Dwindling male fertility due to xenobiotics is of global concern. Accordingly, male reproductive toxicity assessment of xenobiotics through semen quality analysis in exposed males, and examining progeny production of their mates is critical. These assays, in part, are biased towards monogamy. Females soliciting multiple male partners (polyandry) is the norm in many species. Polyandry incites sp...

Fertilization is central to the survival and propagation of a species, however, the precise mechanisms that regulate the sperm's journey to the egg are not well understood. In nature, the sperm has to swim through the cervical mucus, akin to a microfluidic channel. Inspired by this, a simple, cost-effective microfluidic channel is designed on the same scale. The experimental results are support...

T HE maximum number of sperm which can be obtained by ejaculating domestic mammals apparently is less than the number produced by the testes (Amann and Almquist, 1962a, b; Kennelly and Foote, 1964; OrgebinCrist, 1968). The fate of unejaculated sperm is uncertain. Koefoed-Johnsen (1964) and Lino et al. (1967) showed that bulls and rams eliminate some sperm through micturition or masturbation. Ho...

There are two main reasons why sperm may be absent from semen. Obstructive azoospermia is the result of a blockage in the male reproductive tract; in this case, sperm are produced in the testicle but are trapped in the epididymis. Non-obstructive azoospermia is the result of severely impaired or non-existent sperm production. There are three different sperm-harvesting procedures that obstructiv...

Theory predicts that variation in body size within a population of simultaneous hermaphrodites should affect sex allocation, leading to individual differences in mating strategies and increased investment in female function with size. Small animals with fewer resources should invest proportionally more of their resources in male function than large animals, resulting in sperm displacement and p...

Compared with the normospermic domestic cat, sperm metabolic function is compromised in the teratospermic cat and cheetah, but the pathway(s) involved in this deficiency are unknown. Glycolysis is essential for sperm motility, yet it appears to function normally in spermatozoa of either species regardless of structural morphology. We conducted a comparative study to further understand the mecha...

Background: The objective of present study was to assess potential of DHR123 (dihydrorhodamine 123) fluorescent probe for measurement of H2O2 produced by human spermatozoa and comparing the results with DCFH-DA (2', 7'-dichlorodihydrofluorescein diacetate). Materials and Methods: Fluorescent intensity and percentage R123 and DCF positive sperm measured by flow cytometry. The suitable ...

Sperm competition typically favours an increased investment in testes, because larger testes can produce more sperm to provide a numerical advantage in competition with rival ejaculates. However, interspecific variation in testis size cannot be equated directly with variation in sperm production rate--which is the trait ultimately selected under sperm competition--because there are also differe...

To investigate the role of increased seminal leukocytes in enhancing reactive oxygen species (ROS) production by human spermatozoa.A prospective study. Male infertility clinic.Forty-eight infertile men. Standard semen analysis. Assessment of sperm nuclear DNA damage by sperm chromatin structure assay. Incubation of spermatozoa from nonleukocytospermic samples with blood neutrophils. Spontaneous...