Centrifugal countercurrent distribution (CCCD) in an aqueous two-phase system (TPS) is a resolute technique revealing sperm heterogeneity and for the estimation of the fertilizing potential of a given semen sample. However, separated sperm subpopulations have never been tested for their fertilizing ability yet. Here, we have compared sperm quality parameters and the fertilizing ability of sperm...

The N available after legumes is sufficient for maximum crop yields in many cropping systems. Fertilizing without accounting for the "extra" N mineralized from legume residues can contribute to high nitrate-N concentrations in the soil during crop production and increase nitrate-N leaching potential. Tillage practices also affect the physical, biological, and chemical nature of the soil, changi...

to study the effect of different fertilizing systems on macro and micro nutrients uptake by annual medic (medicago scutellata cv. robinson) an experiment was conducted under dry farming and irrigated conditions at two research stations (sararood dryland agricultural research institute and soil fertility research station in mahidasht) during 2009 growing season. the experimental treatments consi...

Many investigators maintain that spermatozoa that have initiated the acrosome reaction (AR) before reaching the surface of the egg's zona pellucida (ZP) are unable to bind and penetrate the ZP. A recent study has revealed that most fertilizing mouse spermatozoa initiate the AR before contacting the ZP. We found that acrosome-reacted spermatozoa collected from the perivitelline space of Cd9-null...

Hamster spermatozoa, collected from the caput and the cauda of the epididymis, are known to differ in their motility. They do not normally acquire fertilizing ability until they reach the proximal portion of the cauda epididymidis. The aim of the present investigation was to test the fertilizing capacity of spermatozoa from the caput epididymis after initiation. Sperm cells were incubated by ad...

Mouse and hamster spermatozoa from the cauda epididymidis were deposited into the female tract at various periods following ligation of the corpus epididymidis. It was found that the number of spermatozoa in the cauda epididymidis decreased sooner in the hamster than in the mouse but the initial decrease in fertilizing ability occurred much earlier in the mouse than in the hamster. The fertiliz...

Understanding the mechanisms by which the acrosome reaction is regulated is central to models of fertilization. This article reviews the relationship of the acrosome reaction detected in vitro to sperm function. Proteolytic enzymes in the acrosome digest through the zona pellucida allowing for sperm-oolemma fusion. When this process is impaired, either by lack of an acrosome or acrosomal dysfun...