Time filter

Source Type

Balao da Silva C.M.,Laboratory of Equine Reproduction and Equine Spermatology | Ortega Ferrusola C.,Laboratory of Equine Reproduction and Equine Spermatology | Morillo Rodriguez A.,Laboratory of Equine Reproduction and Equine Spermatology | Gallardo Bolanos J.M.,Laboratory of Equine Reproduction and Equine Spermatology | And 6 more authors.
Animal Reproduction Science | Year: 2013

At present, the only repeatable means of selecting the sex of offspring is the Beltsville semen sorting technology using flow cytometry (FC). This technology has reached commercial status in the bovine industry and substantial advances have occurred recently in swine and ovine species. In the equine species, however, the technology is not as well developed. To better understand the changes induced in stallion spermatozoa during the sorting procedure, pooled sperm samples were sorted: sperm motility and kinematics were assessed using computer assisted sperm analysis, sperm membrane integrity was assessed using the YoPro-1 assay, while plasmalemmal stability and lipid architecture were assessed using Merocyanine 540/SYTOX green and Annexin-V, respectively. Lipid peroxidation was also investigated with the probe Bodipy581/591-C11. All assays were performed shortly after collection, after incubation and after sex sorting using FC. In order to characterize potential molecular mechanisms implicated in sperm damage, an apoptosis protein antibody dot plot array analysis was performed before and after sorting. While the percentage of total motile sperm remained unchanged, sex sorting reduced the percentages of progressive motile spermatozoa and of rapid spermatozoa as well as curvilinear velocity (VCL). Sperm membranes responded to sorting with an increase in the percentage of YoPro-1 positive cells, suggesting the sorted spermatozoa had a reduced energy status that was confirmed by measuring intracellular ATP content. © 2013 Elsevier B.V..

Balao da Silva C.M.,Laboratory of Equine Reproduction and Equine Spermatology | Ortega-Ferrusola C.,Laboratory of Equine Reproduction and Equine Spermatology | Morrell J.M.,Swedish University of Agricultural Sciences | Rodriguez Martinez H.,Linkoping University | Pena F.J.,Laboratory of Equine Reproduction and Equine Spermatology
Reproduction in Domestic Animals | Year: 2016

Contents: To date, the only repeatable method to select spermatozoa for chromosomal sex is the Beltsville sorting technology using flow cytometry. Improvement of this technology in the equine species requires increasing awareness of the modifications that the sorting procedure induces on sperm intactness. Oxidative stress is regarded as the major damaging phenomenon, and increasing evidence regards handling of spermatozoa - including sex sorting - as basic ground for oxidative damage. The aim of this study was to disclose whether the flow cytometric sorting procedure increases the production of reactive oxygen species (ROS), and to identify if ROS production relates to DNA damage in sorted spermatozoa using specific flow cytometry-based assays. After sorting, oxidative stress increased from 26% to 33% in pre- and post-incubation controls, to 46% after sex sorting (p < 0.05). Proportions of DNA fragmentation index post-sorting were approximately 10% higher (31.3%); an effect apparently conduced via oxidative DNA damage as revealed by the oxyDNA assay. The probable origin of this increased oxidative stress owes the removal of enough seminal plasma due to the unphysiological sperm extension, alongside a deleterious effect of high pressure on mitochondria during the sorting procedure. © 2016 Blackwell Verlag GmbH.

Morillo Rodriguez A.,Laboratory of Equine Reproduction and Equine Spermatology | Balao da Silva C.,Laboratory of Equine Reproduction and Equine Spermatology | Macias-Garcia B.,Laboratory of Equine Reproduction and Equine Spermatology | Gallardo Bolanos J.M.,University of Extremadura | And 4 more authors.
Reproduction in Domestic Animals | Year: 2012

Contents: A total of 42 ejaculates were used in the experiment; six ejaculates per stallion, obtained from seven Pure Spanish stallions (PRE), were split and frozen in freezing media with different concentrations and combinations of cryoprotectant (CPA): (i) Cáceres (skim milk based extender) containing 2.5% glycerol (2.5GL), (ii) Cáceres containing 1.5% glycerol and 1.5% dimethylformamide (1.5%GL-1.5%DMFA), (iii) Cáceres extender supplemented with 1.5% glycerol and 2.5% dimethylformamide (1.5%GL-2.5%DMFA) and (iv) Cáceres extender supplemented with 4% dimethylformamide (4%DMFA). After at least 4weeks of storage in liquid nitrogen (LN), straws were thawed and semen analysed by computer-assisted sperm analysis and flow cytometry (membrane lipid architecture (Merocyanine 540), integrity and sublethal damage (YoPro-1) and mitochondrial membrane potential (JC-1)). After thawing, better results were observed in samples frozen in 4%DMFA or in combinations of 1.5%GL-2.5%DMFA, in fact total motility increased by 16% in the 4%DMFA group compared to 2.5%GL (P<0.05). Also, there was an increment in the percentage of progressive motile sperm in the 1.5%GL-2.5%DMFA group (9.8% 2.5GL vs 19% in the 1.5%GL-2.5%DMFA group p<0.05); also, samples frozen in the 4%DMFA group had more intact (YoPro-1 negative) sperm post-thawing, 29.3% in 2.5%GL vs 36.7% in 4%DMFA group (p<0.05). Membrane lipid architecture was not affected by any of the cryoprotectants tested, while samples frozen in 4%DFMA had a lower percentage of mitochondria with lower membrane potential. It is concluded that DMFA improves the outcome of cryopreservation of stallion spermatozoa mainly reducing sublethal cryodamage. © 2012 Blackwell Verlag GmbH.

Discover hidden collaborations