Cryo letters.
Publisher:
Royal Veterinary College,. London, Eng. : CryoLetters
Frequency: Bimonthly
Country: England
Language: English
Start Year:1979 -
Identifiers
| ISSN: | 0143-2044 (Print) 0143-2044 (Linking) |
| NLM ID: | 9891832 |
| (OCoLC): | 06888267 |
| (DNLM): | SR0092119(s) |
| Coden: | CRLED9 |
| LCCN: | sc 82001467 |
| Classification: | W1 CR996 |
Cryoprotective effect of zinc and gold nanoparticles during cooling and freeze-thawing on Marwari stallion sperm parameters and reactive oxygen species production. Sperm cryopreservation is one of the most important procedures in the development of biotechnologies for assisted reproduction. Cryopreservation of stallion spermatozoa tends to cause plasma membrane damage due to the low ratio of cholesterol to phospholipids. Different substances and compounds can be added to semen extenders to improve sperm quality. Objective: To investigate the effect of supplementing semen extender with zinc nanoparticles (ZnONPs) and gold nanoparticles (AuNPs) on cooled and frozen-thawed spermatozoa of Marwari stallion. Methods: A total of 20 ejaculates from four Marwari ...
Freezing of equine semen is influenced by exposure time and concentration of the cryoprotectant glycerol. Glycerol is a cryoprotectant widely used in the freezing of mammalian semen, but no study has demonstrated its optimum concentration and the appropriate exposure time for equine species. Objective: To demonstrate that the exposure time (15, 30, 45, 60, 75 and 90 min) versus concentration (2, 3, 4 and 5%) of the cryoprotectant glycerol influences the freezing success of equine semen. Methods: The ejaculate of 12 stallions were frozen in different glycerol concentrations following different exposure times. The thawed sperm was evaluated for kinetic parameters using a Computer Assisted Semen Anal...
Effect of isolation protocols and cryoprotectants on freezing of stallion epididymal spermatozoa. The recovery of spermatozoa from the cauda epididymis may be the only option to obtain genetic material from elite stallions that had undergone castration or sudden death due to colic or severe injury. Objective: To evaluate two different protocols for retrieval of stallion epididymal spermatozoa and to evaluate different cryoprotectants on the freezability of the epididymal spermatozoa. Methods: Six epididymides from three stallions were collected immediately after routine castration under general anesthesia. In the first experiment, each epididymis (of two testes) of the same stallion were p...
Quality Improvement of Post-Thawed Stallion Epididymal Spermatozoa with Single Layer Centrifugation. Epididymal sperm cryopreservation represents the ultimate option to preserve spermatozoa of valuable stallions. Objective: The study aims to evalute whether single layer centrifugation (SLC) prior to cryopreservation or after post-thawing improves the quality of stallion epididymal sperm. Methods: Epididymal sperms of stallions were harvested (N=20). Sperm samples were subjected to treatments: conventional centrifugation, SLC prior to cryopreservation (SLC-PC) or SLC post-thaw (SLC+). All samples were cryopreserved, thawed and evaluated. SLC+ were thawed, single layer cenrifuged and resuspende...
In Vitro and In Vivo Efficiency of Extenders Added to Thawed Stallion Semen. Addition of extenders to thawed semen could improve fertility. Objective: To determine the efficiency of extenders to increase viability of thawed semen, measured by sperm parameters in vitro and pregnancy rates after artificial insemination (AI). Methods: Sperm motility and acrosin activity were measured during a thermoresistance test (TRT). Results: Progressive motility decreased (P<0.05) after 30 min in thawing semen treated with saline solution (SS) and only after 60 min with Tyrode's solution (TS) or freezing diluent (FD). The total motility decreased (P<0.05) after 60 min in thawed semen...
Optimization of the Protocol for Cryopreservation of Arabian Stallion Spermatozoa: Effects of Centrifugation, Semen Extenders and Cryoprotectants. Cryopreservation of Arabian stallion semen is important in order to improve the function and fertility of frozen/thawed semen in this breed. Objective: To investigate the effects of centrifugation, type of semen extenders, and type of cryoprotectants on the quality of frozen/thawed Arabian stallion spermatozoa. Methods: Semen samples collected from four adult Arabian stallions (one ejaculate per week for 10 consecutive weeks) were either processed directly without centrifugation (no centrifugation; NC) or subjected to centrifugation on the gel-free fraction. Centrifugation protocols were divid...
Freezing of Stallion Semen: in vitro and in vivo Evaluation of Sperm Motility and Acrosin Activity in Frozen-thawed Semen with Addition of Post-diluent Extenders. Post-diluents could potentially increase semen cryotolerance, but remain poorly explored in horses. The aim was to evaluate the efficiency of post-diluents on frozen-thawed semen viability of two stallions (S1-S2). The cryopreserved semen was thawed at 50°C for 40 seconds. Semen motility and acrosin activity (AA) were determined during the thermo-resistance test (TRT). Progressive motility of S2 semen decreased after 60 and 90 minutes of TRT (TRT60 and TRT90) on the control compared to both post-diluents. The total motility of both S1 and S2 decreased on TRT60 and TRT90 semen control versus b...
Evaluation of Fertilizing Ability of Frozen Equine Sperm Using a Bovine Zona Pellucida Binding Assay. Frozen equine semen has lower fertility compared to cooled semen. Due to the difficulty to obtain equine oocytes, a heterologous zona pellucida binding assay (ZBA) is an alternative method to predict the fertilizing capability of equine frozen sperm. The rate of capacitated and hyperactivated sperm according to their motility characteristics were analyzed with a Computer Assisted Sperm Analyzer. We believe this report describes for the first time the in vitro hyperactivation induction and the heterologous ZBA to predict the fertilizing ability of frozen equine sperm. Objective: This work aimed...
Quercetin in equine frozen semen. BACKGROUND: Supplementation of sperm diluents to reduce the damage caused by the freeze-thaw cycle is broadly used in equine semen cryopreservation. Objective: The present study aimed at determining the most appropriate quercetin supplementation in equine freezing extender. Methods: Quercetin at four different concentrations (0.25, 0.5, 0.75 or 1 mM) was added in the sperm freezing diluent before the freeze-thaw cycle. The spermatozoa population was analyzed by flow cytometry and a statistical analysis was conducted to detect significant differences between control and treated samples. R...
Variable Inter-assay Estimation of Sperm DNA Fragmentation In Stallions Classified as Good and Bad Semen Freezers. Semen cryopreservation causes DNA damage, thus requiring continuous monitoring. Objective: To compare two assays for sperm DNA fragmentation (SDF) from stallions with contrasting semen freezability. Methods: Thirteen stallions were classified as good semen freezers (GSF) or bad semen freezers (BSF). Ejaculates were cryopreserved with three diluents. Semen was subject to SDF evaluation using the sperm chromatin structure assay (SCSA) and Halomax after thawing (0 h) and after a 4 h thermoresistance test. Results: On semen of BSF, analysis by SCSA was similar between evaluations, but Halomax show...
Effect of Solid Medium During Cooled Storage on Stallion Sperm Parameters. Solid storage medium prevents cellular sedimentation, reduces metabolic demand via limiting movement, and avoids the modification of an extender composition in the sedimentary microenvironment. It has been proven to prolong spermatozoa viability in mammalians. Objective: This experiment aims to evaluate the effect of cool storage in solid phase extender on stallion sperms. Methods: Semen was collected from 10 Crioulo stallions (n=30) and submitted to treatments: control group (semen extender) and groups with gelatin addition in different concentrations (semen extender + 1%, 2% and 3%). Seminal...
Comparative analysis of cryoprotective agents influence on thermodynamic and kinetic parameters of equine and human hemoglobin molecules. Critical to the understanding the mechanism of destruction and protection during cryopreservation of biological objects is the knowledge of the conformational transitions of biopolymers experiencing low temperatures in the presence of cryoprotective agents. This information may be derived from the kinetic and thermodynamic parameters of macromolecular thermal denaturation kinetics under different environmental conditions. Objective: The study deals with the influence of cryoprotective agents (glycerol, 1.2-propanediol (1.2-PD), and dimethyl sulfoxide (DMSO)) on thermodynamic and kinetic parame...
Vitrification of equine oocytes with a polyvinyl alcohol after in vitro maturation with equine growth hormone and insulin-like growth factor-I. In vitro fertilization (IVF) procedures are limited by the inability to mature equine oocytes on in vitro methods. Objective: The aim of this study was to evaluate structural integrity of equine oocytes subjected to vitrification with a synthetic polymer (PVA). Methods: The effect of eGH and its relationship with IGF-I on in vitro maturation (IVM) were evaluated. Compact cumulus oocytes complexes (n=122) were cultured in TCM-199 with eGH, IGF-I or eGH+IGF-I for 30h at 38.5C in air with 5 % CO2. Oocytes were fixed after IVM or subjected to the vitrification protocol. Cryopreserved oocytes were ...
Caseinate protects stallion sperm during semen cooling and freezing. Extenders with a defined composition containing only components with clearly protective effects on sperm during storage would be an advantage. The aims of the present work were to assess whether caseinate, improves cooled and frozen equine semen quality. Semen from six stallions were suspended with four different cooling extenders C1) Kenney extender; C2) 0.6 % caseinate; C3) 2.7 % caseinate ; and C4) C1 + 2.1 % caseinate, and frozen extenders: F1) INRA 82 extender; F2) 1.35 % caseinate; and F3) 2.7 % caseinate. Although there was no significant difference between the motility rate among the c...
Seminal freezing in pure breed andalusian horse: difference in individual stallions and correlation between pre and post-freezing sperm parameters. The aim of this study was the optimization of the sperm freezing protocols for the Pure Breed Andalusian Horse (AH) stallions. The study was performed in 84 ejaculates from 14 stallions (6 ejaculates per stallion). We examined the effect of individual stallion, centrifugal force and centrifugation extender on post-thaw sperm quality. Neither centrifugal force nor centrifugal extender had any significant effect on post-centrifugation or post-thawing sperm quality. Stallion was the principal source of variation in our experiments, showing individual significant differences (p < 0.05) in all para...
Addition of ficoll and disaccharides to vitrification solutions improve in vitro viability of vitrified equine embryo. The aim of the present study was to evaluate the in vitro viability of equine embryos vitrified in three different solutions. Day 6 and 6.5 embryos were measured and morphologically evaluated. Only grade 1 or 2 morulae and early blastocysts were vitrified. Eighteen embryos were distributed in Group 1: 40 percent ethylene glycol in PBS, Group: 2 and 3: 40 percent ethylene glycol, 18 percent Ficoll, 0.3M sucrose or 0.3M trehalose in PBS, respectively. The vitrified embryos were loaded individually into 0.25 ml straws, which were cooled and immersed in liquid nitrogen. After warming at 20 degree ...
Cryopreservation of horse semen under laboratory and field conditions using a Stirling Cycle freezer. A Stirling Cycle freezer has been developed as an alternative to conventional liquid nitrogen controlled rate freezers. Horse semen samples were cooled in 0.25 ml straws and 15 ml bags in the Stirling Cycle freezer under laboratory conditions and as a portable device, powered from a car battery. For comparison, straws were frozen in a conventional liquid nitrogen controlled rate freezer. Upon thawing, motility and viability of samples frozen in the Stirling Cycle freezer were not significantly different when compared to samples frozen in the liquid nitrogen freezer. Unlike liquid nitrogen syst...
The influence of 1-10 kD fraction from brains of the hibernating ground squirrel and the Yakut horse on proliferation and protein synthesizing system of Ehrlich ascitic carcinoma cells. The experimental data presented in the work testify to the cytostatic activity of 1-10 kD polypeptide fractions from brains of the hibernating ground squirrel and the Yakut horse towards Ehrlich ascitic carcinoma (EAC) cells. The experiments on the investigation of the inhibiting influence of 1-10 kD fractions from tissues of the hibernating and cold-adapted animals on protein-synthesizing system of EAC cells allow us to conclude that the cytostatic effect of the fractions is effected at the genetic level in the tumor cells.