Higher Sperm Concentration Research Articles

Twenty-year oncology sperm banking experience at a Canadian academic fertility centre: a retrospective study examining the usage and reproductive outcomes from oncology patients

BackgroundMany cancer treatments pose a threat to fertility for patients. Semen cryopreservation before cancer treatment is an effective method to preserve fertility. There are sparse long-term data on the usage...

Quercetin in semen extender curtails reactive oxygen and nitrogen species and improves functional attributes of cryopreserved buck semen

Cryopreservation of goat spermatozoa is challenging due to several factors, including one of the most essential, i.e., oxidative stress. It is particularly essential in goat semen due to its scanty ejaculate volume and high sperm concentration. This leaves a narrow sperm-to-seminal plasma ratio owing to marginal antioxidant support; moreover, semen extension further dilutes the antioxidant level, leading to an imbalance of oxidant-antioxidant equilibrium. The present study aimed to evaluate the effect of quercetin on curtailing oxidative stress and its reflection on the post-thaw survivability and membrane integrity of goat spermatozoa. For this study, six bucks were selected. Six ejaculates from each buck totaling 36 ejaculates were collected, which were then split into five parts; furthermore, each part was added with a semen extender having a particular concentration of additive. Group C without quercetin and T1 containing Vitamin E at 3 mmol/mL were considered the control and positive control respectively, whereas T2, T3, and T4 contain 10, 20, and 30 μmol/mL of Quercetin respectively. The final sperm concentration of each group was kept at 200 × 106 spermatozoa/mL. All groups were subjected to equilibration at 4 °C for 4 h, then filled in French mini (0.25 mL) straws, followed by sealing and cryopreservation. Samples after 72 h of cryopreservation were subjected to evaluation of plasma membrane integrity and viability through staining, acrosomal integrity, and mitochondrial membrane activity through flow cytometry. Evaluation of sperm kinematics as well as the oxidant-antioxidant status of sperm (ROS and nitric oxide) and seminal plasma (SOD, CAT, GPx, FRAP, and lipid peroxidation through MDA estimation) were also carried out. Quercetin, when supplemented at 20 μmol/mL in buck semen extender, significantly (p < 0.01) improved cryopreserved sperm functions in terms of plasma membrane integrity, viability, acrosomal integrity, mitochondrial membrane activity, and sperm kinematics of buck semen. Similarly, Quercetin supplementation at 20 μmol/mL significantly reduced reactive oxygen and nitrogen species (RONS) in sperm and improved the antioxidant status of seminal plasma, which was indicated by reduced oxidative damage and improved the antioxidant status of buck semen. In conclusion, Quercetin at 20 μmol/mL reduced oxidative stress, improved semen antioxidant status, and improved sperm membranes integrity and kinematics.

Effect of season, age and period on semen quality traits in buffalo bulls

ABSTRACT This study investigated the effect of season, age and period on semen traits in buffalo bulls. Data collected during the year 2010–2021 for seven semen traits viz. ejaculate volume (VOL), sperm concentration (SPC), mass activity (MA), initial motility (BFM), post-thaw motility (PTM), number of sperms per ejaculate (NSP) and number of motile sperm (NMSP) from Murrah buffalo bulls (n = 45; aged: 24–75 months). A general mixed model was applied to obtain the R2 value which was the proportion of variation in semen variable. With study period, the highest SPC was obtained during 2012; with the season, the highest VOL (ml) in hot humid and the highest SPC during the hot-dry season and with age, higher VOL, SPC, NSP and NMSP was obtained in older bulls. This study showed that factors i.e. period, season and age had a significant effect on semen traits viz. VOL, MA, SPC, BFM, PTM, NSP and NMSP in buffalo bulls.

Baseline Characterization of Semen from Philippine Native Chickens: Banaba, Joloano, and Paraoakan

The study aimed to characterize and establish baseline data on the quantity and quality of fresh avian semen utilizing a sample of Philippine native roosters. Twenty-two heads each were acquired from breeds Banaba, Joloano, and Paraoakan. The baseline data analysis revealed significant variations in semen volume among different genetic groups, with Banaba displaying the highest volume, followed by Joloano and Paraoakan. Banaba also exhibited the highest semen pH value of 7.27 when compared to the other two genetic groups (P &lt; 0.05). Across various genetic groups of native chickens, the majority of semen samples demonstrated a thick and creamy consistency and color (42.6%), followed by thin and creamy (32.9%), with a statistical significance of P &lt; 0.05. Furthermore, variations in sperm concentration were observed among genetic groups, with Paraoakan having the highest sperm concentration, followed by Banaba and Joloano (P &lt; 0.05). When the semen from Banaba and Joloano native roosters were extended in Ringer’s solution, it exhibited good motility, with more than 50% of spermatozoa in motion, even after six hours of extension. In contrast, the pooled extended semen from Paraoakan native roosters displayed poor motility, particularly after eight hours of extension (P &lt; 0.05). The study also showed that storage temperatures did not significantly affect all the sperm quality parameters of Banaba and Joloano. However, for Paraoakan, samples stored at low temperatures of 5 – 10oC had significantly higher percent motile and progressive sperm, and lower percent static sperm than those stored at room temperature (22 – 25oC) (P &lt; 0.05).

(092) Racial/ethnic Differences in Semen Parameters and Male Reproductive Hormones in the United States: A Systematic Review and Meta-Analysis

Abstract Introduction Semen quality and reproductive hormones are key indicators of male fertility potential, but studies have reported inconsistent results on racial/ethnic differences in these factors in the United States. Objective To perform a meta-analysis evaluating pooled differences in semen analysis parameters and male reproductive hormones across racial/ethnic groups in the United States through a systematic literature search. Methods PubMed, Scopus, and Web of Science were systematically searched up to December 17, 2022, with no language limitation. All studies on racial/ethnic variations in semen parameters and male reproductive hormones among the general population of the United States were included in this meta-analysis. Standardized mean difference (SMD) and its 95% confidence interval (95%CI) between races/ethnicities were pooled using the random-effects model. Newcastle–Ottawa Quality Assessment Scale (NOS) was used for risk of bias assessment. Heterogeneity was assessed by the I2 index. Results Our search yielded 731 articles. After screening, 9 studies were included. These studies had a low risk of bias (NOS ≥ 7) and involved a total of 7,641 participants. The pooled analysis showed no significant differences between White and Black men in the percent of total motility (p-value=0.513; I2=99.76%), total testosterone (p-value=0.272; I2=99.79%), free testosterone (p-value=0.220; I2=99.78%), and estradiol (p-value=0.876; I2=96.90%). However, higher sperm concentration (SMD=3.64; 95%CI: 0.18, 7.09; p-value=0.039; I2=99.53%) and total sperm count (SMD=6.04; 95%CI: 0.09, 11.99; p-value=0.046, I2=99.68%) were estimated for White men compared to Black men. Additionally, higher sperm concentration (SMD=1.39; 95%CI: 0.56, 2.23; p-value=0.001, I2=92.06%) and total motility (SMD=3.06; 95%CI: 0.09, 6.02; p-value=0.043, I2=99.14%) were estimated for Hispanic men compared to non-Hispanic men, with no differences in total sperm count (p-value=0.579, I2=97.79%) or total testosterone (p-value=0.078, I2=95.95%) (Figure 1). Conclusions This meta-analysis demonstrated reductions in semen analysis parameters, especially sperm concentration, for Black and non-Hispanic men relative to White and Hispanic men in the United States. Disclosure No.

Sperm collection in rhinoceros via urethral catheterization

Assisted reproductive technologies are playing an ever-increasing role in the management of ex situ rhinoceros populations. Traditionally, sperm collection in rhinos is conducted via electroejaculation (EEJ) or gamete rescue. Sperm collection via urethral catheterization (UC) is gaining popularity in wildlife reproductive sciences as it requires less specialized equipment, is faster, and less stimulatory than EEJ. This study investigated the use of UC to collect sperm from Southern white (Ceratotherium simum simum; n = 3) and Eastern black (Diceros bicornis michaeli; n = 6) rhinoceros as an alternative or complementary to collection via EEJ. UC samples (n = 14) exhibited high sperm concentration (1.6 ± 0.49 ×109 sperm/mL) and low volume (0.98 ± 0.26 mL). Samples obtained via EEJ (n = 11) were of moderate sperm concentration (0.14 ± 0.05 ×109 sperm/mL) and high volume (30.6 ± 7.2 mL). UC samples were processed for cryopreservation in OptiXcell extender. Motility of UC sperm decreased post-thaw (56 ± 2.4%) over pre-freeze (77.1 ± 3.2%; P < 0.05), with longevity data consistent to prior results published for sperm collected via EEJ. These results suggest sperm quality and cryo-survival are not impacted by the collection method. Since EEJ was conducted after UC, sperm parameters could not be compared between the two methods. Results indicate that UC is a viable alternative to EEJ for sperm collection in rhinoceros.

The effect of Thai ginger (Kaempferia parviflora) extract orally administration on sperm production, semen preservation, and fertility in Thai native chickens under heat stress

Thai indigenous roosters are exposed to unsuitable temperatures and humidity, resulting in a lower reproductive potential. Kaempferia parviflora (KP) extract containing methoxyflavones was fed to roosters to improve their reproductive performance. Thirty-two Thai native roosters were orally administered KP extract at 300, 450, and 600 mg, calculated according to their average body weight, for at least 14 d before semen collection and continued supplementation until the end of the experiment. The nonsupplemented group served as the control. Fresh semen in terms of semen volume, sperm concentration, mass movement score, and sperm viability were evaluated. Semen preservation at 5°C and fertility test were examined for total motility (MOT), progressive motility (PMOT), sperm viability, and lipid peroxidation up to 48 h of storage. Testosterone concentrations and testicular function were also determined. The results showed that the highest sperm concentration and sperm motility of fresh semen were observed in KP extract at 600 mg (P < 0.001). KP extract at 600 mg resulted in higher sperm viability than the control and KP extract at 300 mg (P < 0.05), but was not different from KP at 450 mg (P > 0.05). The highest MOT, PMOT, and viability were found in the roosters that received 600 mg oral KP extract (P < 0.05), while those of the roosters that received oral KP extract 300 mg and the control were the lowest (P < 0.05) at all storage times. Lipid peroxidation was significantly lower in the KP extract up to 24 h (P < 0.05). The fertility and hatchability of the KP extract at 600 mg at T48 showed a minor decrease compared to the control at T0. These results might be inferred as a result of good spermatogenesis, as revealed by the results of histological examination and testosterone activity. In summary, oral administration of 600 mg KP extract improved sperm production and successfully preserved rooster semen for a long duration of up to 48 h of storage.

Monthly variations in semen parameters in a Sri Lankan population undergoing fertility evaluation.

Seasonal variations in semen quality are known to occur in temperate regions, but results regarding tropical areas remain inconclusive. The aim of this study was to determine whether monthly variations in semen parameters are present among men in a tropical region. Data were retrospectively collected from semen analyses of 3,000 men over a 10-year period, from 2012 to 2022. Analysis of variance and the independent-samples t-test were employed to observe variations in semen parameters throughout the entire period and between months, respectively. The mean±standard deviation sperm concentration was significantly lower in June, at 42.5±31.4 million/mL, compared to other months. The highest sperm concentration was found in March, at 57.8±42.6 million/mL, constituting a mean difference of 15.3 million/mL between the lowest and highest concentrations. The total sperm count displayed a similar pattern of monthly variation, with a difference of 47.2 million between the highest and lowest months. No significant monthly differences were observed in other parameters, such as sperm motility, morphology, and semen volume. Significant monthly variations in sperm concentration and total sperm count were evident in this Sri Lankan population. March, which displayed the highest sperm counts, is in the spring in temperate regions, while the month with the lowest counts, July, is part of the summer. Fluctuations in photoperiod appear to most strongly influence these variations.

Chromatin condensation but not DNA integrity of pig sperm is greater in the sperm-rich fraction

BackgroundProtamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo development. In some mammals, like pigs, ejaculates are emitted in three separate fractions: pre-sperm, sperm-rich (SRF) and post sperm-rich (PSRF). These fractions are known to vary in volume, sperm concentration and quality, as well as in the origin and composition of seminal plasma (SP), with differences being also observed within the SRF one. Yet, whether disparities in the DNA integrity and chromatin condensation and protamination of their sperm exist has not been interrogated.ResultsThis study determined chromatin protamination (Chromomycin A3 test, CMA3), condensation (Dibromobimane test, DBB), and DNA integrity (Comet assay) in the pig sperm contained in the first 10 mL of the SRF (SRF-P1), the remaining portion of the sperm-rich fraction (SRF-P2), and the post sperm-rich fraction (PSRF). While chromatin protamination was found to be similar between the different ejaculate fractions (P > 0.05), chromatin condensation was seen to be greater in SRF-P1 and SRF-P2 than in the PSRF (P = 0.018 and P = 0.004, respectively). Regarding DNA integrity, no differences between fractions were observed (P > 0.05). As the SRF-P1 has the highest sperm concentration and ejaculate fractions are known to differ in antioxidant composition, the oxidative stress index (OSi) in SP, calculated as total oxidant activity divided by total antioxidant capacity, was tested and confirmed to be higher in the SRF-P1 than in SRF-P2 and PSRF (0.42 ± 0.06 vs. 0.23 ± 0.09 and 0.08 ± 0.00, respectively; P < 0.01); this index, in addition, was observed to be correlated to the sperm concentration of each fraction (Rs = 0.973; P < 0.001).ConclusionWhile sperm DNA integrity was not found to differ between ejaculate fractions, SRF-P1 and SRF-P2 were observed to exhibit greater chromatin condensation than the PSRF. This could be related to the OSi of each fraction.

Fertilisation kinetics among common Indo-Pacific broadcast spawning corals with distinct and shared functional traits

Indo-Pacific corals predominantly reproduce using synchronous mass spawning events to maximise fertilisation. However, as disturbances continue to thin population densities, the quantities of gametes released declines and colonies become more isolated, reducing the likelihood of cross-fertilisation. Local hydrodynamic conditions can promote or inhibit gamete contact; thus, the interaction between the abiotic environment and sperm density will determine the amount of time gametes interact. In this study, we investigated the sensitivity of reproduction to manipulations of two key limiting factors of fertilisation: sperm concentration and contact time between gametes. We explored fertilisation kinetics of phylogenetically and functionally similar and diverse coral taxa on the Great Barrier Reef and Western Australia (Acropora digitifera, A. tenuis; Coelastrea aspera, Platygyra daedalea). Results indicate that fertilisation is optimised at sperm concentrations > 103 sperm mL−1 and contact times > 30 s, but the extent of these relationships is species-specific. All species showed clear differences in fertilisation success across contact times, although these differences were less distinct for A. tenuis and P. daedalea at very high sperm concentrations. Acropora digitifera and P. daedalea exhibited nonlinear trends with steep slopes of increased fertilisation success once sperm concentration surpassed values of 104 sperm mL−1 and 102 sperm mL−1, respectively, followed by slight declines. Acropora tenuis and A. digitifera had the highest maximum fertilisation success, likely owing to beneficial evolved functional traits like large egg sizes. The present analysis underpins studies of fertilisation kinetics in natural reef populations to help inform management and restoration practices that assist population resilience and recovery.

Oxido-Reduction Potential as a Method to Determine Oxidative Stress in Semen Samples.

There are different estimates for the incidence of infertility. Its occurrence may vary from area to area, but on average, it affects 15% of couples and 10-12% of men worldwide. Many aspects of infertility can be linked to reactive oxygen species (ROS) and the process of oxidative stress (OS). The association between poor semen quality and OS is well known. Unfortunately, there is no accepted protocol for the diagnosis and treatment of OS in andrology. Oxido-reduction potential (ORP) measurement is a new method for determining the ratio between oxidant and antioxidant molecules. Currently, ORP measurement is one of the fastest and most user-friendly methods of andrological OS determination and our goals were to confirm published correlations between ORP values and sperm parameters, examine how sperm concentration influences these results, and investigate whether intracellular ROS formations are also manifested in the ORP values or not after artificial ROS induction. Intracellular ROS formations were induced by menadione (superoxide anion inducer), hydrogen peroxide, and tert-butyl hydroperoxide (lipid peroxidation inducer) treatments; sperm parameters like motility and viability were determined with an SCA Scope system, and ORP changes were recorded by the Mioxsys system. Significant correlations were noticed among the ORP, spermatozoa concentration, motility, progressive motility, and viability. Nevertheless, only the ORP value after normalization with the sperm count correlated with these parameters. Due to normalization, very low and very high sperm concentrations can give misleading results. The means of the non-normalized ORP values were almost the same. All of the applied treatments resulted in decreases in the viability, motility, and progressive motility, and interestingly, altered ORP levels were detected. In addition, it was determined that seminal plasma had a significant protective effect on spermatozoa. The elimination of seminal plasma caused higher sensitivity of spermatozoa against used OS inducers, and higher ORP levels and decreased viabilities and motilities were measured. The ORP level could be a good indicator of male OS; however, in cases of low and high sperm counts, its result can be misleading. Overall, the conclusion can be drawn that ORP determination is a suitable method for detecting intracellular ROS accumulation, but it has limitations that still need to be clarified.

Production Performance and Sperm Characteristics of Quail (Coturnix-coturnix japonica) with Different Concentrations of Yolk Immunoglobulin

Quails are classified according to their immunity to different IgY concentrations. Quail IgY concentrations range from 0 to 1200 µg ml-1, and these IgY concentrations may affect production and reproductive performance. This study aimed to analyze IgY concentrations in male quail and to compare production and reproductive performance at different IgY concentrations. Forty-two male quail at five weeks of age participated in the study, including 29 quail with low IgY concentration (210-393 µg ml-1)  and, 13 with intermediate IgY concentration (403-564 µg ml-1). The observed productive performances were feed intake, initial body weight, final body weight, weight gain, feed conversion, morbidity, and mortality. In addition, this study observed testicular weight and macroscopic and microscopic semen quality for reproductive traits. Differences in production and reproductive performance of each group were analyzed using an independent-sample t-test. The result showed that male quail with different IgY concentrations were equal in all productive traits (P0.05). This means that male quail with low IgY and medium IgY concentrations are equally good. Testicular weight, semen color and pH were identical at different IgY concentrations. Quails with low IgY concentrations have better sperm consistency, which is related to the weight of the testes, which are heavier in quails with low IgY concentrations than in those with moderate IgY concentrations. This consistency is related to the concentration of sperm in the semen. The result concludes IgY concentrations in male quail did not affect production performance. Quails with low IgY concentration had thicker sperm consistency and higher sperm concentration.

Sperm competition experiments reveal low prezygotic postmating isolation between parasitic and nonparasitic lamprey ecotypes.

The role of postmating sexual selection as a potential reproductive barrier in speciation is not well understood. Here, we studied the effects of sperm competition and cryptic female choice as putative postmating barriers in two lamprey ecotypes with a partial reproductive isolation. The European river lamprey Lampetra fluviatilis is anadromous and parasitic of other fish species, whereas the brook lamprey Lampetra planeri is freshwater resident and nonparasitic. We measured sperm traits in both ecotypes and designed sperm competition experiments to test the occurrence of cryptic female choice. We also performed sperm competition experiments either at equal semen volume or equal sperm number to investigate the role of sperm velocity on fertilization success. We observed distinct sperm traits between ecotypes with a higher sperm concentration and a lower sperm velocity for L. planeri compared with L. fluviatilis. The outcomes of sperm competition reflected these differences in sperm traits, and there was no evidence for cryptic female choice irrespective of female ecotype. At equal semen volume, L. planeri males had a higher fertilization success than L. fluviatilis and vice versa at equal sperm number. Our results demonstrate that different sperm traits between ecotypes can influence the male reproductive success and thus gene flow between L. planeri and L. fluviatilis. However, postmating prezygotic barriers are absent and thus cannot explain the partial reproductive isolation between ecotypes.

Incorporation of fresh leaves of wormwood (Artemisia herba alba) and/or rosemary (Rosmarinus officinalis) in the diet of rams: Effect on testicular function, sexual behavior, and blood parameters.

This study aimed to investigate the effect of wormwood and rosemary supplementation on some reproductive traits of Barbarine rams. The experiment lasted 2 months. Twenty-four adult rams were divided into four groups (n=6) balanced for the weight (53.3 ± 1.2 kg body weight [BW] ± SD). All rams received 1200 g of straw and 600 g of barley. Control rams (C) without aromatic medicinal plant (AMP), while experimental rams received 20 g of fresh rosemary leaves (R), 20 g of fresh wormwood leaves (A), and 10 g of fresh rosemary leaves plus 10 g of fresh wormwood leaves (RA). The results revealed that the live weight of all rams increased (p < .05) in the RA group compared to the C, A, and R groups. Scrotal circumference increased in the R rams when compared to the controls rams (p < .05). For sperm parameters we showed that the A rams had higher sperm concentrations (p < .05). But, the sperm volume decreased in the R rams (p > .05). However, when the rams received rosemary plus wormwood, their sperm volume increased (p > .05). The sperm mass motility was higher for the A, R and AR rams in comparison to the C rams (p=.05). On the other hand, biochemical analysis of the seminal fluid showed no effect of diets on calcium and total proteins concentration. But the measurement of glucose and seminal insulin showed a decrease (p < .05) in these two biochemical markers in group A rams and a decrease (p < .05) in insulin without modification of the glucose concentration in R rams. Blood glucose and insulin decreased in the animals on AMP diet compared to the other groups (p < .05) while aspartate aminotransferase (AST) increased (p < .05). Rosemary leaves (R and RA groups) increased (p < .05) plasma cortisol compared to the other groups. It can be concluded that the addition of Rosmarinus officinalis and/or Artemisia herba alba in ram diet can have a positive effect on the reproductive function by increasing the concentration and motility of sperm, plasma testosterone, and sexual behavior.

Machine learning-based clustering to identify the combined effect of the DNA fragmentation index and conventional semen parameters on in vitro fertilization outcomes

BackgroundPrevious studies have demonstrated an association between male sperm quality and assisted reproduction outcomes, focusing on the effects of individual parameters and reaching controversial conclusions. The WHO 6th edition manual highlights a new semen assay, the sperm DNA fragmentation index, for use after routine semen examination. However, the combined effect of the sperm DNA fragmentation index (DFI) and routine semen parameters remains largely unknown.MethodsWe assessed the combined effect of the sperm DFI and conventional semen parameters on single fresh conventional IVF outcomes for infertile couples from January 1, 2017, to December 31, 2020. IVF outcomes were obtained from the cohort database follow-up records of the Clinical Reproductive Medicine Management System of the Third Affiliated Hospital of Guangzhou Medical University. An unsupervised K-means clustering method was applied to classify participants into several coexposure pattern groups. A multivariate logistic regression model was used for statistical analysis.ResultsA total of 549 live births among 1258 couples occurred during the follow-up period. A linear exposure–response relationship was observed among the sperm DFI, sperm motility, and IVF outcomes. In multivariable adjustment, increased sperm DFI values and decreased sperm motility and semen concentration levels were associated with reduced odds of favourable IVF outcomes. Four coexposure patterns were generated based on the sperm DFI and the studied semen parameters, as follows: Cluster 1 (low sperm DFI values and high sperm motility and semen concentration levels), Cluster 2 (low sperm DFI values and moderate sperm motility and semen concentration levels), Cluster 3 (low sperm DFI values and low sperm motility and semen concentration levels) and Cluster 4 (high sperm DFI values and low sperm motility and semen concentration levels). Compared with those in Cluster 1, participants in Cluster 3 and Cluster 4 had lower odds of a live birth outcome, with odds ratios (95% confidence intervals [CIs]) of 0.733 (0.537, 0.998) and 0.620 (0.394, 0.967), respectively.ConclusionsWhen combined with low sperm DFI values, there was no significant difference between high or moderate sperm concentration and motility levels, and both were associated with favourable IVF outcomes. Low sperm parameter levels, even when DFI values remain low, may still lead to poor IVF outcomes. Participants with high sperm DFI values and low sperm motility and semen concentration levels had the worst outcomes. Our findings offer a novel perspective for exploring the joint effects of sperm DFI and routine semen parameter values.

Spermatozoa Cryopreservation of Sex-Reversed Rainbow Trout (Oncorhynchus mykiss): The Effect of Dilution Rate and Supplementation of a N-(2-Mercaptopropionyl)-Glycine -Based Extender on Sperm Motility and Fertilizing Capacity

For commercial aquaculture, the obtainment of all-female salmonid populations is important in fish farms. After freezing process, variable spermatozoa maturity, higher sperm concentration, low sperm quality, and reduced fertilization success have been observed in sex-reversed female rainbow trout. For these reasons, the objective of this study was to assess effect of dilution rate and supplementation of a N-(2-Mercaptopropionyl)-Glycine (MPG)-based extender on sperm motility and fertilizing capacity of sex-reversed rainbow trout (Oncorhynchus mykiss). The supplementation of MPG [0 (control, 0), 1 mM; 2 mM; 4 mM] to extenders and dilution ratio (1:9, 1:15 and 1:25) were tested in sex-reversed female rainbow trout spermatozoa during cryopreservation. For thawing, the straws (0.5 ml) were placed in a water bath at 37°C for 30 s. Our results showed that the best concentration of MPG was 2 mM for post-thaw motility duration (120.67±9.07%), fertilization (62.67±3.10%) and hatching rate (54.33±3.10%) at 1:15 dilution rate. Overall, MPG provided improvements during cryopreservation process and could be used as protective agent.

Influence of Semen Collection Frequency and Seasonal Variations on Fresh and Frozen Semen Quality in Thai Native Roosters

This study aimed to determine the effects of the frequency of semen collection (once, twice, and thrice weekly) and seasonal variations on the fresh and frozen semen quality of Thai native roosters throughout the year. Data on temperature and humidity were collected and used to calculate the temperature-humidity index (THI). The average temperature and THI were lower in the winter than in the rainy season and the summer (p < 0.05). In contrast, the average relative humidity was not different among the seasons but was higher in the rainy season (p > 0.05). None of the fresh or frozen semen quality parameters were influenced by the frequency of semen collection, but the season did have an effect. The highest sperm concentration was obtained in the winter (p < 0.05). In contrast, the lowest sperm concentration was found during the rainy season, which presented the highest humidity. Regarding the frozen semen quality, the highest malondialdehyde concentration and the lowest motility were found in the summer (p < 0.05). In conclusion, semen collection can be conducted thrice per week for a consecutive year without affecting semen quality while maximizing sperm production. However, the highest sperm production was obtained in the winter, which is also a suitable season for producing semen for cryopreservation.

Sperm mitochondrial DNA copy number mediates the association between seminal plasma selenium concentrations and semen quality among healthy men

Selenium (Se) is essential for successful male reproduction. However, the association of Se status with human semen quality remains controversial and the underlying mechanisms are poorly understood. We measured seminal plasma Se concentrations, sperm mitochondrial DNA copy number (mtDNAcn), and sperm quality parameters among healthy Chinese men screened as potential sperm donors. Linear mixed-effects models were used to investigate the associations of within-subject pooled seminal plasma Se concentrations (n = 1159) with repeated sperm quality parameters (n = 5617); mediation analyses were applied to evaluate the mediating role of sperm mtDNAcn (n = 989). Seminal plasma Se concentrations were positively associated with sperm concentration and total count (both P for trend < 0.001). In adjusted models, men in the top vs. bottom quartiles of seminal plasma Se concentrations had 70.1 % (95 % CI: 53.3 %, 88.9 %) and 59.1 % (95 % CI: 40.5 %, 80.2 %) higher sperm concentration and total count, respectively. Meanwhile, we observed inverse associations between seminal plasma Se concentrations and sperm mtDNAcn, and between sperm mtDNAcn and sperm motility, concentration, and total count (all P for trend < 0.05). Mediation analyses suggested that sperm mtDNAcn mediated 19.7 % (95 % CI: 15.9 %, 25.3 %) and 23.1 % (95 % CI: 17.4 %, 33.4 %) of the associations between seminal plasma Se concentrations and sperm concentration and total count, respectively. Our findings suggest that Se is essential for male spermatogenesis, potentially by affecting sperm mtDNAcn.

ФИЗИОЛОГИЧЕСКИЕ ОСОБЕННОСТИ НАТИВНОЙ И ДЕКОНСЕРВИРОВАННОЙ СПЕРМЫ КОТОВ С РАЗНЫМ АНТИГЕННЫМ ПРОФИЛЕМ ЭРИТРОЦИТОВ

The presence of antisperm antibodies in the blood and secretions of the genital tract can inhibit the interaction of spermatozoa with eggs, and they can inhibit the development of zygotes after fertilization. Therefore, the identification and study of antigens that can reduce reproductive function is of great importance for understanding their relationship with infertility and with antisperm antibodies. The physiological features of native and frozen-thawed sperm of cats with different antigenic profile of erythrocytes by blood groups were established. The mobility of native spermatozoa was the lowest in cats of blood group AB, which is 6.45% less (P&lt;0.001) than the mobility of spermatozoa in animals with blood group A and 6.73% less (P&lt;0.001) than the activity of spermatozoa in cats with the blood group blood B. The concentration in all ejaculates was from 78 to 425 million / ml. The highest sperm concentration was in cats with blood type AB, which is 0.64 million/ml more than in blood group B and 32.57 million/ml more (P&lt;0.01) in cats with blood type A. The largest number of pathological forms of spermatozoa were found by us in cats with blood type AB, which is 4.34% more (P&lt;0.05) from blood group A and 5.15% more (P&lt;0.05) from cats with blood type B. The data obtained allow us to conclude that for the creation of cryobanks of sperm production, cats with blood type A or B are most desirable. blood group B and 5.55% more (P&lt;0.01) from animals with blood group AB. The data obtained allow us to state that the physiological usefulness of germ cells of cats of Russian selection is better in cats with blood type A or B. hours more (P&lt;0.05) from blood group B and 0.68 hours more (P&lt;0.001) from animals of blood group AB.

The Influence of Body Weight on Semen Parameters in Apis mellifera Drones.

The quantity and quality of the honey bee drone semen have a significant determination on the performance of bee colonies. The existence of a smaller number of mature drones to participate in the mating of queens, as well as a sufficient number of drones but with poor quality semen can have serious implications for the productivity of bee colonies. Our study aimed to investigate the correlation between two body weight ranges of drones and semen parameters in the Buckfast honey bee, data that could be integrated into the optimization of instrumental insemination in been queens. Semen was collected from two groups of drones with different body weights (200-240 mg and 240-280 mg). Semen volume, semen concentration, motility, morphology and membrane integrity of spermatozoa were analyzed. The phenotype indicator related to body weight in correlation with the main semen parameters studied gives a weak influence or causality ratio. In drones with 240-280 mg body weight, a higher percentage of spermatozoa with abnormal morphology (&gt;9.60%) was recorded, compared to drones with 200-240 mg body weight. The study reveals that a higher weight of honey bee drones is correlated with higher sperm concentration and total number of spermatozoa/ejaculate, with an increase in the percentage of spermatozoa with abnormal morphology.