background: sperm preparation is a fundamental step in art and attempt for developing new methods to be continued. objective: to evaluate the efficacy of upstream method for separation of human spermatozoa and its effects on sperm parameters including: motility morphology and concentration. materials and methods: semen samples from 17 men who referred to infertility clinic for evaluating their ...

the purpose of this study was to evaluate the efficiency of intracytoplasmic sperm injection (icsi) and piezo-assisted sperm injection after pretreatment with calcium ionophore (cai) on the mouse embryo development. methods: in this study, the conventional icsi and piezo-icsi procedures were used. the efficacy of the methods was examined after mouse matured oocytes were fertilized with or witho...

Sperm conjugation occurs when two or more sperm physically unite for motility or transport through the female reproductive tract. In many muroid rodent species, sperm conjugates have been shown to form by a single, conspicuous apical hook located on the sperm head. These sperm "trains" have been reported to be highly variable in size and, despite all the heads pointing in roughly the same direc...

BACKGROUND Cystatin C (CST3), a cysteine protease inhibitor in seminal plasma, is expressed in animal uteri. However, its expression in the human female reproductive tract and its effect on human sperm capacitation are unclear. METHODS The cellular localization of CST3 was observed using immunohistochemistry. The binding of CST3 to sperm was examined using immunocytochemistry. Sperm motility ...

Sperm competition theory predicts that when males are certain of sperm competition, they should decrease sperm investment in matings with an increasing number of competing ejaculates. How males should allocate sperm when competing with differently sized ejaculates, however, has not yet been examined. Here, we report the outcomes of two models assuming variation in males' sperm reserves and male...

Interspecific variation in sperm size is enigmatic, but generally assumed to reflect species-specific trade-offs in selection pressures. Among passerine birds, sperm length varies sevenfold, and sperm competition risk seems to drive the evolution of longer sperm. However, little is known about factors favouring short sperm or constraining the evolution of longer sperm. Here, we report a compara...

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Sperm chemoattraction in invertebrates can be sufficiently robust that one can place a pipette containing the attractive peptide into a sperm suspension and microscopically visualize sperm accumulation around the pipette. Sperm chemoattraction in vertebrates such as frogs, rodents and humans is more difficult to detect and requires quantitative assays. Such assays are of two major types - assay...

This study was aimed at determining the blood serum testosterone level and its relationship with scrotal circumference and physical characteristics of semen in Nili-Ravi buffalo bulls. Semen samples were collected weekly from three buffalo bulls of 14 years age for 12 weeks and were evaluated for physical characteristics i.e. ejaculatory volume, sperm motility, sperm concentration, pH and sperm...

I n the recent literature, several interesting articles have been published using the zona pellucdia (ZP)-bound sperm for intracytoplasmic sperm injection (ICSI) to enhance embryo quality, implantation and clinical pregnancy rates. The three studies were performed independently in different ART clinics. In the test group, patients’ sibling immature (either germinal vesicle (GV) or metaphase I) ...