Spermatozoa from C57BL/6NNia mice (7- and 25-month-old males that produced offspring and 25-month-old males incapable of producing offspring which either mated or did not mate after being paired for 1 month with proven-fertile females) were tested in in-vitro fertilization studies. The 7-month-old males fertilized the largest number of oocytes (80-86%) in vitro and 79% of them subsequently deve...

Globozoospermia is a severe form of teratozoospermia characterized by round-headed spermatozoa with an absent acrosome, an aberrant nuclear membrane and midpiece defects. Globozoospermia is diagnosed by the presence of 100% round-headed spermatozoa on semen analysis, and patients with this condition are absolutely infertile. The objective of this study was to investigate the differences in prot...

BACKGROUND Sodium arsenite can impair male reproductive function by inducing oxidative stress. Silymarin is known as a potent antioxidant. OBJECTIVE This study was performed to investigate if silymarin can prevent the adverse effect of sodium arsenite on ram sperm viability, motility and mitochondrial membrane potential. MATERIALS AND METHODS Epidydimal spermatozoa obtained from ram were di...

Ejaculated mammalian spermatozoa contain a complex yet specific population of mRNA. However, the possible roles that mRNA has in early zygotic and embryonic development remain unclear. We found that Dby mRNA is selectively retained in capacitated mouse spermatozoa, and is transferred into the oocyte during fertilization by reverse transcription-polymerase chain reaction even though no DBY prote...

OBJECTIVE To study the resistance of human spermatozoa to cryoinjury in repeated cycles of thaw-refreezing by using the fast liquid nitrogen vapor method. MATERIALS AND METHODS Semen specimens were obtained from sixteen normal and oligozoospermic individuals who required disposal at the sperm bank. Five of them had testicular cancer. Specimens were thawed and an aliquot was removed for analys...

BACKGROUND Spermatozoa have to traverse the cumulus oophorus before fertilization in vivo. Evidence suggests that the cumulus oophorus plays an important role in the fertilization process. We describe the establishment of a capillary-cumulus oophorus model with which to study the action of cumulus mass on the function of human spermatozoa. METHODS Human cumulus oophorus was aspirated into a g...

BACKGROUND Globozoospermia is a severe form of teratozoospermia (incidence < 0.1%) in infertile men that is characterized by round headed sperm and acrosomeless in semen. OBJECTIVE To compare the semen parameters, protamine deficiency, and apoptosis in ejaculated spermatozoa between globozoospermic and normozoospermic men. MATERIALS AND METHODS Thirty six semen samples were divided into two...

Spermatozoa of several mammalian species were studied by means of high-speed cinematography and electron microscopy. Three types of motile patterns were observed in mouse spermatozoa. The first type involved an asymmetrical beat which seemed to propel the sperm in circular paths. The second type involved rotation of the sperm and appeared to allow them to maintain straight paths. In the third t...

Taking advantage of conditions that allow spermatogenesis in vitro, the timing and sequence of morphological changes leading from the primary spermatocyte to the spermatozoon is described by light and electron microscopy . Together with previous studies, this allows a detailed description of the nuclear, cytoplasmic, and membrane changes occurring during spermatozoan morphogenesis . By comparis...

Spermatozoa after being deposited in the female reproductive tract spend a considerable time in this foreign environment prior to fertilization of the oocyte. Chang and Austin independently observed1,2 that this time spent by the spermatozoa in the female tract is not consequential but a necessary event in the life cycle of the male gamete, and Austin2 first called this maturation period of spe...