Lesions in the normal expression of sperm motility are associated with certain types of male infertility. Therefore, an understanding of the signal transduction pathways regulating sperm motility will be an important part of our understanding of the mechanisms underlying these types of male infertility. In this connection, the regulation of sperm fiagellar motility by second messengers is a rap...

Sperm-zona adhesion is an essential event in mammalian fertilization, failure of which causes sterility. However, the molecular mechanisms involved in this process are still poorly understood. It has been suggested by few laboratories studying gamete interaction that acrosomal molecules are implicated in sperm-zona pellucida adhesion prior to the acrosome reaction (AR). Zonadhesin, a sperm-spec...

We propose a novel automatic tracking system capable of tracking fast-moving, small objects under extreme conditions by using high-speed visual feedback for assessing sperm chemotaxis. The system shows remarkable performance and versatility, good enough for practical use in biology. Experimental results showed that we successfully achieved continuous stable tracking of swimming ascidian spermat...

This work assesses the present knowledge on Pacific oyster sperm biology in comparison to two marine fish species (turbot and seabass) whose sperm characteristics are well described. Sperm morphology mainly differs by the presence of an acrosome in Pacific oyster which is absent in both fish species. In turbot as in Pacific oyster, a sperm ‘maturation process’ along the genital tract is observe...

Crustaceans are a morphologically, physiologically and ecologically highly diverse animal group and correspondingly diverse are their reproductive characteristics. They have evolved structural specialities with respect to penis construction, sperm form, sperm storage, fertilization and brood care. Unique in the animal kingdom are safety lines that safeguard hatching and first molting. Further c...

Success in cryopreserving stallion semen has been very variable. Several different freezing regimes have been published. However, because extenders and procedures used in each regime have differed, direct comparison of these techniques has been very difficult, and controlled studies comparing different techniques have not been reported. A number of different factors affect sperm cryosurvival. I...

Sperm selection is essential to assisted reproductive technology (ART), influencing treatment outcomes and the health of offspring. The fundamental challenge of sperm selection is dictated by biology: a heterogeneous population of ~10(8) sperm per milliliter with a short lifetime in vitro. However, conventional sperm selection approaches result in less than 50% improvement in DNA integrity. Her...

The influence of epigenetic modifications on reproduction and on the function of male germ cells has been thoroughly demonstrated. In particular, aberrant DNA methylation levels in sperm have been associated with abnormal sperm parameters, lower fertilization rates and impaired embryo development. Recent reports have indicated that human sperm might be epigenetically heterogeneous and that abno...