Search Results (620)

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

In remote alpaca breeding regions, access to advanced sperm analysis laboratories is limited. This study validates a practical cytometric method for evaluating sperm viability and acrosomal integrity in epididymal alpaca sperm using early fluorochrome staining, formaldehyde fixation, and intermediate storage. Thirty-two testes were transported at 5 °C, and spermatozoa were collected from the cauda epididymis. After morphometric screening, 26 samples were included. Aliquots were stained with Zombie Green (viability) and FITC–PSA (acrosomal integrity), at time zero. Each aliquot was divided for cytometric analysis at T0 (immediately), T24 (24 h after formaldehyde fixation) and T1w (1 week post-fixation). Fixed samples showed higher viability and acrosomal integrity values (T24: 70.75%, 97.24%; T1w: 71.80%, 97.21%) than T0 (67.63%, 95.89%). This may reflect fluorescence alterations associated with fixation. Strong correlations and Bland–Altman analysis confirmed consistency across time points. This method enables accurate sperm quality evaluation up to one week after collection, offering a useful tool for reproductive monitoring in field conditions without immediate analysis. Further research on ejaculated semen and field protocols is recommended. Full article

High semen quality is vital for reproductive success in the swine industry; however, seasonal fluctuations often compromise this quality. The molecular mechanism underlying these seasonal effects on semen quality remains largely unclear. This study employed untargeted metabolomic profiling of boar seminal plasma (SP) to identify metabolites and metabolic pathways associated with semen quality during the summer and winter months. Semen samples were collected from mature Duroc boars at a commercial boar stud and classified as Passed or Failed based on motility and morphology. SP from five samples per group was analyzed using ultra-high-performance liquid chromatography–mass spectrometry (UHPLC-MS). In total, 373 metabolites were detected in positive ion mode and 478 in negative ion mode. Several differentially expressed metabolites (DEMs) were identified, including ergothioneine, indole-3-methyl acetate, and avocadyne in the summer, as well as LysoPC, dopamine, and betaine in the winter. These metabolites are associated with key sperm functions, including energy metabolism, antioxidant defense, and capacitation. KEGG pathway analysis indicated enrichment in starch and sucrose metabolism, pyrimidine metabolism, and amino acid metabolism across the seasons. Overall, the results reveal that SP metabolomic profiles vary with the season, thereby influencing semen quality. The identified metabolites may serve as potential biomarkers for assessing semen quality and enhancing reproductive efficiency in swine production. Full article

To achieve the goals of productivity and sustainability across diverse livestock systems, reproductive factors play a pivotal role. Historically, reproductive research has primarily focused on females, as they are responsible for maintaining pregnancy and delivering offspring following oocyte fertilization. However, since the early 2000s, the biological significance of sperm RNAs has been increasingly recognized in various livestock species. These RNAs contribute both genetically and epigenetically at the time of fertilization and during early embryonic development. Multiple types of sperm RNA have been identified in bovine, porcine, ovine, buffalo, and caprine spermatozoa. Notably, transcriptomic profiling has shown potential to differentiate between high- and low-fertility males, even when conventional semen quality values appear normal in both groups. This opens the possibility for more accurate identification of highly fertile sires. Nevertheless, a definitive marker or set of markers has yet to be established, likely due to the transcriptome’s sensitivity to environmental conditions and to the variability in evaluation methodologies. Therefore, global scientific efforts should aim to establish standardized, robust protocols, as sperm RNA represents a promising avenue for enhancing the sustainability of animal production systems. 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

Semen cryopreservation is associated with sperm vulnerability to oxidative stress and ice crystal-induced damage, adversely affecting in vitro fertilization (IVF) success. This study aimed to investigate the effects of freezing diluent supplemented with antioxidant limonin (Lim), myo-inositol (MYO), and the ice crystal formation inhibitor L-proline (LP) through sperm motility, morphological integrity, and antioxidant capacity. The Lim (150 mM), MYO (90 mM), and LP (100 mM) significantly ameliorated the quality of post-thaw sperm in Debao boar, and combined treatment of these agents significantly enhanced sperm motility, structural integrity, and antioxidant capacity compared with individual agents (p < 0.05). Notably, the combined use of these agents reduced glycerol concentration in the freezing diluent from 3% to 2%. Meanwhile, the integrity of the sperm plasma membrane, acrosome membrane, and mitochondrial membrane potential was significantly improved (p < 0.05), and the result of IVF revealed the total cell count of the blastocysts was also greater in the 2% glycerol group (p < 0.05). In conclusion, the newly developed freezing diluent for semen, by adding Lim (150 mM), MYO (90 mM), and LP (100 mM), can enhance the quality of frozen–thawed Debao boar sperm and reduce the concentration of glycerol from 3% to 2% as high concentrations of glycerol can impair the quality of thawed sperm and affect in vitro fertilization outcomes. In conclusion, the improved dilution solution formulated demonstrated efficacy in enhancing the quality of porcine spermatozoa following cryopreservation and subsequent thawing. Full article

Lycopene, a carotenoid found in tomatoes and watermelon, has been investigated for its potential to improve male fertility through its antioxidant and anti-inflammatory mechanisms. However, evidence of its effectiveness remains inconsistent. We conducted a systematic review and meta-analysis of studies published until February 2025 in the PubMed, Scopus, Web of Science, and Medline databases. Clinical studies evaluating lycopene supplementation in relation to male fertility outcomes were included in this review. Standardized mean differences (SMDs) were calculated for the key outcomes. Four clinical studies involving 151 participants were included. Lycopene supplementation significantly improved sperm concentration (SMD 0.33, 95% CI [0.02–0.65], p = 0.037) and nonprogressive motility (SMD 0.45, 95% CI [0.04–0.87], p = 0.032). No statistically significant effects were observed on total motility, progressive motility, normal or abnormal morphology, semen volume, or DNA damage. Sensitivity analyses showed that the findings were generally robust, although publication bias and methodological heterogeneity were noted. Lycopene supplementation may offer modest benefits in improving sperm concentration and nonprogressive motility in men. However, evidence for other fertility-related outcomes is inconclusive. Larger, high-quality randomized trials are needed to confirm these findings and clarify the role of lycopene in male reproductive health. 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

In the swine industry, artificial insemination (AI) primarily uses chill-stored semen, making sperm preservation crucial for reproductive success. However, sperm quality declines at varying rates during chilled storage at 17 °C, distinguishing high-survival semen from low-survival semen. This study investigates the metabolomic profiles of boar sperm with different abilities to survive liquid storage. We analyzed sperm motility, kinematics, and morphology in freshly extended (Day 0) and 7-day stored AI semen doses. The AI semen doses were classified as high-motile (HM) or low-motile (LM) based on sperm motility after 7 days of storage (Day 7). Metabolomic data were collected in positive (ESI+) and negative (ESI−) ion modes using a Vanquish Flex UPLC coupled with a Q Extractive Plus. We consistently detected 442 metabolites (251 in ESI+, 167 in ESI−, and 24 in both) across samples and storage durations. In freshly extended and 7-day stored AI doses, we identified 42 and 56 differentially expressed metabolites (DEMs), respectively. A clustering analysis showed significant changes in DEMs between the HM and LM samples. These DEMs were mainly enriched in amino acid metabolism, the pentose phosphate pathway, glycerolipid metabolism, glyoxylate and dicarboxylate metabolism, terpenoid backbone biosynthesis, etc. In summary, this study highlights the metabolomic differences between semen doses with varying abilities to survive liquid storage. Glyceric acid and lysoPC(20:3) emerged as potential markers for sperm preservation. Full article

Semen collection is an important component of conservation and animal husbandry. Semen quality is generally improved using voluntary collection methods, particularly artificial vaginas (AVs). Most commercially available AVs are tube-shaped with few species-specific design augmentations. As genitalia are highly variable across taxa, incorporating species-specific genital morphologies into AV designs may enhance collected semen quality. We compared dolphin semen quality using: (1) silicone bioinspired artificial vaginas (BAVs) that reflect the internal shape of dolphin vaginas, and (2) manual stimulation. Sperm motility and kinematic parameters of five bottlenose dolphins (Tursiops sp.) were assessed using computer-aided sperm analysis (CASA). Sperm collected using BAVs showed non-significant increases in median progressive and rapid motility, and increases in median and mean linear motility, supporting a sexual selection functional hypothesis for the biodiverse vaginal folds unique to whales, dolphins, and porpoises. Sperm concentration decreased with BAV collection, while no consistent trends were detected in volume, pH, velocity, or plasma membrane integrity. Modifications to AVs for other species that incorporate genital morphologies may also optimize collected semen quality for application to artificial insemination. Full article

Infertility is a significant global health concern, and incorporating antioxidants into sperm preparation media is one strategy to enhance sperm quality and decrease infertility rates. This study aimed to investigate the phytochemical compounds of red cotton stamen extracts and their effects as antioxidants in improving the quality of bull frozen semen. Among the extracts, RCU contained the highest levels of total phenolics, total tannins, and total monomeric anthocyanins along with the strongest ABTS free radical scavenging activity and protein denaturation inhibition. Exposing sperm to FeSO₄-induced oxidative stress resulted in significantly reduced motility, viability, and normal morphology. However, treatment with RCD, RCU, and RCM improved these parameters. Additionally, the FeSO₄-induced group showed elevated levels of reactive oxygen species (ROS) and advanced glycation end products (AGEs) compared to the normal control, whereas all red cotton stamen extracts effectively reduced these levels. In conclusion, red cotton stamen extracts, rich in phenolic bioactive compounds, demonstrated strong free radical scavenging capacity and improved sperm motility, viability, and morphology by neutralizing free radicals and enhancing antioxidant defenses. These findings suggest that the red cotton stamen extracts, particularly RCD and RCU, offer benefits for sperm preservation. Full article

Background: Varicocele is a common condition involving the dilation of veins in the scrotum, often linked to male infertility and testicular dysfunction. This study aimed to elucidate the molecular effects of successful varicocele treatment on sperm proteomes following percutaneous sclero-embolization. Methods: High-resolution tandem mass spectrometry was performed for proteomic profiling of pooled sperm lysates from five patients exhibiting improved semen parameters before and after (3 and 6 months) varicocele sclero-embolization. Data were validated by Western blot analysis. Results: Seven proteins were found exclusively in varicocele patients before surgery—such as stathmin, IFT20, selenide, and ADAM21—linked to inflammation and oxidative stress. After sclero-embolization, 55 new proteins emerged, including antioxidant enzymes like selenoprotein P and GPX3. Thioredoxin (TXN) and peroxiredoxin (PRDX3) were upregulated, indicating restoration of key antioxidant pathways. Additionally, the downregulation of some histones and the autophagy-related protein ATG9A suggests a shift toward an improved chromatin organization and a healthier cellular environment post-treatment. Conclusions: Varicocele treatment that improves sperm quality and fertility parameters leads to significant proteome modulation. These changes include reduced oxidative stress and broadly restored sperm maturation. Despite the limited patient cohort analyzed, these preliminary findings provide valuable insights into how varicocele treatment might enhance male fertility and suggest potential biomarkers for improved male infertility treatment strategies. 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

Infertility is a complex and common problem in reproductive medicine consultations. Three factors must be examined during the preconception phase: breeding management, the fertility of the bitch, and the fertility of the stud dog. Among these factors, improper breeding management remains the main cause of reproductive failure, with accurate recognition of ovulation being crucial for successful mating. Artificial insemination allows for a thorough evaluation of semen quality compared to natural mating. In addition, genetic selection, nutritional factors, and reproductive health management can either impair or improve the fertility of females and males. Idiopathic infertility can occur in bitches, but it is important to rule out other possible causes first. In bitches with irregular estrus cycles, ovarian dysfunction and endocrine imbalances should be investigated. In bitches with regular cycles, uterine disorders such as cystic endometrial hyperplasia, endometritis or congenital anomalies may be the cause. Both mating-related and chronic endometritis are recognized as contributing factors to infertility. Infectious agents, particularly Brucella spp. and Mycoplasma spp., should also be evaluated, although interpretation of Mycoplasma test results requires caution. In males presenting with poor semen quality, potential causes include infectious diseases (with brucellosis always requiring exclusion), hormonal imbalances, and the impact of exogenous treatments. The article underscores the critical role of comprehensive diagnostic protocols, proactive health surveillance, and data-driven breeding strategies in systematically addressing this multifaceted challenge. Full article