Pressure flow pattern of varicocele veins and its correlation with testicular blood flow and semen parameters

The pressure pattern in varicocele veins of infertile patients and its correlation with semen quality and testicular blood flow was determined. Consecutive patients at andro‐urology clinic of a teaching hospital undergoing microsurgical varicocelectomy were included. Their semen quality and testicular blood flow were determined. Peak systolic velocity (PSV) and resistive index (RI) of subcapsular and intraparenchymal branches of testicular artery were noted by colour Doppler ultrasonography. During surgery before ligation of varicocele veins, intravenous pressures of internal spermatic (ISV) and external spermatic (ESV) veins were determined at baseline and after Valsalva manoeuvre. Thirty patients, 20–45 years old, were evaluated. Baseline pressure for maximum dilated ISV (A), less dilated ISV (B) and ESV was 15.93 ± 6.34, 12.38 ± 4.60 and 12.92 ± 5.65 mm. Hg, respectively, which increased after Valsalva by 104.4%, 116.2% and 38.22% respectively. Correlation (r = ?.71; p < .05) was appreciated between percentage increase in pressure of ISV B with PSV of intraparenchymal testicular arteries and progressive motility (r = ?.759; p < .05), nonprogressive motility (r = ?.738; p < .05) and morphology (r = ?.653; p = .07) of spermatozoa. In conclusion, ISV develops higher pressure on Valsalva as compared to ESV and has correlation with semen quality and testicular blood flow.     

Association of seminal angiotensinogen with sperm motility and morphology in male infertility

Many researchers have shown that renin–angiotensin system (RAS) is involved in various important aspects of male reproduction. In this study, we assessed whether abnormal levels of seminal angiotensinogen (AGT) may be associated with semen parameters in infertile males. A total of 115 male patients were recruited, and semen parameters, seminal AGT and the electrolytes including K⁺, Na⁺, Cl^?, P and Ca were evaluated. According to the World Health Organization (WHO) 2010 criteria, the patients were divided into two groups: G1 group with normal semen parameters (n = 42) and G2 group with subnormal semen parameters (n = 73). The level of seminal AGT was significantly higher in G2 group compared with G1 group. Moreover, the level of AGT was negatively correlated with the percentage of total motility (r = ?.322, p = .000), progressive motility (PR) (r = ?.339, p = .000) and morphologically normal forms (r = ?.263, p = .004). This study suggests that elevated seminal AGT level is associated with increased risk of asthenospermia and teratozoospermia.     

Sperm telomere length in motile sperm selection techniques: A qFISH approach

Several studies have associated telomere shortening with alterations in reproductive function. The objective of the present study was to determine telomere length (TL) in spermatozoa selected by either density‐gradient centrifugation (DGC) or swim‐up. The analysis of TL was performed using quantitative fluorescent in situ hybridisation (qFISH) using PNA probes in combination with a chromatin decompaction protocol in sperm cells. Results of TL were 24.64 ± 5.00 Kb and 24.95 ± 4.60 Kb before and after DGC, respectively, and 19.59 ± 8.02 Kb and 20.22 ± 5.18 Kb before and after swim‐up respectively. Sperm selected by DGC or swim‐up did not show any significant differences in TL as compared to nonselected sperm (p > .05). Negative correlations between TL and sperm motility (r = ?.308; p = .049) and concentration (r = ?.353; p = .028) were found. Furthermore, exposure of sperm to increasing concentrations of hydrogen peroxide during incubation resulted in a reduction in TL. These data indicate that oxidative stress may be one of the main factors involved in the reduction of TL in sperm. Preliminary clinical results from patients included in this study indicate that TL was shorter in spermatozoa from couples who never achieved a pregnancy compared to couples who did achieve at least one natural pregnancy (p < .05); however, the clinical utility of this biomarker still needs to be confirmed in further studies.     

Effect of Coenzyme Q10 supplementation on antioxidant enzymes activity and oxidative stress of seminal plasma: a double‐blind randomised clinical trial

Low seminal plasma concentrations of coenzyme Q10 (CoQ10) have been correlated with impaired sperm parameters, but the exact mechanism remains of dominating interest. This randomised, placebo‐controlled study examined the effect of CoQ10 on catalase, superoxide dismutase (SOD) and F₂‐isoprostanes in seminal plasma in infertile men and their relation with CoQ10 concentration. Sixty infertile men with idiopathic oligoasthenoteratozoospermia (OAT) were randomised to receive 200 mg d^?1 of CoQ10 or placebo for 3 months. 47 persons of them completed the study. Semen analysis, anthropometric measurements, diet and physical activity assessment were performed for subjects before and after treatment. Independent and paired t‐test, chi‐square test and ancova were compared outcomes of supplementation between two groups. CoQ10 levels increased from 44.74 ± 36.47 to 68.17 ± 42.41 ng ml^?1 following supplementation in CoQ10 (P < 0.001). CoQ10 group had higher catalase and SOD activity than the placebo group. There was a significant positive correlation between CoQ10 concentration and normal sperm morphology (P = 0.037), catalase (P = 0.041) and SOD (P < 0.001). Significant difference was shown between the mean of changes in seminal plasma 8‐isoprostane in two groups (P = 0.003) after supplementation. Three‐month supplementation with CoQ10 in OAT infertile men can attenuate oxidative stress in seminal plasma and improve semen parameters and antioxidant enzymes activity.     

Evaluation of the role of L-arginine on spermatological parameters,seminal plasma nitric oxide levels and arginase enzyme activities in rams

The purpose of this study is to investigate the effects of L-arginine on spermatological parameters, seminal plasma nitric oxide levels and arginase enzyme activities. Fertile rams that are 2–3 years old and weighing 50–60 kg were used as material. The semen was collected by artificial vagina at 1st, 4th, 24th, 48th, 72nd, 96th and 120th hours for the control group before L-arginine administration. For treatment groups, L-arginine was administered intraperitoneally at a dose of 5 mg kg⁻¹ bw⁻¹ and semen was collected at the time point described for the control group. Spermatological characteristics of semen samples (semen volume, pH, sperm motility, concentration and abnormal sperm rate), seminal plasma nitric oxide levels and arginase enzyme activities were determined. Increased seminal plasma nitric oxide level (p < .01), seminal plasma arginase activity (p < .01), semen volume (p < .05), semen mass activity (p < .05), sperm motility (p < .05) and concentration (p < .01) and decreased abnormal sperm rate (p < .05 and p < .01) were observed by L-arginine administration. In conclusion, it may be concluded that L-arginine application in rams during the breeding season may have positive effects on rams' reproductive performance.     

Decreased prostate-specific membrane antigen levels in the seminal plasma of oligoasthenoteratozoospermic men

Prostate-specific membrane antigen (PSMA) is a transmembrane glycoprotein with glutamate carboxypeptidase activity. However, its precise function in the prostate, prostasomes and seminal plasma with regard to male fertility remains unknown. This study was conducted to investigate the seminal plasma PSMA levels in fertile men and patients with oligoasthenoteratozoospermia (OAT) and to analyse its association with sperm parameters. Twenty fertile men and twenty patients admitted at the urology clinic of our institution with the diagnosis of OAT were included in the study. Following semen analysis, seminal plasma was isolated from semen ejaculates. PSMA concentrations in the seminal plasma were determined by ELISA. The correlations between seminal PSMA concentrations and semen parameters were statistically analysed. Seminal plasma PSMA concentration was significantly lower in OAT patients compared to fertile controls (p < .01). In fertile men, PSMA concentration was significantly correlated with the sperm concentration (r = −.481, p < .05), whereas in the patient group no statistically significant correlation was found between the sperm parameters and seminal PSMA level. This is the first study in the literature to investigate PSMA levels in the seminal plasma from infertile men. Decreased levels of seminal plasma PSMA might suggest a role for compromised prostasome function in the pathogenesis of OAT syndrome.     

Is there any correlation between sperm parameters and chromatin quality with embryo morphokinetics in patients with male infertility?

The main goal was to evaluate the correlation between sperm parameters and chromatin quality with embryo kinetics via time‐lapse monitoring system (TLM). A total of 40 couples involved in the ICSI program as a result of male infertility. For assessment of sperm chromatin and DNA quality, we used aniline blue, toluidine blue, chromomycin A3, acridine orange and terminal transferase‐mediated deoxyuridine triphosphate biotin end labelling assays. All mature oocytes were injected, and the generated zygotes (2PNs) were cultured in TLM. In day 3 after injection, single embryo transfer (SET) was carried out according to the morphology and morphokinetics. The patients were followed up until delivery. There were positive significant correlations between sperm count with CC2 (r = .330, p = .049), T4 (r = .329, p = .038), T6 (r = .342, p = .035) and T7 (r = .374, p = .025). Also, there were positive significant correlations between nonprogressive motility and T2 (r = 0.323, p = .042), T3 (r = .411, p = .013) and T4 (r = .418, p = .007). Regarding the sperm chromatin quality assays, there were negative significant correlations between CMA3 and CC2 (r = ?.272, p = .049) and between acridine orange and T5 (r = ?.221, p = .040). It seems that the abnormal sperm parameters and chromatin alteration affect the normal embryo kinetics in ICSI program.     

Toxic effects of arsenic on semen and hormonal profile and their amelioration with vitamin E in Teddy goat bucks

The present environmental study has been planned to investigate the toxic effects of arsenic on reproductive functions of Teddy bucks as well as to examine whether these toxic effects are ameliorated by vitamin E. Sixteen adult Teddy bucks were divided randomly into four equal groups A, B, C and D with following treatment: A (control), B (sodium arsenite 5 mg kg^?1 BW day^?1), C (vit E 200 mg kg^?1 BW day^?1 + Arsenic 5 mg kg^?1 BW day^?1) and D (vit E 200 mg kg^?1 BW day^?1). This treatment was continued for 84 days. Semen quality parameters were evaluated weekly. Male testosterone, luteinising hormone (LH), follicle‐stimulating hormone (FSH) and cortisol levels were measured through enzyme‐linked immunosorbent assay (ELISA) after every 2 weeks. The data were subjected to two‐way analysis of variance followed by Duncan test for multiple comparisons. Semen evaluation parameters were reduced significantly (P < 0.05) in arsenic‐treated animals. The serum hormonal profile of testosterone, LH and FSH was reduced significantly (P < 0.05) in arsenic group, while the serum level of cortisol was increased. Vitamin E alleviated the toxic effects of arsenic on semen and hormonal parameters. It may be concluded from this study that sodium arsenite causes major toxicity changes in semen and hormonal profile in Teddy goat bucks and vitamin E has ameliorative effects on these toxic changes.     

Sperm binding to hyaluronan is an excellent predictor of Nili-Ravi buffalo bull fertility

This study reports the first evaluation of sperm hyaluronan binding assay (HBA) for predicting the fertility of Nili-Ravi buffalo bulls in relation to standard parameters of sperm quality. Cryopreserved semen doses of low (n = 6), medium (n = 3) and high fertility (n = 8) bulls based on their respective return rates were used. Significantly, more spermatozoa bound to hyaluronan from the most fertile bulls (57.15% ± 1.44) compared with medium (42.46% ± 1.08) and low fertility bulls (29.70% ± 0.78). A strongly positive correlation (r = .824, p < .01) was found between HBA and fertility that predicts a 67.9% variability (r² = .679, p < .01) in fertility. HBA was also strongly positively correlated with sperm viability (r = .679, p < .01) followed by their live/dead ratio (r = .637, p < .01), uncapacitated spermatozoa (r = .631, p < .01), normal apical ridge (r = .459, p < .01), motility (r = .434, p < .01), mature spermatozoa with low residual histones (r = .364, p < .01), high plasma membrane integrity (r = .316, p < .01) and nonfragmented DNA levels (r = .236, p < .05). It was negatively correlated with spermatozoa having reacted acrosome (r = −.654, p < .01). A fertility model built using a combination of sperm HBA and either sperm livability or viability predicts, respectively, 86.1% (r² = .861, p < .01) and 85.9% (r² = .859, p < .01) variability in buffalo bull fertility. In conclusion, sperm HBA may prove to be a single robust predictor of Nili-Ravi buffalo bull fertility.     

The changes in semen quality,arginase activity and nitric oxide level in dexamethasone-treated rams

This study was made to investigate the effects of intramuscular administrations of dexamethasone on seminal plasma nitric oxide levels and arginase activity, and some spermatological parameters in rams. Ten Akkaraman rams weighing 50–60 kg and 2 years old were used as material in this study. The study was performed during the breeding season (September–November) for rams. The semen was collected by artificial vagina at 1st, 4th, 24th, 48th, 72nd and 96th hours for control group before dexamethasone administration. For treatment group, 0.25 mg/kg dexamethasone was administered and semen was collected at the time points described for control group. Spermatological characteristics of semen samples (semen volume, pH, sperm motility, density and abnormal sperm rate), seminal plasma arginase enzyme activities and nitric oxide levels were determined. It was determined that the administration of dexamethasone was detected to decrease seminal plasma arginase activity (p < .05 and .01) and nitric oxide level (p < .05), semen volume (p < .05 and .01), mass activity (p < .05 and .01), sperm density (p < .05) and sperm motility (p < .05 and .01), and to increase abnormal sperm rate (p < .05 and .01). In conclusion, dexamethasone is not recommended to be used during the breeding season as it damages the sperm quality of the rams.     

Effects of smoking on fatty acid composition of phospholipid sperm membrane and the malondialdehyde levels in human seminal plasma

The aim of this study was to investigate fatty acids composition of sperm phospholipids, level of lipoperoxidation represented by malondialdehyde and to examine differences between recent smokers and nonsmokers. The levels of malondialdehyde were in the group of all patients 1.51 ± 0.56 μmol l^?1, in smokers 1.36 ± 0.59 μmol l^?1 and in nonsmokers 1.53 ± 0.55 μmol l^?1. Total sperm membrane phospholipid fatty acids were profiled into several groups, saturated acids (in smokers 61.86 ± 9.02%, in nonsmokers 61.20 ± 11.66%), polyunsaturated acids n‐3 (in smokers 12.62 ± 8.18%, in nonsmokers 14.28 ± 13.65%), polyunsaturated acids n‐6 (in smokers 9.13 ± 4.37%, in nonsmokers 10.10 ± 3.79%) and other acids (in smokers 14.36 ± 3.94%, in nonsmokers 13.88 ± 2.31%). Significant correlations were found between the level of malondialdehyde (MDA) and total sperm motility in all patients (r = ?0.358, P = 0.013), between both the level of MDA and progressive motility (r = ?0.465, P = 0.001) and between the level of MDA and total motility (r = ?0.382, P = 0.037) in nonsmokers. There were no statistically significant differences between composition of sperm phospholipid important fatty acids in smokers and nonsmokers. Significant correlations between selected sperm fatty acids and sperm motility and morphology in smokers and nonsmokers were not observed.     

Effect of omega-3 polyunsaturated fatty acid supplementation on semen profile and enzymatic anti-oxidant capacity of seminal plasma in infertile men with idiopathic oligoasthenoteratospermia: a double-blind, placebo-controlled, randomised study

Effective medical treatments of infertile men with idiopathic oligoasthenoteratospermia (OAT) have yet to be determined. This study considered two major aims: (i) to measure the changes in semen parameters, omega‐3 fatty acids (FA) compositions and anti‐oxidant activity; (ii) to determine if the administration of omega‐3 FA affect semen quality in infertile men with OAT. Two hundred thirty‐eight infertile men with idiopathic OAT were randomised to eicosapentaenoic (EPA) and docosahexaenoic acids (DHA), 1.84 g per day (EPAX 5500TG; Lysaker, Norway), or placebo for 32 weeks. The semen parameters were assessed according to WHO criteria, and the EPA and DHA concentrations were determined in red blood cells (RBCs), seminal plasma and sperm cells at baseline and 32‐week treatment period. Of randomised subjects, 211 (88.7%) completed the full 32‐week randomisation period. The anti‐oxidant status of seminal plasma was also evaluated by measuring the superoxide dismutase (SOD) and catalase‐like activity. In the total group of participants, all EPA and DHA levels in RBC, and seminal plasma, were statistically significantly correlated with those in spermatozoa (both P = 0.001). A significant improvement of sperm cell total count (from 38.7 ± 8.7 ′ 10⁶ to 61.7 ± 11.2 ′ 10⁶, P = 0.001) and sperm cell concentration (from 15.6 ± 4.1 ′ 10⁶ per ml to 28.7 ± 4.4 ′ 10⁶ per ml, P = 0.001) was observed in the omega‐3 group. A significant positive correlation was found between the EPA and DHA in seminal plasma and the semen parameters. Seminal plasma EPA and DHA concentrations were positively correlated with seminal plasma SOD‐like and catalase‐like activity (both P = 0.001). In seminal plasma, both SOD‐like and catalase‐like activity were positively correlated with sperm count, sperm motility, and sperm morphology. Oligoasthenoteratospermic men with low levels of EPA and DHA may benefit from omega‐3 FA supplementation. Further studies are warranted to shed more light on this important issue.     

Evaluation of the cryoprotective effect of seminal plasma on llama (Lama glama) spermatozoa

In South American camelids, sperm survival is low after thawing and poor results are obtained when artificial insemination is performed with cryopreserved semen. The aim of this study was to evaluate the effect of different percentages (10% and 50%) of seminal plasma added prior to the process of cryopreservation and also to evaluate the absence of seminal plasma on llama sperm survival after freezing and thawing. A total of 15 ejaculates from five adult llama males (n = 5; r = 3) were evaluated. A significant decrease in sperm motility, viability, membrane function and intact acrosomes was observed in thawed samples (0%, 10% and 50%) when compared to raw semen. Neither morphology nor chromatin condensation was altered in all thawed samples (p > 0.05), but a significant increase (p < 0.05) in the percentage of spermatozoa with fragmented DNA was observed after thawing all samples compared to raw semen. Higher percentages of total and progressive sperm motility were observed when 0% and 10% of seminal plasma were used compared to 50%. However, no statistical differences were established for sperm viability, membrane function, morphology, acrosome status and DNA quality between thawed treatments. To conclude, neither of the percentages of seminal plasma used showed superiority nor cryoprotective effect on llama sperm survival.     

High levels of oxidation–reduction potential in frozen-thawed human semen are significantly correlated with poor post-thaw sperm quality

This study examined the relationship between oxidation–reduction potential (ORP) in frozen-thawed semen and the post-thaw sperm parameters. Levels of ORP were measured in 25 samples from men presenting for routine infertility work-up and were expressed as millivolt (mV)/10⁶ sperm/ml. Frozen-thawed samples were examined for post-thaw total motility (TM%), progressive motility (PM%), total sperm count (TSC) and ORP. The cryo-survival rate (CSR) was calculated as post-thaw TM/pre-freeze TM × 100. Data are provided as median and interquartile range (25th and 75th percentiles). The post-thaw TM% (10.0% [4.00%, 15.1%]), PM% (5.88% [2.97%, 9.33%]) and TSC (12.5 [10.0, 17.5] × 10⁶ sperm) were significantly lower than the pre-freeze TM% (45.9% [32.9%, 59.1%], PM% (31.5% [24.4%, 40.0%] and TSC (120 [90, 250] ×10⁶ sperm) (p < .001). Post-thaw ORP (2.62 [2.52, 3.13] mV/10⁶ sperm/ml) was significantly higher than pre-freeze ORP (0.73 [0.54, 1.21] mV/10⁶ sperm/ml; p < .001). The CSR was 21.7% (11.3%, 31.9%). The post-thaw seminal ORP was negatively correlated with post-thaw TM% (r = −.5; p = .02), PM% (r = −.41; p = .03), TSC (r = −.60; p = .03) and CSR (r = −.52; p = .01). Increased levels of ORP are significantly correlated with poor post-thaw sperm quality and CSR.     

Sperm impairments in adult vesper mice (Calomys laucha) caused by in utero exposure to bisphenol A

This study aimed to evaluate the effects of in utero administration of bisphenol A (BPA) on semen parameters of vesper mice. Sixty female Calomys laucha were divided into six groups and received by gavage during gestation the following substances: Water (negative control), Olive Oil (vehicle control), Diethylstilbestrol (DES – positive control – 6.5 μg kg^?1 bw) and BPA (40, 80 and 200 μg kg^?1 bw). Male offspring were euthanised at 70 days of age, and sperm parameters were analysed. BPA reduced normal sperm morphology (water = 96.1 ± 0.65; BPA200 = 96.8 ± 2.3%), sperm membrane integrity (water = 88.8 ± 1,65; BPA200 = 70.6 ± 4,15%), sperm motility (water = 87.5 ± 1.71; BPA200 = 51.3 ±9.9%) and in vitro penetration rates (water = 55.0 ± 7.14; BPA200 = 7.47 ±2.96%), but it did not affect body weight, anogenital distance, sperm DNA integrity and acrosome integrity. In conclusion, in utero exposure to BPA caused a reduction in sperm parameters of adult C. laucha. Natural mating studies should be conducted to verify the effects of BPA on fertility of the animals.     

Heme oxygenase enzyme activity in seminal plasma of oligoasthenoteratozoospermic males with varicocele

This work aimed to assess seminal plasma heme oxygenase (HO) enzyme activity in oligoasthenoteratozoospermia (OAT) males with varicocele. Ninety‐three men were divided according to their sperm count and clinical examination into: healthy fertile controls (n = 34), OAT without varicocele (n = 37) and OAT associated with varicocele (n = 22). They were subjected to semen analysis and estimation of seminal plasma HO enzyme activity in the form of bilirubin concentration. Seminal plasma HO enzyme activity decreased significantly in OAT cases compared with controls. Seminal plasma HO in OAT cases associated with varicocele decreased significantly compared with OAT cases without varicocele and healthy controls (mean ± SD; 109.2 ± 29.5, 283.6 ± 88.4, 669.5 ± 236.1 nMol bilirubin/mg ptn/min, P < 0.001). There was positive correlation between seminal plasma HO enzyme activity and sperm concentration, per cent of motile spermatozoa, number of motile spermatozoas ml^?1 and significant negative correlation with sperm abnormal forms per cent. It is concluded that varicocele has a negative impact on seminal HO enzyme activity. Therefore, improved seminal picture after correcting varicocele repair might be related, in part, to improved HO action(s).     

Does Lepidium meyenii (Maca) improve seminal quality?

Maca (Lepidium meyenii) is a herbaceous plant grown at over 4,000 m in Peru. It has been studied worldwide for its properties on fertility. Previous studies have assessed maca effects on semen quality, but there is need of randomised, double-blind trials in order to make clinical decisions. The objective of this study was to assess the effect of maca on seminal parameters in infertile adult men. This is a double-blind, randomised, placebo-controlled pilot trial in which sixty-nine patients diagnosed with mild asthenozoospermia and/or mild oligozoospermia were supplied by maca (n = 35) or placebo (n = 34) (2 g/day) for a period of 12 weeks. When compared patients treated with maca and patients treated with placebo, there were no significant differences in semen volume (2.95 ± 0.52 vs. 2.90 ± 0.52; p = .392), sperm motility (22.34 ± 2.22 vs. 23.05 ± 2.22; p = .462) and normal sperm morphology (7.89 ± 1.89 vs. 7.04 ± 2.28; p = .801), but there was a significant difference in sperm concentration (15.04 ± 5.61 vs. 10.16 ± 3.59, respectively; p = .011). In conclusion, patients treated with 2 g of maca for a period of 12 weeks showed a significant improvement in seminal concentration compared with patients treated with placebo. There were no significant differences in semen volume, sperm mobility and morphology when compared both groups.     

DNA hydroxymethylation rate in the AChE and HoxC4 promoter associated with human sperm quality

The relationship of altered DNA 5′‐hydroxymethylation in human spermatozoa with seminal parameters remains unclear. The aim of the study was to investigate the association between the 5′‐hydroxymethylcytosine (5hmC) rate in the promoters of acetylcholinesterase (AChE) and homeobox C4 (HoxC4) genes and human sperm concentration/motility. The study population consisted of three groups: asthenozoospermia (AZ), oligoasthenozoospermia (OAZ) and normozoospermia (NZ). The 5hmC rate in the promoter was measured by CCGG loci‐dependent MspI/HpaII restriction mapping of glycosylation‐modified sperm DNA combined with a hydroxymethylation‐specific real‐time polymerase chain reaction assay. The 5hmC rate in the AChE promoter in group AZ and OAZ was higher than that in group NZ (p < .05). A weak inverse correlation between 5hmC rate of AChE and sperm motility was observed in all subjects (r = ?.172, p < .05). The 5hmC rate in the HoxC4 promoter in group OAZ was lower than that in group NZ (p < .05). These results indicated that altered 5hmC rates of AChE and HoxC4 promoters are associated with low sperm motility and sperm concentration respectively.     

Incubation of frozen-thawed llama sperm with seminal plasma

Seminal plasma is intimately connected to sperm physiology and particularly in South American Camelids, has demonstrated to be involved in multiple physiological reproductive events. Different percentages of seminal plasma (0%, 10% and 50%) were added to thawed llama semen samples with the objective of evaluating the interaction with cryopreserved sperm over time (0, 1.5 and 3 hr at 37°C). A total of 20 ejaculates from five adult llama males (n = 5; r = 4) were evaluated. A significant decrease in sperm motility, membrane function and live sperm was observed in all thawed samples (0%, 10% and 50%) at 0 hr when compared to raw semen. Neither morphology nor chromatin condensation was altered in all thawed samples (p > .05), but a significant increase in the percentage of spermatozoa with fragmented DNA was observed after thawing all samples versus raw semen. When evaluating thawed samples over time, a significant decrease of motility and membrane function was observed, while the percentages of total live sperm were preserved over the 3 hr of incubation in all final concentrations evaluated. To conclude, the addition of 10% or 50% of seminal plasma was incapable of preserving motility or membrane function of frozen-thawed llama sperm during 3 hr of incubation.     

Cumene hydroperoxide induced changes in oxidation–reduction potential in fresh and frozen seminal ejaculates

Oxidation–reduction potential (ORP) is a newer integrated measure of the balance between total oxidants (reactive oxygen species—ROS) and reductants (antioxidants) that reflects oxidative stress in a biological system. This study measures ORP and evaluates the effect of exogenous induction of oxidative stress by cumene hydroperoxide (CH) on ORP in fresh and frozen semen using the MiOXSYS Analyzer. Semen samples from healthy donors (n = 20) were collected and evaluated for sperm parameters. All samples were then flash‐frozen at ?80°C. Oxidative stress was induced by CH (5 and 50 μmoles/ml). Static ORP (sORP—(mV/10⁶ sperm/ml) and capacity ORP (cORP—μC/10⁶ sperm/ml) were measured in all samples before and after freezing. All values are reported as mean ± SEM. Both 5 and 50 μmoles/ml of CH resulted in a significant decline in per cent motility compared to control in pre‐freeze semen samples. The increase in both pre‐freeze and post‐thaw semen samples for sORP was higher in the controls than with 50 μmoles/ml of CH. The change from pre‐freeze to post‐thaw cORP was comparable. The system is a simple, sensitive and portable tool to measure the seminal ORP and its dynamic impact on sperm parameters in both fresh and frozen semen specimens.