Post-thaw Sperm Research Articles

Effect of Different Dilution Methods and Ratios of Ram Semen on Sperm Parameters after Cryopreservation.

The dilution method and ratio were tested to assess their effects on the Hu ram semen after cryopreservation. Experiment I aimed to explore the effect of various dilution ratios (1:1, 1:2, 1:3, 1:4) of diluent I (Tris-based and egg yolk) under the condition of 1:1 dilution of diluent II (diluent I and glycerol) on the Hu ram semen preserved in liquid nitrogen regarding spermatozoa motility and kinetic parameters. Experiment II aimed to investigate the effect of various dilution ratios (1:1, 1:2, 1:3, 1:4) of diluent I under the condition of 1:2 dilution of diluent II to the Hu ram semen for cryopreservation on spermatozoa motility and kinetic parameters. The purpose of experiment III is to assess the effect of various dilution methods and ratios on the cryopreservation of Hu ram semen by detecting spermatozoa motility, kinetic parameters, plasma membrane integrity, acrosome integrity and reactive oxygen species (ROS) level. Experiment III includes four groups: one-step dilution method and two-step dilution method. The two-step dilution method includes two groups: 1:2, 1:1 and 1:3, 1:2, and the one-step dilution method includes two groups: 1:5 and 1:11. The results indicated that the post-thawed spermatozoa total motility (TM), progressive motility (PM) and average motion degree (MAD) were highest in the 1:2 group and significantly higher (p < 0.05) than those in the 1:1 and 1:4 groups under the condition of 1:1 dilution of diluent II. The post-thawed spermatozoa TM and PM of the 1:3 group were significantly higher (p < 0.05) than those of the other groups under the condition of 1:2 dilution of diluent II. The post-thawed spermatozoa TM, PM, plasma membrane integrity and acrosome integrity of the two-step group (1:3, 1:2) were the highest and significantly higher (p < 0.05) than those in the other groups. Additionally, the post-thawed spermatozoa ROS level of the two-step group (1:3, 1:2) was significantly lower (p < 0.05) than that in the one-step groups (1:5 and 1:11). Therefore, a two-step dilution (1:3, 1:2) was found to be the most suitable method and ratio for diluting the Hu ram semen after cryopreservation.

Evaluation of Different Thawing Protocols on Iberian Boar Sperm Preserved for 10 Years at Different Liquid Nitrogen Levels.

The conservation of genetic resources in pig breeds, notably the Iberian pig, is crucial for genetic improvement and sustainable production. Prolonged storage in liquid nitrogen (LN2) is recognized for preserving genetic diversity, but potential adverse effects on seminal quality remain debated. This study aims to assess the impact of ten years of storage at different LN2 levels and to optimize thawing protocols for Iberian pig sperm. Sperm samples from 53 boars were cryopreserved and stored at varying LN2 levels and, a decade later, the samples were thawed at 37 °C for 20 s or at 70 °C for 8 s. Sperm motility, membrane integrity, acrosome status, and DNA fragmentation were evaluated in year 0 and year 10. Overall, no significant differences were observed in post-thaw sperm quality between storage levels in year 0 or year 10. But thawing at 70 °C 8 s showed significant improvements, particularly in samples that were always stored in LN2, in all analyzed parameters except fragmentation, which was not affected by cryostorage. This study suggests that the long-term preservation of Iberian pig sperm does not affect quality over time, regardless of whether the samples were fully submerged in LN2. Furthermore, it is determined that thawing at 70 °C for 8 s maximizes post-thaw sperm quality, especially in those samples stored constantly submerged in LN2.

Effects of apigenin and trans-ferulic acid on microscopic and oxidative stress parameters in the semen of water buffalo bulls during cryopreservation

Cryopreservation involves exposing sperm to stressful conditions that affect cell viability. The high quality of the Azerbaijani water buffalo's by-products, such as buffalo milk, makes it a species of significant importance. Our focus is on protecting its genetic resources by preserving its sperm, as their numbers will decrease in the coming years and they are at risk of extinction. This study's goal was to ascertain how apigenin (A) and trans-ferulic acid (t-FA) affected the semen quality of Azari water buffalo bulls under cryopreservation. Pooled buffalo sperm (n = 35 ejaculations) were diluted in a Tris-based diluent also containing varying amounts of apigenin (0.2, 0.4, 0.6, and 0.8 mM) and trans-ferulic acid (2.5, 5, 10 and 20 mM). Following a freeze-thaw procedure, samples were assayed for total antioxidant capacity (TAC), catalase (CAT), superoxide dismutase (SOD), malondialdehyde (MDA), glutathione activity (GSH), glutathione peroxidase (GPx), progressive motility and total motility, motility properties, plasma membrane functionality, and viability. Sixty days after insemination, the rectal examination was performed on 38 buffaloes that had undergone sexual breeding to confirm pregnancy. The results of the study show that the addition of A-0.2, A-0.4, and t-FA-10 to buffalo semen increases the percentage of intact plasma membrane, motility, and sperm viability, as well as the levels of GSH, GPx, CAT. and TAC. In addition, there is a decrease in MDA and DNA damage after cryopreservation. Furthermore, the results show that 0.4 mM apigenin significantly increases conception rates compared to the control group. The base extender of Tris supplemented with A (0.4 and 0.2 mM) and t-FA (10 mM) improves the antioxidant indices of both frozen and thawed buffalo sperm, which in turn improves post-thawing sperm quality and in vivo fertility improves buffalo sperm.

Cryopreservation of sperm from the gudgeon, Microphysogobio rapidus (Cyprinidae): Effects of cryoprotectant, diluents, and dilution ratio

We investigated methods for cryopreserving sperm from the endangered gudgeon, Microphysogobio rapidus, by examining the effects of cryoprotective agent (CPA) concentration, diluent, and dilution ratio on post-thaw sperm quality. The quality of frozen sperm was evaluated in terms of motility and kinematic parameters, viability, DNA damage, and fertilization rate. We evaluated methanol, glycerol, dimethyl sulfoxide (DMSO), and ethylene glycol as CPAs. Sperm motility, velocity, and viability were significantly higher when methanol was used as the CPA (p < 0.05). The diluents tested were Ringer's solution, Kurokura's Extender, Common Carp Sperm Extender (CCSE), and buffered sperm motility-inhibiting saline solution (BSMIS); post-thaw motility was highest when Ringer's solution was used as the diluent. Next, various quantities of methanol were combined with Ringer's solution to identify the optimal dose of methanol. The dilution ratios tested ranged from 1:1 to 1:7. Cryopreserved sperm was thawed at 20 °C for 15 s. The use of 10% methanol with Ringer's solution at a dilution ratio of 1:5 resulted in the highest post-thaw sperm motility, viability, and velocity including VAP, VCL, and VSL. Post-thaw sperm showed significantly greater DNA damage than the control (fresh sperm) (p < 0.05). The fertilization rate was highest with fresh sperm (p < 0.05), followed by sperm frozen with 10% methanol + Ringer's solution. We recommend that the best way to preserve sperm in the studied species is to use a combination of Ringer's solution and 10% methanol at a 1:5 dilution ratio. Our findings will facilitate the artificial fertilization of M. rapidus.

Post-thaw sperm morphokinetics and mitochondrial genes profile of buck semen supplemented with selenium in two different forms

Background The quality characteristics of semen is a determinant factor for improving fertility of rabbit. Objectives The current investigation was done to evaluate post-thaw sperm morphokinetics and mitochondrial genes expression profile of buck semen supplemented with selenium in two different forms. Materials and methods Sexually mature bucks (n=16) that aged three months on average were used for collecting two ejaculates which were evaluated using computer assisted semen analysis (CASA) program. The semen samples of all experimental animals which recorded progressive motility greater than or equal to 70% were pooled for cryopreservation. The pooled semen was divided into three groups that were supplemented with selenium nanoparticles and selenium in normal form in addition to the control group. Morphological characteristics as well as CASA parameters were assessed after freezing for 1 week. Moreover, enzymatic activity assays were performed to measure the antioxidant capacity of cryopreserved buck semen. Transcriptional profile of mitochondrial activity and antioxidant defense regulating genes was conducted using quantitative real-time polymerase chain reaction (PCR). Results and conclusion The addition of selenium in normal and Nano forms has significantly (P ≤0.05) enhanced some of CASA parameters such as DCL (µm), DAP (µm), DSL (µm), VCL (µm/s), VAP (µm/s), Amplitude of lateral head (ALH) (µ), BCF (Hz), and VSL (µm/s) during prefreezing period compared with control group. Moreover, the data presented in the present study indicated a significant (P ≤0.05) improvement of post-thaw total and progressive sperm motility in the two groups supplemented with normal and Nano compared with control group. The post-thaw level of total antioxidant capacity (TAC) and percentage of live sperm were higher in the two groups supplemented with selenium and Nano selenium than the control group. The expression profile of candidate genes regulating mitochondrial activity (ATP Synthase F1 Subunit Alpha (ATP5A1), NADH dehydrogenase subunit1 (ND1), NADH dehydrogenase subunit2 (ND2), and Carnitine palmitoyltransferase (CPT2)) was increased significantly (P ≤0.05) in semen supplemented with selenium in normal and Nano forms compared with the control group. In conclusion, the data of this investigation demonstrated enhancement of CASA parameters during pre-freezing post thaw total and progressive sperm motility in the two groups supplemented with normal and nano selenium. The proportion of sperm viability and the level of total antioxidant capacity were enhanced in the two groups supplemented with selenium which was coupled with up-regulation of mitochondrial transcripts. It seems the both two forms shared the same mechanism on improving post-thaw physical and molecular qualities of rabbit sperm.

Apigenin supplementation substantially improves rooster sperm freezability and post-thaw function

This pioneering research investigated apigenin potential to augment rooster sperm cryosurvival in an extender model. Apigenin is a natural antioxidant flavonoid showing promise for improved post-thaw sperm function. However, its effects on avian semen cryopreservation remain unexplored. This first study supplemented rooster sperm Lake extender with 0, 50, 100, 200, 400 μmol/L apigenin to determine the optimal concentrations for post-thaw quality. Supplementation with 100 μmol/L apigenin resulted in significant enhancements in total motility (from 41.5% up to 71.5%), progressive motility (18.1% to 29.1%) (p < 0.05), membrane integrity (40% to 68%), mitochondrial function (p < 0.001), viability (37% to 62%) and total antioxidant capacity (p < 0.001) compared to the control. It also substantially reduced percentages of abnormal morphology, reactive oxygen species and apoptosis (p < 0.001). Although 200 μmol/L apigenin significantly enhanced some attributes, effects were markedly lower than 100 μmol/L. Higher doses did not improve cryoprotective parameters. This indicates 100 μmol/L as the optimal apigenin concentration. This represents the first report of apigenin protecting rooster sperm from cryodamage. The natural antioxidant improved post-thaw sperm quality, likely by suppressing oxidative stress and apoptosis. Apigenin shows promise for enhancing rooster sperm cryosurvival.

Evaluation of the effects of glucose concentration in extender and sperm concentration in straw for cryopreservation of Atlantic sturgeon (Acipenser oxyrinchus) semen

The Atlantic sturgeon (Acipenser oxyrinchus) faces unique conservation challenges due to its extended maturation period and irregular spawning patterns, which restrict its reproductive capacity. Therefore, in order to overcome these difficulties we have made a first attempt to develop effective cryopreservation procedure for Atlantic sturgeon through evaluation of the effects of the glucose concentration in extender and final sperm concentration in straw on sperm motility parameters. A remarkably high (81 ± 8%) postthaw sperm motility was obtained. The other sperm velocity and trajectory parameters were differentially affected both by concentrations of glucose or sperm and cryopreservation process. Our results undoubtedly show that the post-thaw sperm motility of Atlantic sturgeon is highly influenced by the final glucose and sperm concentration. The recommended cryopreservation procedure includes 0.05 M glucose and 7.5% methanol at 1.0×109 spermatozoa ml−1. We have confirmed that our elaborated protocol can be used for cryopreservation of Atlantic sturgeon semen which can be subsequently used for long-term conservation of this endangered species, offering a valuable tool in efforts to safeguard its genetic diversity and contribute to its survival.

Cryopreservation of human semen by inherently-controlled icing probability: Or how the surface profile of superhydrophobic carbon soot coatings and the sperm volume affect the outcome of slow freezing?

The restoration of initial functionality of human spermatozoa subjected to cryopreservation is challenging, because the deleterious intracellular icing and the occurrence of osmotic shocks due to prolonged exposure to increased concentrations of intracellular solutes are oppositely dependent on the cooling rate. This longstanding problem could be overcome if using superhydrophobic soot coatings delaying the heat transfer rate, reducing the ice formation probability and triggering balanced and timely dehydration of the cells, but the effect of their surface profile and sperm volume on the success rate of slow freezing is unclear. Here, we show for the first time that the two-factor freezing injury is entirely avoidable by tailoring the solid-to-gas voids (pores) fraction in the soot, leading to increased nucleation free energy barrier, presumable incipiency of ice crystals with controllable shape and size and hence, fully (100 %) recovered post-thaw sperm motility. It is demonstrated that the reason for such a unique scientific result is the selection of soot coatings with appropriate morphochemical features, hypothetically (not directly proven yet) inducing equilibrium among the solution composition and ice crystals formation, retarding the undesirable compression of liquid-filled “slush ice” channels surrounding the cytoplasm and impeding the ice recrystallization. The novel insights introduced in this article open endless horizon for customizing and revolutionizing the technical protocols in cryobiology.

Camellia oil with its rich in fatty acids enhances post-thawed boar sperm quality

BackgroundBoar sperm are highly susceptible to specific conditions during cryopreservation, leading to a significant decrease in their fertilizing potential due to damage to their membranes. Camellia oil, known for its fatty acids with antioxidant and biological properties, has not been previously explored for the cryopreservation of boar semen. This study aimed to examine the effects of camellia oil on post-thawed boar sperm quality. Boar semen ejaculates (n = 9) were collected and divided into six equal aliquots based on camellia oil concentrations (0, 0.5, 1, 1.5, 2 and 2.5% v/v) in the freezing extender. Semen samples were processed and cryopreserved using the liquid nitrogen vapor method. Thereafter, frozen semen samples were thawed at 50 °C for 12 s and evaluated for sperm morphology by scanning electron microscope, sperm motility using a computer-assisted sperm analyzer, sperm viability, acrosome integrity, mitochondrial function, MDA level and total antioxidant capacity.ResultsThe results demonstrated that the supplementation of 1.5% (v/v) camellia oil showed superior post-thaw sperm qualities such as improved sperm morphology, motility, acrosome integrity and mitochondrial function by 14.3%, 14.3% and 11.7%, respectively, when compared to the control group. Camellia oil at a concentration of 1.5% (v/v) showed the lowest level of MDA (18.3 ± 2.1 µmol/L) compared to the other groups.ConclusionsIn conclusion, adding 1.5% (v/v) camellia oil in the freezing extender reduced the oxidative damage associated with cryopreservation and resulted in a higher post-thawed sperm quality.

Factors affecting the analysis and interpretation of sperm quality in frozen/thawed stallion semen

In the current study, we examined: 1) the agreement (bias) between fluorescence-based methods (NucleoCounter-SP100 [NC] vs. flow cytometry [FC]) for determining the viability (VIAB) of frozen/thawed stallion sperm; 2) the agreement between post-thaw sperm total motility (TMOT) and VIAB; 3) whether a difference between TMOT and VIAB [VIAB – TMOT] in frozen/thawed stallion sperm could be explained by the level of lipid peroxidation in viable sperm (VLPP); 4) the repeatability of post-thaw analysis of sperm quality; and 5) the effect of final post-thaw semen dilution (10, 30, or 50 x 106 sperm/mL) on sperm motion characteristics. Post-thaw VIAB was similar between NC and FC (P > 0.05), and the agreement between these two methods was high (bias: 1 to −3). The agreement between post-thaw TMOT and VIAB decreased as the pre-freeze percentages of morphologically normal sperm and DNA quality decreased: bias – 4 to – 25. The bias between [VIAB – TMOT] and VLPP ranged from – 5 to 7. Differences in post-thaw sperm quality (TMOT, PMOT, VIAB, and sperm concentration) were not observed when analyzing one or three straws per ejaculate (P > 0.05). There was no effect of post-thaw sperm concentration (i.e., 10 vs. 30 vs. 50 x 106 sperm/mL) on sperm motion characteristics (P > 0.05). This study reports factors other than post-thaw sperm motility that warrant further consideration when analyzing frozen/thawed stallion sperm.

Optimizing aquaculture-scale common carp artificial reproduction: a novel approach to sperm cryopreservation using large-volume containers and elevated thawing temperatures

IntroductionThe successful cryopreservation of common carp sperm is crucial for its application in aquaculture and selective breeding programs. This study investigates the efficacy of cryopreserving sperm in large containers (5 mL) with a low dilution rate (1:1) in three different cryoprotective media and thawing in different conditions.MethodsThe developed method utilizes a low-ionic (hypotonic) cryoprotective medium, freezing with a controlled cooling rate, and high-temperature sperm thawing (60°C). The investigation employs a detailed spermatozoon motility assessment.ResultsPost-thaw motility of 32.3% ± 14% and initial curvilinear velocity of 89 ± 20 μm/s across 30 males were observed. Principal component analysis of sperm kinematic characteristics revealed distinct populations of sperm cells exhibiting varying responses to cryopreservation. The developed method achieved successful fertilization comparable to that of the non-frozen control group using sperm from a single cryotube (2.5 mL, approximately 50 * 109 spermatozoa) to fertilize 200 g of eggs (1:120,000 egg:spz).DiscussionThis novel approach demonstrates an effective cryopreservation protocol for common carp sperm in large-volume cryo-containers in combination with low-ionic cryomedia and high thawing temperature, providing methods well-suited for fisheries practices and selective breeding programs. Future studies of the biological properties of different sperm subpopulations in post-thaw sperm samples can contribute to a deeper understanding of sperm biology, improve cryopreservation techniques, and enhance the success rates of assisted reproductive technologies.

Association of the polymorphism of the Pon-1 locus with the concentration of Paraoxonase-1 and post-thaw sperm viability in pig

The objective of the present work was to correlate the expression of the PON-1 locus polymorphism, the concentration of the enzyme paraoxonase 1 in seminal plasma and the effect on post-thawing sperm viability in the pig. Nine ejaculates from 3 boars were used, to obtain seminal plasma; part of the ejaculates was centrifuged at 800 g/10 min; the material obtained was stored at -20°C until use. To freeze the semen, the samples were diluted 1:1 in commercial diluent (Magapor®) at 37°C and the temperature was gradually lowered to 16°C. They were transported to the laboratory protected from light, and kept at the same temperature in the laboratory for 24 h. After this, they were frozen using the glycerolation technique and a portion was cryopreserved by adding 20% of seminal plasma to the conservation medium and another portion was made without seminal plasma. The concentration of PON-1 was determined by an enzyme-linked immunosorbent assay (ELISA). The functional status of the plasma membrane was evaluated by chlortetracycline staining. The amplification of a fragment of the PON-1 gene was carried out by PCR and the identification of allelic variability by the analysis of Restriction Fragment Length Polymorphism (RFLP), with the enzymes HinfI and FokI, from a DNA sample of each individual. The results were analyzed by analysis of variance (ANOVA) and Spearman correlation, with the use of statistical software (Statistica V10 for Windows). In electrophoresis of enzymatic digestion with the enzyme HinfI All the expected fragments were obtained, with the FokI enzyme a mutation was observed in one individual. No correlation was observed (R=-0.1, P&gt;0.05) between the concentration of the paraoxonase-1 enzyme in seminal plasma and the observed mutations. As well as the concentration of the enzyme paraoxonase-1 in the ejaculates was 1.8 to 2.7 ng/mL and this had no statistically significant difference in the seminal plasma of the ejaculates analyzed (P&gt;0.05). As well as with sperm viability in thawed semen (P&gt;0.05).

Effects of different ages on frozen semen quality and in vitro fertilization efficiency in Wannan black pigs.

According to previous studies, the quality and fertilization rate of fresh sperm from boars of different ages were significantly different. However, the difference of freeze-thaw sperm quality and fertility in boars of different ages is unclear. In this study, boars of a Chinese native breed were assigned into two groups. Each group consisted of five boars aged aged either 2-3 years (young boars = YB) or 5-6 years (aging boars = AB) A total of 60 ejaculates for each group were collected and cryopreserved. Semen quality and in vitro fertility of post-thaw sperm was evaluated. The results showed that the concentration and motility of fresh sperm collected from AB were similar to YB, but their semen volume was higher than that in YB (p < 0.05). Frozen-thawed sperm of AB had lower viability than YB, and higher abnormal rate and reactive oxygen species (ROS) levels of YB (p < 0.05). There was no effect of the age on post-thaw sperm motility and time survival. Functional assessments indicated that increasing age markedly compromises the integrity of the sperm plasma membrane and acrosome, as well as mitochondrial functionality post-thaw, albeit without affecting DNA integrity. Furthermore, increasing age of boars reduces the ability of sperm to bind to the oocyte zona pellucida after thawing, delaying the time of the first embryo cleavage after fertilization. Finally, the early developmental efficiency of in vitro fertilized embryos progressing from 4-cell to blastocyst derived from post-thaw sperm in AB significantly decreased compared to those from YB (p < 0.05). Taken together, these results suggest that increasing age in boars impairs the quality and in vitro fertility of frozen thawed sperm.

Quality and kinematic characteristics of Bali bulls frozen semen with purified green tea extract epigallocatechin-3-gallate antioxidant addition in diluent.

The preservation of semen quality and kinematic characteristics during cryopreservation is crucial for the reproductive success and genetic management of livestock, particularly in Bali bulls. This study aimed to investigate the effect of adding purified green tea extract antioxidant Epigallocatechin-3-gallate (EGCG) in tris egg yolk diluent on the quality and kinematic characteristics of frozen semen from Bali bulls. Fresh and frozen semen samples were obtained from Bali bull and divided into four different treatment groups. P0 contained semen samples + diluent, while P1 to P3 consisted of semen samples + diluent supplemented with EGCG levels of 0.1, 0.15, and 0.2 mg/100 ml, respectively. Data were analyzed using One-way ANOVA and followed by Duncan's test if significant differences were found (p<0.05). Parameters observed included the assessment of fresh semen quality, kinematic analysis, post-thawing sperm viability, and abnormality. The results indicated that the assessment of fresh semen quality showed macroscopic and microscopic semen quality according to SNI 4869-1:2021. Kinematic analysis revealed significant differences in DSL and STR parameters between P0 and P3 (p<0.05). EGCG supplementation also caused significant differences in motility between P0 and P3 (p<0.05). Viability and spermatozoa abnormality with EGCG supplementation did not show significant differences (p>0.05). The best results for motility, kinematics, and sperm morphology variables were found in P1 as it did not exhibit a decrease in motility, kinematics, and sperm morphology. Viability did not show significant differences between P1, P2, and P3, but the best results were found in P2 as it did not exhibit a decrease in viability with mean and standard deviation (66.84 ± 7.88). Abnormality variables also did not show significant differences between P1, P2, and P3, but the best results were found in P2 as it did not exhibit a decrease in abnormality with mean and standard deviation (23.80 ± 7.36).

The antioxidant effects of butylated hydroxytoluene on cryopreserved goat sperm from a proteomic perspective.

At present, there are few reports about the proteomics changes provoked by butylated hydroxytoluene (BHT) supplementation on cryopreserved semen in mammals. Thus, we aimed to evaluate the effects of different concentrations of BHT on goat sperm and to investigate the proteomics changes of adding BHT to cryopreserved goat (Capra hircus) sperm. Firstly, semen samples were collected from four goats, and frozen in the basic extenders containing different concentrations of BHT (0.5 mM, 1.0 mM, 2.0mM) and a control without BHT, respectively. After thawing, the protective effects of dose-dependent replenished BHT to the freezing medium on post-thaw sperm motility, integrities of plasma membrane and acrosome, reactive oxygen species levels were confirmed, with 0.5 mM BHT being the best (B group) as compared to the control (without BHT, C group). Afterwards, TMT-based quantitative proteomic technique was performed to profile proteome of the goat sperm between C group and B group. Parallel reaction monitoring was used to confirm reliability of the data. Overall, 2,476 proteins were identified and quantified via this approach. Comparing the C and B groups directly (C vs. B), there were 17 differentially abundant proteins (DAPs) po-tentially associated with sperm characteristics and functions were identified, wherein three were upregulated and 14 were downregulated, respectively. GO annotation analysis demonstrated the potential involvement of the identified DAPs in metabolic process, multi-organism process, reproduction, reproductive process, and cellular process. KEGG enrichment analysis further indicated their potential roles in renin-angiotensin system and glutathione metabolism pathways. Together, this novel study clearly shows that BHT can effectively improve quality parameters and fertility potential of post-thawed goat sperm at the optimal concentration, and its cryoprotection may be realized through regulation of sperm metabolism and antioxidative capability from the perspective of sperm proteomic modification.

Assessing the efficacy of different semen extenders on post-thaw quality of Bangladeshi buffalo sperm under a manual cryopreservation protocol

Cryopreservation has been used extensively for cattle in Bangladesh, albeit no study was conducted on the cryopreservation of buffalo sperm in Bangladesh. This study aimed to evaluate the suitability of different semen extenders for improving the post-thaw quality of Bangladeshi buffalo sperm under a manual cryopreservation protocol. The manual cryopreservation protocol was compared and optimized with a commercial biofreezer protocol. Then, the efficacy of different diluters was evaluated using the optimized manual cryopreservation protocol. Meanwhile, the post-thaw sperm quality in terms of motility and morphology was evaluated by CASA during the optimization process. During manual cryopreservation, the first cooling from 37 °C to 5 °C was done in a BLRI-developed equilibration chamber and the second cooling from 5 °C to -120 °C in a Styrofoam box using liquid nitrogen vapor from different distances (0.5, 1.5, 1.6, 2 and 3 inches). Simultaneously, another batch of sperm was cryopreserved using a programmable freezer. The highest number of motile sperms (62.67±1.12; P&lt;0.01) and progressive motility (38.97±1.10; P&lt; 0.001) was observed at 1.6 inches above liquid nitrogen, which are similar to the results obtained from automated biofreezer protocol (65.94±4.65 and 45.54 ± 3.64, respectively). To evaluate the semen extenders’ efficacy, one locally developed Tris-fructose-egg yolk-based diluter and two commercial diluters (Andromed, Triladyl) were used in the freezing of buffalo sperm. The highest recovery and conception rates were observed in sperm diluted with TFE (82.4% and 80%, respectively). Therefore, it is clear that this manual cryopreservation protocol and the TFE diluter could be a suitable and inexpensive alternative for Bangladeshi buffalo sperm considering post-thaw sperm quality and fertility.

Studies on Fresh and Cryopreserved Seminal Attributes in Beetal Bucks Outside their Breeding Tract

The objectives of the present research were to assess fresh and cryopreserved. seminal characteristics of breeding Beetal buck semen outside of its breeding tract. Semen was collected twice in a week from twelve Beetal bucks for 6 weeks. The mean value of ejaculate volume(ml), mass motility(o-5 scale), progressive motility(%), sperm viability (%), intact acrosome(%), sperm abnormality(%) and plasma membrane integrity(%) were ranged from 0.73 ± 0.08 ml to 1.17 ± 0.27 ml; 4.17+ to 4.67+, 80.83 ± 1.54 to 87.50 ± 2.14; 83.83 ± 0.95 to 90.33 ± 0.80; 87.00 ± 0.86 to 94.67 ± 0.33; 6.83 ± 0.31 to 10.33 ± 0.67 and 59.33 ± 1.52 to 66.67 ± 1.17, respectively. The mean value of post thaw sperm motility, post thaw sperm viability, post thaw acrosome integrity, post thaw sperm abnormalities and post thaw plasma membrane integrity were ranged from 52.50± 1.12 to 66.67 ± 1.67; 60.00 ± 1.24 to 69.67 ± 1.05; 66.00 ± 0.77 to 78.83 ± 2.15; 9.00 ± 0.45 to 12.83 ± 0.60 and 41.50 ± 1.18 to 53.50 ± 1.23, respectively. It was determined that, even outside of the breeding tract, the foundational characteristics of Beetal bucks are within the range defined for other Indian breeds of goat.

Resveratrol Improves the Frozen-Thawed Ram Sperm Quality.

Cryopreservation generates a substantial quantity of ROS in semen, leading to a decline in sperm quality and fertilization capacity. The objective of this study was to investigate the effects of resveratrol and its optimal concentration on ram sperm quality after cryopreservation. Ram semen was diluted with a freezing medium containing different concentrations of resveratrol (0, 25, 50, 75, and 100 μM). After thawing, various sperm parameters such as total motility, progressive motility, acrosome integrity, plasma membrane integrity, mitochondrial membrane potential, glutathione (GSH) content, glutathione synthase (GPx) activity, superoxide dismutase (SOD) activity, catalase (CAT) activity, lipid peroxidation (LPO) content, malondialdehyde (MDA) content, ROS level, SIRT1 level, DNA oxidative damage, and AMPK phosphorylation level were assessed. In addition, post-thaw sperm apoptosis was evaluated. Comparatively, the addition of resveratrol up to 75 μM significantly improved the sperm motility and sperm parameters of cryopreserved ram sperm. Specifically, 50 μM resveratrol demonstrated a notable enhancement in acrosome and plasma membrane integrity, antioxidant capacity, mitochondrial membrane potential, adenosine triphosphate (ATP) content, SIRT1 level, and AMPK phosphorylation levels compared to the control group (p < 0.05). It also significantly (p < 0.05) reduced the oxidative damage to sperm DNA. However, detrimental effects of resveratrol were observed at a concentration of 100 μM resveratrol. In conclusion, the addition of 50 μM resveratrol to the cryopreservation solution is optimal for enhancing the quality of cryopreserved ram sperm.

Comparison of different freezing techniques, extenders, and cryoprotectants on quality and fertility of cryopreserved Salmo trutta f. fario sperm

There is still a lack of standardized methodology in the cryopreservation of Salmo trutta f. fario sperm. Thus, the present study was designed to compare current freezing protocols to improve and as well as to examine the post-thaw quality and fertilizing ability of cryopreserved sperm in Salmo trutta f. fario. Sperm samples were diluted at a 1:10 ratio in one of three extenders (Alsever’s solution, glucose-based, and ionic-based) containing four types of cryoprotectant (DMSO, DMA, MeOH, glycerol) at 10% concentration and frozen in 0.1 mL pellets on surface of the dry ice (solid carbon dioxide, 79°C) or in 0.25 mL straws 2 cm above of the liquid nitrogen (LN2) surface at a rate of ~30°C for 10 min.1 before storage in a mL cryotank (-196°C). The frozen sperm cells in straws and pellets were thawed in a water bath at 25°C for 30 s and at 20°C for 6 s respectively. Fertilization was carried out using a ratio of 5x105 sperm/egg in both freezing methods. The glucose-based solution including glycerol produced the highest post-thaw progressive motility (62.5 ± 1.24%), motility duration (57.2 ± 0.46 s), and viability (56.4 ± 1.57%) (p &lt; 005) in the straw method. In breeding trials, similarly, sperm frozen-thawed with the glucose-based solution including glycerol produced the highest fertilization (54.2 ± 0.36%) and hatching (30.6 ± 0.28%) in the straw method. Fresh sperm used as control produced 82.6 ± 0.45% and 78.4 ± 1.27% fertilization and hatching respectively. It was concluded that sperm frozen in straws produced higher post-thaw sperm motility and fertility of eggs than those frozen in pellets. Also, the results suggest using of glycerol-supplemented glucose solution because of producing better results in both freezing techniques.

Differential metabolites screening in yak (Bos grunniens) seminal plasma after cryopreservation and the evaluation of the effect of galactose on post-thaw sperm motility

Sperm survival and activity depend on the provision of energy and nutrients from seminal plasma (SP). This study aimed to investigate the variations of metabolites within SP before and after freezing and subsequently explore the potential regulatory mechanisms affecting yak sperm cryodamage due to changes in metabolites in the SP. Untargeted metabolomics analysis was performed to screen for differential metabolites, followed by KEGG analysis to identify enriched signaling pathways. The combinatorial analysis of metabolomics and sperm proteomics revealed the influence of key SP metabolites on sperm proteins. Subsequently, the relevant differentially expressed proteins were verified by Western blot analysis. Finally, the mechanism underlying the positive effect of galactose on sperm motility was determined by assessing the change in ATP content in sperm before and after freezing and thawing. The data showed that a total of 425 and 269 metabolites were identified in the positive and negative ion modes, respectively. Freezing and thawing resulted in the up-regulation of 70 metabolites and the down-regulation of 29 metabolites in SP. The primary impact of freezing and thawing was observed in carbohydrate metabolism, including pyruvate metabolism, pentose phosphate pathway, galactose metabolism, the TCA cycle, and butanoate metabolism. In the combined analysis and Western blot results, a significant positive correlation was observed between galactose and Aldo-keto reductase family 1 member B1 (AKR1B1) (P < 0.05), which has the ability to convert galactose into galactol. Furthermore, the addition of galactose to thawed semen improved sperm motility by increasing AKR1B1 protein in sperm and was associated with the content of ATP. These data identify differential metabolites between fresh and frozen-thawed SP and suggest that galactose is a valuable additive for cryopreserved sperm, providing a theoretical basis for further exploration of the refrigerant formula for yak sperm cryopreservation.