Search Results (97)

Waterfowl semen cryopreservation technology is a key link in genetic resource conservation and artificial breeding, but poultry spermatozoa, due to their unique morphology and biochemical properties, are prone to oxidative stress during freezing, resulting in a significant decrease in vitality. In this study, we first used four different freezing procedures (P1–P4) to freeze duck semen and compared their effects on duck sperm quality. Then, the changes in antioxidant indexes in semen were monitored. The results showed that program P4 (initial 7 °C/min slow descent to −35 °C, followed by 60 °C/min rapid descent to −140 °C) was significantly better than the other programs (p < 0.05), and its post-freezing sperm vitality reached 71.41%, and the sperm motility was 51.73%. In the P1 and P3 groups, the sperm vitality was 65.56% and 53.41%, and the sperm motility was 46.99% and 31.76%, respectively. In terms of antioxidant indexes, compared with the fresh semen group (CK), the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-px) in the P2 group were significantly decreased (p < 0.05), while the activities of SOD and CAT in the P4 group showed no significant changes (p > 0.05) except that the activity of GSH-px was significantly decreased (p < 0.05). And the CAT and GSH-px activities in the P4 group were significantly higher than those in the P2 group (p < 0.05). The content of malondialdehyde (MDA) in the P2 group was significantly higher than that in the fresh semen group (p < 0.05), and there was no significant difference between the P2 group and the P4 group (p > 0.05). The total antioxidant capacity (T-AOC) content of the P2 and P4 groups was significantly lower than that of the fresh semen group (p < 0.05). The staged cooling strategy of P4 was effective in reducing the exposure time to the hypertonic environment by balancing intracellular dehydration and ice crystal inhibition, shortening the reactive oxygen species accumulation and alleviating oxidative stress injury. On the contrary, the multi-stage slow-down strategy of P2 exacerbated mitochondrial dysfunction and the oxidative stress cascade response due to prolonged cryogenic exposure time. The present study confirmed that the freezing procedure directly affects duck sperm quality by modulating the oxidative stress pathway and provides a theoretical basis for the standardization of duck semen cryopreservation technology. Full article

Liquid storage is an important tool used to prolong fresh semen shelf-life while protecting spermatozoa from damage, conserving their overall functionality, and ensuring better fertility than frozen semen from sheep. The increased production of reactive oxygen species (ROS) during sperm storage leads to a decline in sperm quality, particularly with regard to sperm nuclear DNA damage and mitochondrial membrane potential (MMP). This study evaluated the effect of storing Sarda ram semen at 15 °C for 7 h on its redox status, motility, morphology, acrosome integrity, ATP content, mitochondrial potential membrane, and in vivo fertility after artificial insemination. Two different extenders were compared: a lab-made skimmed milk (SM)-based extender and a commercial extender (OviXcell^®, IMV-Technologies, France). Lower ROS levels in the SM (p < 0.001) indicated that its oxidative status was better maintained compared to the commercial extender (CE). Antioxidant defenses (total antioxidant capacity, TEAC; superoxide dismutase, SOD; total thiols) were higher in the SM (p < 0.01) than in the CE. SM also had higher MMP (p < 0.05), acrosome integrity (p < 0.05), ATP content (p < 0.01), and in vivo fertilizing capacity (p < 0.05) compared to the CE, which indicated higher semen quality. In conclusion, the SM extender, while maintaining a better oxidative/antioxidant balance, ensured higher semen quality after 7 h of storage at 15 °C in vitro compared to the CE. Full article

Subfertile boars often go undetected until they cause significant reproductive losses. Current semen quality assessments are limited in their ability to predict fertility, highlighting the need for complementary biomarkers. This study explored whether semen freezability could serve as an indirect indicator of boar fertility. Eighteen boars were classified based on historical fertility records and semen freezability, assessed by post-thaw quality. Fresh and post-thaw semen samples were analyzed using the CASA system and fluorescence microscopy. High-fertility boars showed significantly better motility and functional sperm parameters in fresh semen compared to low-fertility boars. However, these differences were mostly lost after cryopreservation. Conversely, boars with good freezability had consistently better post-thaw semen quality, though this did not correlate directly with higher fertility outcomes. Notably, a combined analysis revealed that boars with both high fertility and poor freezability had the lowest post-thaw semen quality. This suggests that cryopreservation may expose hidden sperm defects not detectable in fresh semen. Total motility was the only parameter associated with both fertility and freezability. In conclusion, while freezability alone may not directly predict fertility, it may help identify low-performing males. The combined assessment of fresh semen motility and freezability could support more effective boar selection strategies. Full article

The corpus luteum (CL) is a transient gland that can directly influence follicular dynamics and oocyte quality. The objective of this study was to evaluate the influence of the absence or presence of a small (≤3 mm), medium (4–8 mm), or large (>8 mm) CL in slaughterhouse ovaries on in vitro embryo production. Cumulus–oocyte complexes (COCs) were collected from each group of ovaries and matured in TCM-199 medium, plus hormones and fetal bovine serum. Fertilization was performed with fresh semen from a Katahdin ram of known fertility. Embryo development was carried out in commercial sequential media for 72 and 96 h, until the blastocyst stage. The number of follicles (2–6 mm in diameter) and COCs were influenced by the presence of CL, which was higher (p < 0.05) in the Large CL group (5.51 ± 0.33 and 3.62 ± 0.27) compared to the Without CL group (4.54 ± 0.19 and 2.62 ± 0.14, respectively), with no difference between the CL sizes. Likewise, the diameter and area of the COCs were higher in the Small CL group of ovaries compared to the Without CL group. In the Large CL group of ovaries, 9% more morulae (p < 0.05) were obtained compared to the Without CL group; in the Medium CL group, 13% more blastocysts were obtained compared to the Without CL group. However, in the hatching capacity and diameter of blastocysts, no statistical difference was evident (p > 0.05). In conclusion, the presence and size of the CL in the ovaries of slaughtered sheep influence the productive efficiency of embryos in vitro under the conditions in which the present study was carried out. Full article

The cryopreservation of rabbit semen is a valuable strategy for genetic resource preservation and efficient artificial insemination, but outcomes remain inconsistent, partly due to variations in sperm concentration per dose. This study aimed to evaluate the in vivo effects of different sperm concentrations (15, 25, 35, 55, and 75 million per straw) on fertility, prolificacy, and offspring growth in nulliparous and multiparous does. A total of 384 rabbit females were inseminated using frozen–thawed semen, and their reproductive performance was compared with fresh semen. Fertility and kindling rates varied with sperm concentration and parity: nulliparous does showed the highest fertility at 15 million sperm/straw (84.4%), while multiparous does reached peak values at 25–55 million/straw (78.1–81.3%). Litter size and live-born kits were consistently higher in multiparous than in nulliparous does. Offspring body weight at 19 and 60 days was influenced by both sperm concentration and maternal parity, with better growth generally observed in multiparous groups. Weaning success remained high across all groups. Our results indicate that sperm concentrations ranging from 15 to 35 × 10⁶/straw are the most suitable for cryopreservation, as they maintain high fertility, prolificacy, and offspring growth, comparable to fresh semen. These results confirm that optimizing sperm concentration during cryopreservation improves reproductive efficiency and that tailoring insemination strategies to the physiological status of the female enhances outcomes. The results provide useful recommendations for improving cryopreservation techniques in rabbit breeding programs. Full article

Artificial insemination (AI) is a key breeding technique in the swine industry; however, the lack of reliable biomarkers for semen quality limits its effectiveness. Seminal plasma (SP) contains extracellular vesicles (EVs) that present a promising, non-invasive biomarker for semen quality. This study explores the biochemical profiles of boar SP to assess semen quality through near-infrared spectroscopy (NIRS) and proteomics of SP-EVs. Fresh semen from mature Duroc boars was evaluated based on sperm motility, classifying samples as Passed (≥70%) or Failed (<70%). NIRS analysis identified distinct variations in water structures at specific wavelengths (C1, C5, C12 nm), achieving high accuracy (92.2%), sensitivity (94.2%), and specificity (90.3%) through PCA-LDA. Proteomic analysis of SP-EVs revealed 218 proteins in Passed and 238 in Failed samples. Nexin-1 and seminal plasma protein pB1 were upregulated in Passed samples, while LGALS3BP was downregulated. The functional analysis highlighted pathways associated with single fertilization, filament organization, and glutathione metabolism in Passed samples. Integrating NIRS with SP-EV proteomics provides a robust approach to non-invasive assessment of semen quality. These findings suggest that SP-EVs could serve as effective biosensors for rapid semen quality assessment, enabling better boar semen selection and enhancing AI practices in swine breeding. Full article

The significant decline in amphibians worldwide is demanding the development of reliable techniques to save species and their genetic diversity. Considerable efforts are currently in progress to develop assisted reproductive technologies (ARTs), focusing mainly on sperm cryopreservation and in vitro fertilization (IVF). In Xenopus, a simple and efficient transgenesis method based on the intracytoplasmic injection (ICSI) of cryoconserved sperm was developed several decades ago, allowing for quick generation of large numbers of transgenic animals, for biological research. Such a methodology could be critical for the recovery of species and their genetic diversity, contributing to amphibian conservation. However, this approach raised the question of whether the sperm preservation method used with ICSI is compatible with long-term storage. To address this question, animals were generated by ICSI using a twenty-year-old cryopreserved sperm preparation. Their development, behavior, and reproduction ability were compared with those of animals obtained using a recently frozen sperm preparation and those of animals obtained via IVF using fresh semen. Although lower than with IVF, we showed that fertilization rates using ICSI after 20 years of cryopreservation are similar to those of a recent preparation, with viable offspring leading to normal F2 generation. This pioneering achievement is proof of concept for long-term sperm cryopreservation using simple and readily available technologies for the conservation of endangered amphibians. Full article

The physiological functions of mammalian sperm, such as motility, hyperactivation, and capacitation, require substantial energy. This study investigates the effects of two classic cryopreservation extenders—TCG (tris-citrate-glucose) and LEY (lactose-egg yolk)—on the energy metabolism of frozen–thawed boar semen. By comparing the quality indicators, key metabolite levels, and the activities of critical enzymes involved in glycolysis and the tricarboxylic acid cycle, we aim to understand how these different semen extenders influence the spermatozoa vitality of frozen–thawed boar semen. Following thawing, the LEY-cryopreserved sperm demonstrated significantly elevated motility parameters (viability, VCL, VSL, and VAP) and enhanced plasma membrane and acrosomal integrity compared with the TCG group (p < 0.05), though both cryopreserved groups exhibited significantly reduced performance relative to fresh semen controls. Cryopreservation markedly reduced intracellular adenosine triphosphate (ATP), pyruvate, and acetyl coenzyme A (A-CoA) levels (fresh > LEY > TCG; p < 0.05). The LEY-preserved spermatozoa retained higher activities of glycolysis-related enzymes (phosphofructokinase, PFK; pyruvate kinase, PK) compared with the TCG group, which, in turn, showed elevated lactate dehydrogenase (LDH) activity. Critically, TCG-suppressed pyruvate dehydrogenase (PDH) activity (p < 0.05) coincided with diminished A-CoA, indicating impaired mitochondrial oxidative phosphorylation. These results demonstrate LEY’s superior preservation of motility and membrane stability but highlight cryodamage-induced energy metabolism dysregulation, particularly TCG’s disruption of the glycolysis–TCA cycle coordination essential for spermatozoa function. In conclusion, the choice of semen extender has a significant impact on the energy metabolism and overall quality of frozen–thawed semen, highlighting the importance of optimizing cryopreservation protocols for improved spermatozoa viability and functionality. Full article

Sperm quality is adversely affected by cryopreservation due to the increased production of reactive oxygen species, which affects the integrity of sperm membranes, motility, and DNA fragmentation. Three methods for removing seminal plasma, washing (centrifuging extended semen at 800× g for 10 min) and Single Layer Centrifugation with high or low density Equicoll, were used to prepare 29 ejaculates from ten stallions for freezing. Sperm quality parameters (kinematics, plasma membrane integrity, superoxide and hydrogen peroxide production, mitochondrial membrane potential, and DNA fragmentation) were evaluated before and after freezing using kinematic and flow cytometric analysis. The parameters for fresh samples were within the normal range for stallion semen but were lower after thawing. There were few differences between the three preparation methods. Interestingly, DNA fragmentation was affected most by the sperm preparation method, being lowest for SLC through high density Equicoll, although SLC through low density Equicoll was effective for some stallions. Some differences were observed in the proportions of live or dead spermatozoa positive for hydrogen peroxide. In conclusion, all of these methods would be suitable for the preparation of semen prior to cryopreservation, but Single Layer Centrifugation through high density Equicoll was the most effective in removing spermatozoa with damaged DNA. Full article

Background/Objectives: Male infertility is multifactorial, involving genetic, environmental, lifestyle, and medical factors. Recent research has underscored the influence of lifestyle choices, such as dietary habits, smoking, alcohol abuse, and metabolic disturbances, on sperm quality. In this context, nutrition plays a pivotal role: adherence to a healthy diet like the Mediterranean Diet (MD), which emphasizes seasonal, fresh, and whole foods, has been linked to improved sperm performance. Conversely, a high intake of ultra-processed foods (UPFs), characterized by additives, high levels of sugars, fats, and salt, and a nutrient-poor profile, may impair sperm quality. Methods: Based on data supporting the reproductive health benefits of the MD, this observational cross-sectional study aimed at evaluating the possible relationship between MD adherence, assessed using the 14-point a priori Mediterranean Diet Adherence Screener (MEDAS) and intake of ultra-processed foods (UPFs), based on the NOVA classification, and sperm quality in 358 individuals (mean age 34.6 ± 9.3 years) who spontaneously referred to our center of reproductive medicine. Semen analyses were performed according to the WHO 2021 criteria. Hormonal profiles (FSH, LH, testosterone, SHBG, bioavailable testosterone, and calculated free testosterone) were also determined. Results: MD adherence score was significantly and positively correlated with semen parameters, whilst negatively correlated with FSH and LH levels. In contrast, UPF intake was correlated with poor semen parameters, whilst no association was observed with hormonal levels. Multivariate analyses confirmed these associations and showed the independency from age and BMI. Notably, among men with FSH levels < 8 IU/mL, higher quartiles of UPF intake had lower markers of sperm quality, particularly for viability and typical morphology. Differently, high MD adherence scores were associated with high quality sperm parameters even when FSH levels were >8 IU/mL. Conclusions: This study provides evidence that the adherence to MD, and conversely reduced intake of ultra-processed foods, is associates with a better semen profile. These findings suggest the possible role of dietary interventions as a modifiable factor in the management of male infertility. Full article

The cryopreservation of boar sperm effectively extends its storage period but often leads to increased reactive oxygen species (ROS) production, compromising sperm quality. Plant extracts, rich in bioactive compounds such as polyphenols and flavonoids, have been shown to reduce ROS. Djulis (Chenopodium formosanum), also known as the “ruby of cereals”, is nutritionally rich and holds potential as a cryoprotective additive. This study aimed to determine the optimal concentration of extracts from different parts of djulis, including unhulled seeds and stems, for effective boar semen cryopreservation. Fresh semen from Taiwan indigenous boars was diluted with a modified GLT-cryoprotectant extender containing glycerol, low-density lipoprotein (LDL), and trehalose. The experimental groups included DSS25, DSS50, DS25, and DS50—representing djulis unshelled seed at 25 mg/mL and 50 mg/mL, and djulis stem at 25 mg/mL and 50 mg/mL in distilled water, respectively—alongside a control group without additives. Post-thaw assessments included sperm motility, kinetic parameters, viability, acrosome integrity, and the antioxidant properties of djulis extracts, such as DPPH radical scavenging activity and total phenolic acid content. Results showed that total motility (TM) was significantly higher in the DSS25 (48.8 ± 3.9), DSS50 (49.0 ± 6.7), and DS50 (49.0 ± 2.4) groups compared to the control group (31.3 ± 4.8). Similarly, progressive motility (PM) was significantly improved in DSS25 (27.5 ± 2.7) and DSS50 (26.8 ± 4.1) versus the control (12.8 ± 3.2). However, for straightness (STR), the control group (87.8 ± 1.3) exhibited significantly higher values than the DS50 group (83.5 ± 1.3) (p < 0.05). Viability and acrosome integrity showed no significant differences across groups. In conclusion, djulis extracts positively influence sperm motility and forward movement, with 1% djulis extract confirmed to enhance the quality of cryopreserved semen. Future research will focus on determining the optimal dosage of djulis extract for improved cryopreservation outcomes. Full article

This study evaluated the post-thaw motility and in vitro fertility of ejaculated and epididymal semen from Pantaneiro bulls and characterized cell-free DNA (cfDNA) in fresh seminal plasma. Semen from five bulls was collected via electroejaculation or post-mortem epididymal extraction. Fresh semen parameters and cfDNA concentrations were assessed before cryopreservation. Post-thaw sperm kinetics were evaluated using CASA at 0 and 6 h of incubation, and in vitro embryo development was analyzed following IVF. Data were assessed using ANOVA and logistic regression. Ejaculate samples exhibited more morphological defects than epididymal samples (15.8% vs. 1.8%, p ≤ 0.05). Post-thaw, epididymal semen showed higher total (87.2% vs. 32.4%) and progressive (67.1% vs. 14.4%) motility at 0 h (p ≤ 0.05), and higher motility at 6 h (38.9% vs. 11.0%, p ≤ 0.05). In vitro fertility did not differ significantly between ejaculated (n = 525 oocytes) and epididymal (n = 500 oocytes) semen groups in terms of cleavage (49.6% vs. 44.2%) and blastocyst formation on D7 (26.1% vs. 22.2%, p > 0.05). cfDNA concentration in fresh semen ranged from 11.4 to 50.9 ng/µL. These findings indicate that epididymal sperm from Pantaneiro bulls retain high post-thaw motility and fertility. Additionally, cfDNA characterization in seminal plasma contributes to indigenous cattle preservation and advances in male fertility research. Full article

The study aimed to evaluate the effectiveness of the cryopreservation protocols for Pseudoplatystoma magdaleniatum semen using dimethyl sulfoxide (DMSO) or methanol (MET) as permeable cryoprotectants at two concentrations (5% and 10%) combined with 12% egg yolk (Y12%) or 5% skimmed milk powder (SMP5%) and glucose (6%), resulting in eight treatments. A semen pool (n = 8) was diluted in a 1:4 ratio, packed in 2.5 mL straws, and frozen in nitrogen vapors. It was thawed at 35 °C for 90 s. Sperm kinetics and motility duration of fresh, prefrozen, and thawed semen were analyzed using a CASA system. The osmolarity of seminal plasma and cryosolutions was estimated. Fertilization (F) and embryo viability (E) rates of thawed semen were evaluated. The osmolarity of seminal plasma was 251.1 ± 3.3 mOsmol/kg and, in the cryosolutions, ranged between 1248.3 ± 19.9 mOsmol/kg (DMSO5% + Y12%) and 3488.2 ± 1.5 mOsmol/kg (MET10% + Y12%). After thawing, total motility ranged from 38.2% to 60.5%, representing a significant reduction compared to fresh semen (95.4 ± 2.1%) (p < 0.05). The best fertilization and embryo viability rates of thawed semen were obtained with DMSO5% + SMP 5% (F = 20.7%, E = 11.7%) and MET10% + SMP5% (F = 20.1%, E = 11.5%) (p < 0.05). A cryopreservation protocol for P. magdaleniatum semen with 5%DMSO or 10%MET combined with SMP5% is possible, but further study is necessary to optimize its fertilizing capacity. Full article

Cryopreservation is a widely used technique for long-term semen storage; however, it can induce oxidative stress, compromising sperm quality. This study examines the effect of Kaempferia parviflora (KP) supplementation in semen extenders on the post-thaw sperm quality of Thai native bulls. Fresh semen was collected and evaluated for motility, viability, and concentration prior to cryopreservation. Semen samples were allocated to four treatment groups: 0 mg/mL (control), 0.5 mg/mL, 1 mg/mL, and 1.5 mg/mL KP. Subsequently, the samples were frozen, then thawed, and analyzed for sperm motility, viability, membrane integrity, and oxidative stress. The results showed that supplementation with 1.0 mg/mL KP significantly improved sperm motility (46.29 ± 2.66%) and viability (43.42 ± 2.15%) compared to the control (40.77 ± 2.76% and 38.63 ± 2.66%, respectively). Membrane integrity was also enhanced (47.64 ± 1.18% vs. 41.85 ± 1.98% in the control), while oxidative stress levels were reduced (MDA concentration: 2.33 ± 0.29 µM/mL vs. 2.73 ± 0.33 µM/mL in the control). However, the highest concentration (1.5 mg/mL KP) negatively affected sperm quality, with reduced motility (36.97 ± 3.32%), viability (30.88 ± 3.02%), and membrane integrity (35.64 ± 1.61%). These findings suggest that 1 mg/mL KP is the optimal concentration for improving post-thaw semen quality in cryopreservation protocols for Thai native bulls. Full article

This study investigated the effects of various cryoprotectant combinations on post-thaw sperm quality, biomolecular changes, DNA methylation, and pregnancy rates using Boer goat semen. Synchrotron-based Fourier-transform infrared spectroscopy (SR-FTIR) was used to assess biomolecular changes. A Tris-based extender supplemented with 5% glycerol was used in combination with different concentrations of cryoprotectants, including 1% and 3% soybean lecithin and 10% and 18% egg yolk, with Andromed^® serving as the control. SR-FTIR analysis revealed that the combination of 5% glycerol and 18% egg yolk (T4) resulted in significantly higher levels of lipids, ester lipids, and secondary protein structures (α-helix) compared with those under the other treatments (p < 0.05). Analysis of the principal component analysis (PCA) score plot and correlation loadings revealed a positive association between the cryoprotectant combination of T4 and increased levels of lipids and ester lipids, as well as enhanced sperm motility, progressive motility, and viability. Furthermore, this combination achieved a pregnancy and parturition rate of 66.67%, which was notably higher than the rate achieved with Andromed^® (37.50%). Moreover, T4 did not show a significant difference in DNA methylation levels compared to Andromed^® and fresh sperm (p > 0.05). Overall, the results indicated that specific cryoprotectant combinations play a key role in enhancing the biomolecular and functional integrity of freeze-thawed Boer goat semen. Full article