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Sensitivity to freezing remains a critical issue in stallion semen cryopreservation procedures. To explore this topic in-depth, semen was collected from ten stallions, diluted with three different extenders, transported to the laboratory, and then centrifuged and frozen with four different extenders. We conducted analyses of sperm kinetics, mitochondrial membrane potential (MMP), and hydrogen peroxide content both before and after freezing. Additionally, we assessed antioxidant activity using the ABTS and FRAP methods and measured nitric oxide stable metabolites (NOx) in the blank extenders, seminal plasma, and extenders conditioned by spermatozoa before and after freezing. We found significant variability in the antioxidant activity and NOx content of the blank extenders and the seminal plasma. In the seminal plasma, ABTS-based antioxidant activity and NOx values were correlated with some sperm kinematic parameters and MMP in refrigerated semen, while no correlation was observed in frozen sperm parameters. Sperm function varied significantly between stallions but not between extenders, either before or after freezing. However, significant differences in antioxidant activities and NOx values were found among extenders conditioned following freezing. These results provide new insights into the factors contributing to the variability in individual stallions' tolerance to sperm freezing.

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Addressing the impacts of emerging contaminants within the context of climate change is crucial for understanding ecosystem health decline. Among these, the organic UV-filters 4-methylbenzylidenecamphor (4-MBC) and benzophenone-3 (BP-3) are widely used in cosmetics and personal care products. Their unique physico-chemical properties, along with their growing commercialization and consumption, have made them ubiquitous in aquatic environments through both direct and indirect releases, raising significant concerns about their potential threats to inhabiting biota. Additionally, increasing surface water temperatures exacerbate ecological risks, making it imperative to understand the implications for non-target species at different biological levels. This study investigated the short- and long-term effects of UV-filters 4-MBC or BP-3, at ecologically relevant concentrations, combined with current and predicted warming scenarios, on the performance and male reproductive health of Mytilus galloprovincialis mussel populations. Using biomarkers across sub-cellular, cellular, tissue, and individual levels, the study revealed significant physiological and biochemical impairments in both sperm cells and adults exposed to UV-filters. Temperature emerged as the primary driver influencing mussel responses and modulating the impacts of 4-MBC/BP-3, emphasizing their sensitivity to temperatures outside the optimal range and interactive effects between stressors. Specifically, sperm motility declined with increasing UV-filter concentrations, while temperature alone influenced ROS production, leading to compromised mitochondrial activity and DNA damage in the presence of combined stressors, indicative of potential reproductive impairments. Adults exhibited high UV-filter bioconcentration potential in whole tissues, compromised physiological status, morphophysiological changes in digestive glands, oxidative stress, and alterations in metabolic capacity, antioxidant defences, and biotransformation mechanisms, correlating with UV-filter exposure and temperature increase. Among the UV-filters tested, 4-MBC was the most detrimental, especially when combined with warming. Overall, this study underscores the vulnerability of M. galloprovincialis to cumulative stressors and highlights the importance of employing a multi-biomarker approach to assess and mitigate the impacts of stressors on coastal ecosystems.

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Background: 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. Aim: 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. Methods: 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. Results: 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). Conclusion: 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).

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Background and Aims: Increasing attention is being paid to the role of human papillomavirus (HPV) in men and specifically reproduction. Growing evidence suggests an association between HPV infection with many adverse effects including the impairment of semen parameters, the increase of blastocyst apoptosis, the reduction of endometrial implantation of trophoblastic cells, as well as the increase rate of miscarriages and spontaneous preterm birth. Methods: We systematically searched PubMed/MEDLINE, Scopus, Embase, Web of Science, CINHAL, PsycINFO, and ERIC from inception to 2nd of July 2024, for studies that investigated the association between HPV infection with sperm parameters and fertility outcomes. The meta-analysis was conducted on mean data and standard deviations. Results: We included 25 studies with a total of 6942 patients. Sperm morphology was lower in HPV positive groups versus HPV negative control groups (SMD = -0.52 95% CI -0.84; -0.21; p = 0.001). Sperm motility was also significantly lower in HPV positive groups when compared to HPV negative controls (SMD = -0.82 95% CI -1.07; -0.57; p = <0.001). Sperm volume, concentration, and pH were not significantly different between the two groups. The other 15 studies included in the systematic review for which it was not possible to conduct a meta-analysis showed strong associations between HPV infection and impairment of sperm parameters, reduced couple fertility and increased risk of pregnancy loss. Conclusions: The current evidence highlights the link between HPV infection and sperm parameters, male fertility and reproductive outcomes, which has the potential to lead to a decreased couple fertility, increased risk of pregnancy loss, re-infection and increased treatment costs.

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Introduction: Over the past few decades, there has been growing concern about the concurrent trends of increasing Autism Spectrum Disorder (ASD) prevalence and declining sperm quality. These trends represent significant public health challenges that warrant thorough investigation of their underlying causes and implications. Objectives: The primary objectives of this study are to analyze trends in ASD prevalence and sperm quality parameters from 2000 to 2024, assess the statistical significance and effect size of these trends, explore potential correlations between ASD prevalence and sperm quality parameters, and identify significant predictors among sperm quality parameters that influence ASD prevalence. Methods: This study employed a longitudinal approach using multiple regression, time series analysis, ANOVA, Principal Component Analysis (PCA), hierarchical clustering, logistic regression, and cross-correlation analysis. Data on ASD prevalence were sourced from the CDC Autism and Developmental Disabilities Monitoring Network, while sperm quality data were collected from various published studies. Results: The findings reveal significant negative associations between ASD prevalence and sperm quality parameters such as sperm concentration and motility, suggesting that better sperm quality is linked to lower ASD rates. Conversely, parameters like sperm DNA fragmentation (SDF), volume of ejaculate, pH level, and semen viscosity show positive associations with ASD prevalence, indicating higher values in these parameters correlate with higher ASD rates. Conclusion: The study highlights the importance of maintaining reproductive health to potentially mitigate ASD risk and calls for further research to elucidate the underlying mechanisms driving these trends. These findings support the hypothesis that reproductive health factors play a crucial role in ASD etiology and suggest potential biological markers for assessing ASD risk.

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OBJECTIVE: This study aimed to explore the correlation between ambient particulate matter 2.5 (PM2.5) concentration and sperm quality among northern Thai men exposed to the seasonal air pollution from the agricultural burning process. METHODS: The demographic data and semen analysis of Thai men living in Chiang Mai, Thailand, who visited the infertile clinic were collected. The correlation test between the monthly amount of PM2.5 and sperm quality was carried out. RESULTS: From 2017 to 2021, 1,109 Thai men visited the Infertile Clinic. The correlation test between PM2.5 and sperm quality in years with a better climate revealed a weak positive correlation between the mean PM2.5 and percentage of progressive motile sperm and normal morphology (r=0.08, p=0.05 and r=0.1, p=0.02). However, there was a negative correlation between the mean PM2.5 and sperm concentration, progressive motility and normal sperm morphology during the years with a higher amount of ambient PM2.5, and especially PM2.5 exposure 3 months before semen collection (r=-0.12, p=0.01, r=-0.11, p=0.003, r=-0.15, p=0.004). CONCLUSIONS: Exposure to a high amount of PM2.5 air pollution negatively affects sperm quality.

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Nowadays, changes in human lifestyle have increased dyslipidemia, reinforcing the necessity of using lipid-lowering drugs, such as statins, to control the lipid profile. Among the statins, rosuvastatin has shown greater efficacy in controlling dyslipidemia. Previous studies have shown adverse effects in adult men and pre-pubertal rodents after exposure to statins, such as reduced testosterone levels and delayed puberty. This study aimed to evaluate the reproductive parameters and fertility of male mice exposed to rosuvastatin from pre-puberty to sexual maturity by simulating human chronic exposure to rosuvastatin from pre-puberty to adulthood. This is the first study to evaluate male reproduction and developmental outcomes after prolonged rosuvastatin exposure since pre-puberty, mimicking the human exposure to relevant doses of the drug. Then, we hypothesize that prolonged exposure to rosuvastatin since pre-puberty may impair reproductive parameters in males and generate paternally mediated developmental toxicity. Male mice were divided into three experimental groups that received a 0.9 % saline solution, 1.5 or 5.5 mg/kg/day of rosuvastatin, by intragastric oral gavage, from postnatal day (PND) 23 to PND 80. Puberty onset was delayed and sperm quality was reduced in both rosuvastatin-treated groups. Furthermore, testicular interstitial tissue showed increased vascularization in a dose-dependent manner. After mating with non-treated females, the post-implantation loss rate increased in both rosuvastatin-exposed groups. There was an increase in the percentage of fetuses with opened eyelids in the offspring of males exposed to 1.5 mg/kg/day of the statin and a decrease in the craniocaudal distance of male offspring from males exposed to the higher dose. In summary, our hypothesis that rosuvastatin exposure would cause male reproductive toxicity and developmental impairment in the offspring of male mice was confirmed. This study raises concerns about the reproductive health of men who take this medication from infancy until adulthood in prolonged treatment.

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Dysbiosis, an imbalance in microbial communities, significantly impacts the health and functionality of the human genital tract, with profound implications for fertility and reproductive health. This review explores the intricate relationship between genital tract microbiota and reproductive outcomes, highlighting the composition and dynamics of these microbial communities in both females and males. In females, the vaginal microbiota, primarily dominated by Lactobacillus species, is essential for maintaining a healthy vaginal environment, preventing infections, and supporting reproductive functions. In males, the genital microbiota influences sperm quality and reproductive health. Dysbiosis in the genital tract, manifesting as bacterial vaginosis, yeast infections, urethritis, or prostatitis, disrupts these microbial communities, leading to adverse reproductive outcomes such as infertility, pregnancy, and increased susceptibility to sexually transmitted infections. This review delves into the mechanisms through which dysbiosis affects fertility, including alterations in vaginal pH, mucosal immunity, inflammation, sperm viability, and motility. It also evaluates diagnostic methods, clinical implications, and management strategies, including probiotics, prebiotics, antibiotics, antifungal treatments, lifestyle interventions, and emerging therapeutic approaches. By understanding the microbial landscape of the genital tract and its impact on fertility, this review aims to inform targeted interventions that restore microbial balance and enhance reproductive health, ultimately improving fertility outcomes and the potential for healthy pregnancies.

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Characterization of long non-coding telomeric repeat-containing RNAs in sperm of normozoospermic and oligoasthenozoospermic men as new biomarker of idiopathic male infertility. We conducted an observational prospective study with two groups of men with normal or orligoasthenozoospermic spermiogram, aged 40 and above. Fertility parameters were analyzed in men undergoing intracytoplasmic sperm injection with donor oocytes, to avoid the female factor. Telomeric RNAs and telomere length were measured by quantitative fluorescent in situ hybridization. Data from seminal parameters and in-vitro fertilization were assessed according to IVIRMA protocols. Patients with oligoasthenozoospermia, who had worse seminal parameters, also obtained embryos with lower inner-cell-mass quality (p = 0.04), despite using donor oocytes. While mean levels of telomeric RNAs were similar for both groups, the percentage of spermatozoa with more than 3 foci was higher in oligoasthenozoospermic men (p = 0.02). Regarding telomere length, oligoasthenozoospermic men had shorter mean, a higher accumulation of short telomeres (15th percentile; p = 0.03) and a lower percentage of very-long telomeres (85th percentile; p = 0.01). Finally, a positive correlation was found between telomeric-RNAs intensity and total progressive motility in the spermatozoa of normozoospermic patients (r = 0.5; p = 0.03). Telomeric parameters were altered in the spermatozoa of the oligoasthenozoospermic group, which also showed lower quality embryos. Interestingly, in the normozoospermic group, a correlation was found between progressive motility and telomeric RNA levels, suggesting that they could be a good biomarker of sperm quality. Further studies are required to confirm these results and translate them into the clinical practice.Trial registration number: 1711-MAD-109-CB, 07/07/2021.

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Melatonin is a powerful antioxidant present in fish seminal plasma. This study aimed to understand melatonin's endogenous and exogenous effects on first-generation Senegalese sole sperm quality for sperm management applications. In the first experiment, samples were collected at mid-light (ML) and mid-dark (MD) daytimes, to evaluate the effects on sperm motility. In a second experiment, using confocal microscopy and melatonin-FITC, spermatozoa permeability to melatonin was evaluated and, after showing that it enters the nucleus and mitochondria by passive diffusion, exogenous melatonin toxicity and antioxidant potential during a cryopreservation assay were performed. The toxicity assay tested different melatonin concentrations (0.01, 0.1, 1, and 10 mM) and exposure times (3, 5, 15 and 30 min), and sperm motility parameters were measured (TM, PM, VCL, VSL, LIN) using CASA system. The best conditions (0.1 and 10 mM) were selected for the cryopreservation assay, and a set of post-thaw sperm quality analyses were performed (motility, viability, reactive oxygen species, lipid peroxidation, and DNA fragmentation). The motility analyzed at ML and MD showed significant differences in all parameters, mainly on velocities (VCL, VSL, VAP), that were significantly higher at MD. Supplemented melatonin did not influence spermatozoa motility, MDA content or DNA fragmentation, although a lower percentage of viable cells was obtained on the 10 mM treatment. Altogether, Senegalese sole spermatozoa motility was enhanced at night, putatively by endogenous melatonin through direct or indirect mechanisms, whereas supplemented melatonin did not confer extra protection during cryopreservation.

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During the freezing process of semen, due to the generating of significant amounts of free radicals, the quality of sperm changes. Epigallocatechin-3-gallate (EGCG) is a green tea catechin, which in this study was applied to investigate its effect on the quality of bulls' sperm. We collected semen samples with an artificial vagina from 12 Simmental bulls to evaluate the effect of EGCG (10.00 and 20.00 µmol) in two cryopreserving methods on the quality parameters of semen. We designed six groups including two control groups (method one and two) and four treatments (EGCG 10.00 µmol + method one; EGCG 20.00 µmol + method one; EGCG 10.00 µmol + method two; EGCG 20.00 µmol + method two). The 20.00 µmol EGCG and a method two significantly affected the amending oxidative conditions as well as an increase in total antioxidant capacity and a decrease in malondialdehyde. The effect of EGCG in both concentrations was more on method two. The desired impact on sperm motility, viability, inhibition of lipid peroxidation and sperm DNA damage was observed in EGCG groups compared to control groups. Among the two methods, the method two had fewer adverse effects on the plasma membrane, motility parameters, viability and DNA of sperm. The EGCG in the semen extender yielded a favorable impact on thawed sperm. This effect was prompted in combination with the method two.

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Background: Fertility rates are declining globally, and male infertility is increasingly recognized as a significant challenge. This study aims to present the latest findings on the effectiveness and safety of combining traditional Chinese medicine (TCM) with L-carnitine (LC) for treating male infertility. Methods: We searched 8 databases. Randomized controlled trials of TCM combined with LC therapy versus LC alone in the treatment of male infertility. The outcome included: pregnancy rate, sperm motility, concentration, volume, viability and liquefaction time. Subgroup analyses were also performed according to type of TCM, type of dosage form, and different TCM treatments, and the source of the high heterogeneity was explored. The study is registered on PROSPERO (CRD42023421497). Results: 1129 subjects from 12 of the 1833 eligible studies fulfilled the criteria. Compared with LC treatment alone, the combination of TCM and LC significantly improved pregnancy rate [RR = 1.65, 95 % CI (1.37-2.00)], grade (a+b) sperm motility [SMD = 1.56, 95 % CI (1.12, 2.01)], grade (a) sperm motility [SMD = 1.04, 95 % CI (0.69, 1.38)], sperm concentration [SMD = 1.39, 95 % CI (0.91, 1.86)], and sperm viability [SMD = 1.72, 95 % CI (0.83, 2.60)]. Subgroup analyses indicated that Compound Xuanju Capsule and Yougui Capsule demonstrated better efficacy. And the decoction and not-decoction each had their own advantages. Conclusions: The combination of TCM with LC can have a dual effect: increasing pregnancy rates and sperm quality. Therefore, this combination is a recommended therapeutic strategy and a more appropriate type of TCM can be selected according to the patient's own characteristics.

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Cryopreservation of rooster semen is essential for conserving genetic resources, genetic improvement, and increasing productivity. However, the nature of avian sperm presents a global issue in ensuring superior frozen semen for artificial insemination. Thus, the present study aimed to evaluate the impact of using dimethylacetamide (DMA), dimethyl sulfoxide (DMSO), and ethylene glycol (EG) as cryoprotectants on post-thawed sperm motility, quality, antioxidant indicators, and fertilizing capacity. Twice a week, fresh semen ejaculates were collected from 15 adult roosters and immediately evaluated to constitute a pool from clean and qualified samples. The pooled semen was further diluted at a ratio of 1:2 (v/v) with an extender and then subjected to a freezing protocol in a liquid nitrogen vapor after adding a cryoprotectant solution containing 6% of either DMA, DMSO, or EG, respectively. After thawing, characteristics of sperm motion, quality, antioxidants, and fertilizing ability were evaluated and compared to fresh and cooled semen as controls. The results demonstrated that semen cooling negatively affected some parameters of sperm motility, quality, antioxidant biomarkers, and fertility. In comparison to the DMSO and EG groups, employing DMA considerably (P < 0.05) raised the percentages of sperm progressive motility, viability, plasma membrane intactness, and DNA integrity. The DMA group showed a significant increase in the catalase and glutathione reduced antioxidant enzyme activity and a reduction in nitric oxide and lipid peroxidation. After artificial insemination, the DMA and DMSO groups exhibited considerably (P < 0.05) better rates of hatchability and fertility than the EG group. It is concluded that freezing extenders containing 6% DMA is better than DMSO or EG to improve the post thaw semen quality and fertility in chickens.

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This study aimed to investigate the effect of mitochondria-targeted antioxidants (Mitoquinone, MitoQ) on the quality of frozen-thawed stallion semen. Semen samples collected from three fertile stallions aged 10 - 13 years, were filtered, centrifuged in a skimmed milk-based extender, and diluted to a final concentration of 50 × 106 sperm/mL in freezing medium. Diluted semen was divided into five experimental groups supplemented with MitoQ at concentrations of 0 (control), 25, 50, 100, and 200 nM and then subjected to freezing after cooling and equilibration. After thawing, semen was evaluated for motility and kinetics at different time points. Sperm viability, plasma membrane, acrosome, DNA integrity, mitochondrial membrane potential, apoptosis, and intracellular reactive oxygen species (ROS) concentrations were evaluated. The results revealed that MitoQ at concentrations of 25, 50, and 100 nM improved (P< 0.01) the total sperm motility after 30 minutes of incubation. In addition, 25 nM MitoQ improved the sperm amplitude of lateral head displacement values (P< 0.01) after 30 minutes of incubation. Conversely, negative effects on sperm motility, kinetics, and viability were observed with the highest tested concentration of MitoQ (200 nM). The various concentrations of MitoQ did not affect the plasma membrane, acrosome, and DNA integrity, or the mitochondrial membrane potential and intracellular ROS concentrations. In conclusion, supplementation of MitoQ during cryopreservation, had a mild positive effect on sperm motility and kinetics especially at a concentration of 25 nM, while the highest concentration (200nM) has a detrimental effect on motility and viability parameters of frozen-thawed stallion sperm.

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Past studies have observed that BHPF induces multi-organ toxicity, however, whether it induces damage to male reproductive system and the specific mechanism remains unclear. In the present study, male mice were given 0, 2, 10 or 50 mg/kg/day of BHPF by gavage for 35 days to observe its effect on reproductive organ and sperm quality. The results indicated that BHPF decreased sperm count and sperm motility in a dose-dependent manner. Besides, our results demonstrated that BHPF triggered the proliferation inhibition and cell death of germ cells in vivo and in vitro. Also, BHPF reduced the expression of function markers for germ cells, Sertoli cells, and Leydig cells, indicating its damage to function of testis cells. Simultaneously, testicular microenvironment was found to be altered by BHPF, as presented with declined testosterone level and decreased expression of local microenvironment regulators. Overall, our findings indicated the detrimental effects of BHPF on male reproductive function in mice, suggesting testicular function and local microenvironment disturbance as mechanism underlying testicular damage.

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We demonstrate that tofacitinib does not adversely affect semen quality or sex hormones in male patients. These first postmarketing data for tofacitinib and semen quality are reassuring. Our study raises no safety concerns, though larger studies are needed to confirm our findings.

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PURPOSE: To find the machine learning (ML) method that has the highest accuracy in predicting the semen quality of men based on basic questionnaire data about lifestyle behavior. METHODS: The medical records of men whose semen was analyzed for any reason were collected. Those who had data about their lifestyle behaviors were included in the study. All semen analyses of the men included were evaluated according to the WHO 2021 guideline. All semen analyses were categorized as normozoospermia, oligozoospermia, teratozoospermia, and asthenozoospermia. The Extra Trees Classifier, Average (AVG) Blender, Light Gradient Boosting Machine (LGBM) Classifier, eXtreme Gradient Boosting (XGB) Classifier, Logistic Regression, and Random Forest Classifier techniques were used as ML algorithms. RESULTS: Seven hundred thirty-four men who met the inclusion criteria and had data about lifestyle behavior were included in the study. 356 men (48.5%) had abnormal semen results, 204 (27.7%) showed the presence of oligozoospermia, 193 (26.2%) asthenozoospermia, and 265 (36.1%) teratozoospermia according to the WHO 2021. The AVG Blender model had the highest accuracy and AUC for predicting normozoospermia and teratozoospermia. The Extra Trees Classifier and Random Forest Classifier models achieved the best performance for predicting oligozoospermia and asthenozoospermia, respectively. CONCLUSION: The ML models have the potential to predict semen quality based on lifestyles.

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Background: In recent years, the decline in sperm quality in men has become a global trend. There is a close relationship between sperm quality and pregnancy outcome. There is a large body of literature supporting the role of plasma lipidome in male infertility, while the complex mechanisms between them and male infertility are still less clear. Systematic study of the causal relationship between plasma lipidome and MI can help to provide new therapeutic ideas and targets for male infertility. Methods: In this study, we used a two-sample Mendelian randomization analysis based on Genome-wide association studies pooled data of 179 causal relationships between plasma lipidome and male infertility. We used employed the inverse variance weighted method as the main analysis to assess causality between exposure and outcome, in addition to MR-Egger, Weighted median as complementary methods, and tests for multiplicity and heterogeneity. Results: We identified 13 plasma lipidome comprising 4 types of plasma lipidome that were associated with male infertility. Among these, 9 plasma lipidome were found to be protective factors, while 4 were risk factors. Notably, the largest proportion of these plasma lipidome were triglyceride types, with Sphingomyelin (d40:1) exhibiting the strongest association with male infertility. Conclusion: These findings contribute to the current better understanding of male infertility and provide new perspectives on the underlying etiology of male infertility as well as prevention and treatment strategies. In addition, clinical trial validation is needed to assess the potential of these plasma lipidome as biomarkers.

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A seasonal effect on sperm quality parameters was observed previously. Although identification of the bull semen microbiota by 16S rRNA sequencing was performed previously, it has not been carried out in commercial semen samples from different seasons, and its connection with sperm quality parameters has not been evaluated yet. The objectives in this study were; (i) to evaluate diversity of bull semen microbiota and sperm quality parameters in different seasons, and (ii) to find if specific bacteria were associated with seasonal differences in specific sperm quality parameters. Bull semen microbiota was identified in 54 commercial bull semen samples from 3 seasons (winter, spring, summer). Sperm quality was analysed by Computer Assisted Sperm Analyses (CASA) and Flow Cytometry (FC). From 28 phyla in all samples, six phyla were identified in samples from all seasons, with observed seasonal differences in their distribution. At genus level, 388 genera were identified, of which 22 genera had a relative abundance over 1 % and showed seasonal differences in bacterial diversity, and 9 bacteria genera were present in all seasons. Differences between spring and summer (P < 0.05) were observed for live hydrogen peroxide positive sperm cells. A trend towards significance (0.10 > P > 0.05) was observed for some CASA kinematics (VCL and LIN) and FC parameters (High respiratory activity, and live hydrogen peroxide positive sperm cells) between seasons. Nevertheless, associations between sperm quality parameters and specific bacteria were observed in spring.

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BACKGROUND: Obesity represents a risk in the development of metabolic and oxidative stress (OS), as well as in male infertility. There is still no pharmacological treatment for obesity-induced male infertility, but the use of natural antioxidants has been proposed as a treatment. OBJECTIVE: The aim of this work is to evaluate the effect of a whole tomato lipid extract on rats that decreased their fertility and spermatogenesis after being induced obese with a high carbohydrate diet. MATERIALS AND METHODS: One hundred fourteen male Wistar rats of 12 weeks of age were used. Two groups were randomly formed non-obese control group (C, n = 54) and obese group (Ob, n = 54) that received 30% w/v sucrose solution for 3 months. Subsequently, the C and Ob group were divided into two groups: vehicle (C-Vh and Ob-Vh) that received corn oil as vehicle and tomato lipid extract (C-Ex and Ob-Ex) that received whole tomato lipid extract. The groups that received a hypercaloric diet had a gain in visceral and retroperitoneal adipose tissue, an increase in total cholesterol and triglyceride levels, increased OS in the testis, and lesions in testicular histology, as well as a reduction in testicular size and sperm quality parameters (motility, viability, and concentration). RESULTS: Treatment with whole tomato lipid extract significantly decreased the weight of gonadal adipose tissue and OS, maintained testicular size, showed a significant increase in sperm quality parameters and improved histology of seminiferous tubules. CONCLUSIONS: These results demonstrate a greater therapeutic and beneficial effect of the tomato lipid extract on sperm quality parameters in obese rats and therefore on fertility.