Polyspermy is pathological in mammals (Austin & Walton, i960), but is uncommon because mechanisms exist which prevent its occurrence. In the sheep, cow, pig and other species, after penetration by the first spermatozoon, the zona pellucida undergoes a change, the 'zona reaction', which bars further spermatozoa from passing through the zona, but still allows them to enter it. Unlike the eggs of ...

Experiment was conducted to evaluate the effect of different levels of egg yolk for coating and storing spermatozoa. Ejaculates were collected from four rams. In each session, second ejaculates (n=4) were collected in a tube containing 1 mL coating buffers which were prepared by 10, 15 or 20% egg yolk plus Tris-fructose. Samples were pooled, centrifuged and the supernatant removed in the labora...

two glycoprotein sperm-specific antigens of testicular origin and twelve seminal plasma antigens which coated the spermatozoa during passage through the reproductive tract. Two of the sperm-coating antigens originated in the testis, two in the epididymis and eight above the level of the vas deferens. Relationships between sperm-coating antigens and capacitation, and sperm-coating antigens and p...

It is generally known that spermatozoa aquire the capacity for fertilization during passage through the proximal region of the epididymal duct and are then stored in the distal region of the duct (BEDFORD, 1975 ; HAMILTON, 1975). The mouse epididymal duct has been divided into five segments (I-V) by light microscopy ; Segments I, II and III constitute the head of the epididymis, Segment IV the ...

background: ubiquitin, an 8.5 kda peptide that marks other proteins for proteasomal degradation, tags defective sperm dur­ing epididymal passage. thus, sperm ubiquitination is a universal marker for sperm defects and can be used as a sperm func­tion test. the objective of the present study was to examine the relationships between sperm ubiquiti­nation and clinical se­men parameters, using simpl...

In four experiments, the effects of pre-thaw delay, method of thawing, temperature of thawing solution and pellet volume on acrosome morphology and moti l i ty of" boar spermatozoa frozen by the pellet method were examined. Holding the frozen pellets for 0, 1.5, 3 or 4.5 min in a Styrofoam container before transferring them into the thawing solution resulted in maximum post-thaw percentages of ...

The present report was designed to study the macrophage role and their association with percentage of spermatozoa showing DNA native, morphologically normal sperm and occurrence of antibody-coated spermatozoa. Human sperm samples from 31 patients were used in this study. All samples were evaluated for standard semen parameters according to World Health Organization criteria. The sperm heads wit...

Although epithelial-like somatic cells have been previously isolated from semen, cell proliferation rates were low. Culture of whole semen samples resulted in loss of potentially valuable spermatozoa. The aims of the present study were to: (1) isolate somatic cells from semen, while preserving sperm viability, and (2) optimize in vitro culture conditions for semen-derived epithelial cells. Dens...

For assisted reproduction technologies (ART), numerous techniques were developed to isolate spermatozoa capable of fertilizing oocytes. While early methodologies only focused on isolating viable, motile spermatozoa, with progress of ART, particularly intracytoplasmic sperm injection (ICSI), it became clear that these parameters are insufficient for the identification of the most suitable sperma...