (rTIMP-2) to bovine semen before cryopreservation for use in an artificial insemination (AI) program in a tropical environment. For this experiment, 100 crossbred (Bos taurus x Bos indicus) heifers were selected based on their estrus cycle, body condition score (BCS), of 4 to 6 on a scale of 1 to 9, and adequate anatomical conformation evaluated by pelvic and genital (normal) measurements. Heifers were synchronized using estradiol benzoate (EB), Celosil® (PGF2α) (Shering-Plough) and a controlled internal drug release (CIDR) device was inserted that contained progesterone. Inseminations were performed in two groups at random, 50 animals per group. The control group was inseminated with conventional semen. The treatment group was inseminated with semen containing rFAA (25 µg/mL) and rTIMP-2 (25 µg/mL). In the control group a 16% pregnancy rate was obtained versus a 40% pregnancy rate for the HBP treatment group, resulting in a significant difference (P = 0.0037). Given the results herein, one may conclude that the HBPs can increase fertility and could be an option for cattle in tropical conditions; however, one needs to consider the environment, nutrition, and the genetic interaction affecting the final result in whatever reproductive program that is implemented. PMID:23762288

  6. SIGNIFICANCE OF INCORPORATING MEASURES OF SPERM PRODUCTION AND FUNCTION INTO RAT TOXICOLOGY STUDIES

    EPA Science Inventory

    The rat is the preferred species for reproductive toxicity testing. The inclusion of measures of rat sperm quality, such as motility and morphology, into reproductive test protocols often increases the sensitivity of the test to detect effects, and provides the toxicologist and ...

  7. Effects of thymoquinone on testicular structure and sperm production in male obese rats.

    PubMed

    Tüfek, Nur Hande; Altunkaynak, Muhammad Eyüp; Altunkaynak, Berrin Zuhal; Kaplan, Süleyman

    2015-01-01

    Thymoquinone (TQ) is a phytochemical compound found in the plant Nigella sativa. It has antioxidant and anti-cancer effects. This study investigated the effects of TQ on obesity and testicular structure of high-fat-diet (HFD) fed rats. Obese control (OC) and obese thymoquinone (OT) groups were fed a special diet containing 40% of total calories from fat. Non-obese control (NC) and non-thymoquinone (NT) groups were fed a standard diet for nine weeks. Then, intraperitoneal TQ injections were carried out to the OT and NT groups for six weeks and testes were removed. Catalase and myeloperoxidase activity were determined in rat testis tissue. Stereological, histopathological, and immunohistochemical changes were evaluated in the testes of the rats. In stereological studies, mean volumes of testis and seminiferous tubules, the number of spermatogenic cells and also Leydig cells in the OC group were reduced, but these values significantly increased in the OT group. Apoptotic cells were observed in the OC group in comparison to the OT group. The number of healthy sperms were reduced in the OC group, whereas the majority showed anomalies in the head, neck, and tail. The number of healthy sperm was increased and the anomalies significantly reduced by using TQ in both the NT, and especially the OT group. TQ like antioxidants may improve fertility by means of increasing the healthy sperm number and preventing sperm anomalies. PMID:26043060

  8. Sperm competition leads to functional adaptations in avian testes to maximize sperm quantity and quality.

    PubMed

    Lüpold, Stefan; Wistuba, Joachim; Damm, Oliver S; Rivers, James W; Birkhead, Tim R

    2011-05-01

    The outcome of sperm competition (i.e. competition for fertilization between ejaculates from different males) is primarily determined by the relative number and quality of rival sperm. Therefore, the testes are under strong selection to maximize both sperm number and quality, which are likely to result in trade-offs in the process of spermatogenesis (e.g. between the rate of spermatogenesis and sperm length or sperm energetics). Comparative studies have shown positive associations between the level of sperm competition and both relative testis size and the proportion of seminiferous (sperm-producing) tissue within the testes. However, it is unknown how the seminiferous tissue itself or the process of spermatogenesis might evolve in response to sperm competition. Therefore, we quantified the different germ cell types and Sertoli cells (SC) in testes to assess the efficiency of sperm production and its associations with sperm length and mating system across 10 species of New World Blackbirds (Icteridae) that show marked variation in sperm length and sperm competition level. We found that species under strong sperm competition generate more round spermatids (RS)/spermatogonium and have SC that support a greater number of germ cells, both of which are likely to increase the maximum sperm output. However, fewer of the RS appeared to elongate to mature spermatozoa in these species, which might be the result of selection for discarding spermatids with undesirable characteristics as they develop. Our results suggest that, in addition to overall size and gross morphology, testes have also evolved functional adaptations to maximize sperm quantity and quality. PMID:21307271

  9. Direct action of endocrine disrupting chemicals on human sperm.

    PubMed

    Schiffer, Christian; Müller, Astrid; Egeberg, Dorte L; Alvarez, Luis; Brenker, Christoph; Rehfeld, Anders; Frederiksen, Hanne; Wäschle, Benjamin; Kaupp, U Benjamin; Balbach, Melanie; Wachten, Dagmar; Skakkebaek, Niels E; Almstrup, Kristian; Strünker, Timo

    2014-07-01

    Synthetic endocrine disrupting chemicals (EDCs), omnipresent in food, household, and personal care products, have been implicated in adverse trends in human reproduction, including infertility and increasing demand for assisted reproduction. Here, we study the action of 96 ubiquitous EDCs on human sperm. We show that structurally diverse EDCs activate the sperm-specific CatSper channel and, thereby, evoke an intracellular Ca(2+) increase, a motility response, and acrosomal exocytosis. Moreover, EDCs desensitize sperm for physiological CatSper ligands and cooperate in low-dose mixtures to elevate Ca(2+) levels in sperm. We conclude that EDCs interfere with various sperm functions and, thereby, might impair human fertilization. PMID:24820036

  10. Direct action of endocrine disrupting chemicals on human sperm

    PubMed Central

    Schiffer, Christian; Müller, Astrid; Egeberg, Dorte L; Alvarez, Luis; Brenker, Christoph; Rehfeld, Anders; Frederiksen, Hanne; Wäschle, Benjamin; Kaupp, U Benjamin; Balbach, Melanie; Wachten, Dagmar; Skakkebaek, Niels E; Almstrup, Kristian; Strünker, Timo

    2014-01-01

    Synthetic endocrine disrupting chemicals (EDCs), omnipresent in food, household, and personal care products, have been implicated in adverse trends in human reproduction, including infertility and increasing demand for assisted reproduction. Here, we study the action of 96 ubiquitous EDCs on human sperm. We show that structurally diverse EDCs activate the sperm-specific CatSper channel and, thereby, evoke an intracellular Ca2+ increase, a motility response, and acrosomal exocytosis. Moreover, EDCs desensitize sperm for physiological CatSper ligands and cooperate in low-dose mixtures to elevate Ca2+ levels in sperm. We conclude that EDCs interfere with various sperm functions and, thereby, might impair human fertilization. PMID:24820036

  11. Small testicles with impaired production of sperm in adult male survivors of childhood malignancies

    SciTech Connect

    Siimes, M.A.; Rautonen, J. )

    1990-03-15

    Testicular size has been studied in 66 adult men who survived leukemia (n = 14) or cancer (n = 52) in childhood. Mean follow-up time was 14.5 years. The testicular size was measured as the length and breadth in mm; testicular volume index was calculated. Serum concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone, and prolactin were measured. A sperm sample was obtained from 46 men. The patients had smaller testicles than healthy medical students; 51 had small testicles. The size was the smallest in patients who survived leukemia. Multivariate analysis showed that the variables with independent effects on testicular size were cranial and testicular irradiation and therapy with cyclophosphamide. Sperm production was dependent on testicular size. We conclude that determination of serum FSH combined with testicular size may offer a practical approach for predicting the subsequent testicular damage in boys with malignancies.

  12. Performance of Rodent Spermatozoa Over Time Is Enhanced by Increased ATP Concentrations: The Role of Sperm Competition.

    PubMed

    Tourmente, Maximiliano; Villar-Moya, Pilar; Varea-Sánchez, María; Luque-Larena, Juan J; Rial, Eduardo; Roldan, Eduardo R S

    2015-09-01

    Sperm viability, acrosome integrity, motility, and swimming velocity are determinants of male fertility and exhibit an extreme degree of variation among closely related species. Many of these sperm parameters are associated with sperm ATP content, which has led to predictions of trade-offs between ATP content and sperm motility and velocity. Selective pressures imposed by sperm competition have been proposed as evolutionary causes of this pattern of diversity in sperm traits. Here, we examine variation in sperm viability, acrosome integrity, motility, swimming velocity, and ATP content over time, among 18 species of closely related muroid rodents, to address the following questions: (a) Do sperm from closely related species vary in ATP content after a period of incubation? (b) Are these differences in ATP levels related to differences in other sperm traits? (c) Are differences in ATP content and sperm performance over time explained by the levels of sperm competition in these species? Our results revealed a high degree of interspecific variability in changes in sperm ATP content, acrosome integrity, sperm motility and swimming velocity over time. Additionally, species with high sperm competition levels were able to maintain higher levels of sperm motility and faster sperm swimming velocity when they were incubated under conditions that support sperm survival. Furthermore, we show that the maintenance of such levels of sperm performance is correlated with the ability of sperm to sustain high concentrations of intracellular ATP over time. Thus, sperm competition may have an important role maximizing sperm metabolism and performance and, ultimately, the fertilizing capacity of spermatozoa. PMID:26157072

  13. Application of a microfluidic sperm sorter to in vitro production of dairy cattle sex-sorted embryos.

    PubMed

    Li, Jingchun; Zhu, Sibing; He, Xianjing; Sun, Rui; He, Qianyu; Gan, Yi; Liu, Shengjun; Funahashi, Hiroaki; Li, Yanbing

    2016-04-15

    Viable sperm from sex-sorted semen without centrifugal treatment was separated by a microfluidic sperm sorter (MFSS) for IVF to improve in vitro embryo production of dairy cattle. The MFSS was originally developed to isolate motile human sperm by two laminar flows in the micro-channel (there are four chambers in an MFSS. Chamber A is the inlet for semen, chamber B is the inlet for the medium, chamber C is the exit chamber for motile sperm, and chamber D is the outlet for nonmotile sperm). Sex-sorted sperm were adjusted to 1 × 10(7) spermatozoa/mL (2 million cells/dose, sperm motility was 30% above after thawing). In a first experiment, diluted sex-sorted semen was mixed with modified Medium199(mM199) containing 5-mM caffeine for 5 minutes, resulting in variations in sperm concentration and quality parameters at chambers A, C, and D. In a second experiment, medium containing sperm from three MFSS chambers was collected and mitochondrial activity of the sperm was determined by flow cytometry, the relative activity of sperm mitochondria in chamber C (1.56 ± 0.03) was the highest in three observation areas (P < 0.05). Thus, sperm motility and mitochondrial activity of sperm was high in chamber C. In a third experiment, different concentrations of sperm were added to chamber A and dairy cattle IVM oocytes were placed in chamber C, where motile spermatozoa will accumulate, with mM199 containing 5-mM caffeine for 5 minutes, and then cultured in caffeine-free mM199 for 8 hours. The results showed that sperm penetration rate, the monospermic penetration rate, and blastocyst rate of the 10 × 10(6) group (10 × 10(6) sperm/mL) were higher than in the 1 × 10(6) and 5 × 10(6) groups (P < 0.05). In the last experiment, we compared sperm penetration in the MFSS-IVF system with a modified standard IVF method (cocultured in droplets for 8 hours). The normal fertilization index (the ratio of monospermic oocytes to the number of oocytes examined) 8

  14. Electroejaculation increases low molecular weight proteins in seminal plasma modifying sperm quality in Corriedale rams.

    PubMed

    Ledesma, A; Manes, J; Cesari, A; Alberio, R; Hozbor, F

    2014-04-01

    This study was conducted to evaluate the effect of seminal collection method (artificial vagina or electroejaculation) on the protein composition of seminal plasma and sperm quality parameters in Corriedale rams. To address this question, we assessed the effect of seminal collection method on motility, plasma membrane integrity and functionality, mitochondrial functionality and the decondensation state of nuclear chromatin in sperm cells. Volume, pH, osmolarity, protein concentration, total protein content and protein profile using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and 2-D polyacrylamide electrophoresis of seminal plasma collected with artificial vagina and electroejaculation were also analysed. The main findings from this study were that ejaculates obtained with electroejaculation had (i) a higher number of spermatozoa with intact plasma membrane and functional mitochondria and (ii) a higher proportion of seminal plasma, total protein content and relative abundance of low molecular weight proteins than ejaculates obtained with artificial vagina. Five of these proteins were identified by mass spectrometry: binder of sperm 5 precursor; RSVP14; RSVP22; epididymal secretory protein E1 and clusterin. One protein spot with molecular weight of approximately 31 kDa and isoelectric point of 4.8 was only found in the seminal plasma from electroejaculation. PMID:24494601

  15. Application study of intracytoplasmic sperm injection for golden hamster and cattle production.

    PubMed

    Horiuchi, Toshitaka

    2006-02-01

    This paper describes several technical improvements and our results in hamster intracytoplasmic sperm injection (ICSI), hamster round spermatid injection (ROSI) and bovine ICSI. The hamster is the mammalian species in which ICSI was first tried to produce fertilized oocytes. However, until recently, no live offspring following ICSI have ever been obtained. We reported the birth of live offspring following hamster ICSI. Improved points to success were 1) performing hamster ICSI in a dark room with a small incandescent lamp and manipulating both oocytes and fertilized eggs under microscope with a red light source and 2) injecting sperm heads without acrosomes. Under controlled illumination, the majority of the oocytes injected with acrosomeless sperm heads were fertilized normally, cleaved, and developed into morulae. Nine live offspring (19%) were born by transfer of hamster ICSI-derived embryos. Furthermore, we reported the birth of live offspring following hamster ROSI. About 70% of oocytes injected with round spermatids broken before injection were fertilized normally and about half of them developed to morulae and blastocysts. Three (5%) live young were born by transfer of hamster ROSI-derived embryos. On the other hand, in cattle, the main improvements were 1) injection of spermatozoa immobilized by scoring their tail just before injection into oocytes, and 2) additional ethanol activation 4 h after ICSI. About 70% of oocytes injected were activated 4 h after ICSI, and about 30% of them developed to blastocysts. Twenty-four live calves (39%) were born by non-surgical transfer of ICSI-derived embryos. Those results shows that, at present, live offspring are able to be obtained following hamster ICSI, ROSI and bovine ICSI, but further improvement is required due to higher production efficiency of offspring. PMID:16538031

  16. Production of F1 interspecies hybrid offspring with cryopreserved sperm from a live-bearing fish, the swordtail Xiphophorus helleri.

    PubMed

    Yang, Huiping; Hazlewood, Leona; Heater, Sheila J; Guerrero, Paula A; Walter, Ronald B; Tiersch, Terrence R

    2007-03-01

    Despite study of sperm cryopreservation in more than 200 fish species, production of broods from cryopreserved sperm in live-bearing fish has not been demonstrated. This has not been due to a lack of effort, but instead is a result of the unique morphology, biology, and biochemistry of reproduction in viviparous fishes. For example, sperm of Xiphophorus helleri have a cylindrical nucleus, can swim for days after being activated, have glycolytic capabilities, and can reside in the female reproduction tract for months before fertilization. These traits are not found in fishes with external fertilization. The long-standing research use of the genus Xiphophorus has led to development of over 60 pedigreed lines among the 26 species maintained around the world. These species and lines serve as contemporary models in medical research, although they must be maintained as live populations. Previous attempts at establishing sperm cryopreservation protocols for Xiphophorus have not produced live young. To address this we have been studying the parameters surrounding cryobiology of Xiphophorus sperm and applying this information to an improved understanding of internal fertilization and reproduction. Here we report the first successful fertilization and offspring production by cryopreserved sperm in any live-bearing fish. This claim is supported by our use of artificial insemination between two species that yield distinct hybrid offspring to verify paternity via cryopreserved sperm. We provide a practical approach for preservation of valuable genetic resources from live-bearing fish species, a group that is rapidly being lost due to destruction of native habitats. PMID:17108333

  17. Methods for evaluating the effects of environmental chemicals on human sperm production

    SciTech Connect

    Wyrobek, A.J.

    1982-04-20

    Sperm tests provide a direct and effective way of identifying chemical agents that induce spermatogenic damage in man. Four human sperm tests are available: sperm count, motility, morphology (seminal cytology), and the Y-body test. These sperm tests have numerous advantages over other approaches for assessing spermatogenic damage, and they have already been used to assess the effects of at least 85 different occupational, envionmental, and drug-related chemical exposures. When carefully controlled, seminal cytology appears to be statistically more sensitive than the other human sperm tests and should be considered an integral part of semen analysis when assessing induced spermatogenic damage.

  18. The secretory products of Trichomonas vaginalis decrease fertilizing capacity of mice sperm in vitro.

    PubMed

    Roh, Jaesook; Lim, Young-Su; Seo, Min-Young; Choi, Yuri; Ryu, Jae-Sook

    2015-01-01

    Trichomonas vaginalis infection is one of the most prevalent sexually transmitted infections in humans and is now recognized as an important cause of infertility in men. There is little information about the effect of extracellular polymeric substances (EPS) from T. vaginalis on sperm, but previous reports do not provide a conclusive description of the functional integrity of the sperm. To investigate the impact of EPS on the fertilizing capacity of sperm, we assessed sperm motility, acrosomal status, hypo-osmotic swelling, and in vitrofertilization rate after incubating the sperm with EPS in vitrousing mice. The incubation of sperm with EPS significantly decreased sperm motility, viability, and functional integrity in a concentration and time-dependent manner. These effects on sperm quality also resulted in a decreased fertilization rate in vitro. This is the first report that demonstrates the direct negative impact of the EPS of T. vaginalis on the fertilization rate of sperm in vitro. However, further study should be performed using human sperm to determine if EPS has similar negative impact on human sperm fertilizing capacity in vitro. PMID:25578937

  19. Male-biased sex ratio does not promote increased sperm competitiveness in the seed beetle, Callosobruchus maculatus

    PubMed Central

    McNamara, Kathryn B.; Robinson, Stephen P.; Rosa, Márta E.; Sloan, Nadia S.; van Lieshout, Emile; Simmons, Leigh W.

    2016-01-01

    Sperm competition risk and intensity can select for adaptations that increase male fertilisation success. Evolutionary responses are examined typically by generating increased strength of sexual selection via direct manipulation of female mating rates (by enforcing monandry or polyandry) or by alteration of adult sex ratios. Despite being a model species for sexual selection research, the effect of sexual selection intensity via adult sex-ratio manipulation on male investment strategies has not been investigated in the seed beetle, Callosobruchus maculatus. We imposed 32 generations of experimental evolution on 10 populations of beetles by manipulating adult sex ratio. Contrary to predictions, males evolving in male-biased populations did not increase their testes and accessory gland size. This absence of divergence in ejaculate investment was also reflected in the fact that males from male-biased populations were not more successful in either preventing females from remating, or in competing directly for fertilisations. These populations already demonstrate divergence in mating behaviour and immunity, suggesting sufficient generations have passed to allow divergence in physiological and behavioural traits. We propose several explanations for the absence of divergence in sperm competitiveness among our populations and the pitfalls of using sex ratio manipulation to assess evolutionary responses to sexual selection intensity. PMID:27306351

  20. Male-biased sex ratio does not promote increased sperm competitiveness in the seed beetle, Callosobruchus maculatus.

    PubMed

    McNamara, Kathryn B; Robinson, Stephen P; Rosa, Márta E; Sloan, Nadia S; van Lieshout, Emile; Simmons, Leigh W

    2016-01-01

    Sperm competition risk and intensity can select for adaptations that increase male fertilisation success. Evolutionary responses are examined typically by generating increased strength of sexual selection via direct manipulation of female mating rates (by enforcing monandry or polyandry) or by alteration of adult sex ratios. Despite being a model species for sexual selection research, the effect of sexual selection intensity via adult sex-ratio manipulation on male investment strategies has not been investigated in the seed beetle, Callosobruchus maculatus. We imposed 32 generations of experimental evolution on 10 populations of beetles by manipulating adult sex ratio. Contrary to predictions, males evolving in male-biased populations did not increase their testes and accessory gland size. This absence of divergence in ejaculate investment was also reflected in the fact that males from male-biased populations were not more successful in either preventing females from remating, or in competing directly for fertilisations. These populations already demonstrate divergence in mating behaviour and immunity, suggesting sufficient generations have passed to allow divergence in physiological and behavioural traits. We propose several explanations for the absence of divergence in sperm competitiveness among our populations and the pitfalls of using sex ratio manipulation to assess evolutionary responses to sexual selection intensity. PMID:27306351

  1. Methods for evaluating the effects of environmental chemicals on human sperm production.

    PubMed Central

    Wyrobek, A J

    1983-01-01

    Sperm tests provide a direct and effective way of identifying chemical agents that induce spermatogenic damage in man. Four human sperm tests are available: sperm count, motility, morphology (seminal cytology) and the Y-body test. These sperm tests have numerous advantages over other approaches for assessing spermatogenic damage, and they have already been used to assess the effects of at least 85 different occupational, environmental, and drug-related chemical exposures. When carefully controlled, seminal cytology appears to be statistically more sensitive than the other human sperm tests and should be considered an integral part of semen analysis when assessing induced spermatogenic damage. Human sperm studies have complex requirements and, before sampling, careful consideration should be given to exposure details, group size and makeup, as well as animal and human data that indicate spermatogenic effects. Several study designs are possible and should include questionnaires covering medical and reproductive histories as well as known confounding factors. Animal sperm tests, such as the mouse morphology test, may be used to identify the toxic components of a complex mixture. Animal tests may also help assess the chemical effects on fertility and reproductive outcome in cases when human data are incomplete. Further efforts are needed in these areas to develop improved human sperm tests sensitive to induced spermatogenic damage, to develop improved animal models of induced spermatogenic damage, to understand the relationships among sperm changes, fertility, and reproductive outcome, and to develop sperm tests with express mutational end points. PMID:6825635

  2. Production of F1 Offspring with Vitrified Sperm from a Live-Bearing Fish, the Green Swordtail Xiphophorus hellerii

    PubMed Central

    Cuevas-Uribe, Rafael; Yang, Huiping; Daly, Jonathan; Savage, Markita G.; Walter, Ronald B.

    2011-01-01

    Abstract This study reports the first production of offspring with vitrified sperm from a live-bearing fish Xiphophorus hellerii. The overall goal of this study was to develop streamlined protocols for integration into a standardized approach for vitrification of aquatic species germplasm. The objectives were to (1) estimate acute toxicity of cryoprotectants, (2) evaluate vitrification solutions, (3) compare different thawing methods, (4) evaluate membrane integrity of post-thaw sperm vitrified in different cryoprotectants, and (5) evaluate the fertility of vitrified sperm. Nine cryoprotectants and two commercial vitrification additives were tested for acute toxicity and glass forming ability, alone and in combination. Two vitrification solutions, 40% glycerol (Gly) and 20% Gly+20% ethylene glycol (EG) in 500 mOsmol/kg Hanks' balanced salt solution (HBSS), were selected for vitrification of 10 μL sperm samples using inoculating loops plunged into liquid nitrogen. Samples were thawed at 24°C (one loop in 5 μL of HBSS or three loops in 500 μL of HBSS). Samples thawed in 500 μL were concentrated by centrifugation (1000 g for 5 min at 4°C) into 5 μL for artificial insemination. Offspring were produced from virgin females inseminated with sperm vitrified with 20% Gly+20% EG and concentrated by centrifugation. PMID:21883000

  3. Effect of Ca Ionophore On Blastocyst Production Following Intracytoplasmic Sperm Injection in Caprine Oocytes.

    PubMed

    Kharche, S D; Pathak, J; Agarwal, S; Kushwah, B; Sikarwar, Aks

    2016-08-01

    The aim of the present investigation was to study the effect of calcium ionophore activation on blastocyst production following intracytoplasmic sperm injection (ICSI) in in vitro-matured Caprine oocytes. A total of 470 in vitro-matured oocytes were selected and randomly divided in to three groups. Cumulus oocyte complexes (COCs) recovered by slicing the Caprine ovaries were matured in TCM199 supplemented with 10% foetal bovine serum (FBS) + 10% follicular fluid + FSH (5 μg/ml) + LH (10 μg/ml) + estradiol (1 μg/ml) + EGF (10 ng/ml) + BSA (3 mg/ml) for 27 h in humidified atmosphere at 38.5°C with 5% CO2 in CO2 incubator. After 27 h of culture, selected COCs (n = 470) were separated from cumulus cells by treating with 0.1% hyaluronidase enzyme and passing repeatedly through a fine pipette and randomly divided into three groups. In group 1, (n = 168) matured oocytes were injected with injection micropipette without sperm as control. In group 2, (n = 152) capacitated spermatozoa were injected into cytoplasm of in vitro-matured oocytes through injection micropipette. In group 3, (n = 150) capacitated spermatozoa were injected into cytoplasm of in vitro-matured oocytes through injection micropipette and then activated with 5 μm Ca ionophore for 5 min. The oocytes of all groups were then culture in RVCL media for embryo development. The cleavage rate was observed after 48-72 h of injection. The cleavage rate and blastocyst production in group 1, 2 and 3 were 0.00 and 0.00, 18.42 and 3.57 and 61.33% and 16.30%, respectively. The result indicated that mechanical activation failed to induce cleavage in in vitro-matured Caprine oocytes, whereas chemical activation of intracytoplasmic sperm-injected in vitro-matured Caprine oocytes showed significantly higher cleavage rate and blastocyst production as compare to non-activated oocytes. PMID:27170442

  4. Procurement of exogenous ammonia by the swallowtail butterfly, Papilio polytes, for protein biosynthesis and sperm production

    NASA Astrophysics Data System (ADS)

    Honda, Keiichi; Takase, Hiroyuki; Ômura, Hisashi; Honda, Hiroshi

    2012-09-01

    How to acquire sufficient quantity of nitrogen is a pivotal issue for herbivores, particularly for lepidopterans (butterflies and moths) of which diet quality greatly differs among their life stages. Male Lepidoptera often feed from mud puddles, dung, and carrion, a behavior known as puddling, which is thought to be supplementary feeding targeted chiefly at sodium. During copulation, males transfer a spermatophore to females that contains, besides sperm, nutrients (nuptial gifts) rich in sodium, proteins, and amino acids. However, it is still poorly understood how adults, mostly nectarivores, extract nitrogen from the environment. We examined the availability of two ubiquitous inorganic nitrogenous ions in nature, viz. ammonium (or ammonia) and nitrate ions, as nutrients in a butterfly, and show that exogenous ammonia ingested by adult males of the swallowtail, Papilio polytes, can serve as a resource for protein biosynthesis. Feeding experiments with 15N-labeled ammonium chloride revealed that nitrogen was incorporated into eupyrene spermatozoa, seminal protein, and thoracic muscle. Ammonia uptake by males significantly increased the number of eupyrene sperms in the reproductive tract tissues. The females also had the capacity to assimilate ammonia into egg protein. Consequently, it is evident that acquired ammonia is utilized for the replenishment of proteins allocable for reproduction and somatic maintenance. The active exploitation of exogenous ammonia as a nutrient by a butterfly would foster better understanding of the foraging and reproductive strategies in insects.

  5. Production of Diabetic Offspring Using Cryopreserved Epididymal Sperm by In Vitro Fertilization and Intrafallopian Insemination Techniques in Transgenic Pigs

    PubMed Central

    UMEYAMA, Kazuhiro; HONDA, Kasumi; MATSUNARI, Hitomi; NAKANO, Kazuaki; HIDAKA, Tatsuro; SEKIGUCHI, Keito; MOCHIZUKI, Hironori; TAKEUCHI, Yasuhiro; FUJIWARA, Tsukasa; WATANABE, Masahito; NAGAYA, Masaki; NAGASHIMA, Hiroshi

    2013-01-01

    Abstract Somatic cell nuclear transfer (SCNT) is a useful technique for creating pig strains that model human diseases. However, production of numerous cloned disease model pigs by SCNT for large-scale experiments is impractical due to its complexity and inefficiency. In the present study, we aimed to establish an efficient procedure for proliferating the diabetes model pig carrying the mutant human hepatocyte nuclear factor-1α gene. A founder diabetes transgenic cloned pig was generated by SCNT and treated with insulin to allow for normal growth to maturity, at which point epididymal sperm could be collected for cryopreservation. In vitro fertilization and intrafallopian insemination using the cryopreserved epididymal sperm resulted in diabetes model transgenic offspring. These results suggest that artificial reproductive technology using cryopreserved epididymal sperm could be a practical option for proliferation of genetically modified disease model pigs. PMID:23979397

  6. Production of diabetic offspring using cryopreserved epididymal sperm by in vitro fertilization and intrafallopian insemination techniques in transgenic pigs.

    PubMed

    Umeyama, Kazuhiro; Honda, Kasumi; Matsunari, Hitomi; Nakano, Kazuaki; Hidaka, Tatsuro; Sekiguchi, Keito; Mochizuki, Hironori; Takeuchi, Yasuhiro; Fujiwara, Tsukasa; Watanabe, Masahito; Nagaya, Masaki; Nagashima, Hiroshi

    2013-12-17

    Somatic cell nuclear transfer (SCNT) is a useful technique for creating pig strains that model human diseases. However, production of numerous cloned disease model pigs by SCNT for large-scale experiments is impractical due to its complexity and inefficiency. In the present study, we aimed to establish an efficient procedure for proliferating the diabetes model pig carrying the mutant human hepatocyte nuclear factor-1α gene. A founder diabetes transgenic cloned pig was generated by SCNT and treated with insulin to allow for normal growth to maturity, at which point epididymal sperm could be collected for cryopreservation. In vitro fertilization and intrafallopian insemination using the cryopreserved epididymal sperm resulted in diabetes model transgenic offspring. These results suggest that artificial reproductive technology using cryopreserved epididymal sperm could be a practical option for proliferation of genetically modified disease model pigs. PMID:23979397

  7. Redox regulation of mammalian sperm capacitation

    PubMed Central

    O’Flaherty, Cristian

    2015-01-01

    Capacitation is a series of morphological and metabolic changes necessary for the spermatozoon to achieve fertilizing ability. One of the earlier happenings during mammalian sperm capacitation is the production of reactive oxygen species (ROS) that will trigger and regulate a series of events including protein phosphorylation, in a time-dependent fashion. The identity of the sperm oxidase responsible for the production of ROS involved in capacitation is still elusive, and several candidates are discussed in this review. Interestingly, ROS-induced ROS formation has been described during human sperm capacitation. Redox signaling during capacitation is associated with changes in thiol groups of proteins located on the plasma membrane and subcellular compartments of the spermatozoon. Both, oxidation of thiols forming disulfide bridges and the increase on thiol content are necessary to regulate different sperm proteins associated with capacitation. Reducing equivalents such as NADH and NADPH are necessary to support capacitation in many species including humans. Lactate dehydrogenase, glucose-6-phospohate dehydrogenase, and isocitrate dehydrogenase are responsible in supplying NAD (P) H for sperm capacitation. Peroxiredoxins (PRDXs) are newly described enzymes with antioxidant properties that can protect mammalian spermatozoa; however, they are also candidates for assuring the regulation of redox signaling required for sperm capacitation. The dysregulation of PRDXs and of enzymes needed for their reactivation such as thioredoxin/thioredoxin reductase system and glutathione-S-transferases impairs sperm motility, capacitation, and promotes DNA damage in spermatozoa leading to male infertility. PMID:25926608

  8. [How to increase food production?].

    PubMed

    Gahamanyi, L

    1984-12-01

    Pressure of population on cultivable land, serious soil erosion, and low productivity due to scarcity of inputs have hampered efforts to provide an adequate diet for the population of Rwanda. Until the present, production has increased about as rapidly as population, but Rwanda is not totally self-sufficient in food, future climatic conditions may be less favorable than those of the past, technical and resource constraints are likely to increase, and little new land will be available for cultivation. Between 1970-80, hectares devoted to bananas and beans have increased considerably, but the marginal nature of much new land has seriously lowered productivity. Sweet potatoes are more extensively grown but their productivity is limited, and productivity of manioc has stagnated despite efforts to increase it. Peas are less frequently cultivated because the fallow land on they they are grown has almost disappeared due to population pressure. Agriculture in Rwanda has always been associated with herding, but population pressure is eliminating pastureland. Firewood for cooking is also becoming more scarce and reforestation is not proceeding rapidly enough to fill projected demand. Between 1978-80 and the year 2000, preliminary goals are to increase production in tons from 2,005,900 to 3,375,000 for bananas, from 177,400 to 330,000 for beans, from 15,200 to 45,500 for ground nuts, from 4000 to 25,000 for soybeans, from 174,800 to 288,000 for sorghum, from 81,300 to 250,000 for maize, from 3700 to 45,000 for rice, from 837,100 to 2,148,000 for sweet potatoes, from 506,600 to 1,200,000 for manioc, and from 216,000 to 600,000 for potatoes. Reaching these goals will require doubling of overall productivity per hectare. Different strategies will be required for increasing the yields of the principal crops. Priority should be given to developing strains of beans that will grow well in the poor soils, dry or cold regions, and acidic soils where they are usually planted in Rwanda

  9. Increase Productivity Through Knowledge Management

    NASA Astrophysics Data System (ADS)

    Gavrikova, N. A.; Dolgih, I. N.; Dyrina, E. N.

    2016-04-01

    Increase in competition level requires companies to improve the efficiency of work force use characterized by labor productivity. Professional knowledge of staff and its experience play the key role in it. The results of Extrusion Line operator’s working time analysis are performed in this article. The analysis revealed that the reasons of working time ineffective use connected with inadequate information exchange and knowledge management in the company. Authors suggest the way to solve this problem: the main sources of knowledge in engineering enterprise have been defined, the conditions of success and the stages of knowledge management control have been stated.

  10. A Quality Assurance Initiative for Commercial-Scale Production in High-Throughput Cryopreservation of Blue Catfish Sperm

    PubMed Central

    Hu, E; Liao, T. W.; Tiersch, T. R.

    2013-01-01

    Cryopreservation of fish sperm has been studied for decades at a laboratory (research) scale. However, high-throughput cryopreservation of fish sperm has recently been developed to enable industrial-scale production. This study treated blue catfish (Ictalurus furcatus) sperm high-throughput cryopreservation as a manufacturing production line and initiated quality assurance plan development. The main objectives were to identify: 1) the main production quality characteristics; 2) the process features for quality assurance; 3) the internal quality characteristics and their specification designs; 4) the quality control and process capability evaluation methods, and 5) the directions for further improvements and applications. The essential product quality characteristics were identified as fertility-related characteristics. Specification design which established the tolerance levels according to demand and process constraints was performed based on these quality characteristics. Meanwhile, to ensure integrity throughout the process, internal quality characteristics (characteristics at each quality control point within process) that could affect fertility-related quality characteristics were defined with specifications. Due to the process feature of 100% inspection (quality inspection of every fish), a specific calculation method, use of cumulative sum (CUSUM) control charts, was applied to monitor each quality characteristic. An index of overall process evaluation, process capacity, was analyzed based on in-control process and the designed specifications, which further integrates the quality assurance plan. With the established quality assurance plan, the process could operate stably and quality of products would be reliable. PMID:23872356

  11. Environmental chemicals impact dog semen quality in vitro and may be associated with a temporal decline in sperm motility and increased cryptorchidism

    PubMed Central

    Lea, Richard G.; Byers, Andrew S.; Sumner, Rebecca N.; Rhind, Stewart M.; Zhang, Zulin; Freeman, Sarah L.; Moxon, Rachel; Richardson, Holly M.; Green, Martin; Craigon, Jim; England, Gary C. W.

    2016-01-01

    Adverse temporal trends in human semen quality and cryptorchidism in infants have been associated with exposure to environmental chemicals (ECs) during development. Here we report that a population of breeding dogs exhibit a 26 year (1988–2014) decline in sperm quality and a concurrent increased incidence of cryptorchidism in male offspring (1995–2014). A decline in the number of males born relative to the number of females was also observed. ECs, including diethylhexyl phthalate (DEHP) and polychlorinated bisphenol 153 (PCB153), were detected in adult dog testes and commercial dog foods at concentrations reported to perturb reproductive function in other species. Testicular concentrations of DEHP and PCB153 perturbed sperm viability, motility and DNA integrity in vitro but did not affect LH stimulated testosterone secretion from adult testis explants. The direct effects of chemicals on sperm may therefore contribute to the decline in canine semen quality that parallels that reported in the human. PMID:27503122

  12. Environmental chemicals impact dog semen quality in vitro and may be associated with a temporal decline in sperm motility and increased cryptorchidism.

    PubMed

    Lea, Richard G; Byers, Andrew S; Sumner, Rebecca N; Rhind, Stewart M; Zhang, Zulin; Freeman, Sarah L; Moxon, Rachel; Richardson, Holly M; Green, Martin; Craigon, Jim; England, Gary C W

    2016-01-01

    Adverse temporal trends in human semen quality and cryptorchidism in infants have been associated with exposure to environmental chemicals (ECs) during development. Here we report that a population of breeding dogs exhibit a 26 year (1988-2014) decline in sperm quality and a concurrent increased incidence of cryptorchidism in male offspring (1995-2014). A decline in the number of males born relative to the number of females was also observed. ECs, including diethylhexyl phthalate (DEHP) and polychlorinated bisphenol 153 (PCB153), were detected in adult dog testes and commercial dog foods at concentrations reported to perturb reproductive function in other species. Testicular concentrations of DEHP and PCB153 perturbed sperm viability, motility and DNA integrity in vitro but did not affect LH stimulated testosterone secretion from adult testis explants. The direct effects of chemicals on sperm may therefore contribute to the decline in canine semen quality that parallels that reported in the human. PMID:27503122

  13. Lactate and Pyruvate Are Major Sources of Energy for Stallion Sperm with Dose Effects on Mitochondrial Function, Motility, and ROS Production.

    PubMed

    Darr, Christa R; Varner, Dickson D; Teague, Sheila; Cortopassi, Gino A; Datta, Sandipan; Meyers, Stuart A

    2016-08-01

    Stallion sperm rely primarily on oxidative phosphorylation for production of ATP used in sperm motility and metabolism. The objective of the study was to identify which substrates included in Biggers, Whitten, and Whittingham (BWW) media are key to optimal mitochondrial function through measurements of sperm motility parameters, mitochondrial oxygen consumption, and cellular reactive oxygen species (ROS) production. It was expected that mitochondrial substrates, pyruvate and lactate, would support sperm motility and mitochondrial function better than the glycolytic substrate, glucose, due to direct utilization within the mitochondria. Measurements were performed after incubation in modified BWW media with varying concentrations of lactate, pyruvate, and glucose. The effects of media and duration of incubation on sperm motility, ROS production, and oxygen consumption were determined using a linear mixed-effects model. Duplicate ejaculates from four stallions were used in three separate experiments to determine the effects of substrate availability and concentration on sperm motility and mitochondrial function and the relationship of oxygen consumption with cellular ROS production. The present results indicate that lactate and pyruvate are the most important sources of energy for stallion sperm motility and velocity, and elicit a dose-dependent response. Additionally, lactate and pyruvate are ideal for maximal mitochondrial function, as sperm in these media operate at a very high level of their bioenergetic capability due to the high rate of energy metabolism. Moreover, we found that addition of glucose to the media is not necessary for short-term storage of equine sperm, and may even result in reduction of mitochondrial function. Finally, we have confirmed that ROS production can be the result of mitochondrial dysfunction as well as intense mitochondrial activity. PMID:27335066

  14. In vitro production of cattlexbuffalo hybrid embryos using cattle oocytes and African buffalo (Syncerus caffer caffer) epididymal sperm.

    PubMed

    Owiny, O D; Barry, D M; Agaba, M; Godke, R A

    2009-04-01

    Interspecies hybridization of bovids occurs between domestic cattle and at least three other species; American bison (Bison bison), yak (Bos grunniens) and banteng (Bos banteng). Birth of a cattlexbuffalo (Bubalus bubalis) hybrid has reportedly occurred in Russia and in China, but these reports were not authenticated. Such hybrids could be important in improving livestock production and management of diseases that impede production in tropical Africa. This study investigated hybridization between cattle and its closest African wild bovid relative, the African buffalo (Syncerus caffer caffer). In an attempt to produce cattlexbuffalo hybrid embryos in vitro, matured cattle oocytes were subjected to a standard in vitro fertilization (IVF) procedure with either homologous cattle (n=1166 oocytes) or heterologous African buffalo (n=1202 oocytes) frozen-thawed epididymal sperm. After IVF, 67.2% of the oocytes inseminated with the homologous cattle sperm cleaved. In contrast, fertilization with buffalo sperm resulted in only a 4.6% cleavage rate. The cleavage intervals were also slower in hybrid embryos than in the IVF-derived cattle embryos. Of the cleaved homologous cattle embryos 52.2% progressed to the morula stage compared with 12.7% for the buffalo hybrid embryos. No hybrid embryos developed beyond the early morula stage, while 40.1% of the cleaved cattlexcattle embryos developed to the blastocyst stage. Transfer of buffalo hybrid IVF embryos to domestic cattle surrogates resulted in no pregnancies at 60 days post-transfer. This study indicates that interspecies fertilization of cattle oocytes with African buffalo epididymal sperm can occur in vitro, and that a barrier to hybridization occurs in the early stages of embryonic development. Chromosomal disparity is likely the cause of the fertilization abnormalities, abnormal development and subsequent arrest impairing the formation of hybrid embryos beyond the early morula stage. Transfer of the buffalo hybrid embryos

  15. Timing is everything for sperm assessment in fertility studies.

    PubMed

    Mariën, Dirk; Bailey, Graham P; Eichenbaum, Gary; De Jonghe, Sandra

    2016-09-01

    The fertility study design recommended in the ICH S5(R2) Harmonised Guideline for Detection of Toxicity to Reproduction for Medicinal Products emphasizes the importance of histopathological endpoints next to a pairing assessment in evaluating male fertility. However, in a male rat fertility study with JNJ-26489112, a CNS-active agent, while there were no effects on histological endpoints, mating performance or pregnancy outcomes, sperm assessment was included. The high dose males presented with reversible decreases in epididymal, but not testicular, sperm concentration and motility and an increase in abnormal sperm morphology. In view of the differences in fertility between rats and humans, these types of sperm effects in rats suggest the potential for an impact on human male fertility that would be undetected if not for the sperm assessment. Therefore, the current example suggests that including semenology as a standard endpoint in nonclinical fertility studies may be warranted. PMID:27181369

  16. Sex-Sorted Boar Sperm - An Update on Related Production Methods.

    PubMed

    Rath, D; Tiedemann, D; Gamrad, L; Johnson, L A; Klein, S; Kues, W; Mancini, R; Rehbock, C; Taylor, U; Barcikowski, S

    2015-07-01

    As in other mammals, sex sorting of pig sperm is based on quantitative flow cytometry. A major disadvantage of the technique is the relatively low efficiency to produce enough sorted sperm for artificial insemination. However, several approaches are on the way to make sexed pig sperm available for commercial application. In this context, for example, the growing field of nanotechnology may significantly contribute to these developments, as it provides highly efficient bio-nanoprobes, for example, based on plasmonic nanoparticles. Independent of the method, further development requires enormous investments and set-up of logistics to get the technology into the practical pig market. Only global players will be able to establish the necessary research projects, but in the end, a significant shift of sex ratios will be available for pig producers as it is already the case for the dairy industry. PMID:26174920

  17. Off-axis effects on the multipulse structure of sperm whale usual clicks with implications for sound production.

    PubMed

    Zimmer, Walter M X; Madsen, Peter T; Teloni, Valeria; Johnson, Mark P; Tyack, Peter L

    2005-11-01

    Sperm whales (Physeter macrocephalus) produce multipulsed clicks with their hypertrophied nasal complex. The currently accepted view of the sound generation process is based on the click structure measured directly in front of, or behind, the whale where regular interpulse intervals (IPIs) are found between successive pulses in the click. Most sperm whales, however, are recorded with the whale in an unknown orientation with respect to the hydrophone where the multipulse structure and the IPI do not conform to a regular pulse pattern. By combining far-field recordings of usual clicks with acoustic and orientation information measured by a tag on the clicking whale, we analyzed clicks from known aspects to the whale. We show that a geometric model based on the bent horn theory for sound production can explain the varying off-axis multipulse structure. Some of the sound energy that is reflected off the frontal sac radiates directly into the water creating an intermediate pulse p1/2 seen in off-axis recordings. The powerful p1 sonar pulse exits the front of the junk as predicted by the bent-horn model, showing that the junk of the sperm whale nasal complex is both anatomically and functionally homologous to the melon of smaller toothed whales. PMID:16334703

  18. Off-axis effects on the multipulse structure of sperm whale usual clicks with implications for sound production

    NASA Astrophysics Data System (ADS)

    Zimmer, Walter M. X.; Madsen, Peter T.; Teloni, Valeria; Johnson, Mark P.; Tyack, Peter L.

    2005-11-01

    Sperm whales (Physeter macrocephalus) produce multipulsed clicks with their hypertrophied nasal complex. The currently accepted view of the sound generation process is based on the click structure measured directly in front of, or behind, the whale where regular interpulse intervals (IPIs) are found between successive pulses in the click. Most sperm whales, however, are recorded with the whale in an unknown orientation with respect to the hydrophone where the multipulse structure and the IPI do not conform to a regular pulse pattern. By combining far-field recordings of usual clicks with acoustic and orientation information measured by a tag on the clicking whale, we analyzed clicks from known aspects to the whale. We show that a geometric model based on the bent horn theory for sound production can explain the varying off-axis multipulse structure. Some of the sound energy that is reflected off the frontal sac radiates directly into the water creating an intermediate pulse p1/2 seen in off-axis recordings. The powerful p1 sonar pulse exits the front of the junk as predicted by the bent-horn model, showing that the junk of the sperm whale nasal complex is both anatomically and functionally homologous to the melon of smaller toothed whales.

  19. Testis stereology, seminiferous epithelium cycle length, and daily sperm production in the ocelot (Leopardus pardalis).

    PubMed

    Silva, R C; Costa, G M J; Andrade, L M; França, L R

    2010-01-15

    Similar to most wild felids, the ocelot (Leopardus pardalis) is an endangered species. However, knowledge regarding reproductive biology of the ocelot is very limited. Germ cell transplantation is an effective technique for investigating spermatogenesis and stem cell biology in mammals, and the morphologic characterization of germ cells and knowledge of cycle length are potential tools for tracking the development of transplanted germ cells. Our goal was to investigate basic aspects related to testis structure, particularly spermatogenesis, in the ocelot. Four adult males were used. After unilateral orchiectomy, testis samples were routinely prepared for histologic, stereologic, and autoradiographic analyses. Testis weight and the gonadosomatic index were 11+/-0.6g and 0.16+/-0.01%, respectively, whereas the volume density of seminiferous tubules and Leydig cells was 83.2+/-1.6% and 9.8+/-1.5%. Based on the acrosomic system, eight stages of spermatogenesis were characterized, and germ cell morphology was very similar to that of domestic cats. Each spermatogenic cycle lasted 12.5+/-0.4 d, and the entire spermatogenic process lasted 56.3+/-1.9 d. Individual Leydig cell volume was 2522mum(3), whereas the number of Leydig and Sertoli cells per gram of testis was 38+/-5x10(6) and 46+/-3x10(6). Approximately 4.5 spermatids were found per Sertoli cell, whereas daily sperm production per gram of testis was 18.3+/-1x10(6), slightly higher than values reported for other felids. The knowledge obtained in this study could be very useful to the preservation of the ocelot using domestic cat testes to generate and propagate the ocelot genome. PMID:19853903

  20. Laser radiation and motility patterns of human sperm

    SciTech Connect

    Lenzi, A.; Claroni, F.; Gandini, L.; Lombardo, F.; Barbieri, C.; Lino, A.; Dondero, F. )

    1989-01-01

    Human sperm were exposed in vitro to laser radiation. An increase in progressive sperm motility was associated with a faster rate of sperm ATP consumption. Computer-assisted analysis of sperm motility confirmed the positive effect of laser irradiation on velocity and linearity of sperm.

  1. Effects of intratesticular zinc gluconate treatment on testicular dimensions, echodensity, histology, sperm production, and testosterone secretion in American black bears (Ursus americanus).

    PubMed

    Brito, Leonardo F C; Sertich, Patricia L; Rives, William; Knobbe, Marc; Del Piero, Fabio; Stull, Gordon B

    2011-05-01

    Eight adult American black bears were used to evaluate the effects of chemical castration by intratesticular zinc gluconate treatment on testicular dimensions, echodensity, histology, sperm production, and testosterone secretion. Treatment did not affect testicular dimensions and did not result in decreased resting or GnRH-stimulated testosterone secretion. Multifocal hyperchoic areas in the testicular parenchyma were observed on ultrasound examination, and white foci were observed on gross pathology examination after zinc gluconate treatment. Histologically, there were normal seminiferous tubules containing either round or elongated spermatids, along with abnormal tubules in all bears after treatment. Vacuolation of the seminiferous epithelium, sloughing of germ cells into the tubules' lumen, presence of multinuclear giant cells, and reduced height of the seminiferous epithelium with missing generations of germ cells were commonly observed. The most severe testicular changes were multifocal and included fibrosis, complete degeneration of the seminiferous epithelium with shrinkage of the tubule, and sperm stasis. Epididymal sperm reserve was 982.74 ± 654.16 × 10(6) sperm (mean ± SEM) and motile sperm were observed in the epididymis of all but one of the bears. In conclusion, although intratesticular zinc gluconate treatment in black bears resulted in testicular degenerative changes detected by ultrasound and histology examinations, sperm production was not completely ablated. We inferred that normal fertility might have been compromised, but treatment unlikely resulted in sterility. PMID:21356548

  2. In vitro production of haploid sperm cells from male germ cells of foetal cattle.

    PubMed

    Dong, Wu-Zi; Hua, Jin-Lian; Shen, Wen-Zheng; Dou, Zhong-Ying

    2010-04-01

    The purpose of this study was to isolate the foetal cattle male germ cells (mGCs) and then induce them into sperm cells. The mGCs were purified and enriched by a two-step plating method based on the different adherence velocities of mGCs and somatic cells. The percentage of the vasa and the c-kit positive cells were 95.34+/-2.25% and 53.3+/-1.03% by using flow cytometry analysis (FCA), respectively. In feeder-free culture system, the half-suspending cells appeared and formed a 16-cell rosary in medium after the mGCs were cultured for 6-8 days. On immunocytochemical staining during the second passage, some single cells adhering to the plate appeared to be both Oct-4 and alpha6-integrin positive. During the third passage, the mGCs were induced for 48 h by retinol acid (RA) on Sertoli cell-feeder layer, followed by 5-7 days culture in an RA-free medium. Some elongated sperm-like cells appeared in the medium at this stage. We found that the most effective concentration of RA for the inducement was 10(-7)moll(-1) (P<0.01). The haploid cells in suspension were identified by FCA. The elongated sperm-like cells showed proacrosome-like structure and the flagellum with fibre construct under electron microscopy. The mRNA of outer dense fibre-3 (ODF-3) and transcription protein-1 (TP-1) could be detected in the suspended cells by using reverse transcription polymerase chain reaction (RT-PCR). About 23.1% bovine oocytes could be activated to perform cleavage by intracytoplasmic injection with the sperm-like cells, but embryos did not further develop. Our investigation further demonstrated that foetal cattle mGCs could be induced in vitro into haploid sperm in the short term. PMID:19632794

  3. In boar sperm capacitation L-lactate and succinate, but not pyruvate and citrate, contribute to the mitochondrial membrane potential increase as monitored via safranine O fluorescence.

    PubMed

    Paventi, Gianluca; Lessard, Christian; Bailey, Janice L; Passarella, Salvatore

    2015-07-01

    Having ascertained using JC-1 as a probe that, in distinction with the controls, during capacitation boar sperm maintains high mitochondrial membrane potential (ΔΨ), to gain some insight into the role of mitochondria in capacitation, we monitored ΔΨ generation due to externally added metabolites either in hypotonically-treated spermatozoa (HTS) or in intact cells by using safranine O as a probe. During capacitation, the addition to HTS of L-lactate and succinate but not those of pyruvate, citrate and ascorbate + TMPD resulted in increase of ΔΨ generation. Accordingly, the addition of L-lactate and succinate, but not that of citrate, to intact sperm resulted in ΔΨ generation increased in capacitation. PMID:25956060

  4. No evidence of trade-offs in the evolution of sperm numbers and sperm size in mammals.

    PubMed

    Tourmente, M; Delbarco Trillo, J; Roldan, E R S

    2015-10-01

    Post-copulatory sexual selection, in the form sperm competition, has influenced the evolution of several male reproductive traits. However, theory predicts that sperm competition would lead to trade-offs between numbers and size of spermatozoa because increased costs per cell would result in a reduction of sperm number if both traits share the same energetic budget. Theoretical models have proposed that, in large animals, increased sperm size would have minimal fitness advantage compared with increased sperm numbers. Thus, sperm numbers would evolve more rapidly than sperm size under sperm competition pressure. We tested in mammals whether sperm competition maximizes sperm numbers and size, and whether there is a trade-off between these traits. Our results showed that sperm competition maximizes sperm numbers in eutherian and metatherian mammals. There was no evidence of a trade-off between sperm numbers and sperm size in any of the two mammalian clades as we did not observe any significant relationship between sperm numbers and sperm size once the effect of sperm competition was taken into account. Maximization of both numbers and size in mammals may occur because each trait is crucial at different stages in sperm's life; for example size-determined sperm velocity is a key determinant of fertilization success. In addition, numbers and size may also be influenced by diverse energetic budgets required at different stages of sperm formation. PMID:26190170

  5. Sperm preparation for ART

    PubMed Central

    Henkel, Ralf R; Schill, Wolf-Bernhard

    2003-01-01

    The onset of clinical assisted reproduction, a quarter of a century ago, required the isolation of motile spermatozoa. As the indication of assisted reproduction shifted from mere gynaecological indications to andrological indications during the years, this urged andrological research to understand the physiology of male germ cell better and develop more sophisticated techniques to separate functional spermatozoa from those that are immotile, have poor morphology or are not capable to fertilize oocytes. Initially, starting from simple washing of spermatozoa, separation techniques, based on different principles like migration, filtration or density gradient centrifugation evolved. The most simple and cheapest is the conventional swim-up procedure. A more sophisticated and most gentle migration method is migration-sedimentation. However, its yield is relatively small and the technique is therefore normally only limited to ejaculates with a high number of motile spermatozoa. Recently, however, the method was also successfully used to isolate spermatozoa for intracytoplasmic sperm injection (ICSI). Sperm separation methods that yield a higher number of motile spermatozoa are glass wool filtration or density gradient centrifugation with different media. Since Percoll® as a density medium was removed from the market in 1996 for clinical use in the human because of its risk of contamination with endotoxins, other media like IxaPrep®, Nycodenz, SilSelect®, PureSperm® or Isolate® were developed in order to replace Percoll®. Today, an array of different methods is available and the selection depends on the quality of the ejaculates, which also includes production of reactive oxygen species (ROS) by spermatozoa and leukocytes. Ejaculates with ROS production should not be separated by means of conventional swim-up, as this can severely damage the spermatozoa. In order to protect the male germ cells from the influence of ROS and to stimulate their motility to increase the

  6. Sperm Cells Induce Distinct Cytokine Response in Peripheral Mononuclear Cells from Infertile Women with Serum Anti-Sperm Antibodies

    PubMed Central

    Kverka, Miloslav; Ulcova-Gallova, Zdenka; Bartova, Jirina; Cibulka, Jan; Bibkova, Katarina; Micanova, Zdenka; Tlaskalova-Hogenova, Helena

    2012-01-01

    Background and Aims Anti-sperm antibodies in can markedly reduce the likelihood of natural conception. The etiology of this anti-sperm immunity in human females is unknown. We compared the cytokine response of peripheral blood mononuclear cells (PBMCs) from infertile patients with or without anti-sperm antibodies (ASA) and fertile women. Methodology/Principal Findings We cultivated the PBMCs together with sperm antigens (whole cells or cell lysate), and screened the supernatants for 40 cytokines by antibody array. When stimulated with whole sperm cells, the PBMCs from patients with ASA produce less IL-3, IL-11, IL-13, ICAM-1, GCSF and more IL-2, IL-4 and IL-12p70 as compared to healthy women. PBMCs from patients with ASA produce typically less IL-13, IL-7, IL-17 and MIG, and more MIP-1β and IL-8, as compared to PBMCs from patients without ASA. In response to sperm cell lysate, PBMCs from infertile women without ASA respond initially by increase in production of growth factors (GCSF, GM-CSF and PDGF-BB) followed by increase in chemokines (e.g. IL-8, MCP-1 and MIP-1β). Conclusions Cellular immune responses to sperm antigens, measured by production of cytokines, differ among infertile women with ASA, infertile women without ASA and healthy women. This difference could play an important role in the initial steps of the infertility pathogenesis. PMID:22952917

  7. Variability in sperm form and function in the context of sperm competition risk in two Tupinambis lizards

    PubMed Central

    Blengini, Cecilia S; Sergio, Naretto; Gabriela, Cardozo; Giojalas, Laura C; Margarita, Chiaraviglio

    2014-01-01

    In polyandrous species, sperm morphometry and sperm velocity are under strong sexual selection. Although several hypotheses have been proposed to explain the role of sperm competition in sperm trait variation, this aspect is still poorly understood. It has been suggested that an increase in sperm competition pressure could reduce sperm size variation or produce a diversity of sperm to maximize male fertilization success. We aim at elucidating the variability of sperm morphometric traits and velocity in two Tupinambis lizards in the context of sperm competition risk. Sperm traits showed substantial variation at all levels examined: between species, among males within species, and within the ejaculate of individual males. Sperm velocity was found to be positively correlated with flagellum: midpiece ratio, with relatively longer flagella associated with faster sperm. Our results document high variability in sperm form and function in lizards. PMID:25505535

  8. Variability in sperm form and function in the context of sperm competition risk in two Tupinambis lizards.

    PubMed

    Blengini, Cecilia S; Sergio, Naretto; Gabriela, Cardozo; Giojalas, Laura C; Margarita, Chiaraviglio

    2014-11-01

    In polyandrous species, sperm morphometry and sperm velocity are under strong sexual selection. Although several hypotheses have been proposed to explain the role of sperm competition in sperm trait variation, this aspect is still poorly understood. It has been suggested that an increase in sperm competition pressure could reduce sperm size variation or produce a diversity of sperm to maximize male fertilization success. We aim at elucidating the variability of sperm morphometric traits and velocity in two Tupinambis lizards in the context of sperm competition risk. Sperm traits showed substantial variation at all levels examined: between species, among males within species, and within the ejaculate of individual males. Sperm velocity was found to be positively correlated with flagellum: midpiece ratio, with relatively longer flagella associated with faster sperm. Our results document high variability in sperm form and function in lizards. PMID:25505535

  9. An Extract of Pomegranate Fruit and Galangal Rhizome Increases the Numbers of Motile Sperm: A Prospective, Randomised, Controlled, Double-Blinded Trial

    PubMed Central

    Fedder, Maja D. K.; Jakobsen, Henrik B.; Giversen, Ina; Christensen, Lars P.; Parner, Erik T.; Fedder, Jens

    2014-01-01

    Pomegranate fruit (Punica granatum) and galangal (Alpinia galanga) have separately been shown to stimulate spermatogenesis and to increase sperm counts and motility in rodents. Within traditional medicine, pomegranate fruit has long been used to increase fertility, however studies on the effect on spermatogenesis in humans have never been published. With this study we investigated whether oral intake of tablets containing standardised amounts of extract of pomegranate fruit and powder of greater galangal rhizome (Punalpin) would increase the total number of motile spermatozoa. The study was designed as a prospective, randomized, controlled, double-blinded trial. Enrolment was based on the mean total number of motile spermatozoa of two ejaculates. The participants delivered an ejaculate after 4–8 days of tablet intake and two ejaculates just before they stopped taking the tablets. Seventy adult men with a semen quality not meeting the standards for commercial application at Nordic Cryobank, but without azoospermia, were included in the study. Participants were randomized to take tablets containing extract of pomegranate fruit (standardised with respect to punicalagin A+B, punicalin and ellagic acid) and freeze-dried rhizome of greater galangal (standardised with respect to 1′S-1′-acetoxychavicol acetate) or placebo on a daily basis for three months. Sixty-six participants completed the intervention (active treatment: n = 34; placebo: n = 32). After the intervention the total number of motile spermatozoa was increased in participants treated with plant extracts compared with the placebo group (p = 0.026). After three months of active treatment, the average total number of motile sperm increased by 62% (from 23.4 to 37.8 millions), while for the placebo group, the number of motile sperm increased by 20%. Sperm morphology was not affected by the treatment. Our findings may help subfertile men to gain an improved amount of motile ejaculated sperm by

  10. The effects of four insect growth-regulating (IGR) insecticides on honeybee (Apis mellifera L.) colony development, queen rearing and drone sperm production.

    PubMed

    Thompson, Helen M; Wilkins, Selwyn; Battersby, Alastair H; Waite, Ruth J; Wilkinson, David

    2005-10-01

    This study assessed the effects of exposure to IGRs on the long-term development of the honeybee colony, viability of queens and sperm production in drones and integrated the data into a honeybee population model. Colonies treated with diflubenzuron resulted in a short-term reduction in the numbers of adult bees and brood. Colonies treated with fenoxycarb declined during the season earlier and started the season slower. The number of queens that successfully mated and laid eggs was affected in the fenoxycarb treatment group but there were no significant differences in the drone sperm counts between the colonies. An existing honeybee population model was modified to include exposure to IGRs. In the model, fenoxycarb reduced the winter size of the colony, with the greatest effects following a June or an August application. Assuming a 'larvae per nurse bee' ratio of 1.5 for brood rearing capability, the reduction in winter size of a colony following a fenoxycarb application was at its worst about 8%. However, even if only those bees reared within 2 weeks of the IGR being applied are subject to premature ageing, this might significantly reduce the size of over-wintering colonies, and increase the chance of the bee population dwindling and dying in late winter or early spring. PMID:16160749

  11. Diploid males, diploid sperm production, and triploid females in the ant Tapinoma erraticum

    NASA Astrophysics Data System (ADS)

    Cournault, Laurent; Aron, Serge

    2009-12-01

    Under complementary sex determination (CSD), females of Hymenoptera arise from diploid, fertilized eggs and males from haploid, unfertilized eggs. Incidentally, fertilized eggs that inherit two identical alleles at the CSD locus will develop into diploid males. Diploid males are usually unviable or sterile. In a few species, however, they produce diploid sperm and father a triploid female progeny. Diploid males have been reported in a number of social Hymenoptera, but the occurrence of triploid females has hardly ever been documented. Here, we report the presence of triploid females, diploid males, and diploid sperm (produced by diploid males and stored in queen spermathecae) in the ant Tapinoma erraticum. Moreover, we show variations in the frequency of triploids among female castes: Triploid females are more frequent among workers than virgin queens; they are absent among mated, reproductive queens. The frequency of triploid workers also varies between populations and between nests within populations.

  12. Sperm studies in anesthesiologists

    SciTech Connect

    Wyrobek, A.J.; Brodsky, J.; Gordon, l.; Moore, D.H., II; Watchmaker, G.; Cohen, E.N.

    1981-11-01

    Semen samples were collected from 46 anesthesiologists each of whom had worked a minimum of one year in hospital operating rooms ventilated with modern gas-scavenging devices. Samples collected from 26 beginning residents in anesthesiology served as controls. Concentrations of sperm and percentage of sperm having abnormal head shapes were determined for each sample. No significant differences were found between anesthesiologists and beginning residents. Limiting the analyses to men having no confounding factors (varicocele, recent illness, medications, heavy smoking, frequent sauna use) did not change the results. The sperm concentration and morphology in 13 men did not change signficantly after one year of exposure to anesthetic gases. However, the group of men who had one or more confounding factors (excluding exposure to anesthetic gases) showed significantly higher percentages of sperm abnormalities than did the group of men without such factors. These results suggest that limited exposure to anesthetic gases does not significantly affect sperm production as judged by changes in sperm concentration and morphology. These data are reassuring, but since the hospitals surveyed used modern gas-scavenging devices, men who are occupationally exposed to anesthetic gases without this protection should be studied for fuller assessment of the possible human spermatotoxic effects.

  13. Lipids and calcium uptake of sperm in relation to cold shock and preservation: a review.

    PubMed

    White, I G

    1993-01-01

    When sperm of the ram, bull, boar and stallion are cold-shocked by rapid cooling to near freezing point, motility and metabolic activity are irreversibly depressed and the acrosome and plasma membrane disrupted. Ram sperm become susceptible to cold shock in the proximal corpus region of the epididymis when the cytoplasmic droplet has moved backwards to the distal portion of the sperm midpiece. The membrane constituents phospholipids and cholesterol are important in cold shock which causes loss of lipid from sperm. The susceptibility of sperm to cold shock is linked with a high ratio of unsaturated:saturated fatty acids in the phospholipids and a low cholesterol content. The high unsaturated fatty acid content of sperm also makes them susceptible to damage from peroxidation which adversely affects motility, metabolism, ultrastructure and fertility. Hydroxynonenal, a product of fatty acid peroxidation, depresses the motility and oxygen uptake of ram sperm in vitro and may react with the -SH groups of the axonemal microtubules. High calcium concentrations in the external medium may decrease the motility and metabolism of sperm and 'calcium intoxication' may be a factor in cold shock. Lowering the environmental temperature increases calcium uptake by sperm and the effect is aggravated if the rate of cooling is rapid. Phospholipids, particularly those in egg yolk, protect sperm to some extent from cold shock and also prevent increased calcium flux into the sperm. Suggestions are made for increasing the life span of sperm during preservation and microencapsulation by adding agents that may stabilize membranes, counter peroxidation and decrease calcium uptake. PMID:9627725

  14. Leydig cell number and sperm production decrease induced by chronic ametryn exposure: a negative impact on animal reproductive health.

    PubMed

    Dantas, T A; Cancian, G; Neodini, D N R; Mano, D R S; Capucho, C; Predes, F S; Pulz, R Barbieri; Pigoso, A A; Dolder, H; Severi-Aguiar, G D C

    2015-06-01

    Ametryn is an herbicide used to control broadleaf and grass weeds and its acute and chronic toxicity is expected to be low. Since toxicological data on ametryn is scarce, the aim of this study was to evaluate rat reproductive toxicity. Thirty-six adult male Wistar rats (90 days) were divided into three groups: Co (control) and T1 and T2 exposed to 15 and 30 mg/kg/day of ametryn, respectively, for 56 days. Testicular analysis demonstrated that ametryn decreased sperm number per testis, daily sperm production, and Leydig cell number in both treated groups, although little perceptible morphological change has been observed in seminiferous tubule structure. Lipid peroxidation was higher in group T2, catalase activity decreased in T1 group, superoxide dismutase activity diminished, and a smaller number of sulphydryl groups of total proteins were verified in both exposed groups, suggesting oxidative stress. These results showed negative ametryn influence on the testes and can compromise animal reproductive performance and survival. PMID:25561257

  15. Effect of Astaxanthin on Human Sperm Capacitation

    PubMed Central

    Donà, Gabriella; Kožuh, Ivana; Brunati, Anna Maria; Andrisani, Alessandra; Ambrosini, Guido; Bonanni, Guglielmo; Ragazzi, Eugenio; Armanini, Decio; Clari, Giulio; Bordin, Luciana

    2013-01-01

    In order to be able to fertilize oocytes, human sperm must undergo a series of morphological and structural alterations, known as capacitation. It has been shown that the production of endogenous sperm reactive oxygen species (ROS) plays a key role in causing cells to undergo a massive acrosome reaction (AR). Astaxanthin (Asta), a photo-protective red pigment belonging to the carotenoid family, is recognized as having anti-oxidant, anti-cancer, anti-diabetic and anti-inflammatory properties and is present in many dietary supplements. This study evaluates the effect of Asta in a capacitating buffer which induces low ROS production and low percentages of acrosome-reacted cells (ARC). Sperm cells were incubated in the presence or absence of increasing concentrations of Asta or diamide (Diam) and analyzed for their ROS production, Tyr-phosphorylation (Tyr-P) pattern and percentages of ARC and non-viable cells (NVC). Results show that Asta ameliorated both sperm head Tyr-P and ARC values without affecting the ROS generation curve, whereas Diam succeeded in enhancing the Tyr-P level but only of the flagellum without increasing ARC values. It is suggested that Asta can be inserted in the membrane and therefore create capacitation-like membrane alteration which allow Tyr-P of the head. Once this has occurred, AR can take place and involves a higher numbers of cells. PMID:23736766

  16. Effect of astaxanthin on human sperm capacitation.

    PubMed

    Donà, Gabriella; Kožuh, Ivana; Brunati, Anna Maria; Andrisani, Alessandra; Ambrosini, Guido; Bonanni, Guglielmo; Ragazzi, Eugenio; Armanini, Decio; Clari, Giulio; Bordin, Luciana

    2013-06-01

    In order to be able to fertilize oocytes, human sperm must undergo a series of morphological and structural alterations, known as capacitation. It has been shown that the production of endogenous sperm reactive oxygen species (ROS) plays a key role in causing cells to undergo a massive acrosome reaction (AR). Astaxanthin (Asta), a photo-protective red pigment belonging to the carotenoid family, is recognized as having anti-oxidant, anti-cancer, anti-diabetic and anti-inflammatory properties and is present in many dietary supplements. This study evaluates the effect of Asta in a capacitating buffer which induces low ROS production and low percentages of acrosome-reacted cells (ARC). Sperm cells were incubated in the presence or absence of increasing concentrations of Asta or diamide (Diam) and analyzed for their ROS production, Tyr-phosphorylation (Tyr-P) pattern and percentages of ARC and non-viable cells (NVC). Results show that Asta ameliorated both sperm head Tyr-P and ARC values without affecting the ROS generation curve, whereas Diam succeeded in enhancing the Tyr-P level but only of the flagellum without increasing ARC values. It is suggested that Asta can be inserted in the membrane and therefore create capacitation-like membrane alteration which allow Tyr-P of the head. Once this has occurred, AR can take place and involves a higher numbers of cells. PMID:23736766

  17. Sperm storage in caecilian amphibians

    PubMed Central

    2012-01-01

    Background Female sperm storage has evolved independently multiple times among vertebrates to control reproduction in response to the environment. In internally fertilising amphibians, female salamanders store sperm in cloacal spermathecae, whereas among anurans sperm storage in oviducts is known only in tailed frogs. Facilitated through extensive field sampling following historical observations we tested for sperm storing structures in the female urogenital tract of fossorial, tropical caecilian amphibians. Findings In the oviparous Ichthyophis cf. kohtaoensis, aggregated sperm were present in a distinct region of the posterior oviduct but not in the cloaca in six out of seven vitellogenic females prior to oviposition. Spermatozoa were found most abundantly between the mucosal folds. In relation to the reproductive status decreased amounts of sperm were present in gravid females compared to pre-ovulatory females. Sperm were absent in females past oviposition. Conclusions Our findings indicate short-term oviductal sperm storage in the oviparous Ichthyophis cf. kohtaoensis. We assume that in female caecilians exhibiting high levels of parental investment sperm storage has evolved in order to optimally coordinate reproductive events and to increase fitness. PMID:22672478

  18. No evidence for sperm priming responses under varying sperm competition risk or intensity in guppies

    NASA Astrophysics Data System (ADS)

    Evans, Jonathan P.

    2009-07-01

    Sperm competition theory predicts that males should tailor their investment in ejaculates according to the number of rival males competing to fertilize a female’s eggs. Research spanning several taxa supports this prediction by showing that males are often sensitive to the level of sperm competition and adjust their investment in sperm numbers accordingly. More recent work has revealed that males may also tailor the quality of sperm according to the number of males competing for fertilization. Here I test for both effects in guppies ( Poecilia reticulata) in an experiment that simultaneously evaluates the risk and intensity models of sperm competition. The experiment determined whether male guppies adjust the number (stripped ejaculate size) and quality (sperm velocity and viability) of sperm that are primed over a 3-day period according to experimental changes in the perceived level of sperm competition. A total of 136 focal males were initially stripped of all retrievable sperm and assayed for these sperm traits before being allocated at random to one of four treatments simulating different levels of sperm competition risk and intensity. During the 3-day treatment phase, focal males had visual and olfactory access to a sexually receptive (initially virgin) female maintained with different numbers of stimulus males to simulate variation in the risk and intensity of sperm competition. Following this, males were assayed again for the sperm traits. Contrary to predictions, there was no significant change in any of the measured variables among treatments, although qualitatively the patterns for sperm velocity and viability did conform to expectation. The lack of any trend for the number of sperm primed was unequivocal and future work examining the effects of sperm competition on sperm production should focus on whether males differentially allocate sperm numbers among matings that differ in the level of sperm competition.

  19. Responses of testis, epididymis, and sperm of pubertal rats exposed to functionalized multiwalled carbon nanotubes.

    PubMed

    Farombi, Ebenezer O; Adedara, Isaac A; Forcados, Gilead E; Anao, Osemudiamen O; Agbowo, Agatha; Patlolla, Anita K

    2016-05-01

    The present study investigated the response of testes, epididymides and sperm in pubertal Wistar rats following exposure to 0, 0.25, 0.5, 0.75, and 1.0 mg kg(-1) functionalized multi-walled carbon nanotubes (f-MWCNTs) for 5 days. The results showed that administration of (f-MWCNTs) significantly increased the activities of superoxide dismutase, catalase, and glutathione peroxidase in a dose-dependent manner in both testes and sperm compared with control group. Moreover, the significant decrease in the activity of glutathione-S-transferase and glutathione level was accompanied with significant elevation in the levels of hydrogen peroxide and malondialdehyde in both testes and sperm of (f-MWCNTs)-treated rats. The spermiogram of (f-MWCNTs)-treated rats indicated significant decrease in epididymal sperm number, sperm progressive motility, testicular sperm number and daily sperm production with elevated sperm abnormalities when compared with the control. Exposure to (f-MWCNTs) decreased plasma testosterone level and produced marked morphological changes including decreased geminal epithelium, edema, congestion, reduced spermatogenic cells and focal areas of tubular degeneration in the testes. The lumen of the epididymides contained reduced sperm cells and there was mild to severe hyperplasia epithelial cells lining the duct of the epididymis. Collectively, pubertal exposure of male rats to (f-MWCNTs) elicited oxidative stress response resulting in marked testicular and epididymides dysfunction. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 543-551, 2016. PMID:25410135

  20. The adverse effects of low-dose exposure to Di(2-ethylhexyl) phthalate during adolescence on sperm function in adult rats.

    PubMed

    Hsu, Ping-Chi; Kuo, Ya-Ting; Leon Guo, Yueliang; Chen, Jenq-Renn; Tsai, Shinn-Shyong; Chao, How-Ran; Teng, Yen-Ni; Pan, Min-Hsiung

    2016-06-01

    Di(2-ethylhexyl) phthalate (DEHP) is the most crucial phthalate derivative added to polyvinyl chloride as a plasticizer. This study examined the effects of low-dose exposure to DEHP during adolescence on sperm function in adult rats. The male rats were daily gavaged with 30, 100, 300, and 1000 µg kg(-1) of DEHP or corn oil from postnatal day (PND) 42 until PND 105. The selection of DEHP doses ranged from the mean daily intake by the normal-population exposure levels to no-observed-adverse-effect level of DEHP for the endpoints evaluated until adulthood. Significant increases in the percentage of sperm with tail abnormality, tendency for sperm DNA fragmentation index (DFI) and percentage of sperm with DFI were found in those exposed to 100, 300, and 1000 µg kg(-1) (P < 0.05). We observed a significant increase of hydrogen peroxide (H2 O2 ) generation in the sperm of the 1000 µg kg(-1) group compared with the control group (P < 0.05). The excessive production of sperm H2 O2 coincided with an increase in sperm DFI. In this study, the lowest-observed-adverse-effect level for sperm toxicity was considered to be 100 µg DEHP/kg/day in sperm morphology and chromatin DNA damage. Further research is necessary to clarify the mechanisms of DEHP-related sperm ROS generation on sperm DNA damage. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 706-712, 2016. PMID:25410017

  1. Decoding mechanisms of loss of fertilization ability of cryopreserved mouse sperm

    NASA Astrophysics Data System (ADS)

    Gray, Jeffrey Earl

    Cryopreservation of mouse sperm is an important technology for management of biomedical research resources. Dramatic progress has been made recently in the development of protocols that combat mouse-strain specific reduction of IVF after cryopreservation. Equal emphasis, however, has not been placed on investigating the biological mechanisms underlying these improvements to IVF. This dissertation broadly investigates the basic question of how mouse-strain specific reduction of IVF occurs after cryopreservation, and how recently developed protocols prevent this process. My research investigated the effects of antioxidants, the cholesterol-acceptor CD, reduced calcium media, and TYH capacitation media on sperm function and oxidative stress after cryopreservation in a variety of mouse strains. I found that reduced IVF was associated with loss of capacitation-dependent sperm function in three strains, B6/J, B6/N, and 129X1, and CD improved sperm function and IVF in all three strains. These findings suggest that cryopreservation inhibits cholesterol efflux resulting in reduced IVF of many mouse strains. I also found that cryopreservation induces uniquely high production of mitochondrial H2O2 by B6/J sperm. H2O2 present in other cellular compartments of B6/J sperm was not elevated compared to other strains. High levels of mitochondrial H2O2 were associated with lipid peroxidation of the sperm head and inability to acrosome react. Antioxidants reduced mitochondrial H2O2 production, decreased sperm head lipid peroxidation, and improved acrosome reaction. The cryopreservation-induced increase in mitochondrial H2O2 production of B6/J and B6129XF1 sperm was associated with elevation of intracellular calcium after cryopreservation and dependent on mitochondrial metabolic substrates. Reducing intracellular calcium levels or removing mitochondrial metabolic substrates decreased mitochondrial H2O2 production and increased IVF rates of cryopreserved B6/J sperm. Many of the strains

  2. Fires increase Amazon forest productivity through increases in diffuse radiation

    NASA Astrophysics Data System (ADS)

    Rap, A.; Spracklen, D. V.; Mercado, L.; Reddington, C. L.; Haywood, J. M.; Ellis, R. J.; Phillips, O. L.; Artaxo, P.; Bonal, D.; Restrepo Coupe, N.; Butt, N.

    2015-06-01

    Atmospheric aerosol scatters solar radiation increasing the fraction of diffuse radiation and the efficiency of photosynthesis. We quantify the impacts of biomass burning aerosol (BBA) on diffuse radiation and plant photosynthesis across Amazonia during 1998-2007. Evaluation against observed aerosol optical depth allows us to provide lower and upper BBA emissions estimates. BBA increases Amazon basin annual mean diffuse radiation by 3.4-6.8% and net primary production (NPP) by 1.4-2.8%, with quoted ranges driven by uncertainty in BBA emissions. The enhancement of Amazon basin NPP by 78-156 Tg C a-1 is equivalent to 33-65% of the annual regional carbon emissions from biomass burning. This NPP increase occurs during the dry season and acts to counteract some of the observed effect of drought on tropical production. We estimate that 30-60 Tg C a-1 of this NPP enhancement is within woody tissue, accounting for 8-16% of the observed carbon sink across mature Amazonian forests.

  3. Reactive oxygen species and boar sperm function.

    PubMed

    Awda, Basim J; Mackenzie-Bell, Meghan; Buhr, Mary M

    2009-09-01

    Boar spermatozoa are very susceptible to reactive oxygen species (ROS), but ROS involvement in damage and/or capacitation is unclear. The impact of exposing fresh boar spermatozoa to an ROS-generating system (xanthine/xanthine oxidase; XA/XO) on sperm ROS content, membrane lipid peroxidation, phospholipase (PL) A activity, and motility, viability, and capacitation was contrasted to ROS content and sperm function after cryopreservation. Exposing boar sperm (n = 4-5 ejaculates) to the ROS-generating system for 30 min rapidly increased hydrogen peroxide (H2O2) and lipid peroxidation in all sperm, increased PLA in dead sperm, and did not affect intracellular O2- (flow cytometry of sperm labeled with 2',7'-dichlorodihydrofluorscein diacetate, BODIPY 581/591 C11, bis-BODIPY-FL C11, hydroethidine, respectively; counterstained for viability). Sperm viability remained high, but sperm became immotile. Cryopreservation decreased sperm motility, viability, and intracellular O2- significantly, but did not affect H2O2. As expected, more sperm incubated in capacitating media than Beltsville thawing solution buffer underwent acrosome reactions and protein tyrosine phosphorylation (four proteins, 58-174 kDa); which proteins were tyrosine phosphorylated was pH dependent. Pre-exposing sperm to the ROS-generating system increased the percentage of sperm that underwent acrosome reactions after incubation in capacitating conditions (P < 0.025), and decreased capacitation-dependent increases in two tyrosine-phosphorylated proteins (P < or = 0.035). In summary, H2O2 is the major free radical mediating direct ROS effects, but not cryopreservation changes, on boar sperm. Boar sperm motility, acrosome integrity, and lipid peroxidation are more sensitive indicators of oxidative stress than viability and PLA activity. ROS may stimulate the acrosome reaction in boar sperm through membrane lipid peroxidation and PLA activation. PMID:19357363

  4. Hyaluronic acid (Sperm Select) improves retention of sperm motility and velocity in normospermic and oligospermic specimens.

    PubMed

    Huszar, G; Willetts, M; Corrales, M

    1990-12-01

    The effects of Sperm Select (Pharmacia AB, Uppsala, Sweden), a hyaluronic acid medium, on the motility and membrane integrity properties of sperm were studied. In 15 normospermic specimens after overnight incubation, the motility parameters in the control versus the Sperm Select group were as follows (mean +/- SEM): motility, 18.8% +/- 2.8% versus 27.4% +/- 2.9%; velocity, 21.5 +/- 2.4 versus 27.2 +/- 2.2 microns/s; linearity, 3.8 +/- 0.3 versus 4.4 +/- 0.2; lateral head displacement, 1.5 +/- 0.2 versus 1.9 +/- 0.1 microns; and tail beat/cross frequency, 8.8 +/- 1.3 versus 10.8 +/- 1.4 Hz. The density of motile sperm was 10.8 +/- 2.3 versus 18.5 +/- 2.5 X 10(6) sperm/mL. Finally, the velocity coefficient, the multiple of the sperm motility and linear velocity, was 4.6 +/- 1.1 versus 8.1 +/- 1.4. However, we found no Sperm Select related differences when testing sperm membrane integrity with hypoosmotic swelling and supravital staining. Thus, Sperm Select improves the retention of sperm motility (most prominently velocity) apparently due to a direct action of hyaluronic acid on sperm metabolism or contractility rather than to preservation of sperm membrane integrity. In 20 oligospermic specimens, Sperm Select caused similar improvements in sperm motility, and the duration of motility could be predicted from the degree of enhancement in sperm velocity after short-term Sperm Select exposure. A modified Sperm Select protocol is described that further increases motile sperm yield without a centrifugation step. PMID:1700958

  5. Similar time restriction for intracytoplasmic sperm injection and round spermatid injection into activated oocytes for efficient offspring production.

    PubMed

    Kishigami, Satoshi; Wakayama, Sayaka; Nguyen, Van Thuan; Wakayama, Teruhiko

    2004-06-01

    The injection of male haploid germ cells, such as spermatozoa and round spermatids, into preactivated mouse oocytes can result in the development of viable embryos and offspring. However, it is not clear how the timing of intracytoplasmic sperm injection (ICSI) and round spermatid injection (ROSI) affects the production of offspring. We carried out ICSI and ROSI every 20 min for up to 4 h after the activation of mouse oocytes by Sr(2+) and compared the late-stage development of ICSI- and ROSI- treated oocytes, including the formation of pronuclei, blastocyst formation, and offspring production. The rate of pronucleus formation (RPF) after carrying out ICSI started to decrease from >95% at 100 min following oocyte activation and declined to <20% by 180 min. In comparison, RPF by ROSI decreased gradually from >70% between 0 and 4 h after activation. The RPFs were closely correlated with blastocyst formation. Offspring production for both ICSI and ROSI decreased significantly when injections were conducted after 100 min, a time at which activated oocytes were in the early G1 stage of the cell cycle. These results suggest that spermatozoa and round spermatids have different potentials for inducing the formation of a male pronucleus in activated oocytes, but ICSI and ROSI are both subject to the same time constraint for the efficient production of offspring, which is determined by the cell cycle of the activated oocyte. PMID:14985245

  6. Drosophila sperm motility in the reproductive tract.

    PubMed

    Yang, Yong; Lu, Xiangyi

    2011-05-01

    Motile cilia and flagella exhibit many waveforms as outputs of dynein activation sequences on the highly conserved axoneme. Motility change of sperm in the reproductive tract is difficult to study and remains an important area of investigation. Sperm typically execute a sinusoidal waveform. Increased viscosity in the medium induces somewhat unusual arc-line and helical waveforms in some sperm. However, whether the latter two waveforms occur in vivo is not known. Using green fluorescence protein imaging, we show that Drosophila sperm in the uterus move in circular foci via arc-line waves, predominantly in a tail-leading orientation. From the uterus, a small fraction of the sperm enters the seminal receptacle (SR) in parallel formations. After sperm storage and coincident with fertilization of the egg, the sperm exit the SR via head-leading helical waves. Consistent with the observed bidirectional movements, the sperm show the ability to propagate both base-to-tip and tip-to-base flagellar waves. Numerous studies have shown that sperm motility is regulated by intraflagellar calcium concentrations; in particular, the Pkd2 calcium channel has been shown to affect sperm storage. Our analyses here suggest that Pkd2 is required for the sperm to adopt the correct waveform and movement orientation during SR entry. A working model for the sperm's SR entry movement is proposed. PMID:21293028

  7. Transcript levels of the soluble sperm factor protein phospholipase C zeta 1 (PLCζ1) increase through induced spermatogenesis in European eel.

    PubMed

    Morini, Marina; Peñaranda, David S; Vílchez, María C; Gallego, Víctor; Nourizadeh-Lillabadi, Rasoul; Asturiano, Juan F; Weltzien, Finn-Arne; Pérez, Luz

    2015-09-01

    Activation at fertilization of the vertebrate egg is triggered by Ca(2+) waves. Recent studies suggest the phospholipase C zeta (PLCζ), a sperm-specific protein, triggers egg activation by an IP3-mediated Ca(2+) release and allow Ca(2+) waves at fertilization. In the present study we cloned, characterized, and phylogenetically positioned the European eel PLCζ (PLCζ1). It is 1521 bp long, with 10 exons encoding an open reading frame of 506 amino acids. The amino acid sequence contains an EF-hand domain, X and Y catalytic domains, and a carboxy-terminal C2 domain, all typical of other PLCζ orthologous. The tissue distribution was studied, and the gene expression was determined in testis during induced sexual maturation at three different thermal regimes. Also, brain and pituitary expression was studied through sex maturation at constant temperature. plcζ1 was expressed in brain of male and female, in testis but not in ovaries. By first time in vertebrates, it is reported plcζ1 expression in the pituitary gland. Testis plcζ1 expression increased through spermatogenesis under all the thermal regimes, but being significantly elevated at lower temperatures. It was very low when testis contained only spermatogonia or spermatocytes, while maximum expression was found during spermiogenesis. These results support the hypothesis for an eel sperm-specific PLCζ1 inducing egg activation, similarly to mammals and some teleosts, but different from some other teleost species, which express this protein in ovaries, but not in testes. PMID:26051612

  8. Sperm competition and the evolution of gamete morphology in frogs.

    PubMed

    Byrne, Phillip G; Simmons, Leigh W; Roberts, J Dale

    2003-10-01

    Despite detailed knowledge of the ultrastructure of spermatozoa, there is a paucity of information on the selective pressures that influence sperm form and function. Theoretical models for both internal and external fertilizers predict that sperm competition could favour the evolution of longer sperm. Empirical tests of the external-fertilization model have been restricted to just one group, the fishes, and these tests have proved equivocal. We investigated how sperm competition affects sperm morphology in externally fertilizing myobatrachid frogs. We also examined selection acting on egg size, and covariation between sperm and egg morphology. Species were ranked according to probability of group spawning and hence risk of sperm competition. Body size, testis size and oviposition environment may also influence gamete traits and were included in our analyses. After controlling for phylogenetic relationships between the species examined, we found that an increased risk of sperm competition was associated with increased sperm head and tail lengths. Path analysis showed that sperm competition had its greatest direct effect on sperm tail length, as might be expected under selection resulting from competitive fertilization. Sperm competition did not influence egg size. Oviposition location had a strong influence on egg size and a weak influence on sperm length, with terrestrial spawners having larger gametes than aquatic spawners. Our analysis revealed significant correlated evolution between egg morphology and sperm morphology. These data provide a conclusive demonstration that sperm competition selects for increased sperm length in frogs, and evidence for evolutionary covariance between aspects of male and female gamete morphology. PMID:14561298

  9. Increasing productivity through Total Reuse Management (TRM)

    NASA Technical Reports Server (NTRS)

    Schuler, M. P.

    1991-01-01

    Total Reuse Management (TRM) is a new concept currently being promoted by the NASA Langley Software Engineering and Ada Lab (SEAL). It uses concepts similar to those promoted in Total Quality Management (TQM). Both technical and management personnel are continually encouraged to think in terms of reuse. Reuse is not something that is aimed for after a product is completed, but rather it is built into the product from inception through development. Lowering software development costs, reducing risk, and increasing code reliability are the more prominent goals of TRM. Procedures and methods used to adopt and apply TRM are described. Reuse is frequently thought of as only being applicable to code. However, reuse can apply to all products and all phases of the software life cycle. These products include management and quality assurance plans, designs, and testing procedures. Specific examples of successfully reused products are given and future goals are discussed.

  10. Exploring Increased Productivity Through Employee Engagement

    NASA Astrophysics Data System (ADS)

    Richards, Wayne K., Jr.

    Disengaged employees cost U.S. companies billions of dollars annually in lowered productivity, a cost which has been compounded by the difficult economic situations in the country. The potential for increasing productivity through increased employee engagement was examined in this study. Using personal engagement theory and the theory of planned behavior, the purpose of this phenomenological study was to explore how the experiences of salaried aerospace employees affected productivity and the financial performance of an organization. Interviews were conducted with a purposive sample of 20 aerospace employees whose responses were codified and analyzed to identify themes. The analysis indicated that (a) the lived experiences of employees influenced employee engagement, (b) employee engagement affects organizational commitment and performance, and (c) trust and respect and leadership are essential components to keep employees engaged. Eighty percent of the participants indicated that as employee engagement increases so too does organizational performance. The implications for positive social change include new insights for leaders seeking to increase productivity and financial performance, and to support employee engagement for maintaining sustainability, retaining talent, increasing profits, and improving the economy.

  11. Reheat furnace upgrade results in production increase

    SciTech Connect

    Burns, A.H.; Fuhrman, F.L.

    1997-02-01

    This project is a unique example of the technique of high-intensity convective heating for generating significant material preheating that can be used to increase furnace production rate. The mathematical model predicted a production increase of 17%. The furnace has demonstrated a 22% higher sustained production rate. Oxidation rates have been gradually reduced and will be improved further by the installation of level 2 controls. The burner systems have proved to be reliable in a harsh operating environment. There has been a small improvement in the specific fuel consumption. In the case of a top-fired reheat furnace, convective pre-heating installed at the charge end of the furnace will result in a significant increase in production rate. The static thermal model developed for this project is a reliable tool for the prediction of performance of the modified furnace. The use of the high-velocity burners in the mixing zone was an effective substitute for the customary baffle wall. The installation had the benefit of preventing over-pressurization of the furnace discharge doors and enabled the operator to achieve a considerable improvement in pressure control. In addition, the removal of the baffle wall eliminated the shadowing effect where the incoming load is shaded from radiation from the heating zone. Additional turbulence in the mixing zone also had a significant impact by increasing the amount of heat removed from flue gas before it is vented from the furnace.

  12. Increasing Sales by Developing Production Consortiums.

    ERIC Educational Resources Information Center

    Smith, Christopher A.; Russo, Robert

    Intended to help rehabilitation facility administrators increase organizational income from manufacturing and/or contracted service sources, this document provides a decision-making model for the development of a production consortium. The document consists of five chapters and two appendices. Chapter 1 defines the consortium concept, explains…

  13. Aspermy, Sperm Quality and Radiation in Chernobyl Birds

    PubMed Central

    Møller, Anders Pape; Bonisoli-Alquati, Andrea; Mousseau, Timothy A.; Rudolfsen, Geir

    2014-01-01

    Background Following the Chernobyl nuclear power plant accident, large amounts of radionuclides were emitted and spread in the environment. Animals living in such contaminated areas are predicted to suffer fitness costs including reductions in the quality and quantity of gametes. Methodology/Principal Findings We studied whether aspermy and sperm quality were affected by radioactive contamination by examining ejaculates from wild caught birds breeding in areas varying in background radiation level by more than three orders of magnitude around Chernobyl, Ukraine. The frequency of males with aspermy increased logarithmically with radiation level. While 18.4% of males from contaminated areas had no sperm that was only the case for 3.0% of males from uncontaminated control areas. Furthermore, there were negative relationships between sperm quality as reflected by reduced sperm velocity and motility, respectively, and radiation. Conclusions/Significance Our results suggest that radioactive contamination around Chernobyl affects sperm production and quality. We are the first to report an interspecific difference in sperm quality in relation to radioactive contamination. PMID:24963711

  14. Cryoprotective effect of phosphorous-containing phenolic anti-oxidant for the cryopreservation of beluga sperm.

    PubMed

    Osipova, V P; Kolyada, M N; Berberova, N T; Milaeva, E R; Ponomareva, E N; Belaya, M M

    2014-12-01

    A cryoprotective effect of an addition of a new synthetic antioxidant - a representative of phosphorus-containing sterically hindered phenols is presented. The efficiency of the compound was shown to exceed the effect of lipid-soluble antioxidants butylated hydroxytoluene (BHT) and trolox in the conditions of cryopreservation of beluga sperm in the presence of the modified Stein's medium. It was shown that the level of carbonyl oxidation by-products, which can react with thiobarbituric acid (TBARS), in beluga sperm was inversely proportional to the motility time of sperm cells. The fertility of beluga sperm increased 2 times upon the addition of phosphorus-containing phenol to a modified Stein's medium. The prospects of the new antioxidant application to improve cryoresistance of beluga sperm in the conditions of cryopreservation for its efficient protection from the peroxidation processes are discussed. PMID:25445463

  15. Effect of calcium, bicarbonate, and albumin on capacitation-related events in equine sperm.

    PubMed

    Macías-García, B; González-Fernández, L; Loux, S C; Rocha, A M; Guimarães, T; Peña, F J; Varner, D D; Hinrichs, K

    2015-01-01

    Repeatable methods for IVF have not been established in the horse, reflecting the failure of standard capacitating media to induce changes required for fertilization capacity in equine sperm. One important step in capacitation is membrane cholesterol efflux, which in other species is triggered by cholesterol oxidation and is typically enhanced using albumin as a sterol acceptor. We incubated equine sperm in the presence of calcium, BSA, and bicarbonate, alone or in combination. Bicarbonate induced an increase in reactive oxygen species (ROS) that was abolished by the addition of calcium or BSA. Bicarbonate induced protein tyrosine phosphorylation (PY), even in the presence of calcium or BSA. Incubation at high pH enhanced PY but did not increase ROS production. Notably, no combination of these factors was associated with significant cholesterol efflux, as assessed by fluorescent quantitative cholesterol assay and confirmed by filipin staining. By contrast, sperm treated with methyl-β-cyclodextrin showed a significant reduction in cholesterol levels, but no significant increase in PY or ROS. Presence of BSA increased sperm binding to bovine zonae pellucidae in all three stallions. These results show that presence of serum albumin is not associated with a reduction in membrane cholesterol levels in equine sperm, highlighting the failure of equine sperm to exhibit core capacitation-related changes in a standard capacitating medium. These data indicate an atypical relationship among cholesterol efflux, ROS production, and PY in equine sperm. Our findings may help to elucidate factors affecting failure of equine IVF under standard conditions. PMID:25349439

  16. Chromosomal abnormalities in human sperm

    SciTech Connect

    Martin, R.H.

    1985-01-01

    The ability to analyze human sperm chromosome complements after penetration of zona pellucida-free hamster eggs provides the first opportunity to study the frequency and type of chromosomal abnormalities in human gametes. Two large-scale studies have provided information on normal men. We have studied 1,426 sperm complements from 45 normal men and found an abnormality rate of 8.9%. Brandriff et al. (5) found 8.1% abnormal complements in 909 sperm from 4 men. The distribution of numerical and structural abnormalities was markedly dissimilar in the 2 studies. The frequency of aneuploidy was 5% in our sample and only 1.6% in Brandriff's, perhaps reflecting individual variability among donors. The frequency of 24,YY sperm was low: 0/1,426 and 1/909. This suggests that the estimates of nondisjunction based on fluorescent Y body data (1% to 5%) are not accurate. We have also studied men at increased risk of sperm chromosomal abnormalities. The frequency of chromosomally unbalanced sperm in 6 men heterozygous for structural abnormalities varied dramatically: 77% for t11;22, 32% for t6;14, 19% for t5;18, 13% for t14;21, and 0% for inv 3 and 7. We have also studied 13 cancer patients before and after radiotherapy and demonstrated a significant dose-dependent increase of sperm chromosome abnormalities (numerical and structural) 36 months after radiation treatment.

  17. Increasing the availability of national mapping products.

    USGS Publications Warehouse

    Roney, J.I.; Ogilvie, B.C.

    1981-01-01

    A discussion of the means employed by the US Geological Survey to facilitate map usage, covering aspects of project Map Accessibility Program including special rolled and folded map packaging, new market testing, parks and campgrounds program, expanded map dealer program, new booklet-type State sales index and catalog and new USGS map reference code. The USGS is seen as the producer of a tremendous nation-wide inventory of topographic and related map products available in unprecedented types, formats and scales, and as endeavouring to increase access to its products. The new USGS map reference code is appended. -J.C.Stone

  18. Engineering Rhodosporidium toruloides for increased lipid production.

    PubMed

    Zhang, Shuyan; Skerker, Jeffrey M; Rutter, Charles D; Maurer, Matthew J; Arkin, Adam P; Rao, Christopher V

    2016-05-01

    Oleaginous yeast are promising organisms for the production of lipid-based chemicals and fuels from simple sugars. In this work, we explored Rhodosporidium toruloides for the production of lipid-based products. This oleaginous yeast natively produces lipids at high titers and can grow on glucose and xylose. As a first step, we sequenced the genomes of two strains, IFO0880, and IFO0559, and generated draft assemblies and annotations. We then used this information to engineer two R. toruloides strains for increased lipid production by over-expressing the native acetyl-CoA carboxylase and diacylglycerol acyltransferase genes using Agrobacterium tumefaciens mediated transformation. Our best strain, derived from IFO0880, was able to produce 16.4 ± 1.1 g/L lipid from 70 g/L glucose and 9.5 ± 1.3 g/L lipid from 70 g/L xylose in shake-flask experiments. This work represents one of the first examples of metabolic engineering in R. toruloides and establishes this yeast as a new platform for production of fatty-acid derived products. Biotechnol. Bioeng. 2016;113: 1056-1066. © 2015 Wiley Periodicals, Inc. PMID:26479039

  19. The effects of male age on sperm DNA damage in healthy non-smokers

    SciTech Connect

    Schmid, T; Eskenazi, B; Baumgartner, A; Marchetti, F; Young, S; Weldon, R; Anderson, D; Wyrobek, A

    2006-03-08

    The trend for men to have children at older ages raises concerns that advancing age may increase the production of genetically defective sperm, increasing the risks of transmitting germ-line mutations. We investigated the associations between male age and sperm DNA damage and the influence of several lifestyle factors in a healthy non-clinical group of 80 non-smokers (age: 22-80) with no known fertility problems using the sperm Comet analyses. The average percent of DNA that migrated out of the sperm nucleus under alkaline electrophoresis increased with age (0.18% per year, p=0.006); but there was no age association for damage measured under neutral conditions (p=0.7). Men who consumed >3 cups coffee per day had {approx}20% higher % tail DNA under neutral but not alkaline conditions compared to men who consumed no caffeine (p=0.005). Our findings indicate that (a) older men have increased sperm DNA damage associated with alkali-labile sites or single-strand DNA breaks, and (b) independent of age, men with substantial daily caffeine consumption have increased sperm DNA damage associated with double-strand DNA breaks. DNA damage in sperm can be converted to chromosomal aberrations and gene mutations after fertilization increasing the risks for developmental defects and genetic diseases among offspring.

  20. Copulation Activity, Sperm Production and Conidia Transfer in Aedes aegypti Males Contaminated by Metarhizium anisopliae: A Biological Control Prospect

    PubMed Central

    Russell, Tanya L.; Braks, Marieta A. H.

    2015-01-01

    Background Dengue is the most prevalent arboviral disease transmitted by Aedes aegypti worldwide, whose chemical control is difficult, expensive, and of inconsistent efficacy. Releases of Metarhizium anisopliae—exposed Ae. aegypti males to disseminate conidia among female mosquitoes by mating represents a promising biological control approach against this important vector. A better understanding of fungus virulence and impact on reproductive parameters of Ae. aegypti, is need before testing auto-dissemination strategies. Methodology/Principal Findings Mortality, mating competitiveness, sperm production, and the capacity to auto-disseminate the fungus to females up to the 5thcopulation, were compared between Aedes aegypti males exposed to 5.96 x 107 conidia per cm2 of M. anisopliae and uninfected males. Half (50%) of fungus-exposed males (FEMs) died within the first 4 days post-exposure (PE). FEMs required 34% more time to successively copulate with 5 females (165 ± 3 minutes) than uninfected males (109 ± 3 minutes). Additionally, fungus infection reduced the sperm production by 87% at 5 days PE. Some beneficial impacts were observed, FEMs were able to successfully compete with uninfected males in cages, inseminating an equivalent number of females (about 25%). Under semi-field conditions, the ability of FEMs to search for and inseminate females was also equivalent to uninfected males (both inseminating about 40% females); but for the remaining females that were not inseminated, evidence of tarsal contact (transfer of fluorescent dust) was significantly greater in FEMs compared to controls. The estimated conidia load of a female exposed on the 5th copulation was 5,200 mL-1 which was sufficient to cause mortality. Conclusion/Significance Our study is the first to demonstrate auto-dissemination of M. anisopliae through transfer of fungus from males to female Ae. aegypti during mating under semi-field conditions. Our results suggest that auto-dissemination studies

  1. Imbalanced lipid homeostasis in the conditional Dicer1 knockout mouse epididymis causes instability of the sperm membrane.

    PubMed

    Björkgren, Ida; Gylling, Helena; Turunen, Heikki; Huhtaniemi, Ilpo; Strauss, Leena; Poutanen, Matti; Sipilä, Petra

    2015-02-01

    During epididymal sperm maturation, the lipid content of the sperm membrane is modified, which facilitates sperm motility and fertility. However, little is known about the mechanisms regulating the maturation process. By generating a conditional knockout (cKO) of Dicer1 in the proximal part of the mouse epididymis, we studied the role of RNA interference in epididymal functions. The Dicer1 cKO epididymis displayed an altered lipid homeostasis associated with a 0.6-fold reduction in the expression of the gene elongation of very long chain fatty acids-like 2, an enzyme needed for production of long-chain polyunsaturated fatty acids (PUFAs). Furthermore, the expression of several factors involved in cholesterol synthesis was up-regulated. Accordingly, the Dicer1 cKO sperm membrane showed a 0.7-fold decrease in long-chain PUFAs, whereas the amount of cholesterol in acrosome-reacted sperm displayed a 1.7-fold increase. The increased cholesterol:PUFA ratio of the sperm membrane caused breakage of the neck and acrosome region and immotility of sperm. Dicer1 cKO mice sperm also displayed reduced ability to bind to and fertilize the oocyte in vitro. This study thus shows that Dicer1 is critical for lipid synthesis in the epididymis, which directly affects sperm membrane integrity and male fertility. PMID:25366345

  2. Computer-assisted sperm analysis (CASA): capabilities and potential developments.

    PubMed

    Amann, Rupert P; Waberski, Dagmar

    2014-01-01

    Computer-assisted sperm analysis (CASA) systems have evolved over approximately 40 years, through advances in devices to capture the image from a microscope, huge increases in computational power concurrent with amazing reduction in size of computers, new computer languages, and updated/expanded software algorithms. Remarkably, basic concepts for identifying sperm and their motion patterns are little changed. Older and slower systems remain in use. Most major spermatology laboratories and semen processing facilities have a CASA system, but the extent of reliance thereon ranges widely. This review describes capabilities and limitations of present CASA technology used with boar, bull, and stallion sperm, followed by possible future developments. Each marketed system is different. Modern CASA systems can automatically view multiple fields in a shallow specimen chamber to capture strobe-like images of 500 to >2000 sperm, at 50 or 60 frames per second, in clear or complex extenders, and in <2 minutes, store information for ≥ 30 frames and provide summary data for each spermatozoon and the population. A few systems evaluate sperm morphology concurrent with motion. CASA cannot accurately predict 'fertility' that will be obtained with a semen sample or subject. However, when carefully validated, current CASA systems provide information important for quality assurance of semen planned for marketing, and for the understanding of the diversity of sperm responses to changes in the microenvironment in research. The four take-home messages from this review are: (1) animal species, extender or medium, specimen chamber, intensity of illumination, imaging hardware and software, instrument settings, technician, etc., all affect accuracy and precision of output values; (2) semen production facilities probably do not need a substantially different CASA system whereas biology laboratories would benefit from systems capable of imaging and tracking sperm in deep chambers for a flexible

  3. Increased productivity in flight with voice commanding

    NASA Technical Reports Server (NTRS)

    Jordan, W. T.

    1985-01-01

    Automatic Speech Recognition technology has matured to the point where it can provide a viable means of increasing productivity by naturalizing the man-machine interface. With ever increasing workloads being placed on astronauts, speech recognition may provide an alternative means of system controlling that would reduce the task burden. Voice commanding, allowing hands-free operation, can be especially effective during operations requiring simultaneous system control. A flight experiment is under development to demonstrate the operational effectiveness of voice control by commanding the Space Shuttle's Closed Circuit Television (CCIV) system. This experiment will help direct future applications of voice entry to space operations.

  4. Ejaculated Mouse Sperm Enter Cumulus-Oocyte Complexes More Efficiently In Vitro than Epididymal Sperm

    PubMed Central

    Suarez, Susan S.

    2015-01-01

    The mouse is an established and popular animal model for studying reproductive biology. Epididymal mouse sperm, which lack exposure to secretions of male accessory glands and do not precisely represent ejaculated sperm for the study of sperm functions, have been almost exclusively used in studies. We compared ejaculated and epididymal sperm in an in vitro fertilization setting to examine whether ejaculated sperm enter cumulus-oocyte complexes more efficiently. In order to prepare sperm for fertilization, they were incubated under capacitating conditions. At the outset of incubation, ejaculated sperm stuck to the glass surfaces of slides and the incidences of sticking decreased with time; whereas, very few epididymal sperm stuck to glass at any time point, indicating differences in surface charge. At the end of the capacitating incubation, when sperm were added to cumulus-oocyte complexes, the form of flagellar movement differed dramatically; specifically, ejaculated sperm predominantly exhibited increased bending on one side of the flagellum (a process termed pro-hook hyperactivation), while epididymal sperm equally exhibited increased bending on one or the other side of the flagellum (pro-hook or anti-hook hyperactivation). This indicates that accessory sex gland secretions might have modified Ca2+ signaling activities in sperm, because the two forms of hyperactivation are reported to be triggered by different Ca2+ signaling patterns. Lastly, over time, more ejaculated than epididymal sperm entered the cumulus oocyte complexes. We concluded that modification of sperm by male accessory gland secretions affects the behavior of ejaculated sperm, possibly providing them with an advantage over epididymal sperm for reaching the eggs in vivo. PMID:25996155

  5. Competition drives cooperation among closely-related sperm of deer mice

    PubMed Central

    Fisher, Heidi S.; Hoekstra, Hopi E.

    2009-01-01

    Among the extraordinary adaptations driven by sperm competition is the cooperative behaviour of spermatozoa1. By forming cooperative groups, sperm can increase their swimming velocity and thereby gain an advantage in intermale sperm competition1,2. Accordingly, selection should favour cooperation of the most closely related sperm to maximize fitness3. Here we show that sperm of deer mice (genus Peromyscus) form motile aggregations, then we use this system test predictions of sperm cooperation. We first show that sperm aggregate more often with conspecific than heterospecific sperm, suggesting that individual sperm can discriminate based on genetic relatedness. Next, we provide evidence that the cooperative behaviour of closely-related sperm is driven by sperm competition. In a monogamous species lacking sperm competition, P. polionotus, sperm indiscriminately group with unrelated conspecific sperm. In contrast, in the highly promiscuous deer mouse, P. maniculatus, sperm are significantly more likely to aggregate with those obtained from the same male than sperm from an unrelated conspecific donor. Even when we test sperm from sibling males, we continue to see preferential aggregations of related sperm in P. maniculatus. These results suggest that sperm from promiscuous deer mice discriminate among relatives and thereby cooperate with the most closely-related sperm, an adaptation likely driven by sperm competition. PMID:20090679

  6. Artificial insemination with donor sperm (AID): heterogeneity in sperm banking facilities in a single country (Belgium).

    PubMed

    Thijssen, A; Dhont, N; Vandormael, E; Cox, A; Klerkx, E; Creemers, E; Ombelet, W

    2014-01-01

    Due to the high inflow of foreign patients seeking cross-border reproductive care in Belgium and the increased number of lesbian couples and single women who call for artificial insemination with donor sperm (AID), Belgian sperm banks nowadays face a shortage in donor sperm. However, since there is no central registration system for sperm donors in Belgium, no figures are currently available supporting this statement. Therefore a study was performed to obtain a detailed overview of the sperm banking facilities in Belgium. Questionnaires were sent to all Belgian centres for assisted reproduction with laboratory facilities (n = 18) to report on their sperm banking methods. The results showed that 82% of the centres rely partially or completely on foreign donor sperm. Moreover, four of the thirteen centres that have their own sperm bank use imported donor sperm in > 95% AID cycles. Our results show that in 63% of the Belgian AID cycles imported Danish donor sperm is being used. Donor recruitment is mainly performed through the centre's website (61%) or by distributing flyers in the centre (46%) and 9 to 180 potential donors have been recruited per centre in 2013. Eventually, 15 to 50% of these candidate donors were accepted. Different criteria for donor acceptance are handled by the centres: donor age limits range from 18-25 to 36-46 years old, and thresholds for sperm normality differ considerably. We can conclude that a wide variation in methods associated with sperm banking is observed in Belgian centres. PMID:25009728

  7. Maturity stage and plasma testosterone levels are related to sperm production in blue catfish Ictalurus furcatus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recently, the channel catfish, Ictalurus puntatus' X blue catfish, I.furcatus ' F1 hybrid has demonstrated good potential for commercial production compared to the commonly raised channel catfish. Efforts by researchers and commercial producers in the last 40 years have improved hybrid fry product...

  8. Sperm viability - Determination of sperm viability using fluorescence microscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To determine the percentage of viable sperm in a semen sample using stains that differentiates viable (live) sperm from nonviable (dead) sperm. Viable sperm are detected by SYBR-14, which stains the sperm nuclei green. Nonviable sperm are detected by propidium iodide (PI), which stains the sperm red...

  9. Exposure to bisphenol A (BPA) in Wistar rats reduces sperm quality with disruption of ERK signal pathway.

    PubMed

    Li, Juan; Mao, Rui; Zhou, Qin; Ding, Ling; Tao, Jin; Ran, Mao-Mei; Gao, Er-Sheng; Yuan, Wei; Wang, Jin-Tao; Hou, Li-Fang

    2016-03-01

    Bisphenol A (BPA) is an estrogenic environmental toxin widely used in the production of plastics and ubiquitous human exposure to this chemical has been proposed to be a potential risk to human health. Exposure to BPA can negatively impact sperm quality. However, the mechanism remains largely unknown. The objectives of this study were to assess the role of BPA on sperm quality and explore the possible mechanisms. The Wistar male rats (aged 28 days) were administered BPA by oral gavage for 28 days at dose of 50, 100 and 200 mg/kg/day; meanwhile, the negative control with corn oil (0 mg/kg/day BPA) and positive control with E2 at the dose of 100 μg/kg/day. The sperm density, sperm activity and sperm survival rate were analyzed byCASA system, and the sperm abnormality rate was analyzed by improved Papanicolaou stained. The protein expression levels of Src/p-Src, ERK1/2, p-ERK1/2 and CREB/p-CREB were detected by Western bolt. The results showed that the body weight gain, testes weight, testis coefficient, sperm density, sperm activity, sperm survival rate and protein expression levels of p-ERK1, p-ERK2 and p-CREB decreased, but the sperm abnormality rate increased with increasing BPA concentrations. There were positive correlations between sperm density, sperm activity and sperm survival rate with protein expression levels of p-ERK1, p-ERK2 and p-CREB, and negative correlations between sperm abnormality rate with the protein expression levels of p-ERK1, p-ERK2 and p-CREB. Results from the structural equation model demonstrated that BPA retained a significant negative effect to p-ERK, whereas p-ERK retained a significant positive effect to sperm quality and acted as the mediate variable. This study provides a novel insight regarding the potential role of p-ERK1 and p-ERK2 protein kinase on reproductive toxicity of BPA. The adverse effects of BPA on adult male sperm quality may be through the induction of the disruption of ERK signal pathway. However, additional

  10. Effect of cinnamon (Cinnamomum zeylanicum) bark oil on heat stress-induced changes in sperm production, testicular lipid peroxidation, testicular apoptosis, and androgenic receptor density in developing Japanese quails.

    PubMed

    Türk, Gaffari; Şimşek, Ülkü G; Çeribaşı, Ali O; Çeribaşı, Songül; Özer Kaya, Şeyma; Güvenç, Mehmet; Çiftçi, Mehmet; Sönmez, Mustafa; Yüce, Abdurrauf; Bayrakdar, Ali; Yaman, Mine; Tonbak, Fadime

    2015-08-01

    The aim of this study was to investigate the effect of cinnamon bark oil (CBO) on heat stress (HS)-induced changes in sperm production, testicular lipid peroxidation, testicular apoptosis, and androgenic receptor (AR) density in developing Japanese quails. Fifteen-day-old 90 male chicks were assigned to two main groups. The first group (45 chicks) was kept in a thermoneutral room at 22 °C for 24 h/day. The second group (45 chicks) was kept in a room with high ambient temperature at 34 °C for 8 h/day (from 9 AM-5 PM) and at 22 °C for 16 h/day. Each of these two main groups was then divided into three subgroups (CBO groups 0, 250, 500 ppm) consisting of 15 chicks (six treatment groups in 2 × 3 factorial order). Each of subgroups was replicated for three times and each replicate included five chicks. Heat stress caused significant decreases in body weight, spermatid and testicular sperm numbers, the density of testicular Bcl-2 (antiapoptotic marker) and AR immunopositivity, and significant increases in testicular lipid peroxidation level, the density of testicular Bax (apoptotic marker) immunopositivity, and a Bax/Bcl-2 ratio along with some histopathologic damages. However, 250 and 500 ppm CBO supplementation provided significant improvements in HS-induced increased level of testicular lipid peroxidation, decreased number of spermatid and testicular sperm, decreased densities of Bcl-2 and AR immunopositivity, and some deteriorated testicular histopathologic lesions. In addition, although HS did not significantly affect the testicular glutathione level, addition of both 250 and 500 ppm CBO to diet of quails reared in both HS and thermoneutral conditions caused a significant increase when compared with quails without any consumption of CBO. In conclusion, HS-induced lipid peroxidation causes testicular damage in developing male Japanese quails and, consumption of CBO, which has antiperoxidative effect, protects their testes against HS. PMID:25913274

  11. Evaluation of activation treatments for blastocyst production and birth of viable calves following bovine intracytoplasmic sperm injection.

    PubMed

    Oikawa, T; Takada, N; Kikuchi, T; Numabe, T; Takenaka, M; Horiuchi, T

    2005-04-01

    The objective of this study was to compare the effectiveness of different methods of bovine oocyte activation following intracytoplasmic sperm injection (ICSI) in terms of oocyte cleavage and blastocyst rates, and calf production. Oocytes were harvested, post mortem, from the ovaries of Japanese Black heifers or cows. ICSI was carried out using a piezo-electric actuator. The injected or sham-injected oocytes that were assigned to three activation treatments, each replicated three times, were studied: (1) exposure to 5 microM ionomycin for 5 min (ionomycin); (2) exposure to 5 microM ionomycin for 5 min followed by culture in TCM199 for 3 h and a further 3h culture in 1.9 mM 6-dimethylaminopurine (DMAP-ionomycin+DMAP); (3) exposure to 7% ethanol in TCM199 for 5 min, 4 h after ICSI (ethanol). One or two blastocysts from the ionomycin+DMAP (8 recipients) and ethanol (17 recipients) oocyte activation treatments were non-surgically transferred into Holsteins for the study of calf production. The highest cleavage and blastocyst production rates were observed in the ionomycin+DMAP treatment (83.9% and 40.1%) by the ICSI. These rates were significantly (P<0.05) higher than those for the ionomycin oocyte activation treatment (57.6% and 18.2%) but did not differ from the ethanol treatment (75.6% and 29.4%). In the sham-injected, the highest blastocyst production rates were observed for the ionomycin+DMAP and ethanol treatments (10.7% and 11.3%). Pregnancy and birth rates for blastocysts derived from the ethanol oocyte activation treatment (58.8% and 47.4%) were significantly higher (P<0.05) than those of the ionomycin+DMAP treatment (12.5% and 9.2%). The results showed that post-ICSI oocyte activation with ethanol is more effective than activation with ionomycin alone or with ionomycin+DMAP for the production of viable blastocysts and calves. PMID:15766799

  12. ESP's placed in horizontal lateral increase production

    SciTech Connect

    Gallup, A.; Wilson, B.L. ); Marshall, R. )

    1990-06-18

    By design, the electric submersible pump (ESP) is an effective method of lifting fluids from horizontal wells. But this ESP application does have unique installation and operating parameters that need to be considered. ESP's have been used for many years in directional wells. This application provides an experience base for understanding deflection limits on the unit. To avoid damaging the ESP, special equipment may be required in some horizontal installations. This paper discusses how several ESP's have been designed specifically for medium-radius wells. In these applications, the deeper pump setting provides for a significant increase in production rate. In general, to realize the full benefit of a horizontal installation, the ESP should be considered when planning, drilling, and completing the well.

  13. Sperm competitiveness in frogs: slow and steady wins the race.

    PubMed

    Dziminski, Martin A; Roberts, J Dale; Beveridge, Maxine; Simmons, Leigh W

    2009-11-22

    When sperm compete to fertilize available ova, selection is expected to favour ejaculate traits that contribute to a male's fertilization success. While there is much evidence to show that selection favours increased numbers of sperm, only a handful of empirical studies have examined how variation in sperm form and function contributes to competitive fertilization success. Here, we examine selection acting on sperm form and function in the externally fertilizing myobatrachid frog, Crinia georgiana. Using in vitro fertilization techniques and controlling for variation in the number of sperm contributed by males in competitive situations, we show that males with a greater proportion of motile sperm, and motile sperm with slower swimming velocities, have an advantage when competing for fertilizations. Sperm morphology and the degree of genetic similarity between putative sires and the female had no influence on competitive fertilization success. These unusual patterns of selection might explain why frog sperm typically exhibit relatively slow swimming speeds and sustained longevity. PMID:19710059

  14. Sperm specific proteins-potential candidate molecules for fertility control

    PubMed Central

    Suri, Anil

    2004-01-01

    The increase in population growth rate warrants the development of additional contraceptive methods that are widely acceptable, free from side effects and less expensive. Immunocontraception, and in particular the targeting of antibodies to gamete-specific antigens implicated in sperm egg binding and fertilization, offers an attractive approach to control fertility. The development of a contraceptive vaccine based on sperm antigen represents a promising approach to contraception. In mammals, fertilization is completed by the direct interaction of sperm and egg, a process mediated primarily by sperm surface proteins. Sperm have proteins that are unique, cell specific, immunogenic and accessible to antibodies. A few of the sperm specific proteins have been isolated and characterized. The antibodies raised against the sperm specific antigens have proved to be extremely effective at reducing sperm-egg interaction in vitro; fertility trials in sub-human primates would eventually prove the effectiveness of the sperm antigens in terms of contraceptive efficacy. PMID:15012833

  15. Increased biogas production using microbial stimulants.

    PubMed

    Singh, S; Kumar, S; Jain, M C; Kumar, D

    2001-07-01

    Laboratory studies were undertaken to evaluate the effect of microbial stimulants Aquasan and Teresan, on biogas yields from cattle dung and combined residues of cattle dung and kitchen waste, respectively. The addition of single dose of Aquasan at the rate of 10, 15 and 20 ppm to cattle dung on the first day of incubation resulted in increased gas yields ranging between 45.1 and 62.1 l/kg dry matter. Subsequent addition of Aquasan at 15 and 20 ppm dosage after a period of 15 days increased the gas yields by 15-16%. The gas production was found to be optimum at a dosage level of 15 ppm and was 39% and 55% higher with single and dual additions, respectively, than untreated cattle dung. In another bench scale study (1:1 dry matter) the addition of Teresan at 10 ppm concentration to the mixed residues of cattle dung and kitchen wastes at different solids concentration, produced 34.8% more gas (272.4 l/kg d.m.) than the uninoculated mixture at 15% TS concentration (202.4 l/kg d.m.). PMID:11341694

  16. Sperm motility of externally fertilizing fish and amphibians.

    PubMed

    Browne, R K; Kaurova, S A; Uteshev, V K; Shishova, N V; McGinnity, D; Figiel, C R; Mansour, N; Agney, D; Wu, M; Gakhova, E N; Dzyuba, B; Cosson, J

    2015-01-01

    We review the phylogeny, sperm competition, morphology, physiology, and fertilization environments of the sperm of externally fertilizing fish and amphibians. Increased sperm competition in both fish and anurans generally increases sperm numbers, sperm length, and energy reserves. The difference between the internal osmolarity and iconicity of sperm cells and those of the aquatic medium control the activation, longevity, and velocity of sperm motility. Hypo-osmolarity of the aquatic medium activates the motility of freshwater fish and amphibian sperm and hyperosmolarity activates the motility of marine fish sperm. The average longevity of the motility of marine fish sperm (~550 seconds) was significantly (P < 0.05) greater than that of freshwater fish sperm (~150 seconds), with the longevities of both marine and freshwater fish being significantly (P < 0.05) lower than that of anuran sperm (~4100 seconds). The average velocity of anuran sperm (25 μm/s) was significantly (P < 0.05) lower than that of marine fish (140 μm/s) or freshwater fish (135 μm/s) sperm. The longevity of the sperm of giant salamanders (Cryptobranchoidea) of approximately 600 seconds was greater than that of freshwater fish sperm but much lower than anuran sperm. Our research and information from the literature showed that higher osmolarities promote greater longevity in anuran sperm, and some freshwater fish sperm, and that anuran and cryptobranchid sperm maintained membrane integrity long after the cessation of motility, demonstrating a preferential sharing of energy reserves toward the maintenance of membrane integrity. The maintenance of the membrane integrity of anuran sperm in fresh water for up to 6 hours showed an extremely high osmotic tolerance relative to fish sperm. The very high longevity and osmotic tolerance of anuran sperm and high longevity of cryptobranchid sperm, relative to those of freshwater fish, may reflect the complex fertilization history of amphibian sperm in

  17. Cryopreservation of Fish Sperm

    NASA Astrophysics Data System (ADS)

    Kurokura, Hisashi

    Present status of research activities in cryopreservation of fish gamete in aquaculture field was introduced. More than 59 fish species have been reported in the research histories and nearly half of them were studied during recent 10 years. This means that the research activities are increasing, though commercial profit have not obtained yet. Fish species of which sperm can successfully cryopreserved is still limited comparing to numerous species in telost. One of the major obstacle for improvement of the technique is existence of wide specie specific variance in the freezing tolerance of fish sperm. The varianc can possibly be explaind thorugh the informations obtained by the studies in comparative spermatology, which is recently activated field in fish biology.

  18. Hypercholesterolemia Impaired Sperm Functionality in Rabbits

    PubMed Central

    Monclus, Maria A.; Cabrillana, Maria E.; Clementi, Marisa A.; Espínola, Leandro S.; Cid Barría, Jose L.; Vincenti, Amanda E.; Santi, Analia G.; Fornés, Miguel W.

    2010-01-01

    Hypercholesterolemia represents a high risk factor for frequent diseases and it has also been associated with poor semen quality that may lead to male infertility. The aim of this study was to analyze semen and sperm function in diet-induced hypercholesterolemic rabbits. Twelve adult White New Zealand male rabbits were fed ad libitum a control diet or a diet supplemented with 0.05% cholesterol. Rabbits under cholesterol-enriched diet significantly increased total cholesterol level in the serum. Semen examination revealed a significant reduction in semen volume and sperm motility in hypercholesterolemic rabbits (HCR). Sperm cell morphology was seriously affected, displaying primarily a “folded head”-head fold along the major axe-, and the presence of cytoplasmic droplet on sperm flagellum. Cholesterol was particularly increased in acrosomal region when detected by filipin probe. The rise in cholesterol concentration in sperm cells was determined quantitatively by Gas chromatographic-mass spectrometric analyses. We also found a reduction of protein tyrosine phosphorylation in sperm incubated under capacitating conditions from HCR. Interestingly, the addition of Protein Kinase A pathway activators -dibutyryl-cyclic AMP and iso-butylmethylxanthine- to the medium restored sperm capacitation. Finally, it was also reported a significant decrease in the percentage of reacted sperm in the presence of progesterone. In conclusion, our data showed that diet-induced hypercholesterolemia adversely affects semen quality and sperm motility, capacitation and acrosomal reaction in rabbits; probably due to an increase in cellular cholesterol content that alters membrane related events. PMID:20976152

  19. Sperm Trajectories Form Chiral Ribbons

    PubMed Central

    Su, Ting-Wei; Choi, Inkyum; Feng, Jiawen; Huang, Kalvin; McLeod, Euan; Ozcan, Aydogan

    2013-01-01

    We report the discovery of an entirely new three-dimensional (3D) swimming pattern observed in human and horse sperms. This motion is in the form of ‘chiral ribbons’, where the planar swing of the sperm head occurs on an osculating plane creating in some cases a helical ribbon and in some others a twisted ribbon. The latter, i.e., the twisted ribbon trajectory, also defines a minimal surface, exhibiting zero mean curvature for all the points on its surface. These chiral ribbon swimming patterns cannot be represented or understood by already known patterns of sperms or other micro-swimmers. The discovery of these unique patterns is enabled by holographic on-chip imaging of >33,700 sperm trajectories at >90–140 frames/sec, which revealed that only ~1.7% of human sperms exhibit chiral ribbons, whereas it increases to ~27.3% for horse sperms. These results might shed more light onto the statistics and biophysics of various micro-swimmers' 3D motion. PMID:23588811

  20. Cytometry of mammalian sperm

    SciTech Connect

    Gledhill, B.L.

    1983-10-11

    Male germ cells respond dramatically to a variety of insults and are important reproductive dosimeters. Semen analyses are very useful in studies on the effects of drugs, chemicals, and environmental hazards on testicular function, male fertility and heritable germinal mutations. The accessibility of male cells makes them well suited for analytical cytology. We might automate the process of determining sperm morphology but should not do so solely for increased speed. Rather, richer tangible benefits will derive from cytometric evaluation through increased sensitivity, reduced subjectivity, standardization between investigators and laboratories, enhanced archival systems, and the benefits of easily exchanged standardized data. Inroads on the standardization of assays for motility and functional integrity are being made. Flow cytometric analysis of total DNA content of individual sperm is an insensitive means to detect exposure to reproductive toxins because of the small size and low frequency of the DNA content errors. Flow cytometry can be applied to determine the proportions of X- and Y-sperm in semen samples.

  1. Mass-Specific Metabolic Rate and Sperm Competition Determine Sperm Size in Marsupial Mammals

    PubMed Central

    Tourmente, Maximiliano; Gomendio, Montserrat; Roldan, Eduardo R. S.

    2011-01-01

    Two complementary hypotheses have been proposed to explain variation in sperm size. The first proposes that post-copulatory sexual selection favors an increase in sperm size because it enhances sperm swimming speed, which is an important determinant of fertilization success in competitive contexts. The second hypothesis proposes that mass-specific metabolic rate acts as a constraint, because large animals with low mass-specific metabolic rates will not be able to process resources at the rates needed to produce large sperm. This constraint is expected to be particularly pronounced among mammals, given that this group contains some of the largest species on Earth. We tested these hypotheses among marsupials, a group in which mass-specific metabolic rates are roughly 30% lower than those of eutherian mammals of similar size, leading to the expectation that metabolic rate should be a major constraint. Our findings support both hypotheses because levels of sperm competition are associated with increases in sperm size, but low mass-specific metabolic rate constrains sperm size among large species. We also found that the relationship between sperm size and mass-specific metabolic rate is steeper among marsupials and shallower among eutherian mammals. This finding has two implications: marsupials respond to changes in mass-specific metabolic rate by modifying sperm length to a greater extent, suggesting that they are more constrained by metabolic rate. In addition, for any given mass-specific metabolic rate, marsupials produce longer sperm. We suggest that this is the consequence of marsupials diverting resources away from sperm numbers and into sperm size, due to their efficient sperm transport along the female tract and the existence of mechanisms to protect sperm. PMID:21731682

  2. Protein and carbohydrate intake influence sperm number and fertility in male cockroaches, but not sperm viability

    PubMed Central

    Bunning, Harriet; Rapkin, James; Belcher, Laurence; Archer, C. Ruth; Jensen, Kim; Hunt, John

    2015-01-01

    It is commonly assumed that because males produce many, tiny sperm, they are cheap to produce. Recent work, however, suggests that sperm production is not cost-free. If sperm are costly to produce, sperm number and/or viability should be influenced by diet, and this has been documented in numerous species. Yet few studies have examined the exact nutrients responsible for mediating these effects. Here, we quantify the effects of protein (P) and carbohydrate (C) intake on sperm number and viability in the cockroach Nauphoeta cinerea, as well as the consequences for male fertility. We found the intake of P and C influenced sperm number, being maximized at a high intake of diets with a P : C ratio of 1 : 2, but not sperm viability. The nutritional landscapes for male fertility and sperm number were closely aligned, suggesting that sperm number is the major determinant of male fertility in N. cinerea. Under dietary choice, males regulate nutrient intake at a P : C ratio of 1 : 4.95, which is midway between the ratios needed to maximize sperm production and pre-copulatory attractiveness in this species. This raises the possibility that males regulate nutrient intake to balance the trade-off between pre- and post-copulatory traits in this species. PMID:25608881

  3. Protein and carbohydrate intake influence sperm number and fertility in male cockroaches, but not sperm viability.

    PubMed

    Bunning, Harriet; Rapkin, James; Belcher, Laurence; Archer, C Ruth; Jensen, Kim; Hunt, John

    2015-03-01

    It is commonly assumed that because males produce many, tiny sperm, they are cheap to produce. Recent work, however, suggests that sperm production is not cost-free. If sperm are costly to produce, sperm number and/or viability should be influenced by diet, and this has been documented in numerous species. Yet few studies have examined the exact nutrients responsible for mediating these effects. Here, we quantify the effects of protein (P) and carbohydrate (C) intake on sperm number and viability in the cockroach Nauphoeta cinerea, as well as the consequences for male fertility. We found the intake of P and C influenced sperm number, being maximized at a high intake of diets with a P : C ratio of 1 : 2, but not sperm viability. The nutritional landscapes for male fertility and sperm number were closely aligned, suggesting that sperm number is the major determinant of male fertility in N. cinerea. Under dietary choice, males regulate nutrient intake at a P : C ratio of 1 : 4.95, which is midway between the ratios needed to maximize sperm production and pre-copulatory attractiveness in this species. This raises the possibility that males regulate nutrient intake to balance the trade-off between pre- and post-copulatory traits in this species. PMID:25608881

  4. Induced lipid peroxidation in ram sperm: semen profile, DNA fragmentation and antioxidant status.

    PubMed

    Hamilton, Thais Rose dos Santos; de Castro, Letícia Signori; Delgado, Juliana de Carvalho; de Assis, Patrícia Monken; Siqueira, Adriano Felipe Perez; Mendes, Camilla Mota; Goissis, Marcelo Demarchi; Muiño-Blanco, Teresa; Cebrián-Pérez, José Álvaro; Nichi, Marcílio; Visintin, José Antonio; D'Ávila Assumpção, Mayra Elena Ortiz

    2016-04-01

    Action of reactive oxygen species, protamination failures and apoptosis are considered the most important etiologies of sperm DNA fragmentation. This study evaluated the effects of induced lipid peroxidation susceptibility on native semen profile and identified the mechanisms involved in sperm DNA fragmentation and testicular antioxidant defense on Santa Ines ram sperm samples. Semen was collected from 12 adult rams (Ovis aries) performed weekly over a 9-week period. Sperm analysis (motility, mass motility, abnormalities, membrane and acrosome status, mitochondrial potential, DNA fragmentation, lipid peroxidation and intracellular free radicals production); protamine deficiency; PRM1, TNP1 and TNP2 gene expression; and determination of glutathione peroxidase (GPx), glutathione reductase, catalase (CAT) and superoxide dismutase activity and immunodetection in seminal plasma were performed. Samples were distributed into four groups according to the sperm susceptibility to lipid peroxidation after induction with ascorbate and ferrous sulfate (low, medium, high and very high). The results were analyzed by GLM test and post hoc least significant difference. We observed an increase in native GPx activity and CAT immunodetection in groups with high susceptibility to induced lipid peroxidation. We also found an increase in total sperm defects, acrosome and membrane damages in the group with the highest susceptibility to induced lipid peroxidation. Additionally, the low mitochondrial membrane potential, susceptible to chromatin fragmentation and the PRM1 mRNA were increased in the group showing higher susceptibility to lipid peroxidation. Ram sperm susceptibility to lipid peroxidation may compromise sperm quality and interfere with the oxidative homeostasis by oxidative stress, which may be the main cause of chromatin damage in ram sperm. PMID:26811546

  5. LONG-TERM EFFECTS OF TRIETHYLENEMELAMINE EXPOSURE ON MOUSE TESTIS CELLS AND SPERM CHROMATIN STRUCTURE ASSAYED BY FLOW CYTOMETRY

    EPA Science Inventory

    The toxic and potentially mutagenic actions of triethylenemelamine (TEM) on mouse body and testis weights, testicular cell kinetics, sperm production, sperm head morphology, and sperm chromatin structure were assessed in two experiments. he first experiment examined effects of fo...

  6. Backsurging perforations can increase production rates

    SciTech Connect

    Brieger, E.F.

    1991-07-01

    Subjecting formations to a large pressure differential or underbalance is a common means of surging perforations to remove damage and increase flow from oil and gas wells. Underbalanced perforating, a standard industry completion technique, is normally used to obtain the pressure differentials intended to dislodge debris from perforations and flush the surrounding compacted zone. Gradually applied pressure underbalance can be achieved by swabbing or jetting to reduce hydrostatic head. Suddenly applied underbalance is achieved by evacuating the tubing in conjunction with a rupture disc, tubing-conveyed perforating systems or by using a new wireline-set, through-tubing backsurge tool. These techniques, except for the through-tubing method, are often utilized only during later workovers due to the expense and difficulty of achieving an adequate underbalance. Many operators prefer to perforate in balanced or overbalanced pressures conditions. This typically leaves perforations completely or partially plugged with gun debris, mud solids and shattered formation material that has been recompacted. Production logging shows that wells often produce from only 10 to 20% of the total interval apparently because of ineffective, plugged perforations.

  7. Increasing efficiency in production of cloned piglets.

    PubMed

    Callesen, Henrik; Liu, Ying; Pedersen, Hanne S; Li, Rong; Schmidt, Mette

    2014-12-01

    The low efficiency in obtaining piglets after production of cloned embryos was challenged in two steps-first by performing in vitro culture for 5-6 days after cloning to obtain later-stage embryos for more precise selection for transfer, and second by reducing the number of embryos transferred per recipient sow. The data set consisted of combined results from a 4-year period where cloning was performed to produce piglets that were transgenic for important human diseases. For this, different transgenes and cell types were used, and the cloning work was performed by several persons using oocytes from different pig breeds, but following a standardized and optimized protocol. Results showed that in vitro culture is possible with a relatively stable rate of transferable embryos around 41% and a pregnancy rate around 90%. Furthermore, a reduction from around 80 embryos to 40 embryos transferred per recipient was possible without changing the efficiency of around 14% (piglets born out of embryos transferred). It was concluded that this approach can increase the efficiency in obtaining piglets by means of in vitro culture and selection of high-quality embryos with subsequent transfer into more recipients. Such changes can also reduce the need for personnel, time, and material when working with this technology. PMID:25333333

  8. Increasing the productivity of bioconversion processes

    SciTech Connect

    Chauhan, R.P.; Woodley, J.M.

    1997-06-01

    In some syntheses, product formation can cause problems that limit overall productivity. This is frequently the case in bioprocesses, especially in bioconversions, because the product may inhibit or damage the biological catalyst or interfere with other components in the reaction medium. Many reactions are reversible, so yields decrease when the product is allowed to accumulate in the reactor. Some desired products may be unstable or reactive under the conditions of the reaction. Any of these conditions can limit the maximum conversion or product concentration. However, many limitations can be overcome with in situ product removal (ISPR), a family of techniques in which the product is removed as it is synthesized. The authors have devised a systematic approach to identify the most suitable process options for the design and operation of bioconversion processes, emphasizing the integration of upstream (i.e., catalyst production) and downstream (i.e., product recovery) operations. The paper discusses separation principles, ISPR integration, choosing the best techniques, application of ISPR to bioconversion processes, and system design.

  9. Development of computer-assisted sperm analysis plugin for analyzing sperm motion in microfluidic environments using Image-J.

    PubMed

    Elsayed, Mohamed; El-Sherry, Taymour M; Abdelgawad, Mohamed

    2015-11-01

    We modified a previously reported computer-assisted sperm analysis (CASA) plugin for Image-J to enable analyzing motion of sperm cells in microfluidic environments. Microfluidics is increasingly being used in sperm-related applications such as sperm selection, IVF, and sperm motion behavior. Current CASA systems are not capable of analyzing motion of sperm cells in microfluidic devices where both sperm cells and the liquid itself are constantly moving, contrary to the conventional situation of sperm cells moving in a stationary liquid. We resolved this deficiency in the modified plugin reported here and built an image processing pipeline to enhance object detection, which increased CASA accuracy considerably. More importantly, particle tracking was improved and modified to accommodate sperm cells going out of focus for short periods during swimming on the same track. This last feature is particularly important in microfluidics where height of the microchannel is larger than that of CASA custom chambers to avoid channel blockage; this increased height causes sperm cells to frequently come in and out of focus. New parameters were introduced to allow studying new aspects of sperm motion behavior such as rheotaxis and wall tracking. The new plugin was able to detect and analyze motion of human, bull, and chicken sperm. A preliminary study using this tool agreed well with previously reported studies on rheotaxis and wall tracking behavior of sperm. PMID:26318232

  10. Use of penicillin and streptomycin to reduce spread of bacterial coldwater disease I: antibiotics in sperm extenders.

    PubMed

    Oplinger, Randall W; Wagner, Eric J

    2015-03-01

    Bacterial coldwater disease caused by Flavobacterium psychrophilum has led to the loss of significant numbers of hatchery-reared salmonids. The bacteria can be spread from parent to progeny within contaminated sperm and ovarian fluid. Methods for disinfecting ovarian fluid and unfertilized eggs are available, but methods for disinfecting sperm have not been described. In this study we determined whether sperm extenders containing a mixture of penicillin and streptomycin can be used to eliminate F. psychrophilum. In vitro trials demonstrated that when Rainbow Trout Oncorhynchus mykiss sperm is mixed with an extender, a 15-min exposure to 0.197 mg penicillin plus 0.313 mg/mL streptomycin is effective at killing the bacteria and has no effect on sperm motility. Small-scale trials showed that egg fertilization rates were not reduced when sperm held in an extender solution containing the same antibiotic mixture for 15 min was used to fertilize eggs. Production-scale trials, however, showed a roughly 18% decrease in egg fertilization rate when sperm stored in an antibiotic containing extender was used. To determine why a reduction in fertilization capacity was observed, a small-scale experiment testing the fertilization of eggs with larger quantities of sperm was performed and showed that increasing the volume of sperm used did not increase fertilization rates. Our results demonstrate that extenders containing penicillin and streptomycin can be used to disinfect sperm, especially when small quantities of eggs are fertilized, but factors negatively affecting egg fertilization and survival on a production scale still need further investigation. PMID:25581335

  11. Metabolism, sperm and fluid production of the isolated perfused testis of the sheep and goat

    PubMed Central

    Linzell, J. L.; Setchell, B. P.

    1969-01-01

    1. A total of nineteen ram and three goat testes have been perfused in isolation at 34-35° C for 3½-9 hr with heparinized blood and an added 5-HT antagonist (bromolysergic acid diethylamide) and their function compared with that of the normal ram testes in vivo. 2. The metabolism of the perfused testes and the testes in vivo was similar but blood flow through the perfused testes was two to three times normal. 3. Vasoconstriction was produced by adrenaline and noradrenaline (10-20 μg I.A.) and by electrical stimulation of nerves in the spermatic cord or of the lumbar sympathetic chain; these responses were abolished or reduced by phenoxybenzamine. 4. Flow of fluid from the rete testis continued only if ischaemia was reduced to a minimum and glucose concentration in the blood perfusing the testis was kept above about 25 mg/100 ml.; the fluid secreted during perfusion was of normal composition. 5. The perfused testis showed no evidence of autoregulation and the flow of fluid was not affected by changes in perfusion pressure. 6. When the temperature of three testes was raised to 40° C for 2 hr, metabolism increased but blood flow was unaltered; the flow of fluid and the concentration of spermatozoa decreased during heating. 7. The testes perfused at normal scrotal temperatures (34-35° C) were histologically normal but some abnormalities were observed in the heated testes. ImagesFig. 3Fig. 4 PMID:5773547

  12. Seasonal occurrence of sperm whales (Physeter macrocephalus) around Kelvin Seamount in the Sargasso Sea in relation to oceanographic processes

    NASA Astrophysics Data System (ADS)

    Wong, Sarah N. P.; Whitehead, Hal

    2014-09-01

    Sperm whales (Physeter macrocephalus) are widely distributed in all oceans, but they are clumped geographically, generally in areas associated with high primary and secondary productivity. The warm, clear waters of the Sargasso Sea are traditionally thought to be low in productivity, however recent surveys have found large numbers of sperm whales there. The New England Seamount Chain bisects the north-western portion of the Sargasso Sea, and might influence the mesoscale eddies associated with the Gulf Stream; creating areas of higher productivity within the Sargasso Sea. We investigated the seasonal occurrence of sperm whales over Kelvin Seamount (part of the New England Seamount Chain) and how it is influenced by oceanographic variables. An autonomous recording device was deployed over Kelvin Seamount from May to June 2006 and November 2006 to June 2007. A total of 6505 hourly two-minute recordings were examined for the presence of sperm whale echolocation clicks. Sperm whales were more prevalent around Kelvin in the spring (April to June: mean=51% of recordings contained clicks) compared to the winter (November to March: mean=16% of recordings contained clicks). Sperm whale prevalence at Kelvin was related to chlorophyll-a concentration four weeks previous, eddy kinetic energy and month. The mesoscale activity associated with the Gulf Stream and the Gulf Stream's interaction with the New England Seamount Chain likely play an important role in sperm whale occurrence in this area, by increasing productivity and perhaps concentration of cephalopod species.

  13. Turkey Sperm Reside in the Tubular Glands in the Urodeum Following Artificial Insemination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A turkey hen in egg production requires 48 hr after the last insemination to maximize the number of sperm in the uterovaginal junction sperm-storage tubules. Where the sperm that continue to fill the oviductal sperm-storage sites during this 48 hr period reside remains unknown. Histological sectio...

  14. Experimental evolution of sperm competitiveness in a mammal

    PubMed Central

    2011-01-01

    Background When females mate with multiple partners, sperm from rival males compete to fertilise the ova. Studies of experimental evolution have proven the selective action of sperm competition on male reproductive traits. However, while reproductive traits may evolve in response to sperm competition, this does not necessarily provide evidence that sperm competitive ability responds to selection. Indeed, a study of Drosophila failed to observe divergence in sperm competitive ability of males in lines selected for enhanced sperm offence and defence. Results Adopting the naturally polygamous house mouse (Mus domesticus) as our vertebrate model, we performed an experimental evolution study and observed genetic divergence in sperm quality; males from the polygamous selection lines produced ejaculates with increased sperm numbers and greater sperm motility compared to males from the monogamous lines. Here, after 12 generations of experimental evolution, we conducted competitive matings between males from lineages evolving under sperm competition and males from lineages subject to relaxed selection. We reduced variation in paternity arising from embryo mortality by genotyping embryos in utero at 14 days gestation. Our microsatellite data revealed a significant paternity bias toward males that evolved under the selective regime of sperm competition. Conclusion We provide evidence that the sperm competitiveness phenotype can respond to selection, and show that improved sperm quality translates to greater competitive fertilisation success in house mice. PMID:21251249

  15. Female choice of young sperm in a genetically monogamous bird.

    PubMed Central

    Wagner, Richard H; Helfenstein, Fabrice; Danchin, Etienne

    2004-01-01

    When females copulate with multiple males the potential exists for female sperm choice. Females may increase the probability of being fertilized by preferred males by selectively retaining their sperm while ejecting the sperm of unfavoured males. An alternative criterion to male quality for female sperm choice may be sperm age because old sperm degrade and can lead to zygote death or unhealthy offspring. Here, we report that in a genetically monogamous bird, the black-legged kittiwake Rissa tridactyla, females eject their mates' sperm according to when the copulations were performed. Following copulations that were performed approximately two weeks before egg laying, females ejected inseminations at high frequencies while retaining inseminations that occurred soon before laying. Females that suffered hatching failure had ejected sperm from early copulations less than half as frequently as females whose entire clutches hatched. Furthermore, chicks that hatched from eggs fertilized by old sperm were in poor condition relative to those fertilized by young sperm. These findings support the 'young sperm' hypothesis, which predicts that females choose fresh sperm to avoid reproductive failure and are the first to show intra-male sperm choice by females. PMID:15252964

  16. Antioxidant Effects of Brown Algae Sargassum on Sperm Parameters: CONSORT-Compliant Article.

    PubMed

    Sobhani, Alireza; Eftekhaari, Tasnim Eghbal; Shahrzad, Mohammad Esmaeil; Natami, Mohammad; Fallahi, Soghra

    2015-12-01

    The occurrence of oxidative stress during the sperm freeze-thaw cycles affects the sperm parameters and eventually leads to a decrease in its reproductive potential. Sperm protection against oxidative reactions during freezing is done by antioxidants. Since the selection of a suitable sperm cryopreservation bank is effective in maintaining acceptable reproductive potential and motility of sperm during cryopreservation.This study aimed to evaluate the antioxidant effects of different doses of the extract of brown algae Sargassum on oxidative stress and frozen human sperm parameters.We conducted a randomized controlled trial on the semen samples from 11 healthy men in the age group of 25 to 36 years. The samples were collected by masturbation after 3 to 5 days of abstinence from ejaculation. The specimens were divided into 3 equal parts, including 1 control group and 2 experimental groups.The 2 experimental groups were frozen using the rapid solidification technique with Sargassum extract at doses of 250 and 500 μg/mL.Motility and morphology of sperms were measured using a computer system and CASA software and the amount of reactive oxygen species was determined using Oxisperm kit.Sargassum extract significantly decreased the amount of reactive oxygen species (P < 0.005) and at doses of 250 and 500 μg/mL, significantly increased the overall motility (P < 0.006) and progressive motility (P < 0.007) after solidification, but did not affect the normal morphology of sperms.The addition of ethanol extract of Sargassum prevents reactive oxygen species production during the solidification process and improves sperm motility at doses of 250 and 500 μg/mL. PMID:26717354

  17. Consequences of autoimmunity to sperm antigens in vasectomized men.

    PubMed

    Anderson, D J; Alexander, N J

    1979-12-01

    The development by a large percentage of vasectomized men of sperm autoantibodies is discussed in this monograph chapter. The production of anti-sperm antibodies is attributed to: 1) granuloma formation; 2) increased permeability of epithelial barriers in the rete testis and epididymis; and 3) transport of phagocytic cells to regional lymph nodes. Individual variation in type of antibodies and response to antibody production is documented and is thought to depend on such factors as rate of sperm production, the structure of the blood-testis barrier, surgical technique, and expression of immune response genes. Morphological changes in spermatozoa and testes occurring after vasectomy may be induced by immunological mechanisms. Tests of cell-mediated immunity to sperm antigens are described, and more accurate tests are needed. Animal studies provide evidence that chronic immune stimulation can result in formation of circulating immune complexes, resulting in deleterious systemic effects, including damage to kidneys, blood vessels, and cells of the immune system. Further studies of the autoimmune orchitis phenomenon may aid in avoidance of immunologically mediated side effects of vasectomy. PMID:92384

  18. Intracytoplasmic Sperm Injection (ICSI)

    MedlinePlus

    ... male partner produces too few sperm to do artificial insemination (intrauterine insemination [IUI]) or IVF. • The sperm may ... birth defects may actually be due to the infertility and not the treatments used to overcome the ...

  19. Development of a Selection Index on Blue Catfish for Optimized Sperm Production in the Catfish X Blue Hybrid Catfish Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Channel x blue hybrid catfish is a phenomenal fish for pond culture. This fish represents a major improvement in catfish production efficiency due to higher growth rates, lower feed conversion efficiency and improved disease resistance and processing yield compared to the commonly raised channel ca...

  20. Fertilization of C57BL/6 mouse sperm collected from cauda epididymides after preservation or transportation at 4 degrees C using laser-microdissected oocytes.

    PubMed

    Kaneko, Takehito; Fukumoto, Kiyoko; Haruguchi, Yukie; Kondo, Tomoko; Machida, Hiromi; Koga, Mika; Nakagawa, Yoshiko; Tsuchiyama, Shuuji; Saiki, Kiyora; Noshiba, Shiho; Nakagata, Naomi

    2009-08-01

    The C57BL/6 mouse is commonly used to produce transgenic and knockout strains for biomedical research. However, the motility and fertility of its sperm decrease markedly with freezing. Short-term preservation of sperm without freezing can avoid this. Furthermore, such samples can be transported safety without the special skills or equipment needed for the transportation of live animals or frozen products. We evaluated the motility and fertility of sperm collected from cauda epididymides after preservation or transportation at 4 degrees C. Oocytes with the zona pellucida subjected to laser-microdissection were used to assist fertilization in vitro. Although the motility of sperm gradually decreased with storage (P<0.05), no disruption of the sperm plasma membrane was seen. The proportion of zona-intact oocytes fertilized with sperm preserved for 0, 24, 48 and 72h were 70, 14, 5 and 1%, respectively. On the other hand, 45, 20 and 14% of laser-microdissected oocytes were fertilized by sperm preserved for 24, 48 and 72h, respectively (P<0.05). The fertility of sperm collected from cauda epididymides of two transgenic strains after transportation at 4 degrees C were also significantly increased using laser-microdissected oocytes rather than zona-intact oocytes (57 and 68% vs. 5%, P<0.05). Efficient production of offspring from sperm preserved or transported at 4 degrees C was achieved using laser-microdissected oocytes. Thus the fertility of sperm preserved or transported at 4 degrees C could be maintained, although motility gradually decreased with storage. Laser-microdissected oocytes will contribute to the efficient production of embryos and offspring using such preserved sperm samples. PMID:19394323

  1. Flow cytometry of sperm

    SciTech Connect

    Gledhill, B.L.

    1987-09-21

    This brief paper summarizes automated flow cytometric determination of sperm morphology and flow cytometry/sorting of sperm with application to sex preselection. In the latter context, mention is made of results of karyotypic determination of sex chromosome ratios in albumin-processed human sperm. 23 refs., 1 fig., 1 tab.

  2. Regulation of axonemal motility in demembranated equine sperm.

    PubMed

    Loux, Shavahn C; Macías-Garcia, Beatríz; González-Fernández, Lauro; Canesin, Heloisa DeSiqueira; Varner, Dickson D; Hinrichs, Katrin

    2014-12-01

    Equine in vitro fertilization is not yet successful because equine sperm do not effectively capacitate in vitro. Results of previous studies suggest that this may be due to failure of induction of hyperactivated motility in equine sperm under standard capacitating conditions. To evaluate factors directly affecting axonemal motility in equine sperm, we developed a demembranated sperm model and analyzed motility parameters in this model under different conditions using computer-assisted sperm analysis. Treatment of ejaculated equine sperm with 0.02% Triton X-100 for 30 sec maximized both permeabilization and total motility after reactivation. The presence of ATP was required for motility of demembranated sperm after reactivation, but cAMP was not. The calculated intracellular pH of intact equine sperm was 7.14 ± 0.07. Demembranated sperm showed maximal total motility at pH 7. Neither increasing pH nor increasing calcium levels, nor any interaction of the two, induced hyperactivated motility in demembranated equine sperm. Motility of demembranated sperm was maintained at free calcium concentrations as low as 27 pM, and calcium arrested sperm motility at much lower concentrations than those reported in other species. Calcium arrest of sperm motility was not accompanied by flagellar curvature, suggesting a failure of calcium to induce the tonic bend seen in other species and thought to support hyperactivated motility. This indicated an absence, or difference in calcium sensitivity, of the related asymmetric doublet-sliding proteins. These studies show a difference in response to calcium of the equine sperm axoneme to that reported in other species that may be related to the failure of equine sperm to penetrate oocytes in vitro under standard capacitating conditions. Further work is needed to determine the factors that stimulate hyperactivated motility at the axonemal level in equine sperm. PMID:25339104

  3. Effects of the Czech Propolis on Sperm Mitochondrial Function

    PubMed Central

    Cedikova, Miroslava; Miklikova, Michaela; Stachova, Lenka; Grundmanova, Martina; Tuma, Zdenek; Vetvicka, Vaclav; Zech, Nicolas; Kralickova, Milena; Kuncova, Jitka

    2014-01-01

    Propolis is a natural product that honeybees collect from various plants. It is known for its beneficial pharmacological effects. The aim of our study was to evaluate the impact of propolis on human sperm motility, mitochondrial respiratory activity, and membrane potential. Semen samples from 10 normozoospermic donors were processed according to the World Health Organization criteria. Propolis effects on the sperm motility and mitochondrial activity parameters were tested in the fresh ejaculate and purified spermatozoa. Propolis preserved progressive motility of spermatozoa in the native semen samples. Oxygen consumption determined in purified permeabilized spermatozoa by high-resolution respirometry in the presence of adenosine diphosphate and substrates of complex I and complex II (state OXPHOSI+II) was significantly increased in the propolis-treated samples. Propolis also increased uncoupled respiration in the presence of rotenone (state ETSII) and complex IV activity, but it did not influence state LEAK induced by oligomycin. Mitochondrial membrane potential was not affected by propolis. This study demonstrates that propolis maintains sperm motility in the native ejaculates and increases activities of mitochondrial respiratory complexes II and IV without affecting mitochondrial membrane potential. The data suggest that propolis improves the total mitochondrial respiratory efficiency in the human spermatozoa in vitro thereby having potential to improve sperm motility. PMID:25104965

  4. Turbidity as a method of preparing sperm dilutions in the echinoid sperm/egg bioassay

    SciTech Connect

    Hall, T.J.; Haley, R.K.; Battan, K.J. )

    1993-11-01

    The use of turbidimeter for preparing sperm dilutions used in the echinoid sperm/egg bioassay was evaluated. Regression analyses of the relationship between sperm density and turbidity for the sea urchins Strongylocentrotus purpuratus and Strongylocentrotus droebachiensis and the sand dollar Dendraster excentricus indicated that although there were slope differences for each species, each coefficient of determination was highly significant. For Dendraster excentricus, triplicate hemacytometer counts over a range of turbidities as well as repeated preparations of a single sperm turbidity indicated similar variability for each. The use of the turbidimeter has time-saving advantages over conventional hemacytometer methods without sacrificing precision. Sperm dilutions can be prepared rapidly, minimizing seawater sperm preactivation before test initiation, and may therefore contribute to increased test precision.

  5. Effects of photobiomodulation therapy (PBMT) on bovine sperm function.

    PubMed

    Siqueira, Adriano F P; Maria, Fernanda S; Mendes, Camilla M; Hamilton, Thais R S; Dalmazzo, Andressa; Dreyer, Thiago R; da Silva, Herculano M; Nichi, Marcilio; Milazzotto, Marcella P; Visintin, José A; Assumpção, Mayra E O A

    2016-08-01

    Fertilization rates and subsequent embryo development rely on sperm factors related to semen quality and viability. Photobiomodulation therapy (PBMT) is based on emission of electromagnetic waves of a laser optical system that interact with cells and tissues resulting in biological effects. This interaction is mediated by photoacceptors that absorb the electromagnetic energy. Effects are dependent of irradiation parameters, target cell type, and species. In sperm, PBMT improves several features like motility and viability, affecting sperm aerobic metabolism and energy production. The aim of this study was to investigate, under same conditions, how different output powers (5, 7.5, and 10 mW) and time of irradiation (5 and 10 min) of laser (He-Ne laser, 633 nm) may affect frozen/thawed bovine sperm functions. Results showed significant effects depending on power while using 10 min of irradiation on motility parameters and mitochondrial potential. However, no effect was observed using 5 min of irradiation, regardless of power applied. In conclusion, PBMT is effective to modulate bovine sperm function. The effectiveness is dependent on the interaction between power applied and duration of irradiation, showing that these two parameters simultaneously influence sperm function. In this context, when using the same fluency and energy with different combinations of power and time of exposure, we observed distinct effects, revealing that biological effects should be also based on simple parameters rather than only composite parameters such as fluency, irradiance and energy. Laser irradiation of frozen/thawed bovine semen led to an increase on mitochondrial function and motility parameters that could potentially improve fertility rates. PMID:27272676

  6. Detection of structural and numerical chomosomal abnormalities by ACM-FISH analysis in sperm of oligozoospermic infertility patients

    SciTech Connect

    Schmid, T E; Brinkworth, M H; Hill, F; Sloter, E; Kamischke, A; Marchetti, F; Nieschlag, E; Wyrobek, A J

    2003-11-10

    Modern reproductive technologies are enabling the treatment of infertile men with severe disturbances of spermatogenesis. The possibility of elevated frequencies of genetically and chromosomally defective sperm has become an issue of concern with the increased usage of intracytoplasmic sperm injection (ICSI), which can enable men with severely impaired sperm production to father children. Several papers have been published about aneuploidy in oligozoospermic patients, but relatively little is known about chromosome structural aberrations in the sperm of these patients. We examined sperm from infertile, oligozoospermic individuals for structural and numerical chromosomal abnormalities using a multicolor ACM FISH assay that utilizes DNA probes specific for three regions of chromosome 1 to detect human sperm that carry numerical chromosomal abnormalities plus two categories of structural aberrations: duplications and deletions of 1pter and 1cen, and chromosomal breaks within the 1cen-1q12 region. There was a significant increase in the average frequencies of sperm with duplications and deletions in the infertility patients compared with the healthy concurrent controls. There was also a significantly elevated level of breaks within the 1cen-1q12 region. There was no evidence for an increase in chromosome-1 disomy, or in diploidy. Our data reveal that oligozoospermia is associated with chromosomal structural abnormalities suggesting that, oligozoospermic men carry a higher burden of transmissible, chromosome damage. The findings raise the possibility of elevated levels of transmissible chromosomal defects following ICSI treatment.

  7. Coal liquefaction to increase jet fuel production

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Processing concept that increases supply of jet fuel has been developed as part of study on methods for converting coal to hydrogen, methane, and jet fuel. Concept takes advantage of high aromatic content of coal-derived liquids to make high-octane gasoline, instead of destroying aromatics to make jet fuel.

  8. Sensors Increase Productivity in Harsh Environments

    NASA Technical Reports Server (NTRS)

    2008-01-01

    California's San Juan Capistrano-based Endevco Corporation licensed three patents covering high-temperature, harsh-environment silicon carbide (Si-C) pressure sensors from Glenn Research Center. The company is exploring their use in government markets, as well as in commercial markets, including commercial jet testing, deep well drilling applications where pressure and temperature increase with drilling depth, and in automobile combustion chambers.

  9. Predominance of sperm motion in corners

    PubMed Central

    Nosrati, Reza; Graham, Percival J.; Liu, Qiaozhi; Sinton, David

    2016-01-01

    Sperm migration through the female tract is crucial to fertilization, but the role of the complex and confined structure of the fallopian tube in sperm guidance remains unknown. Here, by confocal imaging microchannels head-on, we distinguish corner- vs. wall- vs. bulk-swimming bull sperm in confined geometries. Corner-swimming dominates with local areal concentrations as high as 200-fold that of the bulk. The relative degree of corner-swimming is strongest in small channels, decreases with increasing channel size, and plateaus for channels above 200 μm. Corner-swimming remains predominant across the physiologically-relevant range of viscosity and pH. Together, boundary-following sperm account for over 95% of the sperm distribution in small rectangular channels, which is similar to the percentage of wall swimmers in circular channels of similar size. We also demonstrate that wall-swimming sperm travel closer to walls in smaller channels (~100 μm), where the opposite wall is within the hydrodynamic interaction length-scale. The corner accumulation effect is more than the superposition of the influence of two walls, and over 5-fold stronger than that of a single wall. These findings suggest that folds and corners are dominant in sperm migration in the narrow (sub-mm) lumen of the fallopian tube and microchannel-based sperm selection devices. PMID:27211846

  10. Predominance of sperm motion in corners.

    PubMed

    Nosrati, Reza; Graham, Percival J; Liu, Qiaozhi; Sinton, David

    2016-01-01

    Sperm migration through the female tract is crucial to fertilization, but the role of the complex and confined structure of the fallopian tube in sperm guidance remains unknown. Here, by confocal imaging microchannels head-on, we distinguish corner- vs. wall- vs. bulk-swimming bull sperm in confined geometries. Corner-swimming dominates with local areal concentrations as high as 200-fold that of the bulk. The relative degree of corner-swimming is strongest in small channels, decreases with increasing channel size, and plateaus for channels above 200 μm. Corner-swimming remains predominant across the physiologically-relevant range of viscosity and pH. Together, boundary-following sperm account for over 95% of the sperm distribution in small rectangular channels, which is similar to the percentage of wall swimmers in circular channels of similar size. We also demonstrate that wall-swimming sperm travel closer to walls in smaller channels (~100 μm), where the opposite wall is within the hydrodynamic interaction length-scale. The corner accumulation effect is more than the superposition of the influence of two walls, and over 5-fold stronger than that of a single wall. These findings suggest that folds and corners are dominant in sperm migration in the narrow (sub-mm) lumen of the fallopian tube and microchannel-based sperm selection devices. PMID:27211846

  11. Predominance of sperm motion in corners

    NASA Astrophysics Data System (ADS)

    Nosrati, Reza; Graham, Percival J.; Liu, Qiaozhi; Sinton, David

    2016-05-01

    Sperm migration through the female tract is crucial to fertilization, but the role of the complex and confined structure of the fallopian tube in sperm guidance remains unknown. Here, by confocal imaging microchannels head-on, we distinguish corner- vs. wall- vs. bulk-swimming bull sperm in confined geometries. Corner-swimming dominates with local areal concentrations as high as 200-fold that of the bulk. The relative degree of corner-swimming is strongest in small channels, decreases with increasing channel size, and plateaus for channels above 200 μm. Corner-swimming remains predominant across the physiologically-relevant range of viscosity and pH. Together, boundary-following sperm account for over 95% of the sperm distribution in small rectangular channels, which is similar to the percentage of wall swimmers in circular channels of similar size. We also demonstrate that wall-swimming sperm travel closer to walls in smaller channels (~100 μm), where the opposite wall is within the hydrodynamic interaction length-scale. The corner accumulation effect is more than the superposition of the influence of two walls, and over 5-fold stronger than that of a single wall. These findings suggest that folds and corners are dominant in sperm migration in the narrow (sub-mm) lumen of the fallopian tube and microchannel-based sperm selection devices.

  12. Age-dependent changes in sperm production, semen quality, and testicular volume in the black-footed ferret (Mustela nigripes).

    PubMed

    Wolf, K N; Wildt, D E; Vargas, A; Marinari, P E; Kreeger, J S; Ottinger, M A; Howard, J G

    2000-07-01

    The black-footed ferret (Mustela nigripes), which was extirpated from its native North American prairie habitat during the 1980s, is being reintroduced to the wild because of a successful captive-breeding program. To enhance propagation, the reproductive biology of this endangered species is being studied intensively. The typical life span of the black-footed ferret is approximately 7 yr. Female fecundity declines after 3 yr of age, but the influence of age on male reproduction is unknown. In this study, testis volume, seminal traits, sperm morphology, and serum testosterone were compared in 116 males from 1 to 7 yr of age living in captivity. Results demonstrated that testes volume during the peak breeding season was similar (P > 0.05) among males 1 to 5 yr of age, reduced (P < 0.05) among males 6 yr of age, and further reduced (P < 0.05) among males 7 yr of age. Motile sperm/ejaculate was similar in males 1 to 6 yr of age but diminished (P < 0.05) in those 7 yr of age. Males at 6 and 7 yr of age produced fewer (P < 0.05) structurally normal sperm than younger counterparts; however, serum testosterone concentrations were not reduced (P > 0.05) in older males. Histological comparison of testicular/epididymal tissue from 5- and 7-yr-old black-footed ferrets confirmed that the interval between these two ages may represent a transitional period to reproductive senescence. In summary, functional reproductive capacity of male black-footed ferrets exceeds that of females by at least 2 yr. Testes and seminal quality are indistinguishable among males 1 to 5 yr of age, with progressive reproductive aging occurring thereafter. PMID:10859258

  13. Increasing Efficiency in Photoelectrochemical Hydrogen Production

    SciTech Connect

    Warren, S.; Turner, J.

    2002-01-01

    Photoelectrochemical hydrogen production promises to be a renewable, clean, and efficient way of storing the sun's energy for use in hydrogen-powered fuel cells. We use p-type Ga.51In.49P semiconductor (henceforth as GaInP2) to absorb solar energy and produce a photocurrent. When the semiconductor is immersed in water, the photocurrent can break down water into hydrogen and oxygen. However, before the GaInP2 can produce hydrogen and oxygen, the conduction band and the Fermi level of the semiconductor must overlap the water redox potentials. In an unmodified system, the conduction band and Fermi level of GaInP2 do not overlap the water redox potentials. When light shines on the semiconductor, electrons build up on the surface, shifting the bandedges and Fermi level further away from overlap of the water redox potentials. We report on surface treatments with metallated porphyrins and transition metals that suppress bandedge migration and allow bandedge overlap to occur. Coating ruthenium octaethylporphyrin carbonyl (RuOEP CO) on the GaInP2 surface shifted bandedges in the positive direction by 270 mV on average, allowing the bandedges to frequently overlap the water redox potentials. Coating the GaInP2 surface with RuCl3 catalyzed charge transfer from the semiconductor to the water, lessening bandedge migration under light irradiation. Future work will focus on the long-term surface stability of these new treatments and quantitative applications of porphyrins.

  14. Ovarian fluid of receptive females enhances sperm velocity

    NASA Astrophysics Data System (ADS)

    Gasparini, Clelia; Andreatta, Gabriele; Pilastro, Andrea

    2012-05-01

    The females of several internal fertilizers are able to store sperm for a long time, reducing the risk of sperm limitation. However, it also means that males can attempt to mate outside females' receptive period, potentially increasing the level of sperm competition and exacerbating sexual conflict over mating. The guppy ( Poecilia reticulata), an internally fertilizing fish, is a model system of such competition and conflict. Female guppies accept courtship and mate consensually only during receptive periods of the ovarian cycle but receive approximately one (mostly forced) mating attempt per minute both during and outside their sexually receptive phase. In addition, females can store viable sperm for months. We expected that guppy females would disfavour sperm received during their unreceptive period, possibly by modulating the quality and/or quantity of the components present in the ovarian fluid (OF) over the breeding cycle. Ovarian fluid has been shown to affect sperm velocity, a determinant of sperm competition success in this and other fishes. We found that in vitro sperm velocity is slower in OF collected from unreceptive females than in OF from receptive females. Visual stimulation with a potential partner prior to collection did not significantly affect in vitro sperm velocity. These results suggest that sperm received by unreceptive females may be disfavoured as sperm velocity likely affects the migration process and the number of sperm that reach storage sites.

  15. Drosophila Sperm Motility in the Reproductive Tract1

    PubMed Central

    Yang, Yong; Lu, Xiangyi

    2011-01-01

    Motile cilia and flagella exhibit many waveforms as outputs of dynein activation sequences on the highly conserved axoneme. Motility change of sperm in the reproductive tract is difficult to study and remains an important area of investigation. Sperm typically execute a sinusoidal waveform. Increased viscosity in the medium induces somewhat unusual arc-line and helical waveforms in some sperm. However, whether the latter two waveforms occur in vivo is not known. Using green fluorescence protein imaging, we show that Drosophila sperm in the uterus move in circular foci via arc-line waves, predominantly in a tail-leading orientation. From the uterus, a small fraction of the sperm enters the seminal receptacle (SR) in parallel formations. After sperm storage and coincident with fertilization of the egg, the sperm exit the SR via head-leading helical waves. Consistent with the observed bidirectional movements, the sperm show the ability to propagate both base-to-tip and tip-to-base flagellar waves. Numerous studies have shown that sperm motility is regulated by intraflagellar calcium concentrations; in particular, the Pkd2 calcium channel has been shown to affect sperm storage. Our analyses here suggest that Pkd2 is required for the sperm to adopt the correct waveform and movement orientation during SR entry. A working model for the sperm's SR entry movement is proposed. PMID:21293028

  16. Ovarian fluid of receptive females enhances sperm velocity.

    PubMed

    Gasparini, Clelia; Andreatta, Gabriele; Pilastro, Andrea

    2012-05-01

    The females of several internal fertilizers are able to store sperm for a long time, reducing the risk of sperm limitation. However, it also means that males can attempt to mate outside females' receptive period, potentially increasing the level of sperm competition and exacerbating sexual conflict over mating. The guppy (Poecilia reticulata), an internally fertilizing fish, is a model system of such competition and conflict. Female guppies accept courtship and mate consensually only during receptive periods of the ovarian cycle but receive approximately one (mostly forced) mating attempt per minute both during and outside their sexually receptive phase. In addition, females can store viable sperm for months. We expected that guppy females would disfavour sperm received during their unreceptive period, possibly by modulating the quality and/or quantity of the components present in the ovarian fluid (OF) over the breeding cycle. Ovarian fluid has been shown to affect sperm velocity, a determinant of sperm competition success in this and other fishes. We found that in vitro sperm velocity is slower in OF collected from unreceptive females than in OF from receptive females. Visual stimulation with a potential partner prior to collection did not significantly affect in vitro sperm velocity. These results suggest that sperm received by unreceptive females may be disfavoured as sperm velocity likely affects the migration process and the number of sperm that reach storage sites. PMID:22430815

  17. Region-wide impairment of Atlantic croaker testicular development and sperm production in the northern Gulf of Mexico hypoxic dead zone.

    PubMed

    Thomas, Peter; Rahman, Md Saydur

    2010-01-01

    Recently evidence has been obtained for reproductive impairment in estuarine populations of Atlantic croaker exposed to seasonal hypoxia. However, it is not known whether a similar disruption of reproductive function occurs in croaker inhabiting a much larger hypoxic area, the extensive dead zone in coastal regions of the northern Gulf of Mexico extending from the Mississippi Delta to East Texas. Gonadal development in male Atlantic croaker collected in September 2008 at six sites in the dead zone was compared to that in male fish sampled from three reference sites east of the Mississippi Delta which do not experience persistent hypoxia. Croaker testes collected from the dead zone were at an earlier stage of spermatogenesis than those from the reference sites. Histological examination of the testes collected from the dead zone showed that their tubules had small lumens that contained very little sperm compared to the lumens of the reference fish. Overall, sperm production was 26.2% that of the control fish at the reference sites. This decrease in spermatogenesis at the dead zone sites was accompanied by an approximately 50% decrease in testicular growth compared to that in the reference fish. The results suggest that reproductive impairment can occur over regional scales in marine fish populations exposed to extensive seasonal hypoxia in dead zones with potential long-term impacts on population abundance. PMID:19931178

  18. Sperm macromolecules associated with bull fertility.

    PubMed

    Kaya, Abdullah; Memili, Erdoğan

    2016-06-01

    Bull fertility, ability of the sperm to fertilize and activate the egg that sustain embryo development, is vitally important for effective and efficient production of cattle. Fertility is a complex trait with low heritability. Despite recent advances in genomic selection and possibility of enormous paternal benefits to profitable cattle production, there exist no reliable tests for evaluating semen quality and predicting bull fertility. This review focuses on sperm macromolecules such as transcripts, proteins and the epigenome, i.e., the functional genome that are associated with bull fertility. Generating new information in these systems is important beyond agriculture because such progress advances the fundamental science of the mammalian male gamete while at the same time introduces biotechnology into livestock production. Sperm macromolecules and epigenome markers associated with bull fertility can be used alone or in combination with the current SNP microarrays to determine sperm quality and to indicate bull fertility. PMID:26925808

  19. Sperm selection and genetic incompatibility: does relatedness of mates affect male success in sperm competition?

    PubMed Central

    Stockley, P.

    1999-01-01

    Sperm selection may be said to occur if females influence the relative success of ejaculates competing to fertilize their ova. Most evidence that female animals or their ova are capable of sperm selection relates to male genetic incompatibility, although relatively few studies focus on competition between conspecific males. Here I look for evidence of sperm selection with respect to relatedness of mates. Reduced fitness or inbreeding effects in offspring resulting from copulations between close relatives are well documented. If females are capable of sperm selection, they might therefore be expected to discriminate against the sperm of sibling males during sperm competition. I describe an experimental protocol designed to test for evidence of sperm selection while controlling for inbreeding effects. Using decorated field crickets (Gryllodes supplicans), I found that sibling males achieved lower fertilization success in competition with a male unrelated to the female than in competition with another sibling more frequently than expected by chance, although the mean paternity values did not differ significantly between treatments. The tendancy for sibling males to achieve relatively lower fertilization success in competition with males unrelated to the female could not be explained by the effects of increased ejaculate allocation, female control of sperm transfer or inbreeding. This study therefore provides some evidence in support of the idea that female insects (or their ova) may be capable of selection against sperm on the basis of genetic similarity of conspecific males.

  20. Increasing Labour Productivity in Agriculture and Its Implications

    ERIC Educational Resources Information Center

    van den Ban, Anne

    2011-01-01

    In order to profit from the economic growth in their society farmers can (1) increase the yields of their crops and animals, (2) switch to the production of high value products for which there is an increasing demand in the market, (3) increase the labour productivity on their farm, (4) find non-farm sources of income for some or all of their…

  1. Melatonin intake since weaning ameliorates steroidogenic function and sperm motility of streptozotocin-induced diabetic rats.

    PubMed

    da Costa, C F P; Gobbo, M G; Taboga, S R; Pinto-Fochi, M E; Góes, R M

    2016-05-01

    Melatonin may be used as an antioxidant in therapy against systemic sequelae caused by oxidative stress in diabetes. However, as melatonin has a major role in regulating reproductive activity, its consequence on reproductive parameters under diabetes needs to be better clarified. We have studied whether prior and concomitant treatment of juvenile Wistar rats with low doses of melatonin interferes in reproductive damage induced by experimental diabetes after 1 and 8 weeks. The consequences of melatonin administration since weaning on reproductive parameters of healthy rats at adulthood were also evaluated. Melatonin was provided in drinking water (10 μg/kg b.w./day) after weaning (5-week-old). Diabetes was induced by streptozotocin injection (4.5 mg/100 g b.w.) at 13-week-old rats, and rats were euthanized 1 and 8 weeks after disease onset. Diabetes decreased circulating testosterone levels (~35% to 1 week; ~62% to 2 months; p < 0.01) but did not affect testes sperm counts. Two months of diabetes reduced the sperm reserve and led to atrophy of epididymal cauda. Both 1-week and 2-month diabetes impaired sperm motility, decreased the number of spermatozoa with progressive movement, and increased the number of immotile sperm. Melatonin intake reduced serum testosterone levels ~29% in healthy 14-week-old and ~23% in 21-week-old rats and reduced daily testicular sperm production ~26% in the latter disease stage, but did not interfere in sperm reserves and transit time for both experimental periods. Exogenous melatonin prevented the serum testosterone decrease and damage to sperm motility in diabetic rats and attenuated reduction in sperm counts and transit time induced by 1-week diabetes but did not avoid this decrease at 2-month diabetes. Low doses of melatonin administered prior to and during experimental diabetes attenuated damage to testicular steroidogenic activity and preserved sperm motility, but not sperm reserves in the rat. Our data indicated a

  2. Sperm morphology, adenosine triphosphate (ATP) concentration and swimming velocity: unexpected relationships in a passerine bird

    PubMed Central

    Bennison, Clair; Brookes, Lola; Slate, Jon; Birkhead, Tim

    2016-01-01

    The relationship between sperm energetics and sperm function is poorly known, but is central to our understanding of the evolution of sperm traits. The aim of this study was to examine how sperm morphology and ATP content affect sperm swimming velocity in the zebra finch Taeniopygia guttata. We exploited the high inter-male variation in this species and created extra experimental power by increasing the number of individuals with very long or short sperm through artificial selection. We found a pronounced quadratic relationship between total sperm length and swimming velocity, with velocity increasing with length up to a point, but declining in the very longest sperm. We also found an unexpected negative association between midpiece length and ATP content: sperm with a short midpiece generally contained the highest concentration of ATP. Low intracellular ATP is therefore unlikely to explain reduced swimming velocity among the very longest sperm (which tend to have a shorter midpiece). PMID:27559067

  3. Sperm morphology, adenosine triphosphate (ATP) concentration and swimming velocity: unexpected relationships in a passerine bird.

    PubMed

    Bennison, Clair; Hemmings, Nicola; Brookes, Lola; Slate, Jon; Birkhead, Tim

    2016-08-31

    The relationship between sperm energetics and sperm function is poorly known, but is central to our understanding of the evolution of sperm traits. The aim of this study was to examine how sperm morphology and ATP content affect sperm swimming velocity in the zebra finch Taeniopygia guttata We exploited the high inter-male variation in this species and created extra experimental power by increasing the number of individuals with very long or short sperm through artificial selection. We found a pronounced quadratic relationship between total sperm length and swimming velocity, with velocity increasing with length up to a point, but declining in the very longest sperm. We also found an unexpected negative association between midpiece length and ATP content: sperm with a short midpiece generally contained the highest concentration of ATP. Low intracellular ATP is therefore unlikely to explain reduced swimming velocity among the very longest sperm (which tend to have a shorter midpiece). PMID:27559067

  4. The dynamics of sperm cooperation in a competitive environment

    PubMed Central

    Fisher, Heidi S.; Giomi, Luca; Hoekstra, Hopi E.; Mahadevan, L.

    2014-01-01

    Sperm cooperation has evolved in a variety of taxa and is often considered a response to sperm competition, yet the benefit of this form of collective movement remains unclear. Here, we use fine-scale imaging and a minimal mathematical model to study sperm aggregation in the rodent genus Peromyscus. We demonstrate that as the number of sperm cells in an aggregate increase, the group moves with more persistent linearity but without increasing speed. This benefit, however, is offset in larger aggregates as the geometry of the group forces sperm to swim against one another. The result is a non-monotonic relationship between aggregate size and average velocity with both a theoretically predicted and empirically observed optimum of six to seven sperm per aggregate. To understand the role of sexual selection in driving these sperm group dynamics, we compared two sister-species with divergent mating systems. We find that sperm of Peromyscus maniculatus (highly promiscuous), which have evolved under intense competition, form optimal-sized aggregates more often than sperm of Peromyscus polionotus (strictly monogamous), which lack competition. Our combined mathematical and experimental study of coordinated sperm movement reveals the importance of geometry, motion and group size on sperm velocity and suggests how these physical variables interact with evolutionary selective pressures to regulate cooperation in competitive environments. PMID:25056618

  5. Dynamics of heparin-binding proteins on boar sperm.

    PubMed

    Dapino, Dora G; Teijeiro, Juan M; Cabada, Marcelo O; Marini, Patricia E

    2009-12-01

    The presence, topology and dynamics of heparin-binding proteins (HBP) on boar sperm were evaluated. HBP distribution was analyzed by subcellular parting, using biotinylated heparin followed by colorimetric detection. HBP were detected as peripherical and integral periacrosomal membrane proteins. Indirect fluorescence microscopy of sperm incubated with biotinylated heparin was used to evidence heparin binding on sperm at different physiological stages. Two different fluorescent patterns (A and B) were found, which probably correspond to non-capacitated and capacitated sperm as assessed by the ability to undergo acrosome reaction with calcium ionophore A23187 and by the increase of p32 phosphorylated protein. In A pattern, corresponding to untreated sperm, fluorescence located mostly on the post-acrosomal region; in B pattern, corresponding to incubated sperm, on the acrosomal region. Upon incubation under capacitating conditions (TALP), sperm having the B pattern was augmented compared with non-incubated sperm (p<0.001). Differences in the HBP patterns (p<0.0001) were observed in sperm incubated under non-capacitating conditions in relation to sperm incubated in TALP, indicating that the modification of HBP patterns is probably related to capacitation. No difference was observed when untreated sperm were permeabilized prior to staining, suggesting that HBP are present on the sperm surface. The effect of heparin on capacitation dependent protein tyrosine phosphorylation was also analyzed, finding a decrease in p32 phosphorylation in the presence of heparin. This suggests that the capacitation enhancement mediated by this glycosaminoglycan involves an alternative intracellular pathway. The finding that heparin binds to sperm differently according to its physiological state, is a new evidence of the remodelling of sperm membrane surface upon capacitation and may provide a useful and relatively simple method to evaluate in vitro modification of boar sperm physiological

  6. Characterization of red-legged partridge (Alectoris rufa) sperm: Seasonal changes and influence of genetic purity.

    PubMed

    Santiago-Moreno, J; Castaño, C; Toledano-Díaz, A; Esteso, M C; López-Sebastián, A; Gañán, N; Hierro, M J; Marchal, F; Campo, J L; Blesbois, E

    2015-01-01

    The general decline in wild Iberian populations of the red-legged partridge (Alectoris rufa) has been accompanied by an increase in game-farm facilities producing hybrids with chukar partridges (Alectoris chukar). Genetic introgression from chukar partridges is thought to modify male red-legged partridge reproductive indicators. The aim of the present study was to determine the effects of such genetic introgression on seasonal reproductive patterns by comparing the sperm and plasma testosterone concentrations of males from pure red-legged and hybrid red-legged/chukar populations. Semen was collected twice monthly over a 12-mo period using a massage technique. Both types of bird showed a clear seasonal pattern of spermatogenic activity. The proportion of males ejaculating sperm was higher (P<0.05) among the pure red-legged birds. The greatest sperm production was recorded in March to May among the pure birds and April to May among the hybrids. Reproductive activity in both groups decreased in June, to reach a minimum in August to December among the hybrids and in September to December among the pure birds. Spermatogenic activity resumed in January in both groups. The sperm concentration produced by the pure birds was smaller than that of the hybrids (P<0.001), but the percentage of motile sperm was higher in the pure birds (P<0.001). The sperm of the hybrids showed greater straight-line velocity (P<0.05), linearity (P<0.001), straightness (P<0.001), sperm wobble (P<0.05), and beat-cross frequency values (P<0.001). The length and area of the sperm head were smaller in the pure birds (P<0.05). The seasonal plasma testosterone concentration pattern followed a trend roughly parallel to the ejaculatory response. The present results suggest that genetic introgression influences the reproductive variables of the red-legged partridge. PMID:25577796

  7. Elevated frequencies of hyperhaploid sperm were detected in a man with a history of multiple aneuploid pregnancies

    SciTech Connect

    Chuu, Y.J.; Wyrobek, A.J.; Kidd, S.

    1997-10-01

    The goal of this research is to determine the heritable risk associated with elevations in the proportion of hyperhaploid human sperm. A case family presented with a history of four aneuploid pregnancies: two with autosomal trisomies (47,+ 22 and 47, +15) which were non-viable and two children with sex chromosomal aneuploidies (47, XYY and Klinefelter syndrome, 47, XXY). The father consumed {approximately}{1/2} pack of cigarettes and 1 alcoholic drink per day. He had no notable occupational or environmental exposures. Paternal origin of extra X chromosomes in the boy with Klinefelter syndrome was confirmed by DNA analyses of blood using polymorphic X-linked microsatellite markers. The inheritance pattern was established by {ge}2 informative loci using PCR products analyzed on an automatic DNA sequencer. Multi-probe sperm FISH was employed to determine the proportion of sperm with aneuploidies involving chromosome 21, X, and Y. Sperm aneuploidy frequencies of hyper-haploid sperm; XY ({approximately}6 fold, p < 0.001), 21-21 ({approximately}6 fold, p< 0.001), XX and YY ({approximately}2 fold, p<0.02). These findings suggest that elevated proportions of aneuploid sperm may be associated with an increased risk of fathering an aneuploid offspring. These findings are also relevant for future studies of heritable risk for men with elevations in sperm aneuploidy after exposures to therapeutic or environmental agents.

  8. Long-term effects of triethylenemelamine exposure on mouse testis cells and sperm chromatin structure assayed by flow cytometry

    SciTech Connect

    Evenson, D.P.; Baer, R.K.; Jost, L.K. )

    1989-01-01

    The toxic and potentially mutagenic actions of triethylenemelamine (TEM) on mouse body and testis weights, testicular cell kinetics, sperm production, sperm head morphology, and sperm chromatin structure were assessed in two experiments. The first experiment examined effects of four dose levels of TEM, assayed 1, 4, or 10 wk after toxic exposure. In the second study, effects from five dosage levels were measured at 1, 4, and 10 wk, and the highest dosage level was evaluated over 44 wk. TEM produced an expected dose related loss of spermatogenic activity and subsequent recovery as determined by dual-parameter (DNA, RNA) flow cytometry (FCM) measurements of testicular cells. Both testicular weights and caudal sperm reserves remained generally below controls after 44 wk recovery following exposure to the highest dosage. Chromatin structure alterations, defined as increased susceptibility to DNA denaturation in situ, and sperm head morphology were highly correlated with dose and with each other. Sperm head morphology and sperm chromatic structure remained abnormal at 44 wk for the 1.0 mg/kg TEM dosage, suggesting that the abnormalities, present long after the initial toxic response, may be a result of mutation. This study demonstrates that flow cytometry provides a unique, rapid, and efficient means to measure effects of reproductive toxins and potential mutagens.

  9. Sodium affects the sperm motility in the European eel.

    PubMed

    Vílchez, M Carmen; Morini, Marina; Peñaranda, David S; Gallego, Víctor; Asturiano, Juan F; Pérez, Luz

    2016-08-01

    The role of seminal plasma sodium and activation media sodium on sperm motility was examined by selectively removing the element from these two media, in European eel sperm. Sperm size (sperm head area) was also measured using an ASMA (Automated Sperm Morphometry Analyses) system, in the different conditions. Intracellular sodium [Na(+)]i was quantitatively analyzed by first time in the spermatozoa from a marine fish species. Measurement of [Na(+)]i was done before and after motility activation, by Flow Cytometry, using CoroNa Green AM as a dye. Sperm motility activation induced an increase in [Na(+)]i, from 96.72mM in quiescent stage to 152.21mM post-activation in seawater. A significant decrease in sperm head area was observed post-activation in seawater. There was a notable reduction in sperm motility when sodium was removed from the seminal plasma, but not when it was removed from the activation media. Sodium removal was also linked to a significant reduction in sperm head area in comparison to the controls. Our results indicate that the presence of the ion Na(+) in the seminal plasma (or in the extender medium) is necessary for the preservation of sperm motility in European eel, probably because it plays a role in maintaining an appropriate sperm cell volume in the quiescent stage of the spermatozoa. PMID:27085371

  10. Rheotaxis guides mammalian sperm

    PubMed Central

    Miki, Kiyoshi; Clapham, David E

    2013-01-01

    Background In sea urchins, spermatozoan motility is altered by chemotactic peptides, giving rise to the assumption that mammalian eggs also emit chemotactic agents that guide spermatozoa through the female reproductive tract to the mature oocyte. Mammalian spermatozoa indeed undergo complex adaptations within the female (the process of capacitation) that are initiated by agents ranging from pH to progesterone, but these factors are not necessarily taxic. Currently, chemotaxis, thermotaxis, and rheotaxis have not been definitively established in mammals. Results Here, we show that positive rheotaxis, the ability of organisms to orient and swim against the flow of surrounding fluid, is a major taxic factor for mouse and human sperm. This flow is generated within 4 hours of sexual stimulation and coitus in female mice; prolactin-triggered oviductal fluid secretion clears the oviduct of debris, lowers viscosity, and generates the stream that guides sperm migration in the oviduct. Rheotaxic movement is demonstrated in capacitated and uncapacitated spermatozoa in low and high viscosity medium. Finally, we show that a unique sperm motion we quantify using the sperm head's rolling rate reflects sperm rotation that generates essential force for positioning the sperm in the stream. Rotation requires CatSper channels, presumably by enabling Ca2+ influx. Conclusions We propose that rheotaxis is a major determinant of sperm guidance over long distances in the mammalian female reproductive tract. Coitus induces fluid flow to guide sperm in the oviduct. Sperm rheotaxis requires rotational motion during CatSper channel-dependent hyperactivated motility. PMID:23453951

  11. Cryopreservation of Sperm from the Endangered Colorado Pikeminnow

    USGS Publications Warehouse

    Tiersch, T.R.; Figiel, C.R., Jr.; Wayman, W.R.; Williamson, J.H.; Gorman, O.T.; Carmichael, G.J.

    2004-01-01

    We developed methods for the cryopreservation of sperm of the endangered Colorado pikeminnow Ptychocheilus lucius. Sperm were collected from a captive broodstock population of Colorado pikeminnow reared and maintained at the Dexter National Fish Hatchery and Technology Center. Our objectives were to (1) evaluate the effects on sperm motility of 24-h storage in Hanks' balanced salt solution (HBSS); (2) characterize sperm motility and duration; (3) examine the relationship between sperm motility and osmotic pressure; (4) examine the effect of four cryoprotectants (dimethyl sulfoxide [DMSO], dimethyl acetamide [DMA], glycerol, and methanol [MeOH] at two concentrations [5% and 10%]) on postthaw motility; and (5) compare the effect of two cooling rates (40??C/ min and 4??C/min) on postthaw motility. The sperm samples diluted with HBSS retained higher motility (mean ??SD, 77 ?? 22%; n = 9) than did undiluted samples (12 ?? 30%; n = 9) after 24 h of storage. When exposed to HBSS at 274 mosmols/kg or more, few sperm became motile (???1%). Exposure to HBSS at 265 mosmols/kg elicited threshold activation (defined as 10% motility), and maximum motility (>95%) was observed at 93 mosmols/ kg. The maximum motility of sperm was observed within 10 s after activation with deionized water, and sperm remained motile for 57 s. The sperm that were cooled at a rate of 40??C/min and cryopreserved with 5% MeOH retained higher postthaw motility (56 ?? 13%) than did sperm cryopreserved with DMSO, DMA, or glycerol (at 5% and 10%). When the sperm samples were cooled at a rate of 4??C/min, sperm cryopreserved with MeOH (5% or 10%) or DMSO (5% or 10%) retained the highest postthaw motilities (???14%). The use of cryopreserved sperm can assist hatchery managers in the production of fish, provide for the long-term conservation of genetic resources, and assist in the recovery of endangered species such as the Colorado pikeminnow.

  12. Evaluation of Lasting Effects of Heat Stress on Sperm Profile and Oxidative Status of Ram Semen and Epididymal Sperm

    PubMed Central

    Hamilton, Thais Rose dos Santos; Mendes, Camilla Mota; de Castro, Letícia Signori; de Assis, Patrícia Monken; Siqueira, Adriano Felipe Perez; Delgado, Juliana de Carvalho; Goissis, Marcelo Demarchi; Muiño-Blanco, Teresa; Cebrián-Pérez, José Álvaro; Nichi, Marcílio; Visintin, José Antonio; Assumpção, Mayra Elena Ortiz D'Ávila

    2016-01-01

    Higher temperatures lead to an increase of testicular metabolism that results in spermatic damage. Oxidative stress is the main factor responsible for testicular damage caused by heat stress. The aim of this study was to evaluate lasting effects of heat stress on ejaculated sperm and immediate or long-term effects of heat stress on epididymal sperm. We observed decrease in motility and mass motility of ejaculated sperm, as well as an increase in the percentages of sperm showing major and minor defects, damaged plasma and acrosome membranes, and a decrease in the percentage of sperm with high mitochondrial membrane potential in the treated group until one spermatic cycle. An increased enzymatic activity of glutathione peroxidase and an increase of stressed cells were observed in ejaculated sperm of the treated group. A decrease in the percentage of epididymal sperm with high mitochondrial membrane potential was observed in the treated group. However, when comparing immediate and long-term effects, we observed an increase in the percentage of sperm with low mitochondrial membrane potential. In conclusion, testicular heat stress induced oxidative stress that led to rescuable alterations after one spermatic cycle in ejaculated sperm and also after 30 days in epididymal sperm. PMID:26881013

  13. Etiologies of sperm oxidative stress

    PubMed Central

    Sabeti, Parvin; Pourmasumi, Soheila; Rahiminia, Tahereh; Akyash, Fatemeh; Talebi, Ali Reza

    2016-01-01

    Sperm is particularly susceptible to reactive oxygen species (ROS) during critical phases of spermiogenesis. However, the level of seminal ROS is restricted by seminal antioxidants which have beneficial effects on sperm parameters and developmental potentials. Mitochondria and sperm plasma membrane are two major sites of ROS generation in sperm cells. Besides, leukocytes including polymer phonuclear (PMN) leukocytes and macrophages produce broad category of molecules including oxygen free radicals, non-radical species and reactive nitrogen species. Physiological role of ROS increase the intracellular cAMP which then activate protein kinase in male reproductive system. This indicates that spermatozoa need small amounts of ROS to acquire the ability of nuclear maturation regulation and condensation to fertilize the oocyte. There is a long list of intrinsic and extrinsic factors which can induce oxidative stress to interact with lipids, proteins and DNA molecules. As a result, we have lipid peroxidation, DNA fragmentation, axonemal damage, denaturation of the enzymes, over generation of superoxide in the mitochondria, lower antioxidant activity and finally abnormal spermatogenesis. If oxidative stress is considered as one of the main cause of DNA damage in the germ cells, then there should be good reason for antioxidant therapy in these conditions. PMID:27351024

  14. Etiologies of sperm oxidative stress.

    PubMed

    Sabeti, Parvin; Pourmasumi, Soheila; Rahiminia, Tahereh; Akyash, Fatemeh; Talebi, Ali Reza

    2016-04-01

    Sperm is particularly susceptible to reactive oxygen species (ROS) during critical phases of spermiogenesis. However, the level of seminal ROS is restricted by seminal antioxidants which have beneficial effects on sperm parameters and developmental potentials. Mitochondria and sperm plasma membrane are two major sites of ROS generation in sperm cells. Besides, leukocytes including polymer phonuclear (PMN) leukocytes and macrophages produce broad category of molecules including oxygen free radicals, non-radical species and reactive nitrogen species. Physiological role of ROS increase the intracellular cAMP which then activate protein kinase in male reproductive system. This indicates that spermatozoa need small amounts of ROS to acquire the ability of nuclear maturation regulation and condensation to fertilize the oocyte. There is a long list of intrinsic and extrinsic factors which can induce oxidative stress to interact with lipids, proteins and DNA molecules. As a result, we have lipid peroxidation, DNA fragmentation, axonemal damage, denaturation of the enzymes, over generation of superoxide in the mitochondria, lower antioxidant activity and finally abnormal spermatogenesis. If oxidative stress is considered as one of the main cause of DNA damage in the germ cells, then there should be good reason for antioxidant therapy in these conditions. PMID:27351024

  15. Standards in reporting cryopreserved donor sperm characteristics: should they be reported post-thaw or post-wash?

    PubMed

    Tomlinson, Mathew J; Comajuan, Estel; Naeem, Asad; Pooley, Karen

    2016-07-01

    An increase in the reliance on imported donor samples has been the consequence of a continued shortage of UK donors. Disputes can arise between suppliers and purchasers if the sperm quality is not as expected, yet there appears to be no requirement for the standardization of methods for sperm processing or analysis. Following analysis of 102 donor intrauterine insemination cycles, this study demonstrates that the motile sperm concentration is significantly (P < 0.05) reduced after the necessary removal of cryoprotectant before insemination. Suppliers of donor spermatozoa should therefore provide information on standards used for sperm assessment and whether analysis is performed before or after washing in order that purchasers are better informed about the quality of the end product they are committed to buying. PMID:27085963

  16. An ARID Domain-Containing Protein within Nuclear Bodies Is Required for Sperm Cell Formation in Arabidopsis thaliana

    PubMed Central

    Zheng, Binglian; He, Hui; Zheng, Yanhua; Wu, Wenye; McCormick, Sheila

    2014-01-01

    In plants, each male meiotic product undergoes mitosis, and then one of the resulting cells divides again, yielding a three-celled pollen grain comprised of a vegetative cell and two sperm cells. Several genes have been found to act in this process, and DUO1 (DUO POLLEN 1), a transcription factor, plays a key role in sperm cell formation by activating expression of several germline genes. But how DUO1 itself is activated and how sperm cell formation is initiated remain unknown. To expand our understanding of sperm cell formation, we characterized an ARID (AT-Rich Interacting Domain)-containing protein, ARID1, that is specifically required for sperm cell formation in Arabidopsis. ARID1 localizes within nuclear bodies that are transiently present in the generative cell from which sperm cells arise, coincident with the timing of DUO1 activation. An arid1 mutant and antisense arid1 plants had an increased incidence of pollen with only a single sperm-like cell and exhibited reduced fertility as well as reduced expression of DUO1. In vitro and in vivo evidence showed that ARID1 binds to the DUO1 promoter. Lastly, we found that ARID1 physically associates with histone deacetylase 8 and that histone acetylation, which in wild type is evident only in sperm, expanded to the vegetative cell nucleus in the arid1 mutant. This study identifies a novel component required for sperm cell formation in plants and uncovers a direct positive regulatory role of ARID1 on DUO1 through association with histone acetylation. PMID:25057814

  17. Long-term effects of triethylenemelamine exposure on mouse testis cells and sperm chromatin structure assayed by flow cytometry.

    PubMed

    Evenson, D P; Baer, R K; Jost, L K

    1989-01-01

    The toxic and potentially mutagenic actions of triethylenemelamine (TEM) on mouse body and testis weights, testicular cell kinetics, sperm production, sperm head morphology, and sperm chromatin structure were assessed in two experiments. The first experiment examined effects of four dose levels of TEM, assayed 1, 4, and 10 wk after toxic exposure. In the second study, effects from five dosage levels were measured at 1, 4, and 10 wk, and the highest dosage level was evaluated over 44 wk. TEM produced an expected dose related loss of spermatogenic activity and subsequent recovery as determined by dual-parameter (DNA, RNA) flow cytometry (FCM) measurements of testicular cells. Both testicular weights and caudal sperm reserves remained generally below controls after 44 wk recovery following exposure to the highest (1.0 mg/kg daily x 5) dosage. Chromatin structure alterations, defined as increased susceptibility to DNA denaturation in situ, and sperm head morphology were highly correlated (.87-.93, P less than .001) with dose and with each other. Data obtained from the sperm chromatin structure essay (SCSA) on fresh sperm was highly correlated with measurements of aliquots of the same sample collected over 44 wk, frozen, and then measured on the same day. Sperm head morphology and sperm chromatin structure remained abnormal at 44 wk for the 1.0 mg/kg TEM dosage, suggesting that the abnormalities, present long after the initial toxic response, may be a result of mutation. This study demonstrates that flow cytometry provides a unique, rapid, and efficient means to measure effects of reproductive toxins and potential mutagens. PMID:2767059

  18. Male mammals respond to a risk of sperm competition conveyed by odours of conspecific males

    NASA Astrophysics Data System (ADS)

    delBarco-Trillo, Javier; Ferkin, Michael H.

    2004-09-01

    Sperm competition occurs when a female copulates with two or more males and the sperm of those males compete within the female's reproductive tract to fertilize her eggs. The frequent occurrence of sperm competition has forced males of many species to develop different strategies to overcome the sperm of competing males. A prevalent strategy is for males to increase their sperm investment (total number of sperm allocated by a male to a particular female) after detecting a risk of sperm competition. It has been shown that the proportion of sperm that one male contributes to the sperm pool of a female is correlated with the proportion of offspring sired by that male. Therefore, by increasing his sperm investment a male may bias a potential sperm competition in his favour. Here we show that male meadow voles, Microtus pennsylvanicus, increase their sperm investment when they mate in the presence of another male's odours. Such an increase in sperm investment does not occur by augmenting the frequency of ejaculations, but by increasing the amount of sperm in a similar number of ejaculations.

  19. Sperm motility-initiating substance in newt egg-jelly induces differential initiation of sperm motility based on sperm intracellular calcium levels.

    PubMed

    Watanabe, Akihiko; Takayama-Watanabe, Eriko; Vines, Carol A; Cherr, Gary N

    2011-01-01

    Sperm motility-initiating substance (SMIS), a novel motility inducer from newt egg-jelly, is activated by the release from associated jelly substances at the beginning of internal fertilization and affects female-stored sperm. We examined motility initiation kinetics of newt sperm in response to SMIS by monitoring the changes of sperm intracellular calcium ([Ca²(+)](i)). In quiescent non-motile sperm loaded with the Ca²(+) indicator Fluo-4, intracellular free Ca²(+) was observed around mitochondria using confocal scanning laser microscopy. A slight increase in [Ca²(+)](i) occurred simultaneously and transiently at motility initiation in sperm treated with either heated jelly extract (hJE) containing activated SMIS, or a low osmotic solution, which naturally initiates motility in externally-fertilizing amphibians and can initiate motility in urodele sperm. When the increase of [Ca²(+)](i) at motility-initiation was monitored using spectrofluorometry, large increases in [Ca²(+)](i) occurred immediately in the low osmotic solution and within 1.5 min in the hJE. In the intact jelly extract (no heating), small increases of [Ca²(+)](i) irregularly occurred from around 1 min and for about 4 min, during which motility was differentially initiated among sperm. These results indicate that the SMIS induces differential initiation of sperm motility depending on the activational states of the SMIS and its overall activity. The motility initiation in the jelly extract was delayed in sperm whose intracellular Ca²(+) had been chelated with BAPTA-AM. The relative levels of [Ca²(+)](i) were variable with a mean of 414 ± 256 nmol/L among resting sperm, suggesting that the level of [Ca²(+)](i) in the resting sperm modulates the responsiveness to the SMIS. PMID:21261606

  20. Foetal and post-natal exposure of sheep to sewage sludge chemicals disrupts sperm production in adulthood in a subset of animals

    PubMed Central

    Bellingham, M; McKinnell, C; Fowler, P A; Amezaga, M R; Zhang, Z; Rhind, S M; Cotinot, C; Mandon-Pepin, B; Evans, N P; Sharpe, R M

    2012-01-01

    Exposure to ubiquitous, environmental chemicals (ECs) has been hypothesized as a cause for declining male reproductive health. Understanding the long-term effects of EC exposure on reproductive health in humans requires animal models and exposure to ‘real life’, environmentally relevant, mixtures during development, a life stage of particular sensitivity to ECs. The aim of this study was to evaluate the effects of in utero and post-natal exposure to environmentally relevant levels of ECs, via sewage sludge application to pasture, on the adult male sheep testis. Hormones, liver concentrations of candidate ECs and Sertoli and germ cell numbers in testes of adult rams that were exposed to ECs in sewage sludge in utero, and until weaning via maternal exposure, and post-weaning via grazing pastures fertilized with sewage sludge, were quantified. Evaluated as a single group, exposure to sludge ECs was without significant effect on most parameters. However, a more detailed study revealed that 5 of 12 sludge-exposed rams exhibited major spermatogenic abnormalities. These consisted of major reductions in germ cell numbers per testis or per Sertoli cell and more Sertoli cell-only tubules, when compared with controls, which did not show any such changes. The sludge-related spermatogenic changes in the five affected animals were significantly different from controls (p < 0.001); Sertoli cell number was unaffected. Hormone profiles and liver candidate EC concentrations were not measurably affected by exposure. We conclude that developmental exposure of male sheep to real-world mixtures of ECs can result in major reduction in germ cell numbers, indicative of impaired sperm production, in a proportion of exposed males. The individual-specific effects are presumed to reflect EC effects on a heterogeneous population in which some individuals may be more susceptible to adverse EC effects. Such effects of EC exposure in humans could have adverse consequences for sperm counts and

  1. Human sperm chromosome analysis after subzonal sperm insemination of hamster oocytes

    SciTech Connect

    Cozzi, J.

    1994-09-01

    Sperm microinjection techniques, subzonal sperm insemination (SUZI) and intracytoplasmic sperm injection (ICSI), have achieved a wide spread clinical application for the treatment of male infertility. To date, only one study has focused on sperm karyotypes after microinjection. Martin et al. reported a very high incidence of abnormal human sperm complements after ICSI into hamster oocytes. In the present study, are reported the first human sperm karyotypes after SUZI of hamster oocytes. Spermatozoa from two control donors were treated by calcium ionophore A23187 and injected under the zona of hamster eggs. The microinjected eggs were then cultured for cytogenetic analysis of the pronuclei. Out of 47 analyzed sperm chromosome metaphases, 5 (10.6%) were abnormal, 4 (8.5%) were hypohaploid and 1 (2.1%) had a structural abnormality. The sex ratio was not significantly different from the expected 1:1 ratio. Rates of chromosomal abnormalities in microinjected spermatozoa were similar to those observed in spermatozoa inseminated with zona free eggs, suggesting that SUZI procedure per se does not increase sperm chromosomal abnormalities.

  2. Melatonin controlled apoptosis and protected the testes and sperm quality against bisphenol A-induced oxidative toxicity.

    PubMed

    Othman, Azza I; Edrees, Gamal M; El-Missiry, Mohamed A; Ali, Doaa A; Aboel-Nour, Mohamed; Dabdoub, Banan R

    2016-09-01

    Epidemiological reports have indicated a correlation between the increasing bisphenol A (BPA) levels in the environment and the incidence of male infertility. In this study, the protective effects of melatonin on BPA-induced oxidative stress and apoptosis were investigated in the rat testes and epididymal sperm. Melatonin (10 mg/kg body weight (bw)) was injected concurrently with BPA (50 mg/kg bw) for 3 and 6 weeks. The administration of BPA significantly increased oxidative stress in the testes and epididymal sperm. This was associated with a decrease in the serum testosterone level as well as sperm quality, chromatin condensation/de-condensation level, and the percentage of haploid germ cells in the semen. BPA administration caused a significant increase in apoptosis accompanied by a decrease in the expression of the antiapoptotic proteins Bcl-2 in the testes and epididymal sperm. The concurrent administration of melatonin decreased oxidative stress by modulating the levels of glutathione, superoxide dismutase, and catalase as well as the malondialdehyde and hydrogen peroxide concentrations in the testes and sperm. Melatonin sustained Bcl-2 expression and controlled apoptosis. Furthermore, melatonin maintained the testosterone levels, ameliorated histopathological changes, increased the percentages of seminal haploid germ cells, and protected sperm chromatin condensation process, indicating appropriate spermatogenesis with production of functional sperm. In conclusion, melatonin protected against BPA-induced apoptosis by controlling Bcl-2 expression and ameliorating oxidative stress in the testes and sperm. Thus, melatonin is a promising pharmacological agent for preventing the potential reproductive toxicity of BPA following occupational or environmental exposures. PMID:25537623

  3. Sperm Patch-Clamp

    PubMed Central

    Lishko, Polina; Clapham, David E.; Navarro, Betsy; Kirichok, Yuriy

    2014-01-01

    Sperm intracellular pH and calcium concentration ([Ca2+]i) are two central factors that control sperm activity within the female reproductive tract. As such, the ion channels of the sperm plasma membrane that alter intracellular sperm [Ca2+] and pH play important roles in sperm physiology and the process of fertilization. Indeed, sperm ion channels regulate sperm motility, control sperm chemotaxis toward the egg in some species, and may trigger the acrosome reaction. Until recently, our understanding of these important molecules was rudimentary due to the inability to patch-clamp spermatozoa and directly record the activity of these ion channels under voltage clamp. Recently, we overcame this technical barrier and developed a method for reproducible application of the patch-clamp technique to mouse and human spermatozoa. This chapter covers important aspects of application of the patch-clamp technique to spermatozoa, such as selection of the electrophysiological equipment, isolation of spermatozoa for patch-clamp experiments, formation of the gigaohm seal with spermatozoa, and transition into the whole-cell mode of recording. We also discuss potential pitfalls in application of the patch-clamp technique to flagellar ion channels. PMID:23522465

  4. Current status of freeze-drying technology to preserve domestic animals sperm.

    PubMed

    Gil, L; Olaciregui, M; Luño, V; Malo, C; González, N; Martínez, F

    2014-10-01

    In recent years, there has been an increased interest in new preservation techniques that facilitate sperm storage and distribution, with freeze-drying (FD) having been proposed as an alternative method for sperm preservation and maintenance of genetic resources in different animal species. FD is a method in which frozen material is dried by sublimation of ice, thereby involving a direct transition from a solid (ice) to a vapour (gas) phase. One of the main advantages of FD is that nitrogen and dry ice are no longer required for the storage and shipment of frozen sperm, which can be stored at room temperature or 4°C, thereby resulting in enormous reductions in storage and shipping costs. Unlike sperm cryopreserved after gradual freezing, the sperm membrane may be further damaged by both snap-freezing and drying stresses during the FD procedure. As mammalian spermatozoa lose their motility, viability and, at least partially, their DNA integrity when freeze-dried, they must be microinjected into an oocyte by intracytoplasmic sperm injection (ICSI). Although the efficiency of ICSI is limited when freeze-dried spermatozoa are used, embryos and live offspring can be produced. DNA fragmentation in freeze-dried spermatozoa is one of the main causes of failure of embryonic development and successful pregnancy. In this regard, it has been suggested that endonucleases are among the leading causes of DNA fragmentation in spermatozoa along with oxidative stress caused by the release of reactive oxygen species (ROS). Many factors influence the FD process, and it is not clear how FD affects specific components of sperm from different animal species. As such, a sound understanding of the FD process would result in increased production of embryos and/or live offspring. The aim of this review was to study the various stages and techniques used in the FD process and to further evaluate the results obtained. PMID:25277435

  5. Impact of increasing milk production on whole farm environmental management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing herd milk production can provide both economic benefit to the producer and environmental benefit to society. Simulated dairy farms with average annual herd productions from 16,000 to 30,000 lb/cow illustrate that increasing milk yield per cow improves feed efficiency, reduces feed costs a...

  6. State Policies and Planning to Increase Attainment, Quality, and Productivity

    ERIC Educational Resources Information Center

    Lingenfelter, Paul E.

    2007-01-01

    This article examines why state planning and policy for higher education are increasingly focused on increasing educational attainment, quality, and the productivity of the system. It presents four "stories" which illustrate initiatives to improve attainment, quality, and productivity, but fall far short of exhausting the available material.

  7. Mammalian Sperm Motility: Observation and Theory

    NASA Astrophysics Data System (ADS)

    Gaffney, E. A.; Gadêlha, H.; Smith, D. J.; Blake, J. R.; Kirkman-Brown, J. C.

    2011-01-01

    Mammalian spermatozoa motility is a subject of growing importance because of rising human infertility and the possibility of improving animal breeding. We highlight opportunities for fluid and continuum dynamics to provide novel insights concerning the mechanics of these specialized cells, especially during their remarkable journey to the egg. The biological structure of the motile sperm appendage, the flagellum, is described and placed in the context of the mechanics underlying the migration of mammalian sperm through the numerous environments of the female reproductive tract. This process demands certain specific changes to flagellar movement and motility for which further mechanical insight would be valuable, although this requires improved modeling capabilities, particularly to increase our understanding of sperm progression in vivo. We summarize current theoretical studies, highlighting the synergistic combination of imaging and theory in exploring sperm motility, and discuss the challenges for future observational and theoretical studies in understanding the underlying mechanics.

  8. Changing climate increases biological productivity in the Arctic

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2011-11-01

    Climate change is leading to increased biological productivity in the coastal Arctic. As ice melts and recedes far from land, winds interact with open waters to increase the upwelling of nutrient-rich deep water and stimulate biological productivity. Tremblay et al. quantified these changes using remote sensing and in situ observations in the coastal Beaufort Sea. They found that ice ablation and the combination of increased upwelling and greater light penetration into the water column during fall 2007 and summer 2008 increased the production of ice algae, phytoplankton, and zooplankton by 2-6 times. (Geophysical Research Letters, doi:10.1029/2011GL048825, 2011)

  9. Methods for sperm concentration determination.

    PubMed

    Björndahl, Lars

    2013-01-01

    Proper assessment of the number of spermatozoa is essential not only as an initial step in every clinical infertility investigation [Björndahl et al (2010) A practical guide to basic laboratory andrology, 1st edn. Cambridge University Press, Cambridge] but also when attempting to establish the total sperm production in the testis [Amann (Hum Reprod 25:22-28, 2010); Amann (J Androl 30:626-641, 2009); Amann and Chapman (J Androl 30:642-649, 2009)]. Reliable methods combined with an understanding of the specific physiology involved as well as the main sources of errors related to the assessment of sperm concentration are critical for ensuring accurate concentration determination [Björndahl et al (2010) A practical guide to basic laboratory andrology, 1st edn. Cambridge University Press, Cambridge; World Health Organization (2010) WHO laboratory manual for the examination and processing of human semen. WHO, Geneva]. This chapter therefore focuses on these three aspects. PMID:22992898

  10. Speract, a sea urchin egg peptide that regulates sperm motility, also stimulates sperm mitochondrial metabolism.

    PubMed

    García-Rincón, Juan; Darszon, Alberto; Beltrán, Carmen

    2016-04-01

    Sea urchin sperm have only one mitochondrion, that in addition to being the main source of energy, may modulate intracellular Ca(2+) concentration ([Ca(2+)]i) to regulate their motility and possibly the acrosome reaction. Speract is a decapeptide from the outer jelly layer of the Strongylocentrotus purpuratus egg that upon binding to its receptor in the sperm, stimulates sperm motility, respiration and ion fluxes, among other physiological events. Altering the sea urchin sperm mitochondrial function with specific inhibitors of this organelle, increases [Ca(2+)]i in an external Ca(2+) concentration ([Ca(2+)]ext)-dependent manner (Ardón, et al., 2009. BBActa 1787: 15), suggesting that the mitochondrion is involved in sperm [Ca(2+)]i homeostasis. To further understand the interrelationship between the mitochondrion and the speract responses, we measured mitochondrial membrane potential (ΔΨ) and NADH levels. We found that the stimulation of sperm with speract depolarizes the mitochondrion and increases the levels of NADH. Surprisingly, these responses are independent of external Ca(2+) and are due to the increase in intracellular pH (pHi) induced by speract. Our findings indicate that speract, by regulating pHi, in addition to [Ca(2+)]i, may finely modulate mitochondrial metabolism to control motility and ensure that sperm reach the egg and fertilize it. PMID:26772728

  11. Wolbachia infection lowers fertile sperm transfer in a moth

    PubMed Central

    Lewis, Z.; Champion de Crespigny, F. E.; Sait, S. M.; Tregenza, T.; Wedell, N.

    2011-01-01

    The endosymbiotic bacterium Wolbachia pipientis manipulates host reproduction by rendering infected males reproductively incompatible with uninfected females (cytoplasmic incompatibility; CI). CI is believed to occur as a result of Wolbachia-induced modifications to sperm during maturation, which prevent infected sperm from initiating successful zygote development when fertilizing uninfected females' eggs. However, the mechanism by which CI occurs has been little studied outside the genus Drosophila. Here, we show that in the sperm heteromorphic Mediterranean flour moth, Ephestia kuehniella, infected males transfer fewer fertile sperm at mating than uninfected males. In contrast, non-fertile apyrene sperm are not affected. This indicates that Wolbachia may only affect fertile sperm production and highlights the potential of the Lepidoptera as a model for examining the mechanism by which Wolbachia induces CI in insects. PMID:20880864

  12. Effects of reactive oxygen species on sperm function.

    PubMed

    Guthrie, H D; Welch, G R

    2012-11-01

    Reactive oxygen species (ROS) formation and membrane lipid peroxidation have been recognized as problems for sperm survival and fertility. The precise roles and detection of superoxide (SO), hydrogen peroxide (HP), and membrane lipid peroxidation have been problematic, because of the low specificity and sensitivity of the established chemiluminescence assay technologies. We developed flow cytometric assays to measure SO, HP, membrane lipid peroxidation, and inner mitochondrial transmembrane potential in boar sperm. These methods were sufficiently sensitive to permit detection of early changes in ROS formation in sperm cells that were still viable. Basal ROS formation and membrane lipid peroxidation in the absence of ROS generators were low in viable sperm of both fresh and frozen-thawed boar semen, affecting less than 4% of the sperm cells on average. However, this is not the case in other species, as human, bovine, and poultry sperm have large increases in sperm ROS formation, lipid peroxidation, loss of motility, and death in vitro. Closer study of the effects of ROS formation on the relationship between sperm motility and ATP content in boar sperm was conducted using menadione (mitochondrial SO generator) and HP treatment. Menadione or HP caused an immediate disruption of motility with delayed or no decrease in sperm ATP content, respectively. Overall, the inhibitory effects of ROS on motility point to a mitochondrial-independent mechanism. The reduction in motility may have been due to a ROS-induced lesion in ATP utilization or in the contractile apparatus of the flagellum. PMID:22704396

  13. Sperm chromatin condensation, DNA integrity, and apoptosis in men with spinal cord injury

    PubMed Central

    Talebi, Ali Reza; Khalili, Mohammad Ali; Vahidi, Serajodin; Ghasemzadeh, Jalal; Tabibnejad, Nasim

    2013-01-01

    Objectives To evaluate the effect of cord injury on (1) sperm parameters and (2) DNA chromatin status. Design Case–control study. Setting Data were collected from men referred to Research and Clinical Center for Infertility, Yazd, Iran. Participants Thirty infertile men with the presence of any level of spinal cord injury (SCI) were compared with 30 healthy donors with definite fertility and normal sperm parameters. Interventions Not applicable. Outcome measures Sperm chromatin integrity was assessed using aniline blue (AB), chromomycin A3 (CMA3), toluidine blue (TB), and acridine orange (AO) assays. The rate of apoptotic spermatozoa was evaluated with terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL) staining. Results Sperm concentration, motility, and morphology in men with SCI were significantly decreased compared with control group (P < 0.05). In addition, with regard to cytochemical staining and TUNEL test, the rate of reacted spermatozoa was increased significantly in SCI group when compared with the controls (P < 0.05). The majority of AB, TB, AO, and CMA3-reacted spermatozoa were higher than the “cut-off” value in men with SCI, as were the number of apoptotic spermatozoa stained with TUNEL. Conclusion Results showed that SCI disturbs sperm parameters, nuclear maturity, and DNA integrity of spermatozoa. Therefore, the production of spermatozoa with less condensed chromatin and more apoptotic rate increases after cord injury and this may be one possible cause of infertility following SCI. PMID:23809529

  14. Suprazero Cooling Rate, Rather Than Freezing Rate, Determines Post Thaw Quality Of Rhesus Macaque Sperm

    PubMed Central

    Martorana, Kelly; Klooster, Katie; Meyers, Stuart

    2013-01-01

    Sperm become most sensitive to cold shock when cooled from 37ºC to 5ºC at rates that are too fast or too slow; cold shock increases the susceptibility to oxidative damage due to its influence on reactive oxygen species (ROS) production ([1]. ROS are significant stress factors that are generated during cooling and low temperature storage, and may be a main cause of decreased motility and fertility upon warming. ROS have been shown to change cellular function through the disruption of the sperm plasma membrane and through damage to proteins and DNA. The objective of this study was to determine which cryopreservation rates result in the lowest degree of oxidative damage and greatest sperm quality. In the rhesus model it has not been determined whether suprazero cooling or subzero freezing rates causes a significant amount of ROS damage to sperm. Semen samples were collected from male rhesus macaques, washed, and resuspended in TEST-yolk cryopreservation buffer to 100 x 106 sperm/mL. Sperm were frozen in 0.5mL straws at four different combinations of suprazero and subzero rates. Three different suprazero rates were used between 22ºC and 0ºC: 0.5ºC/min (Slow), 45ºC/min (Medium), and 93ºC/min (Fast). These suprazero rates were used in combination with two different subzero rates for temperatures 0ºC to −110ºC: 42ºC/min (Medium) and 87ºC/min (Fast). The different freezing groups were as follows: Slow-Med (SM), Slow-Fast (SF), Med-Med (MM), and Fast-Fast (FF). Flow cytometry was used to detect lipid peroxidation (LPO), a result of ROS generation. Motility was evaluated using a computer assisted sperm motion analyzer. The MM and FF treated sperm had less viable (P < 0.0001) and motile sperm (P < 0.001) than the SM, SF, or fresh sperm. Sperm exposed to MM and FF treatments demonstrated significantly higher oxidative damage than SM, SF, or fresh sperm (P < 0.05). The SM and SF treated sperm showed decreased motility, membrane integrity, and LPO compared to fresh

  15. Factors associated with increased milk production for automatic milking systems.

    PubMed

    Tremblay, Marlène; Hess, Justin P; Christenson, Brock M; McIntyre, Kolby K; Smink, Ben; van der Kamp, Arjen J; de Jong, Lisanne G; Döpfer, Dörte

    2016-05-01

    Automatic milking systems (AMS) are increasingly popular throughout the world. Our objective was to analyze 635 North American dairy farms with AMS for (risk) factors associated with increased milk production per cow per day and milk production per robot per day. We used multivariable generalized mixed linear regressions, which identified several significant risk factors and interactions of risk factors associated with milk production. Free traffic was associated with increased production per cow and per robot per day compared with forced systems, and the presence of a single robot per pen was associated with decreased production per robot per day compared with pens using 2 robots. Retrofitted farms had significantly less production in the first 4 yr since installation compared with production after 4 yr of installation. In contrast, newly built farms did not see a significant change in production over time since installation. Overall, retrofitted farms did not produce significantly more or less milk than newly constructed farms. Detailed knowledge of factors associated with increased production of AMS will help guide future recommendations to producers looking to transition to an AMS and maximize their production. PMID:26898275

  16. Elemental composition of human semen is associated with motility and genomic sperm defects among older men

    PubMed Central

    Schmid, Thomas E.; Grant, Patrick G.; Marchetti, Francesco; Weldon, Rosana H.; Eskenazi, Brenda; Wyrobek, Andrew J.

    2013-01-01

    BACKGROUND Older men tend to have poorer semen quality and are generally at higher risks for infertility and abnormal reproductive outcomes. METHODS We employed proton-induced X-ray emission (PIXE, 3 MeV proton beam) to investigate the concentrations of zinc, copper, calcium, sulfur, chlorine, potassium, titanium, iron and nickel in washed sperm and seminal plasma from non-smoking groups of 10 older men (65–80 years old) and 10 younger men (22–28 years old) who were concurrently assayed for sperm function and genomicly defective sperm. RESULTS The older group showed elevated zinc, copper and calcium in sperm and elevated sulfur in seminal plasma compared with the younger men. The older group also showed reduced motility as well as increased sperm DNA fragmentation, achondroplasia mutations, DNA strand breaks and chromosomal aberrations. Sperm calcium and copper were positively associated with sperm DNA fragmentation (P < 0.03). Seminal sulfur was positively associated with sperm DNA fragmentation and chromosomal aberrations (P < 0.04), and negatively associated with sperm motility (P < 0.05). Sperm calcium was negatively associated with sperm motility, independent of male age (P = 0.01). CONCLUSIONS We identified major differences in elemental concentrations between sperm and seminal plasma and that higher sperm copper, sulfur and calcium are quantitatively associated with poorer semen quality and increased frequencies of genomic sperm defects. PMID:23042799

  17. Novel Flow Cytometry Analyses of Boar Sperm Viability: Can the Addition of Whole Sperm-Rich Fraction Seminal Plasma to Frozen-Thawed Boar Sperm Affect It?

    PubMed Central

    Díaz, Rommy; Boguen, Rodrigo; Martins, Simone Maria Massami Kitamura; Ravagnani, Gisele Mouro; Leal, Diego Feitosa; Oliveira, Melissa de Lima; Muro, Bruno Bracco Donatelli; Parra, Beatriz Martins; Meirelles, Flávio Vieira; Papa, Frederico Ozanan; Dell’Aqua, José Antônio; Alvarenga, Marco Antônio; Moretti, Aníbal de Sant’Anna; Sepúlveda, Néstor

    2016-01-01

    Boar semen cryopreservation remains a challenge due to the extension of cold shock damage. Thus, many alternatives have emerged to improve the quality of frozen-thawed boar sperm. Although the use of seminal plasma arising from boar sperm-rich fraction (SP-SRF) has shown good efficacy; however, the majority of actual sperm evaluation techniques include a single or dual sperm parameter analysis, which overrates the real sperm viability. Within this context, this work was performed to introduce a sperm flow cytometry fourfold stain technique for simultaneous evaluation of plasma and acrosomal membrane integrity and mitochondrial membrane potential. We then used the sperm flow cytometry fourfold stain technique to study the effect of SP-SRF on frozen-thawed boar sperm and further evaluated the effect of this treatment on sperm movement, tyrosine phosphorylation and fertility rate (FR). The sperm fourfold stain technique is accurate (R2 = 0.9356, p > 0.01) for simultaneous evaluation of plasma and acrosomal membrane integrity and mitochondrial membrane potential (IPIAH cells). Centrifugation pre-cryopreservation was not deleterious (p > 0.05) for any analyzed variables. Addition of SP-SRF after cryopreservation was able to improve total and progressive motility (p < 0.05) when boar semen was cryopreserved without SP-SRF; however, it was not able to decrease tyrosine phosphorylation (p > 0.05) or improve IPIAH cells (p > 0.05). FR was not (p > 0.05) statistically increased by the addition of seminal plasma, though females inseminated with frozen-thawed boar semen plus SP-SRF did perform better than those inseminated with sperm lacking seminal plasma. Thus, we conclude that sperm fourfold stain can be used to simultaneously evaluate plasma and acrosomal membrane integrity and mitochondrial membrane potential, and the addition of SP-SRF at thawed boar semen cryopreserved in absence of SP-SRF improve its total and progressive motility. PMID:27529819

  18. Sperm motility activation, sperm heterogeneity and sperm-female tract interactions in Bennett's wallaby (Macropus rufogriseus rufogriseus).

    PubMed

    Boere, Janneke; Díaz, Daniela Esteban; Holt, William V

    2011-01-01

    Sperm-oviduct interactions in Bennett's wallaby (Macropus rufogriseus rufogriseus) were investigated using in vitro cocultures of cauda epididymal spermatozoa and oviducal epithelial cells. Kidney epithelial cells were used as non-reproductive control tissues. Spermatozoa attached to epithelial cells of both origins, but sperm survival and activity was higher when cocultured with oviducal cells. New findings during live sperm-epithelial interactions included: (1) a high frequency of reversible head movements, from linear (streamlined configuration) to T shape (thumbtack configuration) in swimming spermatozoa immediately after the start of coculture; (2) the loss of sperm tails (tail shedding) increasing with time; and (3) interrupted swimming patterns, where periods of fast movement were interspersed with slower swimming while the spermatozoa interacted with the epithelial cell surface. Sperm motility activation responses were characterised after diluting the epididymal samples in phosphate-buffered saline, medium M199 and Tyrode's medium. The results confirmed that the marsupial oviduct is able to support the viability and motility of a sperm subpopulation for at least 20 h in vitro and suggest that some spermatozoa shed their tails after binding, possibly as a result of a selective process. PMID:21557927

  19. A sperm-activating peptide controls a cGMP-signaling pathway in starfish sperm.

    PubMed

    Matsumoto, Midori; Solzin, Johannes; Helbig, Annika; Hagen, Volker; Ueno, Sei-ichi; Kawase, Osamu; Maruyama, Yoshinori; Ogiso, Manabu; Godde, Matthias; Minakata, Hiroyuki; Kaupp, U Benjamin; Hoshi, Motonori; Weyand, Ingo

    2003-08-15

    Peptides released from eggs of marine invertebrates play a central role in fertilization. About 80 different peptides from various phyla have been isolated, however, with one exception, their respective receptors on the sperm surface have not been unequivocally identified and the pertinent signaling pathways remain ill defined. Using rapid mixing techniques and novel membrane-permeable caged compounds of cyclic nucleotides, we show that the sperm-activating peptide asterosap evokes a fast and transient increase of the cGMP concentration in sperm of the starfish Asterias amurensis, followed by a transient cGMP-stimulated increase in the Ca(2+) concentration. In contrast, cAMP levels did not change significantly and the Ca(2+) response evoked by photolysis of caged cAMP was significantly smaller than that using caged cGMP. By cloning of cDNA and chemical crosslinking, we identified a receptor-type guanylyl cyclase in the sperm flagellum as the asterosap-binding protein. Sperm respond exquisitely sensitive to picomolar concentrations of asterosap, suggesting that the peptide serves a chemosensory function like resact, a peptide involved in chemotaxis of sperm of the sea urchin Arbacia punctulata. A unifying principle emerges that chemosensory transduction in sperm of marine invertebrates uses cGMP as the primary messenger, although there may be variations in the detail. PMID:12921734

  20. Assay of sperm motility to study the effects of metal ions

    SciTech Connect

    Timourian, H.; Watchmaker, G.

    1984-01-01

    A method for quantitating sperm motility is applied here to study the effects of metal ions on animal cells. The quantitative technique is based on orienting sperm by subjecting them to flow and then measuring their capacity for returning to randomness when the orienting force is discontinued. The optical anisotropy of sperm permits determination of orientation with a spectrophotometer equipped with a flow cell. A wide range of concentrations of zinc, copper, and nickel ions were tested to determine their effects on the motility of sea-urchin sperm. Sea urchins are a ready and convenient source of sperm. Since energy production in sperm depends on their limited supply of endogenous substrate, this test system gives us a simple screening procedure for comparing the effects of various agents on the cell's capacity for utilizing energy. Nickel at concentrations higher than 10..pi../sup 5/M had an initial depressing effect on motility; however, this effect was eventually overcome, and in some cases overcompensation resulted in an increase motility. Zinc had either an enhancing or a depressing effect, depending not only on its concentration but on the time of exposure. At 10/sup -5/M it enhanced motility if present at the time the sperm were first shed in seawater, the time of high respiration. At 10..pi../sup 4/M it depressed motility only if present during the period of decreasing respiration, 1 to 2 hr after being shed into seawater. Copper depressed activity at 10..pi../sup 4/M to 10..pi../sup 6/M at all times tested.

  1. Supporters of sperm

    PubMed Central

    Løvlie, Hanne

    2014-01-01

    The Biology of Spermatozoa (BoS) meetings have run on a biannual basis since the early 1990s. They are dedicated to the fascinating research topic of sperm and their complicated route to fertilization. The BoS meetings focus on sperm, but they also explore additional supporting factors important in fertilization, such as those present in seminal and ovarian fluid, as well as the genomic bases of sperm biology. Here, I present a report of the recent BoS meeting, and showcase some of the highlights of this year’s meeting. PMID:25225623

  2. Sperm DNA oxidative damage and DNA adducts.

    PubMed

    Jeng, Hueiwang Anna; Pan, Chih-Hong; Chao, Mu-Rong; Lin, Wen-Yi

    2015-12-01

    The objective of this study was to investigate DNA damage and adducts in sperm from coke oven workers who have been exposed to polycyclic aromatic hydrocarbons. A longitudinal study was conducted with repeated measurements during spermatogenesis. Coke-oven workers (n=112) from a coke-oven plant served the PAH-exposed group, while administrators and security personnel (n=67) served the control. Routine semen parameters (concentration, motility, vitality, and morphology) were analyzed simultaneously; the assessment of sperm DNA integrity endpoints included DNA fragmentation, bulky DNA adducts, and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dGuo). The degree of sperm DNA fragmentation was measured using the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay and sperm chromatin structure assay (SCSA). The PAH-exposed group had a significant increase in bulky DNA adducts and 8-oxo-dGuo compared to the control subjects (Ps=0.002 and 0.045, respectively). Coke oven workers' percentages of DNA fragmentation and denaturation from the PAH-exposed group were not significantly different from those of the control subjects (Ps=0.232 and 0.245, respectively). Routine semen parameters and DNA integrity endpoints were not correlated. Concentrations of 8-oxo-dGuo were positively correlated with percentages of DNA fragmentation measured by both TUNEL and SCSA (Ps=0.045 and 0.034, respectively). However, the concentrations of 8-oxo-dGuo and percentages of DNA fragmentation did not correlate with concentrations of bulky DNA adducts. In summary, coke oven workers with chronic exposure to PAHs experienced decreased sperm DNA integrity. Oxidative stress could contribute to the degree of DNA fragmentation. Bulky DNA adducts may be independent of the formation of DNA fragmentation and oxidative adducts in sperm. Monitoring sperm DNA integrity is recommended as a part of the process of assessing the impact of occupational and environmental toxins on sperm

  3. Factors affecting production of transgenic rats by ICSI-mediated DNA transfer: effects of sonication and freeze-thawing of spermatozoa, rat strains for sperm and oocyte donors, and different constructs of exogenous DNA.

    PubMed

    Hirabayashi, Masumi; Kato, Megumi; Ishikawa, Ayako; Kaneko, Ryosuke; Yagi, Takeshi; Hochi, Shinichi

    2005-04-01

    Factors affecting the efficiency of producing transgenic rats by intracytoplasmic sperm injection (ICSI)-mediated DNA transfer were investigated. Epididymal spermatozoa from Sprague-Dawley (SD) rats were sonicated and/or frozen-thawed for cutting the tail and membrane disruption. The sperm heads were exposed for 1 min to different concentrations (0.02-2.5 microg/ml) of 3.0 kb enhanced green fluorescent protein (EGFP) DNA solution, and then microinjected into the denuded F1 hybrid (Donryu x LEW) rat oocytes. The optimal concentration of EGFP DNA solution was 0.1 microg/ml, as determined by the in vitro developmental competence into morulae/blastocysts of the ICSI oocytes and the EGFP expression of the resultant embryos. The efficiency of producing transgenic rat offspring (per transferred zygote) was 2.8%, 1.6%, and 3.3% in the oocytes injected with sonicated, frozen-thawed, and sonicated + frozen-thawed sperm heads, respectively. The founder transgenic rats carrying the EGFP gene transmitted their transgenes to their progeny according to the Mendelian fashion, suggesting the stable incorporation of the transgenes into the rat genomes. Four rat strains (F344, LEW, Donryu, and SD) were compared for their suitability as sperm/oocyte donors for the production of transgenic rats by ICSI with sonicated, frozen-thawed and solution of EGFP DNA-exposed sperm heads. The efficiency of producing transgenic rats in the SD strain (8.2%) was higher than that in the LEW strain (0.9%), while those in the F344 and Donryu strains (4.3%-4.4%) were intermediate. One plasmid DNA (Fyn, 5.0 kb) and two BAC DNA (BAC/Fyn, 208 kb; Svet1/IRES-Cre, 186 kb) were successfully introduced into the SD rat genomes via ICSI, with the producing efficiencies of 2.8%, 0.9%, and 2.4%, respectively. PMID:15685640

  4. Responses of primary productivity to increased temperature and phytoplankton diversity

    NASA Astrophysics Data System (ADS)

    Lewandowska, Aleksandra M.; Breithaupt, Petra; Hillebrand, Helmut; Hoppe, Hans-Georg; Jürgens, Klaus; Sommer, Ulrich

    2012-08-01

    In order to examine the effects of warming and diversity changes on primary productivity, we conducted a meta-analysis on six independent indoor mesocosm experiments with a natural plankton community from the Baltic Sea. Temperature effects on primary productivity changed with light intensity and zooplankton density and analysed pathways between temperature, diversity and productivity, elucidating direct and indirect effects of warming on primary productivity during the spring phytoplankton bloom. Our findings indicate that warming directly increased carbon specific primary productivity, which was more pronounced under low grazing pressure. On the other hand, primary productivity per unit water volume did not respond to increased temperature, because of a negative temperature effect on phytoplankton biomass. Moreover, primary productivity response to temperature changes depended on light limitation. Using path analysis, we tested whether temperature effects were direct or mediated by warming effects on phytoplankton diversity. Although phytoplankton species richness had a positive impact on both net primary productivity and carbon specific primary productivity - and evenness had a negative effect on net primary productivity - both richness and evenness were not affected by temperature. Thus, we suggest that diversity effects on primary productivity depended mainly on other factors than temperature like grazing, sinking or nutrient limitation, which themselves are temperature dependent.

  5. Effects of cryostorage on human sperm chromatin integrity.

    PubMed

    Fortunato, Adriana; Leo, Rita; Liguori, Francesca

    2013-11-01

    The integrity of sperm chromatin structure has proven to be of great importance for human fertility. In this study, we investigated whether sperm cryopreservation has an effect on nuclear DNA tertiary structure, (i.e. condensation), measured by aniline blue staining, in 103 male patients who required consultation for hypo-fertility. Sperm DNA damage was significantly higher in patients showing oligospermia and severe morphological abnormalities than in native sperm populations. Furthermore we observed that chromatin decondensation was related to the cryostorage technique and to the duration of storage. This increase in decondensation was highly significant (P < 0.01) immediately after cryopreservation and from 90 days of cryostorage onwards. The possible mechanisms involved in sperm chromatin cryoinjury and the need to incorporate new methods for testing sperm nuclear structure alteration into the routine spermiogram are discussed. PMID:22398023

  6. Increasing productivity in dental practice: the role of ancillary personnel.

    PubMed

    Guay, Albert H; Lazar, Vickie

    2012-01-01

    Dentistry has achieved substantial improvements in productivity which have the effect of making more care available at reasonable cost. Data are presented documenting trends in productivity. These are analyzed with respect to number of dentists, hours worked by dentists, and the use of ancillary personal in dental offices. There is strong evidence linking increased productivity to the use of ancillary personnel. The history of creation, recognition, and integration of ancillary personnel into dental practice is also presented. PMID:22856048

  7. Untapped opportunities for improving performance and increasing smelter production

    SciTech Connect

    Forberg, H.O.

    1996-10-01

    A review has been made of a large number of aluminum smelters concerning opportunities for improving performance and increasing production. Smelters have been grouped according to current efficiency. Opportunities for improvement of older and newer smelters are discussed. For older smelters to remain competitive and extend economic life, it is important to find new ways to increase production. These efforts have been going on for many years and the most successful producers have been able to stay viable. Opportunities are still available for many older facilities as further incremental increases of production wait to be harvested. Newer smelters are also interested in decreasing cost by increasing production. Even if the operating costs of newer plants are lower than those of older ones, it is important that newer plants make improvements that generate an acceptable rate of return on invested capital.

  8. Biodiversity increases the resistance of ecosystem productivity to climate extremes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It remains unclear whether biodiversity buffers ecosystems against extreme climate events, which are becoming increasingly frequent worldwide. Although early results suggested that biodiversity might provide both resistance and resilience (sensu rapid recovery) of ecosystem productivity to drought, ...

  9. Enhanced precipitation variability decreases grass- and increases shrub-productivity

    PubMed Central

    Gherardi, Laureano A.; Sala, Osvaldo E.

    2015-01-01

    Although projections of precipitation change indicate increases in variability, most studies of impacts of climate change on ecosystems focused on effects of changes in amount of precipitation, overlooking precipitation variability effects, especially at the interannual scale. Here, we present results from a 6-y field experiment, where we applied sequences of wet and dry years, increasing interannual precipitation coefficient of variation while maintaining a precipitation amount constant. Increased precipitation variability significantly reduced ecosystem primary production. Dominant plant-functional types showed opposite responses: perennial-grass productivity decreased by 81%, whereas shrub productivity increased by 67%. This pattern was explained by different nonlinear responses to precipitation. Grass productivity presented a saturating response to precipitation where dry years had a larger negative effect than the positive effects of wet years. In contrast, shrubs showed an increasing response to precipitation that resulted in an increase in average productivity with increasing precipitation variability. In addition, the effects of precipitation variation increased through time. We argue that the differential responses of grasses and shrubs to precipitation variability and the amplification of this phenomenon through time result from contrasting root distributions of grasses and shrubs and competitive interactions among plant types, confirmed by structural equation analysis. Under drought conditions, grasses reduce their abundance and their ability to absorb water that then is transferred to deep soil layers that are exclusively explored by shrubs. Our work addresses an understudied dimension of climate change that might lead to widespread shrub encroachment reducing the provisioning of ecosystem services to society. PMID:26417095

  10. Enhanced precipitation variability decreases grass- and increases shrub-productivity.

    PubMed

    Gherardi, Laureano A; Sala, Osvaldo E

    2015-10-13

    Although projections of precipitation change indicate increases in variability, most studies of impacts of climate change on ecosystems focused on effects of changes in amount of precipitation, overlooking precipitation variability effects, especially at the interannual scale. Here, we present results from a 6-y field experiment, where we applied sequences of wet and dry years, increasing interannual precipitation coefficient of variation while maintaining a precipitation amount constant. Increased precipitation variability significantly reduced ecosystem primary production. Dominant plant-functional types showed opposite responses: perennial-grass productivity decreased by 81%, whereas shrub productivity increased by 67%. This pattern was explained by different nonlinear responses to precipitation. Grass productivity presented a saturating response to precipitation where dry years had a larger negative effect than the positive effects of wet years. In contrast, shrubs showed an increasing response to precipitation that resulted in an increase in average productivity with increasing precipitation variability. In addition, the effects of precipitation variation increased through time. We argue that the differential responses of grasses and shrubs to precipitation variability and the amplification of this phenomenon through time result from contrasting root distributions of grasses and shrubs and competitive interactions among plant types, confirmed by structural equation analysis. Under drought conditions, grasses reduce their abundance and their ability to absorb water that then is transferred to deep soil layers that are exclusively explored by shrubs. Our work addresses an understudied dimension of climate change that might lead to widespread shrub encroachment reducing the provisioning of ecosystem services to society. PMID:26417095

  11. One-sided ejaculation of echidna sperm bundles.

    PubMed

    Johnston, S D; Smith, B; Pyne, M; Stenzel, D; Holt, W V

    2007-12-01

    We report for the first time an unusual ejaculatory mechanism in the short-beaked echidna in which each side of the bilaterally symmetrical, rosettelike glans penis is used alternately, with the other being shut down. This is unparalleled in mammals but is reminiscent of the use of hemipenes in squamate reptiles, providing further reproductive evidence of a sauropsidian lineage in the Monotremata. Further, we describe the occurrence of motile sperm bundles in ejaculated echidna semen and provide scanning electron micrographs of their morphology. Sperm bundling appears to confer increased sperm motility, which may provide the potential for sperm competition between males. PMID:18171162

  12. Sperm release pathway

    MedlinePlus Videos and Cool Tools

    ... top of the seminiferous tubules in the testes is the epididymis. The sperm migrate from of the ... vesicle are added. From the ampulla, seminal fluid is propelled forward through the ejaculatory ducts toward the ...

  13. Sperm release pathway

    MedlinePlus Videos and Cool Tools

    ... stored in this structure. The ejaculation process begins as the penis fills with blood and becomes erect. ... travel from the epididymis through the vas deferens, a muscular tube, which propels sperm forward through smooth ...

  14. Semiautomatic cold wire feeder systems increase GTA productivity

    SciTech Connect

    Richardson, M. )

    1995-01-01

    Often, the focus of attempts to increase GTA welding productivity is on studies to determine if justification exists for additional workstations, or for the investment in new fully automated dedicated welding fixtures. Often less costly and simpler solutions can bring about the necessary means to increase production rates and reduce operating costs. For short-run production applications, it is almost impossible to justify the substantial investment in a dedicated automatic fixture. Now, low cost GTA cold wire feeder systems are within the reach of even small shops. The paper views how cold wire equipment has been applied in several GTAW applications to improve results.

  15. Biodiversity increases the resistance of ecosystem productivity to climate extremes

    NASA Astrophysics Data System (ADS)

    Isbell, Forest; Craven, Dylan; Connolly, John; Loreau, Michel; Schmid, Bernhard; Beierkuhnlein, Carl; Bezemer, T. Martijn; Bonin, Catherine; Bruelheide, Helge; de Luca, Enrica; Ebeling, Anne; Griffin, John N.; Guo, Qinfeng; Hautier, Yann; Hector, Andy; Jentsch, Anke; Kreyling, Jürgen; Lanta, Vojtěch; Manning, Pete; Meyer, Sebastian T.; Mori, Akira S.; Naeem, Shahid; Niklaus, Pascal A.; Polley, H. Wayne; Reich, Peter B.; Roscher, Christiane; Seabloom, Eric W.; Smith, Melinda D.; Thakur, Madhav P.; Tilman, David; Tracy, Benjamin F.; van der Putten, Wim H.; van Ruijven, Jasper; Weigelt, Alexandra; Weisser, Wolfgang W.; Wilsey, Brian; Eisenhauer, Nico

    2015-10-01

    It remains unclear whether biodiversity buffers ecosystems against climate extremes, which are becoming increasingly frequent worldwide. Early results suggested that the ecosystem productivity of diverse grassland plant communities was more resistant, changing less during drought, and more resilient, recovering more quickly after drought, than that of depauperate communities. However, subsequent experimental tests produced mixed results. Here we use data from 46 experiments that manipulated grassland plant diversity to test whether biodiversity provides resistance during and resilience after climate events. We show that biodiversity increased ecosystem resistance for a broad range of climate events, including wet or dry, moderate or extreme, and brief or prolonged events. Across all studies and climate events, the productivity of low-diversity communities with one or two species changed by approximately 50% during climate events, whereas that of high-diversity communities with 16-32 species was more resistant, changing by only approximately 25%. By a year after each climate event, ecosystem productivity had often fully recovered, or overshot, normal levels of productivity in both high- and low-diversity communities, leading to no detectable dependence of ecosystem resilience on biodiversity. Our results suggest that biodiversity mainly stabilizes ecosystem productivity, and productivity-dependent ecosystem services, by increasing resistance to climate events. Anthropogenic environmental changes that drive biodiversity loss thus seem likely to decrease ecosystem stability, and restoration of biodiversity to increase it, mainly by changing the resistance of ecosystem productivity to climate events.

  16. Biodiversity increases the resistance of ecosystem productivity to climate extremes.

    PubMed

    Isbell, Forest; Craven, Dylan; Connolly, John; Loreau, Michel; Schmid, Bernhard; Beierkuhnlein, Carl; Bezemer, T Martijn; Bonin, Catherine; Bruelheide, Helge; de Luca, Enrica; Ebeling, Anne; Griffin, John N; Guo, Qinfeng; Hautier, Yann; Hector, Andy; Jentsch, Anke; Kreyling, Jürgen; Lanta, Vojtěch; Manning, Pete; Meyer, Sebastian T; Mori, Akira S; Naeem, Shahid; Niklaus, Pascal A; Polley, H Wayne; Reich, Peter B; Roscher, Christiane; Seabloom, Eric W; Smith, Melinda D; Thakur, Madhav P; Tilman, David; Tracy, Benjamin F; van der Putten, Wim H; van Ruijven, Jasper; Weigelt, Alexandra; Weisser, Wolfgang W; Wilsey, Brian; Eisenhauer, Nico

    2015-10-22

    It remains unclear whether biodiversity buffers ecosystems against climate extremes, which are becoming increasingly frequent worldwide. Early results suggested that the ecosystem productivity of diverse grassland plant communities was more resistant, changing less during drought, and more resilient, recovering more quickly after drought, than that of depauperate communities. However, subsequent experimental tests produced mixed results. Here we use data from 46 experiments that manipulated grassland plant diversity to test whether biodiversity provides resistance during and resilience after climate events. We show that biodiversity increased ecosystem resistance for a broad range of climate events, including wet or dry, moderate or extreme, and brief or prolonged events. Across all studies and climate events, the productivity of low-diversity communities with one or two species changed by approximately 50% during climate events, whereas that of high-diversity communities with 16-32 species was more resistant, changing by only approximately 25%. By a year after each climate event, ecosystem productivity had often fully recovered, or overshot, normal levels of productivity in both high- and low-diversity communities, leading to no detectable dependence of ecosystem resilience on biodiversity. Our results suggest that biodiversity mainly stabilizes ecosystem productivity, and productivity-dependent ecosystem services, by increasing resistance to climate events. Anthropogenic environmental changes that drive biodiversity loss thus seem likely to decrease ecosystem stability, and restoration of biodiversity to increase it, mainly by changing the resistance of ecosystem productivity to climate events. PMID:26466564

  17. Increasing children's ASL classifier production: a multicomponent intervention.

    PubMed

    Beal-Alvarez, Jennifer S; Easterbrooks, Susan R

    2013-01-01

    The Authors examined classifier production during narrative retells by 10 deaf and hard of hearing students in grades 2-4 at a day school for the deaf following a 6-week intervention of repeated viewings of stories in American Sign Language (ASL) paired with scripted teacher mediation. Classifier production, documented through a multiple-baseline-across-participants design, was followed by visual analysis and calculation of the percentage of non-overlapping data (Scruggs, Mastropieri, & Casto, 1987). Following the intervention, most students increased specific elements within their classifier production during narrative retells of stories they had watched and showed improved performance from pre- to postintervention measures. Picture support and fading of teacher mediation during retells variably affected classifier production. The results suggest that students may benefit from tailored intervention, including repeated viewings of ASL models paired with teacher mediation and possibly picture support, to increase classifier production during narrative retells. PMID:24133957

  18. Fenitrothion induced oxidative stress and morphological alterations of sperm and testes in male sprague-dawley rats

    PubMed Central

    Taib, Izatus Shima; Budin, Siti Balkis; Ghazali, Ahmad Rohi; Jayusman, Putri Ayu; Louis, Santhana Raj; Mohamed, Jamaludin

    2013-01-01

    OBJECTIVE: Fenitrothion residue is found primarily in soil, water and food products and can lead to a variety of toxic effects on the immune, hepatobiliary and hematological systems. However, the effects of fenitrothion on the male reproductive system remain unclear. This study aimed to evaluate the effects of fenitrothion on the sperm and testes of male Sprague-Dawley rats. METHODS: A 20 mg/kg dose of fenitrothion was administered orally by gavages for 28 consecutive days. Blood sample was obtained by cardiac puncture and dissection of the testes and cauda epididymis was performed to obtain sperm. The effects of fenitrothion on the body and organ weight, biochemical and oxidative stress, sperm characteristics, histology and ultrastructural changes in the testes were evaluated. RESULTS: Fenitrothion significantly decreased the body weight gain and weight of the epididymis compared with the control group. Fenitrothion also decreased plasma cholinesterase activity compared with the control group. Fenitrothion altered the sperm characteristics, such as sperm concentration, sperm viability and normal sperm morphology, compared with the control group. Oxidative stress markers, such as malondialdehyde, protein carbonyl, total glutathione and glutathione S-transferase, were significantly increased and superoxide dismutase activity was significantly decreased in the fenitrothion-treated group compared with the control group. The histopathological and ultrastructural examination of the testes of the fenitrothion-treated group revealed alterations corresponding with the biochemical changes compared with the control group. CONCLUSION: A 20 mg/kg dose of fenitrothion caused deleterious effects on the sperm and testes of Sprague-Dawley rats. PMID:23420164

  19. Mouse Sperm Membrane Potential Hyperpolarization Is Necessary and Sufficient to Prepare Sperm for the Acrosome Reaction*

    PubMed Central

    De La Vega-Beltran, Jose Luis; Sánchez-Cárdenas, Claudia; Krapf, Darío; Hernandez-González, Enrique O.; Wertheimer, Eva; Treviño, Claudia L.; Visconti, Pablo E.; Darszon, Alberto

    2012-01-01

    Mammalian sperm are unable to fertilize the egg immediately after ejaculation; they acquire this capacity during migration in the female reproductive tract. This maturational process is called capacitation and in mouse sperm it involves a plasma membrane reorganization, extensive changes in the state of protein phosphorylation, increases in intracellular pH (pHi) and Ca2+ ([Ca2+]i), and the appearance of hyperactivated motility. In addition, mouse sperm capacitation is associated with the hyperpolarization of the cell membrane potential. However, the functional role of this process is not known. In this work, to dissect the role of this membrane potential change, hyperpolarization was induced in noncapacitated sperm using either the ENaC inhibitor amiloride, the CFTR agonist genistein or the K+ ionophore valinomycin. In this experimental setting, other capacitation-associated processes such as activation of a cAMP-dependent pathway and the consequent increase in protein tyrosine phosphorylation were not observed. However, hyperpolarization was sufficient to prepare sperm for the acrosome reaction induced either by depolarization with high K+ or by addition of solubilized zona pellucida (sZP). Moreover, K+ and sZP were also able to increase [Ca2+]i in non-capacitated sperm treated with these hyperpolarizing agents but not in untreated cells. On the other hand, in conditions that support capacitation-associated processes blocking hyperpolarization by adding valinomycin and increasing K+ concentrations inhibited the agonist-induced acrosome reaction as well as the increase in [Ca2+]i. Altogether, these results suggest that sperm hyperpolarization by itself is key to enabling mice sperm to undergo the acrosome reaction. PMID:23095755

  20. Coevolutionary Feedbacks between Female Mating Interval and Male Allocation to Competing Sperm Traits Can Drive Evolution of Costly Polyandry.

    PubMed

    Bocedi, Greta; Reid, Jane M

    2016-03-01

    Complex coevolutionary feedbacks between female mating interval and male sperm traits have been hypothesized to explain the evolution and persistence of costly polyandry. Such feedbacks could potentially arise because polyandry creates sperm competition and consequent selection on male allocation to sperm traits, while the emerging sperm traits could create female sperm limitation and, hence, impose selection for increased polyandry. However, the hypothesis that costly polyandry could coevolve with male sperm dynamics has not been tested. We built a genetically explicit individual-based model to simulate simultaneous evolution of female mating interval and male allocation to sperm number versus longevity, where these two sperm traits trade off. We show that evolution of competing sperm traits under polyandry can indeed cause female sperm limitation and, hence, promote further evolution and persistence of costly polyandry, particularly when sperm are costly relative to the degree of female sperm limitation. These feedbacks were stronger, and greater polyandry evolved, when postcopulatory competition for paternity followed a loaded rather than fair raffle and when sperm traits had realistically low heritability. We therefore demonstrate that the evolution of allocation to sperm traits driven by sperm competition can prevent males from overcoming female sperm limitation, thereby driving ongoing evolution of costly polyandry. PMID:26913946

  1. Immune Activation Reduces Sperm Quality in the Great Tit

    PubMed Central

    Losdat, Sylvain; Richner, Heinz; Blount, Jonathan D.; Helfenstein, Fabrice

    2011-01-01

    Mounting an immune response against pathogens incurs costs to organisms by its effects on important life-history traits, such as reproductive investment and survival. As shown recently, immune activation produces large amounts of reactive species and is suggested to induce oxidative stress. Sperm are highly susceptible to oxidative stress, which can negatively impact sperm function and ultimately male fertilizing efficiency. Here we address the question as to whether mounting an immune response affects sperm quality through the damaging effects of oxidative stress. It has been demonstrated recently in birds that carotenoid-based ornaments can be reliable signals of a male's ability to protect sperm from oxidative damage. In a full-factorial design, we immune-challenged great tit males while simultaneously increasing their vitamin E availability, and assessed the effect on sperm quality and oxidative damage. We conducted this experiment in a natural population and tested the males' response to the experimental treatment in relation to their carotenoid-based breast coloration, a condition-dependent trait. Immune activation induced a steeper decline in sperm swimming velocity, thus highlighting the potential costs of an induced immune response on sperm competitive ability and fertilizing efficiency. We found sperm oxidative damage to be negatively correlated with sperm swimming velocity. However, blood resistance to a free-radical attack (a measure of somatic antioxidant capacity) as well as plasma and sperm levels of oxidative damage (lipid peroxidation) remained unaffected, thus suggesting that the observed effect did not arise through oxidative stress. Towards the end of their breeding cycle, swimming velocity of sperm of more intensely colored males was higher, which has important implications for the evolution of mate choice and multiple mating in females because females may accrue both direct and indirect benefits by mating with males having better quality sperm

  2. Increasing protein production by directed vector backbone evolution

    PubMed Central

    2013-01-01

    Recombinant protein production in prokaryotic and eukaryotic organisms was a key enabling technology for the rapid development of industrial and molecular biotechnology. However, despite all progress the improvement of protein production is an ongoing challenge and of high importance for cost-effective enzyme production. With the epMEGAWHOP mutagenesis protocol for vector backbone optimization we report a novel directed evolution based approach to increase protein production levels by randomly introducing mutations in the vector backbone. In the current study we validate the epMEGAWHOP mutagenesis protocol for three different expression systems. The latter demonstrated the general applicability of the epMEGAWHOP method. Cellulase and lipase production was doubled in one round of directed evolution by random mutagenesis of pET28a(+) and pET22b(+) vector backbones. Protease production using the vector pHY300PLK was increased ~4-times with an average of ~1.25 mutations per kb vector backbone. The epMEGAWHOP does not require any rational understanding of the expression machinery and can generally be applied to enzymes, expression vectors and related hosts. epMEGAWHOP is therefore from our point of view a robust, rapid and straight forward alternative for increasing protein production in general and for biotechnological applications. PMID:23890095

  3. Flow Cytometry Analysis Reveals That Only a Subpopulation of Mouse Sperm Undergoes Hyperpolarization During Capacitation1

    PubMed Central

    Escoffier, Jessica; Navarrete, Felipe; Haddad, Doug; Santi, Celia M.; Darszon, Alberto; Visconti, Pablo E.

    2015-01-01

    To gain fertilizing capacity, mammalian sperm should reside in the female tract for a period of time. The physiological changes that render the sperm able to fertilize are known as capacitation. Capacitation is associated with an increase in intracellular pH, an increase in intracellular calcium, and phosphorylation of different proteins. This process is also accompanied by the hyperpolarization of the sperm plasma membrane potential (Em). In the present work, we used flow cytometry to analyze changes in sperm Em during capacitation in individual cells. Our results indicate that a subpopulation of hyperpolarized mouse sperm can be clearly distinguished by sperm flow cytometry analysis. Using sperm bearing green fluorescent protein in their acrosomes, we found that this hyperpolarized subpopulation is composed of sperm with intact acrosomes. In addition, we show that the capacitation-associated hyperpolarization is blocked by high extracellular K+, by PKA inhibitors, and by SLO3 inhibitors in CD1 mouse sperm, and undetectable in Slo3 knockout mouse sperm. On the other hand, in sperm incubated in conditions that do not support capacitation, sperm membrane hyperpolarization can be induced by amiloride, high extracellular NaHCO3, and cAMP agonists. Altogether, our observations are consistent with a model in which sperm Em hyperpolarization is downstream of a cAMP-dependent pathway and is mediated by the activation of SLO3 K+ channels. PMID:25855261

  4. Sperm cryopreservation of a live-bearing fish, Xiphophorus couchianus: Male-to-male variation in post-thaw motility and production of F1 hybrid offspring☆

    PubMed Central

    Yang, Huiping; Hazlewood, Leona; Walter, Ronald B.; Tiersch, Terrence R.

    2015-01-01

    Fishes of the genus Xiphophorus are well-studied biomedical research models, and some species, such as X. couchianus, are currently listed as endangered in the wild. Sperm cryopreservation in these live-bearing fishes has begun recently. Thus far, live young have been produced with cryopreserved sperm only in one species (Xiphophorus helleri). In this study, the goal was to develop a practical protocol for sperm cryopreservation of Xiphophorus couchianus, and to produce live young with cryopreserved sperm. Sperm were collected by crushing of testis in Hanks’ balanced salt solution at an osmolality of 500 mOsmol/kg (HBSS500), and were cryopreserved with 14% glycerol (v/v) as cryoprotectant at a cooling rate of 20 °C/min from 5 to −80 °C in 250-μL French straws. For artificial insemination, samples were thawed at 40 °C for 5 s in a water bath, washed once using fresh HBSS500 by centrifuging at 1000 g for 5 min at 4 °C, concentrated into ~5 μL, and injected into virgin females of Xiphophorus maculatus. The inseminated females were monitored for 90 days for subsequent discharge of live young. Results from 2006 and 2007 showed considerable male-to-male variation in post-thaw motility (from 1 to 70%). Offspring were produced by cryopreserved sperm in two tanks (of three) at 36 and 66 days after insemination in 2007. Paternity was confirmed via phenotypes (body color) and genotypes (microsatellite genetic marker) of the hybrid offspring. Overall, a practical protocol for sperm cryopreservation and artificial insemination is provided to preserve X. couchianus, which is an important biomedical research model, and also currently listed as an endangered species in the International Union for Conservation of Nature (IUCN) red list. PMID:19027087

  5. Thyroxin Is Useful to Improve Sperm Motility

    PubMed Central

    Mendeluk, Gabriela Ruth; Rosales, Mónica

    2016-01-01

    Background The aim of this study was to evaluate the non-genomic action of thyroxin on sperm kinetic and its probable use to improve sperm recovery after applying an en- richment method like “swim-up” in comparison with the available one, pentoxifylline. Materials and Methods This is an experimental study. A total of 50 patients were re- cruited, followed by infertility consultation. Conventional sperm assays were performed according to World Health Organization criteria-2010 (WHO-2010). A Computer Aided Semen Analysis System was employed to assess kinetic parameters and concentrations. Number of the motile sperm recovered after preparation technique was calculated. Results Addition of T4 (0.002 µg/ml) to semen samples increased hypermotility at 20 minutes (control: 14.18 ± 5.1% vs. 17.66 ± 8.88%, P<0.03, data expressed as mean ± SD) and remained unchanged after 40 minutes. Significant differences were found in the motile sperm recovered after swim-up (control: 8.93×106 ± 9.52× 06vs. 17.20×106 ± 21.16×106, P<0.03), achieving all of the tested samples a desirable threshold value for artificial insemination outcome, while adding pentoxifylline increased the number of recovered sperm after swim-up in 60% of the studied cases. No synergism between two treatments could be determined. Conclusion We propose a new physiological tool to artificially improve insemination. The discussion opens windows to investigate unknown pathways involved in sperm ca- pacitation and gives innovative arguments to better understand infertility mechanisms. PMID:27441054

  6. Butterflies tailor their ejaculate in response to sperm competition risk and intensity

    PubMed Central

    Wedell, N.; Cook, P. A.

    1999-01-01

    Males of many insects eclose with their entire lifetime sperm supply and have to allocate their ejaculates at mating prudently. In polyandrous species, ejaculates of rival males overlap, creating sperm competition. Recent models suggest that males should increase their ejaculate expenditure when experiencing a high risk of sperm competition. Ejaculate expenditure is also predicted to vary in relation to sperm competition intensity. During high intensity, where several ejaculates compete for fertilization of the female's eggs, ejaculate expenditure is expected to be reduced. This is because there are diminishing returns of providing more sperm. Additionally, sperm numbers will depend on males' ability to assess female mating status. We investigate ejaculate allocation in the polyandrous small white butterfly Pieris rapae (Lepidoptera). Males have previously been found to ejaculate more sperm on their second mating when experiencing increased risk of sperm competition. Here we show that males also adjust the number of sperm ejaculated in relation to direct sperm competition. Mated males provide more sperm to females previously mated with mated males (i.e. when competing with many sperm) than to females previously mated to virgin males (competing with few sperm). Virgin males, on the other hand, do not adjust their ejaculate in relation to female mating history, but provide heavier females with more sperm. Although virgin males induce longer non-receptive periods in females than mated males, heavier females remate sooner. Virgin males may be responding to the higher risk of sperm competition by providing more sperm to heavier females. It is clear from this study that males are sensitive to factors affecting sperm competition risk, tailoring their ejaculates as predicted by recent theoretical models.

  7. Oxidative phosphorylation is essential for felid sperm function, but is substantially lower in cheetah (Acinonyx jubatus) compared to domestic cat (Felis catus) ejaculate.

    PubMed

    Terrell, Kimberly A; Wildt, David E; Anthony, Nicola M; Bavister, Barry D; Leibo, S P; Penfold, Linda M; Marker, Laurie L; Crosier, Adrienne E

    2011-09-01

    Compared with the normospermic domestic cat, sperm metabolic function is compromised in the teratospermic cat and cheetah, but the pathway(s) involved in this deficiency are unknown. Glycolysis is essential for sperm motility, yet it appears to function normally in spermatozoa of either species regardless of structural morphology. We conducted a comparative study to further understand the mechanisms of energy production in felid spermatozoa, with the hypothesis that oxidative phosphorylation is required for normal sperm function and is impaired in teratospermic ejaculates. Electroejaculates from both species were stained with MitoTracker to quantify mitochondrial membrane potential (MMP) or were incubated to assess changes in sperm function (motility, acrosomal integrity, and lactate production) after mitochondrial inhibition with myxothiazol. Sperm midpiece dimensions also were quantified. Sperm mitochondrial fluorescence (directly proportional to MMP) was ~95% lower in the cheetah compared with the normospermic and teratospermic cat, despite the cheetah having a 10% longer midpiece. In both species, MMP was increased 5-fold in spermatozoa with retained cytoplasm compared with structurally normal cells. Inhibition of oxidative phosphorylation impaired sperm function in both species, but a 100-fold higher inhibitor concentration was required in the cat compared with the cheetah. Collectively, findings revealed that oxidative phosphorylation was required for sperm function in the domestic cat and cheetah. This pathway of energy production appeared markedly less active in the cheetah, indicating a species-specific vulnerability to mitochondrial dysfunction. The unexpected, cross-species linkage between retained cytoplasmic droplets and elevated MMP may reflect increased concentrations of metabolic enzymes or substrates in these structures. PMID:21593479

  8. Calorie increase and water savings of redistributing global crop production

    NASA Astrophysics Data System (ADS)

    Davis, K. F.; Seveso, A.; Rulli, M. C.; D'Odorico, P.

    2015-12-01

    Human demand for crop production is expected to increase substantially in the coming decades as a result of population growth, richer diets and biofuel use. In order for food production to keep pace, unprecedented amounts of resources - water, fertilizers, energy - will be required. This has led to calls for 'sustainable intensification' in which yields are increased on existing croplands while seeking to minimize impacts on water and other agricultural resources. Recent studies have quantified aspects of this, showing that there is a large potential to improve crop yields and increase harvest frequencies to better meet human demand. Though promising, both solutions would necessitate large additional inputs of water and fertilizer in order to be achieved under current technologies. However, the question of whether the current distribution of crops is, in fact, the best for realizing maximized production has not been considered to date. To this end, we ask: Is it possible to increase calorie production and minimize water demand by simply growing crops where soil and climate conditions are best suited? Here we use maps of agro-ecological suitability - a measure of physical and chemical soil fertility - for 15 major food crops to identify differences between current crop distributions and where they can most suitably be planted. By redistributing crops across currently cultivated lands, we determine the potential improvement in calorie production as well as the associated change in water demand. We also consider what distribution of crops would maintain current calorie production while minimizing crop water demand. In doing all of this, our study provides a novel tool for improving crop calorie production without necessarily increasing resource demands.

  9. Production of fertile unreduced sperm by hybrid males of the Rutilus alburnoides complex (Teleostei, cyprinidae). An alternative route to genome tetraploidization in unisexuals.

    PubMed Central

    Alves, M J; Coelho, M M; Próspero, M I; Collares-Pereira, M J

    1999-01-01

    The hybrid minnow Rutilus alburnoides comprises diploid and polyploid females and males. Previous studies revealed that diploid and triploid females exhibit altered oogenesis that does not involve random segregation and recombination of the genomes of the two ancestors, constituting unisexual lineages. In the present study, we investigated the reproductive mode of hybrid males from the Tejo basin, using experimental crosses and flow cytometric analysis of blood and sperm. The results suggest that diploid hybrids produced fertile unreduced sperm, transmitting their hybrid genome intact to offspring. Triploid hybrids also produced unreduced sperm, but it was not possible to obtain data concerning their fertility. Finally, tetraploid hybrids produced fertile diploid sperm, which exhibited Mendelian segregation. Tetraploid R. alburnoides may reestablish biparental reproduction, as individuals of both sexes with the appropriate constitution for normal meiosis (two haploid genomes from each parental species) are likely to occur in natural populations. Tetraploids probably have arisen from syngamy of diploid eggs and diploid sperm produced by diploid hybrid males. Diploid hybrid males may therefore play a significant role in the dynamics of the complex, starting the evolutionary process that may ultimately lead to a new sexually reproducing species. PMID:9872966

  10. Intramale variation in sperm size: functional significance in a polygynous mammal

    PubMed Central

    Pintus, Eliana; Garde, José Julián

    2015-01-01

    Studies concerning the relationships between sperm size and velocity at the intraspecific level are quite limited and often yielded contradictory results across the animal kingdom. Intramale variation in sperm size may represent a meaningful factor to predict sperm velocity, due to its relationship with the level of sperm competition among related taxa. Because sperm phenotype is under post-copulatory sexual selection, we hypothesized that a reduced intramale variation in sperm size is associated with sperm competitiveness in red deer. Our results show that low variation in sperm size is strongly related to high sperm velocity and normal sperm morphology, which in turn are good predictors of male fertility in this species. Furthermore, it is well known that the red deer show high variability in testicular mass but there is limited knowledge concerning the significance of this phenomenon at intraspecific level, even though it may reveal interesting processes of sexual selection. Thereby, as a preliminary result, we found that absolute testes mass is negatively associated with intramale variation in sperm size. Our findings suggest that sperm size variation in red deer is under a strong selective force leading to increase sperm function efficiency, and reveal new insights into sexual selection mechanisms. PMID:26664807