Semen cryopreservation and sperm freezing has a long history of over 65 years. However, embryo freezing and oocyte cryopreservation in human infertility has a shorter history up to 40 years. Embryo and oocyte freezing had a tremendous progress and development in past four decades so it improved from slow freezing procedure with less than 10% survival rate at beginning to vitrification procedure...

38 fresh ejaculates were examined, of which 23 were cryopreserved in three diluents differing in concentration of glycerol and examined after thawing. For each ejaculate we established the concentration, motility, speed of sperm, percentage of live sperm and the morphological image of the ejaculate using routine laboratory diagnosis and SQA parameters at the initial value and after a 120-minute...

Bats are mammals of the order Chiroptera, which represents about 20% of all mammalian species worldwide. Bats have evolved various reproductive strategies, such as delayed sperm maturation, sperm storage, delayed fertilization, delayed implantation and delayed development. The strategies of delayed sperm maturation allow female bats, especially hibernating species, to reproduce successfully. Al...

Polyspermy is a major puzzle in reproductive biology. In some taxa, multiple sperm enter the ovum as part of the normal fertilization process, whereas in others, penetration of the ovum by more than one sperm is lethal. In birds, several sperm typically enter the germinal disc, yet only one fuses with the female pronucleus. It is unclear whether supernumerary sperm play an essential role in the...

Abstract:  The optimum dose of UV irradiation to produce gynogenesis rainbow trout, Oncorhynchus mykiss with emphasis of Hertwing effect and photoreactivation (PR) was investigated. For this purpose, the sperm of rainbow trout were inadiated with UV at 2010±200 µw.cm-2 intensity in different alternatives of 0, 1, 3, 5, 8, 10, 15, 20, 25, 35 and 45 minutes and allowed to fertilize normal ova; th...

Cryopreservation of spermatozoa plays a significant role in reproductive medicine and fertility preservation. Chicken egg yolk is used as an extender in cryopreservation of human spermatozoa using glycerol egg yolk citrate (GEYC) buffered medium. Even though 50% survival of spermatozoa is generally achieved with this method, the risk of high levels of endotoxins and transmission pathogens from ...

Müllerian inhibiting substance (MIS) has recently been implicated in multiple cellular functions including promotion of cell survival, but the receptor(s) and signaling pathways involved remain elusive. We have investigated the possibility of YWK-II protein, previously shown to interact physically with MIS and G(o) protein, being a receptor mediating the cell survival effect of MIS. In YWK-II-o...

Tumor necrosis factor (TNF), formerly known as Tumor necrosis factor alpha is now regarded as a natural component of the mammalian seminal plasma (SP). Although not completely clarified, its functions in the SP have been associated with paradoxal roles, such as sperm survival in the female genital tract, while at high levels negatively affect sperm survival and fertility potential. Recently, it...

Agricultural chemicals such as neonicotinoid insecticides are believed to be one important factor responsible for the recent reduction in health of pollinating insects like western honeybee Apis mellifera. However, effects neonicotinoids on male (drone) remain severely understudied. We examined first time multidimensional field-realistic concentrations two common (thiamethoxam and clothianidin)...