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Extender
Kinds of Extender Terms modified by Extender Selected AbstractsThe Effects of Osmolality, Cryoprotectant and Equilibration Time on Striped Bass Morone saxatilis Sperm MotilityJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 3 2003Shuyang He Four experiments were designed to evaluate the effects of osmolality, cryoprotectant, and equilibration time on striped bass sperm motility. In the first experiment, solutions of NaCI or KCI with osmolalities ranging from 0 to 700 mmol/kg were tested on sperm activation. Over 60% of the sperm were activated by isotonic NaCI and KCI solutions with a treatment osmolality of 350 mmol/kg. Sperm remained motile until osmolality increased to 600 mmol/ kg. In the second and third experiments, Extenders 1, 2 and 3 with osmolalities of 350, 500, and 600 mmol/kg, respectively, were tested. Sperm samples stored in Extender 2 showed significantly higher (P 0.01) sperm motility after 10 min of exposure as well as greater (P < 0.01) post-thaw motility when compared to samples stored in Extenders 1 and 3. In the fourth experiment, two trials were carried out to evaluate the effects of cryoprotectant and equilibration time. In the first trial, methanol with a concentration of 5% and 10% yielded the highest (P < 0.05) sperm motility prior to freezing at all equilibration times examined. However, 5% DMSO yielded the highest (P < 0.01) post-thaw motility (38 ± 3.6%). DMSO with concentrations of 10% and 15% resulted in 17 ± 2.3% and 6 ± 1.0% post-thaw motility, respectively. Both methanol and DMA, at all concentrations tested, resulted in less than 10% post-thaw motility. In the second trial, four DMSO concentrations with three different equilibration times were examined. We observed a significant (P < 0.001) interaction effect between DMSO concentration and equilibration time. Post-thaw motility was significantly greater (P < 0.01) with a concentration of 5% DMSO at all equilibration times examined, compared to 1.25, 2.5, and 10% DMSO. An average post-thaw motility of 40 ± 2.9% was achieved after 10 min equilibration using 5% DMSO. [source] Protocol Optimization for Long-Term Liquid Storage of Goat Semen in a Chemically Defined ExtenderREPRODUCTION IN DOMESTIC ANIMALS, Issue 6 2009B-T Zhao Contents A specific problem in the preservation of goat semen has been the detrimental effect of seminal plasma on the viability of spermatozoa in extenders containing egg yolk or milk. The use of chemically defined extenders will have obvious advantages in liquid storage of buck semen. Our previous study showed that the self-made mZAP extender performed better than commercial extenders, and maintained a sperm motility of 34% for 9 days and a fertilizing potential for successful pregnancies for 7 days. The aim of this study was to extend the viability and fertilizing potential of liquid-stored goat spermatozoa by optimizing procedures for semen processing and storage in the mZAP extender. Semen samples collected from five goat bucks of the Lubei White and Boer breeds were diluted with the extender, cooled and stored at 5°C. Stored semen was evaluated for sperm viability parameters, every 48 h of storage. Data from three ejaculates of different bucks were analysed for each treatment. The percentage data were arcsine-transformed before being analysed with anova and Duncan's multiple comparison test. While cooling at the rate of 0.1,0.25°C/min did not affect sperm viability parameters, doing so at the rate of 0.6°C/min from 30 to 15°C reduced goat sperm motility and membrane integrity. Sperm motility and membrane integrity were significantly higher in semen coated with the extender containing 20% egg yolk than in non-coated semen. Sperm motility, membrane integrity and acrosomal intactness were significantly higher when coated semen was 21-fold diluted than when it was 11- or 51-fold diluted and when extender was renewed at 48-h intervals than when it was not renewed during storage. When goat semen coated with the egg yolk-containing extender was 21-fold diluted, cooled at the rate of 0.07,0.25°C/min, stored at 5°C and the extender renewed every 48 h, a sperm motility of 48% was maintained for 13 days, and an in vitro -fertilizing potential similar to that of fresh semen was maintained for 11 days. [source] Impacts of Alternative Manure Application Rates on Texas Animal Feeding Operations: A Macro Level Analysis,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2008E. Osei Abstract:, An integrated economic and environmental modeling system was developed for evaluating agro-environmental policies and practices implemented on large scales. The modeling system, the Comprehensive Economic and Environmental Optimization Tool-Macro Modeling System (CEEOT-MMS), integrates the Farm-level Economic Model (FEM) and the Agricultural Policy Environmental eXtender (APEX) model, as well as national databases and clustering and aggregation algorithms. Using micro simulations of statistically derived representative farms and subsequent aggregation of farm-level results, a wide range of agricultural best management practices can be investigated within CEEOT-MMS. In the present study, CEEOT-MMS was used to evaluate the economic and water quality impacts of nitrogen (N) and phosphorus (P) based manure application rates when implemented on all animal feeding operations in the State of Texas. Results of the study indicate that edge-of-field total P losses can be reduced by about 0.8 kg/ha/year or 14% when manure applications are calibrated to supply all of the recommended crop P requirements from manure total P sources only, when compared to manure applications at the recommended crop N agronomic rate. Corresponding economic impacts are projected to average a US$4,800 annual cost increase per farm. Results are also presented by ecological subregion, farm type, and farm size categories. [source] Leadership: a New Frontier in Conservation ScienceCONSERVATION BIOLOGY, Issue 4 2009JIM C. MANOLIS estrategia; influencia; liderazgo; manejo; política Abstract:,Leadership is a critical tool for expanding the influence of conservation science, but recent advances in leadership concepts and practice remain underutilized by conservation scientists. Furthermore, an explicit conceptual foundation and definition of leadership in conservation science are not available in the literature. Here we drew on our diverse leadership experiences, our reading of leadership literature, and discussions with selected conservation science leaders to define conservation-science leadership, summarize an exploratory set of leadership principles that are applicable to conservation science, and recommend actions to expand leadership capacity among conservation scientists and practitioners. We define 2 types of conservation-science leadership: shaping conservation science through path-breaking research, and advancing the integration of conservation science into policy, management, and society at large. We focused on the second, integrative type of leadership because we believe it presents the greatest opportunity for improving conservation effectiveness. We identified 8 leadership principles derived mainly from the "adaptive leadership" literature: recognize the social dimension of the problem; cycle frequently through action and reflection; get and maintain attention; combine strengths of multiple leaders; extend your reach through networks of relationships; strategically time your effort; nurture productive conflict; and cultivate diversity. Conservation scientists and practitioners should strive to develop themselves as leaders, and the Society for Conservation Biology, conservation organizations, and academia should support this effort through professional development, mentoring, teaching, and research. Resumen:,El liderazgo es una herramienta crítica para la expansión de la influencia de la ciencia de la conservación, pero los avances recientes en los conceptos y práctica del liderazgo son subutilizados por los científicos de la conservación. Más aun, en la literatura no hay una fundamentación conceptual ni definición de liderazgo en la ciencia de la conservación. Aquí nos basamos en nuestras experiencias de liderazgo, nuestra lectura de literatura sobre liderazgo y discusiones con líderes selectos de la ciencia de conservación para definir liderazgo para la ciencia de la conservación, resumir un conjunto exploratorio de principios de liderazgo aplicables a la ciencia de la conservación y recomendar acciones para expandir la capacidad de liderazgo entre los científicos y los practicantes de la conservación. Definimos dos tipos de liderazgo de la ciencia de la conservación: configuración de la ciencia de la conservación mediante investigación original, y avance hacia la integración del liderazgo en la ciencia de la conservación en la política, el manejo y la sociedad en general. Nos centramos en el segundo tipo de liderazgo porque consideramos que presenta la mejor oportunidad para mejorar la efectividad de la conservación. Identificamos ocho principios de liderazgo derivados principalmente de la literatura sobre "liderazgo adaptativo": reconocer la dimensión social del problema; alternar entre acción y reflexión frecuentemente; obtener y mantener atención; combinar fortalezas de múltiples líderes; extender el alcance mediante redes de relaciones; organizar el esfuerzo estratégicamente; evitar conflictos productivos y desarrollar la biodiversidad. Los científicos y los practicantes de la conservación deberían esforzarse para desarrollarse como líderes y la Sociedad para la Biología de la Conservación, las organizaciones de conservación y la academia deberían respaldar este esfuerzo mediante el desarrollo profesional, la tutoría, la enseñanza y la investigación. [source] Single layer centrifugation of stallion spermatozoa consistently selects the most robust spermatozoa from the rest of the ejaculate in a large sample sizeEQUINE VETERINARY JOURNAL, Issue 7 2010J. M. MORRELL Summary Reasons for performing study: An improvement in sperm quality after single layer centrifugation (SLC) has been seen in previous studies using small sample sizes (for example, n = 10 stallions). There is a need to investigate whether this improvement is repeatable over several breeding seasons with a larger number of stallions (n , 30 stallions). Objective: To make a retrospective analysis of the results of SLC performed on more than 250 sperm samples (176 ejaculates) from 31 stallions in 3 consecutive breeding seasons. Methods: Sperm quality (motility, proportion of morphologically normal spermatozoa and the proportion of spermatozoa with undamaged chromatin) was assessed before and after SLC. Results: All parameters of sperm quality examined were significantly better in sperm samples after SLC than in their unselected counterparts (P<0.001 for each parameter). The yield of spermatozoa obtained after SLC was influenced by the type of extender used and also by the concentration of spermatozoa in the original ejaculate, with fewer spermatozoa being recovered when the loading dose contained a high concentration of spermatozoa. The optimal concentration was approximately 100 × 106/ml. Sperm concentration in the samples loaded on to the colloid influenced the sperm yield while the type of semen extender affected sperm quality and survival. Furthermore, the scaled-up SLC method was found to be suitable for use with a range of ejaculates, with similar sperm kinematics being observed for standard and scaled-up preparations. Conclusions: SLC consistently improved the quality of stallion sperm samples from a large number of ejaculates. The method could be scaled-up, allowing larger volumes of ejaculate to be processed easily from a wide range of stallions. [source] A novel gene, ecl1+, extends the chronological lifespan in fission yeastFEMS YEAST RESEARCH, Issue 4 2008Hokuto Ohtsuka Abstract We have identified a novel gene from Schizosaccharomyces pombe that we have named ecl1+ (extender of the chronological lifespan). When ecl1+ is provided on a high-copy number plasmid, it extends the viability of both the ,sty1 MAP kinase mutant and the wild-type cells after entry into the stationary phase. ecl1+ encodes an 80-amino acid polypeptide that had not been annotated in the current database. The ecl1+ -mRNA increases transiently when the growth phase is changed from the log phase to the stationary phase. The Ecl1 protein is localized in the nucleus. Calorie restriction extends the chronological lifespan of wild-type and ,ecl1 cells but not ecl1+ -overproducing cells. The ,pka1 mutant shows little, if any, additional extension of viability when Ecl1 is overproduced. The ste11+ gene that is negatively controlled by Pka1 is up regulated when Ecl1 is overproduced. From these results we propose that the effect of Ecl1 overproduction may be mainly linked to and negatively affects the Pka1-dependent pathway. [source] Short-term storage of ova of common carp and tench in extendersJOURNAL OF FISH BIOLOGY, Issue 3 2001O. Linhart In a study of the effect of short-term storage on the hatching rate of common carp Cyprinus carpio and tench Tinca tinca ova in vitro in various extenders at 21° C under aerobic conditions, the best extender for 30 min storage for common carp appeared to be Dettlaff 1. This gave the same hatching rate as controls without extender (55%v. 56%). For 60 min storage of ova, the best extenders were Dettlaff 2 (24% hatching rate) and Dettlaff 3 (30%), but hatching was significantly lower than in the control (58%). In carp ovarian artificial fluid (CAF) extender, the hatching rate of common carp ova was also high after 10 min, but decreased to 12% after 30 min. In tench, the hatching rate of ova increased after 10 min storage in Dettlaff 5 extender (44%) compared to the control (41%) without extender. However, it was significantly lower after storage in Dettlaff 1, 2, 3, 4, 5 and CAF extenders for 20, 30 and 60 min, compared to controls. Malformations (10,50%) were observed in the tench second control groups without extender after 10, 20 and 30 min storage of ova. [source] EFFECT OF IONIZING RADIATION ON BEEF BOLOGNA CONTAINING SOY PROTEIN CONCENTRATEJOURNAL OF FOOD SAFETY, Issue 3 2001C.H. SOMMERS ABSTRACT Soy protein concentrate (SPC), an extender, is a common additive in ready-to-eat (RTE) meat products. SPC contains antioxidants that could potentially interfere with the ability of ionizing radiation to eliminate Listeria monocytogenes from RTE meat products. When L. monocytogenes was inoculated into cooked beef bologna emulsion containing 0, 1.75, or 3.5% SPC the gamma radiation D10 values, at radiation doses of 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 kGy, were 0.66, 0.68, and 0.71kGy, respectively. Soluble antioxidant power, as determined by the Ferric Reducing Antioxidant Power (FRAP) assay was 1958, 3572, and 5494 mol in bologna emulsion containing 0, 1.75 and 3.5% SPC, respectively. Soluble antioxidant power was not affected by ionizing radiation. SPC did not prevent ionizing radiation induced lipid oxidation as determined by Thiobarbituric Acid Reactive Substance (TBARS) assay. Hunter color analysis of both unirradiated and irradiated bologna slices containing SPC indicated decreased a value as a result of irradiation, while the addition of SPC helped maintain b-value and L-value. The inclusion of SPC did not represent a barrier to ionizing radiation pasteurization of fine emulsion sausages for the parameters examined. [source] A novel aromatic,aliphatic copolyester consisting of poly(1,4-dioxan-2-one) and poly(ethylene- co -1,6-hexene terephthalate): Preparation, thermal, and mechanical propertiesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 13 2010Jie Gong Abstract A novel multiblock aromatic,aliphatic copolyester poly(ethylene- co -1,6-hexene terephthalate)-copoly(1,4-dioxan-2-one) (PEHT-PPDO) was successfully synthesized via the chain-extension reaction of dihydroxyl teminated poly(ethylene- co -hexane terephthalate) (PEHT-OH) with dihydroxyl teminated poly(1,4-dioxan-2-one) (PPDO-OH) prepolymers, using toluene-2,4-diisocyanate as a chain extender. To produce PEHT-OH prepolymer with an appropriate melting point which can match the reaction temperature of PEHT-OH prepolymer with PPDO-OH prepolymer, 1,6-hexanediol was used to disturb the regularity of poly(ethylene terephthalate) segments. The chemical structures and molecular weights of PEHT-PPDO copolymers were characterized by 1H NMR, FTIR, and GPC. The DSC data showed that PPDO-OH segments were miscible well with PEHT-OH segments in amorphous state and that the crystallization of copolyester was predominantly contributed by PPDO segments. The TGA results indicated that the thermal stability of PEHT-PPDO was improved comparing with PPDO homopolymer. The novel aromatic,aliphatic copolyesters have good mechanical properties and could find applications in the field of biodegradable polymer materials. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2828,2837, 2010 [source] Synthesis and properties of segmented main-chain liquid-crystalline polyurethanes with a high aspect ratio mesogenic diol as a chain extenderJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 10 2002T. Padmavathy Abstract Main-chain liquid-crystalline polyurethanes were synthesized based on a high aspect ratio mesogenic diol (4-{[4-(6-hydroxyhexyloxy)-phenylimino]-methyl}-benzoic acid 4-{[4-(6-hydroxyhexyloxy)-phenylimino]-methyl}-phenyl ester) as a chain extender; polycaprolactone (PCL) diol soft segments of different number-average molecular weights (530, 1250, or 2000); and different diisocyanates, including 1,4-hexamethylene diisocyanate (HMDI), 4,4,-methylene bis(cyclohexyl isocyanate) (H12MDI), and 4,4,-methylene bis(phenyl isocyanate) (MDI). The structure of the polymers was confirmed with Fourier transform infrared spectroscopy, and differential scanning calorimetry and polarizing microscopy measurements were carried out to examine the liquid-crystalline and thermal properties of the polyurethanes, respectively. The mesogenic diol was partially replaced with 20,50 mol % PCL. A 20 mol % mesogen content was sufficient to impart a liquid crystalline property to all the polymers. The partial replacement of the mesogenic diol with PCL of various molecular weights, as well as the various diisocyanates, influenced the phase transitions and the occurrence of mesophase textures. Characteristic liquid-crystalline textures were observed when a sufficient content of the mesogenic diol was present. Depending on the flexible spacer length and the mesogenic content, grained and threadlike textures were obtained for the HMDI and H12MDI series polymers, whereas the polyurethanes prepared from MDI showed only grained textures for all the compositions. The polymers formed brittle films and could not be subjected to tensile tests. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1527,1538, 2002 [source] Solid polymer electrolytes III: Preparation, characterization, and ionic conductivity of new gelled polymer electrolytes based on segmented, perfluoropolyether-modified polyurethaneJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 4 2002Chi-Chang Chen Abstract New segmented polyurethanes with perfluoropolyether (PFPE) and poly(ethylene oxide) blocks were synthesized from a fluorinated macrodiol mixed with poly(ethylene glycol) (PEG) in different ratios as a soft segment, 2,4-toluene diisocyanate as a hard segment, and ethylene glycol as a chain extender. Fourier transform infrared, NMR, and thermal analysis [differential scanning calorimetry and thermogravimetric analysis (TGA)] were used to characterize the structures of these copolymers. The copolymer films were immersed in a liquid electrolyte (1 M LiClO4/propylene carbonate) to form gel-type electrolytes. The ionic conductivities of these polymer electrolytes were investigated through changes in the copolymer composition and content of the liquid electrolyte. The relative molar ratio of PFPE and PEG in the copolymer played an important role in the conductivity and the capacity to retain the liquid electrolyte solution. The copolymer with a 50/50 PFPE/PEG ratio, having the lowest decomposition temperature shown by TGA, exhibited the highest ionic conductivity and lowest activation energy for ion transportation. The conductivities of these systems were about 10,3 S cm,1 at room temperature and 10,2 S cm,1 at 70 °C; the films immersed in the liquid electrolyte with an increase of 70 wt % were homogenous with good mechanical properties. © 2002 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 486,495, 2002; DOI 10.1002/pola.10119 [source] Improved Cryopreservation of Sperm of Paddlefish (Polyodon spathula)JOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2006ÁKos Horváth Experiments were performed to improve protocols for sperm cryopreservation of paddlefish (Polyodon spathula), a species for which there has been limited study. The first experiment was conducted to investigate the effects of two extenders (modified Tsvetkova's extender: mT and modified Hanks' balanced salt solution: mHBSS) in combination with methanol (MeOH) and dimethyl sulfoxide in two concentrations (5 and 10%) on the postthaw motility and fertilization rates of cryopreserved sperm. The highest postthaw motility (85 ± 5%) was observed when sperm were frozen using mT extender with 10% MeOH as cryoprotectant. Extenders (P = 0.0018) and cryoprotectants (P = 0.0040) each had a significant effect on the postthaw motility of paddlefish sperm. The highest fertilization (80 ± 3%) was found when eggs were fertilized with sperm frozen with mT extender in combination with 10% MeOH. However, there was no significant difference among fertilization rates when MeOH was used as a cryoprotectant in either concentration or in combination with either mT or mHBSS extenders. In the second experiment, 4000 eggs were fertilized with the pooled contents of five straws of thawed sperm (total volume of 1.25 mL) using mT extender in combination with 5% MeOH, and hatch rates as high as 79 ± 5% were observed. A third experiment was also conducted to clarify the role of MeOH concentration; however, no significant difference was found among fertilization and hatch rates when either 5 or 10% MeOH was used as a cryoprotectant. These results suggest that MeOH is a safe and reliable cryoprotectant for freezing of paddlefish sperm and obtaining viable postthaw sperm for consistent fertilization and hatch rates. Further, this experimental protocol is relatively simple and applicable for commercial hatchery production of paddlefish. [source] Photocurable Shape-Memory Copolymers of , -Caprolactone and L -LactideMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 16 2010Minoru Nagata Abstract Biodegradable and photocurable block copolymers of , -caprolactone and L -lactide were synthesized by polycondensation of PLLA diol (,=,10,000,g,·,mol,1), PCL diol (,=,10,000,g,·,mol,1), and a chain extender bearing a coumarin group. The effect of copolymer composition on the thermal and mechanical properties of the photocured copolymers was studied by means of DSC and cyclic tensile tests. An increase in Young's modulus and a decrease in the tensile strain with increasing PLLA content was observed for the block copolymers. Block copolymers with high PCL content showed good to excellent shape-memory properties. Random copolymers exhibited Rf and Rr values above 90% at 45,°C for an extremely large tensile strain of 1,000%. [source] Effects of 2-hydroxypropyl-,-cyclodextrin and cholesterol on porcine sperm viability and capacitation status following cold shock or incubationMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 5 2006Hannah L. Galantino-Homer Abstract Porcine sperm are extremely sensitive to the damaging effects of cold shock. It has been shown that cholesterol-binding molecules, such as 2-hydroxypropyl-,-cyclodextrin (HBCD), improve post-cooling porcine sperm viability when added to an egg yolk-based extender, but also enhance sperm capacitation in other species. The objective of this study was to determine the effects of HBCD and cholesterol 3-sulfate (ChS) on porcine sperm viability and capacitation following cold shock or incubation under conditions that support capacitation using a defined medium. We report here that porcine sperm incubated in medium containing both HBCD and ChS have significantly improved viability following cold shock (10 min at 10°C) when compared to sperm incubated without HBCD or ChS, or with either component alone. Treatment with HBCD plus ChS also completely inhibited the increase in protein tyrosine phosphorylation induced by the cold shock treatment or by incubation for 3 hr under conditions that support capacitation. Two assays of sperm capacitation, the rate of calcium ionophore-induced acrosome reactions and chlortetracycline (CTC) staining, were not significantly altered by HBCD and ChS following cold shock. However, 3-hr incubation with HBCD plus ChS or with 1 mM ChS alone decreased the percentage of sperm undergoing the induced acrosome reaction without significantly affecting viability when compared to the control. These results indicate that the manipulation of sperm plasma membrane cholesterol content affects porcine sperm viability and capacitation status and could therefore be useful to protect sperm from cold shock during cryopreservation by improving viability without promoting premature capacitation. Mol. Reprod. Dev. © 2006 Wiley-Liss, Inc. [source] Composites of carbon nanofibers and thermoplastic polyurethanes with shape-memory properties prepared by chaotic mixingPOLYMER ENGINEERING & SCIENCE, Issue 10 2009Guillermo A. Jimenez Composites of carbon nanofibers (CNFs), oxidized carbon nanofibers (ox-CNFs), and shape-memory thermoplastic polyurethane (TPU) were prepared in a chaotic mixer and their shape-memory properties evaluated. The polymer was synthesized from 4,4,-diphenylmethane diisocyanate, 1,4-butanediol chain extender, and semicrystalline poly(,-caprolactone) diol soft segments. The shape-memory action was triggered by both conductive and resistive heating. It was found that soft segment crystallinity and mechanical reinforcement by nanofibers produced competing effects on shape-memory properties. A large reduction in soft segment crystallinity in the presence of CNF and stronger mechanical reinforcement by well-dispersed ox-CNF determined the shape-memory properties of the respective composites. It was found that the maximum shape recovery force, respectively, 3 and 4 MPa, was obtained in the cases of 5 and 1 wt% CNF and ox-CNF, respectively, compared with ,1.8 MPa for unfilled TPU. The degree of soft segment and hard segment phase separation and thermal stability of the composites were analyzed. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers. [source] Poly(ester-urethane)s synthesized using polyoxalate diolsPOLYMER ENGINEERING & SCIENCE, Issue 2 2005Hideho Tanaka Amorphous poly(ester-urethane)s (PEUs) were synthesized by reacting polyoxalate diols (PODs), which are oligoester diols prepared from condensation polymerization of dimethyl oxalate (DMO) and alkane diols, with 4, 4,-diphenylmethane diisocyanate (MDI) and propylene diamine (PDA), a chain extender. Their structure,property relationships were studied, mainly focused on effects of molecular weight and alkylene chain length of the POD. The synthesized PEUs were buried in compost soil at 30°C and incubated to conveniently evaluate their biodegradability. Their hydrolytic characteristics were also examined, and what made poly(oxalate-urethane) (POU) biodegradable was discussed. Poly(oxalate carbonate-urethane) (POCU), which can be produced adding a polycarbonate diol (PCD) into the POD and then copolymerizing them with DMO, provided biodegradable polyurethanes with mechanical properties appropriate for practical uses. In addition, the microstructure of these copolyurethanes was characterized. POLYM. ENG. SCI., 45:163,173, 2005. © 2005 Society of Plastics Engineers. [source] Synthesis and properties of room temperature curable trimethoxysilane-terminated polyurethane and their dispersionsPOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 8 2007Sankaraiah Subramani Abstract The purpose of this research is to study the synthesis and characterization of stable aqueous dispersions of externally chain extended polyurethane/urea compositions terminated by hydrolyzable or hydrolyzed trialkoxysilane groups incorporated through secondary amino groups. These dispersions with excellent storage stability are substantially free from organic solvents which cure to water and solvent resistant, tough, scratch resistant, preferably light stable (non-yellowing) silylated polyurethane (SPU) films. The films were characterized by FT-IR, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), tensile strength and water contact angle measurements, nanoindentation, gel content, water and xylene swellability tests. The properties of the films were discussed and correlated in detail by changing length of soft segment, diisocyanates, NCO/OH ratio and chain extender, ethylenediamine (EDA). From the results, it was found that the particle size and viscosity are lower whereas the gel content and thermal stability are higher for SPUs. Modulus, hardness and tensile properties of SPU films are superior compared to EDA-PU film. Higher water contact angle and residual weight percentage of SPU films confirm silylation of PU by [3-(phenylamino)propyl]trimethoxysilane (PAPTMS). Increase in NCO/OH ratios consumes more quantity of PAPTMS which makes PU with superior mechanical properties. Higher PAPTMS content in SPU results in effective crosslinking of the functional silanol groups formed by hydrolysis reaction of trimethoxysilane groups. Overall, SPUs synthesized at 1.4 NCO/OH ratio using Poly-(oxytetramethylene)glycol (PTMG)-2000 and isophorone diisocyanate (or) toluene-2,4-diisocyanate have excellent properties compared to SPUs prepared using PTMG-1000 and at 1.2 and 1.6 NCO/OH ratios. SPUs prepared at 1.6 NCO/OH ratio are brittle due to higher crosslinking density. In addition, the crosslinking density of the films can be modified through silane end-group modification to produce SPUs with a wide range of physical properties. Copyright © 2007 John Wiley & Sons, Ltd. [source] Effect of Docosahexaenoic Acid on Quality of Cryopreserved Boar Semen in Different BreedsREPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2010K Kaeoket Contents During the cryopreservation process, the level of polyunsaturated fatty acids, especially docosahexaenoic acid (DHA), in the sperm plasma membrane decreases significantly because of lipid peroxidation, which may contribute to sperm loss quality (i.e. fertility) of frozen,thawed semen. The aim of this study was to investigate the effect of supplementation of DHA (fish oil) in freezing extender II on frozen,thawed semen quality. Semen from 20 boars of proven motility and morphology, were used in this study. Boar semen was split into four groups, in which the lactose,egg yolk (LEY) extender used to resuspend the centrifuged sperm pellet was supplemented with various levels of fish oil to reach DHA level of 1X (group I, control, no added fish oil), 6X (group II), 12X (group III) and 18X (group IV). Semen solutions were frozen by using a controlled rate freezer. After cryopreservation, frozen semen was thawed and evaluated for progressive motility, viability by using SYBR-14/Ethidiumhomodimer-1 (EthD-1) staining and acrosome integrity by using FITC-PNA/EthD-1 staining. There was a significantly higher (p < 0.001) percentage of progressive motility, viability and acrosome integrity in DHA (fish oil) supplemented groups than control group. Generally, there seemed to be a dose-dependent effect of DHA, with the highest percentage of progressive motility, viability and acrosome integrity in group-III. In conclusion, supplementation of the LEY extender with DHA by adding fish oil was effective for freezing boar semen as it resulted in higher post-thaw plasma membrane integrity and progressive motility. [source] Effect of N-acetyl-L-cysteine Supplementation in Semen Extenders on Semen Quality and Reactive Oxygen Species of Chilled Canine SpermatozoaREPRODUCTION IN DOMESTIC ANIMALS, Issue 2 2010AJ Michael Contents The objective of this study was to evaluate the quality of chilled dog semen processed with extenders containing various concentrations of N-acetyl-L-cysteine (NAC). Ejaculates from five dogs were collected, pooled and evaluated for concentration, motility, rapid steady forward movement (RSF-movement), viability, acrosomal integrity and by the hypo-osmotic swelling test (HOST). In addition, superoxide anion (O2 -,) production, hydroxyl radicals (OH,) and total reactive oxygen species (tROS) were determined. The pool was divided into five aliquots, which were diluted to a final concentration of 66.66 × 106 spermatozoa/ml with Tris-glucose-egg yolk extender containing one of the following concentrations of NAC (0, 0.5, 1, 2.5 or 5 mm). The semen aliquots were chilled and preserved at 4°C. Semen quality was evaluated after rewarming at 72 h. Sperm motility was significantly higher with the 0.5 mm concentration compared with the control group (p = 0.001). Rapid steady forward movement was higher with the 0.5 and 1 mm concentrations compared with the control and 5 mm group (p < 0.001). Viability and HOST percentages were not significantly altered. Compared with the control, the 5 mm concentration showed significantly reduced percentages of spermatozoa with normal acrosomes (p = 0.049). None of the ROS values at 72 h were significantly affected by the presence of NAC in semen extenders, although all NAC concentrations showed lower O2 -, and OH, values compared with the control. Only the concentrations of 1 and 5 mm inhibited the significant increase of tROS values after 72 h, compared with the fresh semen value. In conclusion, NAC supplementation of semen extenders is beneficial to semen motility of canine spermatozoa during chilling with the 0.5 mm concentration being the most effective, although no significant ROS inhibition was observed at 72 h. [source] Protocol Optimization for Long-Term Liquid Storage of Goat Semen in a Chemically Defined ExtenderREPRODUCTION IN DOMESTIC ANIMALS, Issue 6 2009B-T Zhao Contents A specific problem in the preservation of goat semen has been the detrimental effect of seminal plasma on the viability of spermatozoa in extenders containing egg yolk or milk. The use of chemically defined extenders will have obvious advantages in liquid storage of buck semen. Our previous study showed that the self-made mZAP extender performed better than commercial extenders, and maintained a sperm motility of 34% for 9 days and a fertilizing potential for successful pregnancies for 7 days. The aim of this study was to extend the viability and fertilizing potential of liquid-stored goat spermatozoa by optimizing procedures for semen processing and storage in the mZAP extender. Semen samples collected from five goat bucks of the Lubei White and Boer breeds were diluted with the extender, cooled and stored at 5°C. Stored semen was evaluated for sperm viability parameters, every 48 h of storage. Data from three ejaculates of different bucks were analysed for each treatment. The percentage data were arcsine-transformed before being analysed with anova and Duncan's multiple comparison test. While cooling at the rate of 0.1,0.25°C/min did not affect sperm viability parameters, doing so at the rate of 0.6°C/min from 30 to 15°C reduced goat sperm motility and membrane integrity. Sperm motility and membrane integrity were significantly higher in semen coated with the extender containing 20% egg yolk than in non-coated semen. Sperm motility, membrane integrity and acrosomal intactness were significantly higher when coated semen was 21-fold diluted than when it was 11- or 51-fold diluted and when extender was renewed at 48-h intervals than when it was not renewed during storage. When goat semen coated with the egg yolk-containing extender was 21-fold diluted, cooled at the rate of 0.07,0.25°C/min, stored at 5°C and the extender renewed every 48 h, a sperm motility of 48% was maintained for 13 days, and an in vitro -fertilizing potential similar to that of fresh semen was maintained for 11 days. [source] Effect of Different Concentrations of Ascorbic Acid on Motility, Membrane Integrity and Chromatin Status of Frozen-Thawed Canine Spermatozoa Within Six Hours of Storage at 37°CREPRODUCTION IN DOMESTIC ANIMALS, Issue 2009K Eulenberger Contents The aim of this study was to examine comprehensively the effect of ascorbic acid (Asc) on frozen-thawed canine semen. Pooled ejaculates (n = 10) were assessed for quality with a computer-assisted sperm analyser (CASA). After centrifugation, the semen was divided into four aliquots (A,D) of which three were diluted with Uppsala 1 extender (v/v) containing different concentrations of Asc (B: 6.8 mmol/l; C: 13 mmol/l; D: 27 mmol/l). One group without Asc served as control (A). Subsequently, dilution samples were treated and cryopreserved as described previously (Theriogenology 66, 2006, 173). After thawing, samples were stored at 37°C for 1, 3 and 6 h, then examined for quality (CASA, flow cytometry, sperm chromatin structure assay; SCSA). Staining for flow cytometry was performed with FITC-PNA and propidium iodide (Reproduction 128, 2004, 829). The SCSA was performed with both Tris-NACL-EDT buffer (TNE)- and Tris-fructose-citrate buffer (TFC). In the Asc-supplemented groups, percentages of progressively motile sperm (P) were significantly lower than in the control group (A 1 h: 56.6 ± 9.8, 6 h: 18 ± 4.5; B 1 h: 51.2 ± 11.8, 6 h: 13.6 ± 5; C 1 h: 41 ± 16.2, 6 h: 11.2 ± 6.1; D 1 h: 37 ± 15.2, 6 h: 8.6 ± 5; p < 0.01), whereas, the percentages of intact cells without acrosome reactions did not differ between groups (p > 0.05). Furthermore, there were no significant differences between TNE- and TFC-samples, for ,T, for SD of ,T or for comp ,T [comp ,T: TCF-A: 2.5 ± 1.7%, TNE-A: 3.4 ± 3.2%; TCF-D: 2.5 ± 2%, TNE-D: 3.3 ± 4.3%; p > 0.05]. However, samples diluted with both extenders correlated concerning ,T, but not comp ,T. We therefore recommend using TNE-buffer for SCSA with cryopreserved canine semen. In addition, the average ,T values did not differ significantly between the controls and all other groups (TNE-A: 380.2 ± 89.1; TNE-D: 338.1 ± 137.4; p > 0.05). It can be concluded that addition of Asc to cryoextender does not increase quality of frozen-thawed canine semen. [source] Influence of Ascorbic Acid and Glutathione Antioxidants on Frozen-Thawed Canine SemenREPRODUCTION IN DOMESTIC ANIMALS, Issue 2009JC Monteiro Contents Poor sperm viability post-thaw has resulted in constant research into methods of cryopreservation of canine semen. One factor that may be involved in poor viability is sperm oxidative stress caused by excessive formation of reactive oxygen species. The present study was performed in order to evaluate the effect of different concentrations of ascorbic acid (AA) and glutathione (Glu) added to an extender for the freeze-thawing of dog sperm. Semen from five mature dogs was collected and frozen in two studies. Prior to and after freezing, sperm motility, morphology and membrane status were examined. In addition, sperm motility was examined up to 120 min after thawing to evaluate thermo-resistance. In study I, semen was collected twice from each dog. On both occasions, semen was divided into three aliquots: control, Glu 1 mm and Glu 5 mm. In study II, semen was collected twice and divided into three aliquots; control, AA 50 ,m and AA 250 ,m. Initial sperm motility was significantly higher in sperm diluted with AA 50 ,m; sperm longevity, however, measured by a thermal-resistance test (TRT), was higher for Glu treatments. Higher concentration of Glu produced significant improvement in TRT and membrane status, whereas higher concentration of AA had a negative impact in sperm longevity. Antioxidant supplementation to semen freezing extenders improved semen quality post-thaw. Moreover, Glu had the most beneficial effect when supplemented at 5 mm. [source] Effects of Oxygen Exposure and Gentamicin on Stallion Semen Stored at 5 and 15°CREPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2008S Price Contents This study was undertaken to investigate the effects of storage of stallion semen in a defined milk protein extender at 5 and 15°C under either anaerobic or aerobic conditions, with or without addition of the antibiotic gentamicin. Semen samples were collected from eight fertile stallions and stored for 96 h (day 0,4) and assessed daily for motility, velocity and membrane integrity (viability) using a CASA system. Samples for bacteriology assessment were taken on day 2 of storage. No significant (p > 0.05) differences in motility, velocity or viability were observed between treatments on days 0,2. On days 3 and 4, semen stored without gentamicin at 5°C had a significantly (p < 0.05) better semen quality compared with storage at 15°C without gentamicin, irrespective of oxygen exposure. On days 3 and 4, motility and velocity were greater in samples stored at 15°C with gentamicin, compared with the corresponding treatments without antibiotic (p < 0.05). This effect was also evident for viability on day 4. The decline in semen quality observed at 15°C most likely resulted from the effect of bacterial growth. Bacterial growth was the greatest in samples stored at 15°C without gentamicin, under both anaerobic and aerobic conditions (p < 0.05). Bacterial growth was inhibited by adding of gentamicin at 15°C, which accordingly reduced the decline in semen quality. Addition of antibiotic to samples stored at 5°C had no significant effect on any parameter analysed. In conclusion, storage at 15°C can be achieved by using an extender containing the antibiotic gentamicin. Storage at 5°C tended to maintain better semen quality irrespective of oxygen exposure, and did not necessitate an antibiotic treatment. [source] Post-thaw Survival and Longevity of Bull Spermatozoa Frozen with an Egg Yolk-based or Two Egg Yolk-free Extenders after an Equilibration Period of 18 hREPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2007R Muiño Contents The aim of the present study was to determine the suitability of using two egg yolk-free commercial extenders, Andromed® and Biociphos Plus®, as compared with the Tris-egg yolk based diluent Biladyl®, for the cryopreservation of bull spermatozoa when the freezing protocol involved holding the extended semen at 4°C for 18 h before the freezing. Six ejaculates from each of 10 Holstein bulls were collected by using artificial vagina. The ejaculates were evaluated for volume, sperm concentration and motility, divided in to three equal volumes, and diluted, respectively, with the three extenders as specified above. Extended semen was equilibrated for 18 h at 4°C and frozen in 0.25-ml straws. After thawing, 100- ,l aliquots of semen were labelled with SYBR-14, PI and PE-PNA (Phycoerythrin-conjugated Peanut agglutinin) and analysed by flow cytometry at 0, 3, 6 and 9 h after incubation at 37°C. A General Lineal Model procedure for repeated measures was used to determine the effects of extender, bull, replicate and the interaction between them, on sperm viability and acrosomal integrity. Semen samples frozen with Biladyl® showed higher (p < 0.001) sperm survival after 0 h (47.9%) and 9 h (30.3%) of incubation than those frozen with Andromed® (38.5% and 17.3%, after 0 and 9 h respectively) or Biociphos Plus® (34.9% and 21.6%, after 0 and 9 h respectively). The bull and replicate had significant effects (p < 0.001) on both sperm viability and acrosomal integrity, but the interactions between bull and extender and between replicate and extender were not significant. It was concluded that, when holding the semen overnight before freezing, the use of Biladyl® results in higher sperm survival and longevity than the use of Andromed® or Biociphos Plus®. [source] Reduction of Oxidative Stress in Bovine Spermatozoa During Flow Cytometric SortingREPRODUCTION IN DOMESTIC ANIMALS, Issue 1 2007P Klinc Contents The goal of the study was to investigate the effect of antioxidant supplementation on the quality of frozen-thawed flow cytometrically sorted bull spermatozoa. Twelve ejaculates from two Holstein Friesian bulls were sorted according to the Beltsville Sperm Sexing Technology. Each ejaculate was divided into three parts and processed as (i) unsorted controls, (ii) according to a standard sorting protocol and (iii) in the presence of different antioxidants (S-AO). Cooling and freezing of the samples were performed in the same way for all three groups, except that antioxidants were added to the TRIS-egg-yolk freezing extender for those semen samples that were already sorted in the presence of antioxidants. The semen quality in frozen-thawed samples was determined by morphology analysis immediately after thawing, motility estimation in a thermo-resistance test after 0, 6, 12 and 24 h incubation at 37°C and Fluorescein isothiocyanate conjugated PNA/propidium iodide (FITC-PNA/PI) staining after 0, 12 and 24 h of incubation at 37°C. There was a significantly higher (p < 0.05) percentage of motile spermatozoa in S-AO samples in comparison to unsorted frozen-thawed control at 0, 6 and 24 h after thawing and compared with normally sorted samples at all times after thawing. The percentage of damaged acrosomes was significantly lower (p < 0.05) in S-AO samples than in the unsorted controls (20.8 ± 6.9% vs 30.3 ± 12.0%). The percentage of morphologically abnormal spermatozoa in this group was significantly lower (p < 0.05) than in the unsorted controls and normally sorted samples (25.8 ± 5.2%, 36.0 ± 12.5% and 35.1 ± 7.4%, respectively). Analysis of frozen-thawed spermatozoa with FITC/PI revealed no significant difference in membrane integrity at 0 and 12 h after sorting, but after 24 h of incubation the S-AO samples had a significantly higher (p < 0.001) percentage of spermatozoa with intact membranes in comparison to unsorted controls and normally sorted semen (40.7 ± 6.3%, 7.8 ± 4.7% and 7.4 ± 4.6%, respectively). The percentage of acrosome-reacted spermatozoa was significantly lower (p < 0.05) in the S-AO samples than in the unsorted controls (14.1 ± 7.5%, 23.4 ± 5.4% and 28.8 ± 6.3% vs 25.9 ± 14.4%, 38.5 ± 16.7% and 79.8 ± 4.1%, for 0, 12 and 24 h after thawing, respectively) and in comparison to normally sorted semen 24 h after thawing (67.3 ± 10.0%). This study demonstrates the highly protective effects of antioxidants on the quality of flow cytometrically sorted frozen-thawed bull spermatozoa. [source] OC2 Seasonality Affects on Sperm Motility Kinematic Parameters of Murciano-Granadina BucksREPRODUCTION IN DOMESTIC ANIMALS, Issue 2006D Abdelwahab Four Murciano-Granadina (M-G) bucks were used to study the effect of season (autumn and spring) on semen motility kinematic parameters. Ejaculates (n = 31/season) were collected twice weekly with an artificial vagina and diluted with Tris-based extender (1 : 10). Average path velocity (VAP) and linearity (LIN) were evaluated using a Computer-Assisted Semen Analysis (CASA system). A FASTCLUS procedure was applied to separate spermatozoa into subpopulations based on their motility characteristics. The mean values of both motility kinematic parameters were significantly (p < 0.05) higher in spring than in autumn. Four different motile sperm subpopulations (SP) were identified. In autumn, SP 1 (with a frequency of 17.1%) showed a VAP of 41.5 ,m/s and a LIN of 38.3%. SP 2 (37.2%) a VAP of 70.2 ,m/s and a LIN of 46.1% SP 3 (19.1%) a VAP of 93.3 ,m/s and a LIN of 31.6%. Finally, SP 4 (26.6%) a VAP of 111.8 ,m/s and a LIN of 67.2%. In spring, SP 1 (21.1%) a VAP of 46.3 ,m/s and a LIN of 50.1%. SP 2 (39.6%) a VAP of 77.0 ,m/s and a LIN of 68.6%. SP 3 (17%) a VAP of 87.8 ,m/s and a LIN of 40.2%. Finally, SP 4 (22.3%) a VAP of 112.3 ,m/s and a LIN of 70.4%. In conclusion, the season of ejaculate collection has a significant effect on sperm motility kinematic parameters of M-G bucks. [source] Comparative Study on Five Different Commercial Extenders for Boar SemenREPRODUCTION IN DOMESTIC ANIMALS, Issue 1 2004P Vyt Contents Increasing interest in a longer preservation of diluted boar sperm raises questions in the field concerning the choice of the extender. The aim of this study was to evaluate the longevity of boar sperm extended in currently used commercial semen extenders. Three long-term extenders and two short-term extenders were compared for different semen quality parameters that can be assessed under routine laboratory conditions. Sperm morphology, motility, pH and bacteriological contamination were investigated during a 7-day period. The number of dead spermatozoa did not differ significantly among the extenders (p > 0.05). Sperm motility was not only related with storage period but most of all with pH, especially in long-term extenders. Differences between the different extenders were prominent (p < 0.05); the sperm preserved in only one long-term extender showed good motility during the whole test period. In all cases, the pH of the extended semen increased by 0.3,0.5 in the first days of storage and was significantly correlated with a decrease in motility. Bacteriological quality had no significant influence on motility or pH of the semen. In conclusion, we can state that in both short-term extenders and in only one long-term extender, sperm longevity, as evaluated by the parameters used in this study, was sufficient during the preservation period. To preserve the quality of diluted boar semen during long-term storage, the choice of the long-term extender is important. In addition, the monitoring of the pH of extended boar semen in our study emphasizes the importance of the buffering capacity of semen extenders. [source] ORIGINAL RESEARCH,PEYRONIE'S DISEASE: Use of Penile Extender Device in the Treatment of Penile Curvature as a Result of Peyronie's Disease.THE JOURNAL OF SEXUAL MEDICINE, Issue 2 2009Results of a Phase II Prospective Study ABSTRACT Introduction., Pilot experiences have suggested that tension forces exerted by a penile extender may reduce penile curvature as a result of Peyronie's disease. Aim., To test this hypothesis in a Phase II study using a commonly marketed brand of penile extender. Methods., Peyronie's disease patients with a curvature not exceeding 50° with mild or no erectile dysfunction (ED) were eligible. Fifteen patients were required to test the efficacy of the device assuming an effect size of >0.8, consistent with an "important" reduction in penile curvature. Changes in penile length over baseline and erectile function (EF) domain scores of the International Index of Erectile Function (IIEF) constituted secondary end points. Main Outcome Measures., Patients were counselled on the use of the penile extender for at least 5 hours per day for 6 months. Photographic pictures of the erect penis and measurements were carried out at baseline, at 1, 3, 6, and 12 months (end of study). The IIEF-EF domain scores were administered at baseline and at the end of study. Treatment satisfaction was assessed at end of study using a nonvalidated institutional 5-item questionnaire. Results., Penile curvature decreased from an average of 31° to 27° at 6 months without reaching the effect size (P = 0.056). Mean stretched and flaccid penile length increased by 1.3 and 0.83 cm, respectively at 6 months. Results were maintained at 12 months. Overall treatment results were subjectively scored as acceptable in spite of curvature improvements, which varied from "no change" to "mild improvement." Conclusions., In our study, the use of a penile extender device provided only minimal improvements in penile curvature but a reasonable level of patient satisfaction, probably attributable to increased penile length. The selection of patients with a stabilized disease, a penile curvature not exceeding 50°, and no severe ED may have led to outcomes underestimating the potential efficacy of the treatment. Gontero P, Di Marco M, Giubilei G, Bartoletti R, Pappagallo G, Tizzani A, and Mondaini N. Use of penile extender device in the treatment of penile curvature as a result of Peyronie's disease. Results of a phase II prospective study. J Sex Med 2009;6:558,566. [source] Litter Characteristics of Gilts Artificially Inseminated with Transforming Growth Factor-,AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 3 2006Michelle Rhodes Problem, Semen is a rich source of transforming growth factor- , (TGF- ,) and it has been proposed that this molecule promotes embryonic survival by modifying immune responses to promote tolerance toward paternal antigens and by inducing release of cytokines that promote embryonic development. The role of TGF- , was tested using pigs by evaluating whether its addition to washed sperm improves conceptus survival and fetal growth. Methods of study, At estrus, gilts were artificially inseminated twice at 12-hr intervals with 100 mL of either washed semen resuspended in a commercial semen extender supplemented with 2 mg/mL of gelatin or washed semen in the same extender containing 65 ng/mL of TGF- ,1. Three boars were used as semen donors. At day 80 (±4 days) of gestation, gilts were sacrificed and reproductive tracts harvested. Results, Treatment had no effect (P > 0.10) on total or live fetuses per litter, implantation rate, fetal survival or percentage of corpora lutea resulting in live fetuses at day 80. Insemination with TGF- ,1 also did not affect total or average fetal weight or total placental weight. There was a tendency (P = 0.09) for average placental weight of live fetuses to be lower for pregnancies established in gilts treated with TGF- ,1. Also, placental efficiency (mass of fetus/mass of placenta) was greater (P < 0.05) for pregnancies established in gilts treated with TGF- ,1. The high fertility in control gilts (80% implantation rate and 11.5 live fetuses per litter) is indicative that soluble seminal factors are not necessary for the establishment of pregnancy. Conclusions, Within the ranges tested, concentration of TGF- , in the fluid phase of the inseminate is not an important determinant of conceptus survival or fetal and placental growth to day 80 of gestation in the pig. [source] Metabolic evaluation of cooled equine spermatozoaANDROLOGIA, Issue 2 2010A. B. Vasconcelos Summary Microscopy has been used in the routine evaluation of sperm metabolism. Nevertheless, it has limited capacity to preview male fertility. As calorimetry may be used to evaluate directly the metabolic activity of a biological system, the aim of this study was to use microcalorimetry as an additive method for sperm metabolism evaluation of cooled equine semen. Two ejaculates of four stallions were collected and motility, viability (eosin 3%) and membrane functional integrity (hyposmotic swelling test) of spermatozoa were evaluated. Sperm samples were processed following different protocols and the metabolism of these samples was accessed by calorimetry. Centrifugation is part of some of these processing protocols and although this procedure has been deleterious for sperm viability and plasma membrane integrity, no decrease in sperm motility was observed. Microcalorimetry was capable of detecting the positive effect of re-suspending the sperm pellet with Kenney extender. Thus, the use of microcalorimetry offered additional information for equine sperm metabolism evaluation and was efficient in detecting important information from sperm cell metabolism. [source] | ||||||||||||||||||||||||||||||||||||||||