Sephadex filtration as successful alternative to density-gradient centrifugation procedures for ram sperm selection with improved kinetics

Abstract

Density-gradients centrifugation (DGC) and filtration columns (FC) are used to separate deformed or dead sperm, debris, and other cells that may negatively affect the fertilizing capacity of sperm in fresh, chilled and frozen/thawed semen. The present study was conducted to evaluate the suitability of DGC (BoviPure®, Percoll® and Accudenz®) and FC (Sephadex G-15®) sperm selection procedures for fresh-extended and cold-stored ram semen by assessment of post-treatment sperm quality variables. Twenty normospermic ejaculates from ten adult Merino rams were used. Sperm concentration of recovered cells was greater (P < 0.001) after BoviPure treatment than other procedures in both fresh and cold semen. With the Sephadex method, there were more desirable values than with use of DGC procedures in several sperm motility variables measured by using the CASA system. In non-refrigerated semen samples, the percentage of progressive sperm motility (%PSM) after Sephadex filtration was greater (P < 0.05) than after BoviPure treatment; the straightline velocity (VSL) value after Sephadex filtration was greater (P < 0.01) than after Accudenz treatment; the amplitude of lateral head displacement (ALH) after Sephadex and Accudenz treatment was less than non-filtered semen (P< 0.001) and after Percoll (P < 0.01) and BoviPure (P < 0.05) treatments. In cold-stored semen samples, the %PSM after Sephadex filtration was greater than non-filtered (P < 0.05) semen and after BoviPure (P < 0.05), Percoll (P < 0.05) and Accudenz (P < 0.001) treatments. It is concluded that Sephadex column filtration can be used to select ram sperm in non-refrigerated and cooled semen, because percentage progressively motile sperm and some other sperm motility characteristics are greater with use of this techniques as compared with use of DGC methods.

Perspectives of nanotechnology in male fertility and sperm function

“…These techniques also allow to recover spermatozoa from sub-optimal ejaculates from animals of high genetic values. In literature, several techniques have been developed to achieve this purpose and have been tested in farm animals: among others, swim up assay [23], [24], [25]; density gradient centrifugation [23], [25], [26], [27], filtration through columns [28], [29], [30], [31], [32] and single layer centrifugation (SLC) [33], [34], [35]. Although these procedures greatly improve motility and functional parameters especially in post-thaw semen, on the other side they lead to a reduction in the concentration of the insemination doses due to their variable recovery rates, they are time consuming and add costs and labour to the standard procedures of semen handling and storage [36].…”

Dissection-independent production ofPlasmodiumsporozoites from whole mosquitoes

“…As an alternative to density gradients, we also tested whether rapid gel filtration with a Sephadex-based spin-column (5 min) could replace Accudenz, mirroring a method used with bovine sperm purification ( 51 ). Use of Sephadex resulted in sporozoite losses of <10% compared with Accudenz, which resulted in sporozoite losses of up to 50%.…”

State-of-the-Art and Prospective of Nanotechnologies for Smart Reproductive Management of Farm Animals

“…These techniques may be especially helpful in recovering spermatozoa from sub-optimal ejaculates from animals of high genetic values but, moreover, removal of dead spermatozoa is highly beneficial, because of the negative effects on motility and membrane integrity of live spermatozoa [22]. The main techniques for semen purification in farm animals are density gradient centrifugation [23], swim-up assay [24], column purification [25] and single layer centrifugation [26]. Although these techniques significantly improve the motility and functional parameters of sperm cells in semen doses, especially in post-thawing semen, their efficiency is still limited by variable recovery rates (leading to low sperm concentration in semen doses), long run time and increased costs and labor [27].…”