Percentage Of Viable Spermatozoa Research Articles

Effect of modifiable risk factors on semen parameters

Objective: This article examines the potential effects of lifestyle factors on male reproductive health. Evidence of a global decline in human sperm quality over recent decades has been accumulating. Environmental, occupational and modifiable lifestyle factors may contribute to this decline. This review focuses on key lifestyles factors such as diet, caffeine intake, tobacco chewing and alcohol intake. Method: A comprehensive literature search was performed to identify the major lifestyle factors associated with male infertility and semen quality. Database searches were limited to reports published in English only. Results: A prudent diet consists of high intake of fish, fruit, vegetables and legumes. Fat in diet is also as essential as other component of the diet. Although largely the evidence is observation based, evidence appears to support an approach of moderation carbohydrate and fats with better semen parameters. A good intake of antioxidants in diet and supplement correlates with higher sperm numbers and motility. The other very important modifiable factors are tobacco chewing, alcohol and caffeine intake. Nicotine in tobacco is found to suppress sperm progressive motility; it also reduces the percentage of viable spermatozoa and increases the altered chromatin compactness. Alcohol consumption leads to increased testosterone level due to change in oxidation metabolism of steroids in liver. Alcohol oxidation increases the Nicotinamide adenine dinucleotide (NAD) ratio which causes the re-dox state in favour of conversion of androstenedione into the reduced steroids testosterone and oestradiol. Caffeine intake has been associated with sperm DNA defects, aneuploidy and DNA breaks. Conclusion: The major lifestyle factors discussed in the present review are the potential issues that can possibly impair male infertility. However, their negative impact can be overcome by behavioural modification and better lifestyle changes.

Impact of selenium nano-particles in semen extender on bull sperm quality after cryopreservation

The aim of this study was to evaluate the effect of adding different concentrations of selenium nano-particles (Se-NPs) in semen extender on bull sperm cryopreservation. Five healthy, fertile Friesian bulls were used, and the ejaculates were obtained using an artificial vagina. Semen of all bulls were pooled and diluted in a tris-yolk fructose (TYF) extender supplemented with Se-NPs at concentrations of 0 (T1, control), 0.5 (T2), 1.0 (T3) and 1.5 (T4) μg/ml for a final sperm concentration of 80 × 106 sperm cells/ml. Diluted semen was packed in straws (0.25 ml) and stored in liquid nitrogen (−196 °C) for one month. After thawing, semen of each treatment was evaluated for sperm quality parameters, including sperm progressive motility, livability, morphological abnormalities, plasma membrane integrity and chromatin integrity. Apoptosis and sperm ultrastructure were also examined. Total antioxidant capacity and lipid peroxidation markers were determined in seminal plasma of semen in each treatment. Finally, the effect of Se-NPs on fertilization capacity was checked in vivo using n = 81cows. Results showed that T2 and T3 had a positive effect (P < 0.05) on post-thawing sperm progressive motility, livability and membrane integrity as compared with the control. Percentage of viable sperm increased (P < 0.05), while percentages of early apoptotic, apoptotic and necrotic sperm cells decreased (P < 0.05) in T3 as compared to T1. Total antioxidants capacity (TAC) in seminal plasma increased (P < 0.05) and malondialdhyde (MDA) concentration decreased (P < 0.01) in T3 as compared to T1, but did not differ in T4 from that in T1. In vivo fertility rate was higher in T3 (90%) than in T1 (59%).In conclusion, enrichment of semen extender with Se-NPs at a concentration of 1.0 μg/ml improved post-thaw sperm quality of Holstein bulls, and consequently in vivo fertility rate by reducing apoptosis, lipid peroxidation and sperm damage occurring by cryopreservation.

Investigating the factors affecting the outcomes of the sperm sorting with microfluidic devices

The problem of infertility in animals caused by the abnormality and deficiency of sperms can be solved by Assisted Reproductive Technology (ART). However, the methods of ART require a high quality of sperms to enhance the fertilization rate. In this paper, we focused on investigating the factors that affect the quality of sperms, which were sorted by the simple design of microfluidic devices (MFD). The first factor was associated with the types of polymer, which is used for fabrication. The second factor was related to the distance that sperms swam. The last factor was the temperature that we used for incubating sperms. The results showed that the PDMS MFD was more effective than the SU-8 MFD, and the most suitable distance that the frozen–thawed bull sperms could swim with having less effect of sperm exhaustion was 5 mm. More importantly, we are the first to prove that incubating sperms in the MFD at 37 °C was unnecessary. The percentage of sperm viability for the room temperature (25 °C) was significantly higher than incubation at 37 °C. For this reason, it could be concluded that incubating sperms at 25 °C could be sufficient. This makes it possible to reduce the time consumption and cost of sorting sperms with the MFD as we can eliminate the incubating process and equipment. Moreover, we further assessed the quality of the sperms, which were sorted with PDMS MFD at the channel length 5 mm compared with the pre-sorted sperms. The results revealed that the percentage of progressive motile sperms significantly increased, while the percentage of abnormality significantly reduced. Based on these results, it could be concluded that sorting sperm with a PDMS MFD has a less negative effect on the quality of the sperms.

THE DIFFERENT EFFECTS OF ZINC SUPPLEMENT AND VELVET BEAN MUCUNA PRURIENS EXTRACTS TOWARD FERTILITY OF BALBC/ MICE

Abstract: Good quality velvet beans and zinc supplement are well studied and known as rich source ofaphrodisiac. The following reseach was carried out to study the difference effect of zinc supplement (ZS)and velvet bean extracts (VBE) towards fertility of BALB/c mice i.e the number of sperm, the motility ofsperm, the viability of sperm, the morphology of sperm, the existence of vagina plug, and the birthcondition of mice. This study was an experiment using Posttest Only Controlled Group Design with threegroups. The first group (A1) as control, the second group (A2) receives subcutaneous injection of 2-methoxyethanol fraction as much as 200 mg/kg weight/day for 5 days, followed with ZS at a dosage of0,026 mg/day/head, and the third group (A3) receives subcutaneous injection of 2-methoxyethanolfraction as much as 200 mg/kg weight/day for 5 days, followed with VBE at a dosage of 56 mg/kg weight/day for 30 days. The quality of spermatozoa of A1, A2, and A3 was significant difference (p &lt; 0.05).Both of A2 and A3 were no significant difference of mean number of sperm (p = 0.274), mean percentageof sperm motility (p = 0.739), mean percentage of sperm viability (p = 0.141) and mean value ofmorphology of sperm (p = 0.394). The quality of spermatozoa and the total number of baby mice livedand died of A1, A2 and A3 were significant difference. In addition, there was no significant differencein the existence of female mice's vaginal plug of A1, A2 and A3. This study showed that ZS and VBE canincrease the quality of spermatozoa of BALB/C mice.

Effects of chlorogenic acid and caffeic acid on the quality of frozen-thawed boar sperm.

Chlorogenic acid (CGA) and caffeic acid (CA) are potent antioxidants that are mostly found in coffee beans. This study aimed to investigate the effects of CGA and CA supplementation during semen freezing on the quality of frozen-thawed boar spermatozoa. The antioxidants CGA and CA were added to a semen extender to achieve final concentrations of 50, 100, 200 and 400µM. Supplementation of 100µM CGA and CA yielded a significantly higher percentage of sperm viability (increased by 8%-10%) and plasma membrane integrity (increased by 4%-6%) than the control groups without the antioxidants at 0 and 3hr after thawing (p<0.05). At a concentration of 100µM, CGA and CA also yielded beneficial effects on total and progressive sperm motility. Increases of CGA and CA concentrations to more than 200µM did not enhance any sperm quality parameters. When the sperm penetrability and oocyte development by spermatozoa frozen with CGA and CA were evaluated, CGA and CA supplementations had no positive effects on the percentages of total fertilization, monospermic fertilization, cleavage and blastocyst formation. In conclusion, the supplementation of 100µM CGA and CA during sperm freezing improved certain sperm parameters including motility, viability and plasma membrane integrity.

Effects of folic acid on testicular toxicity induced by bisphenol-A in male Wistar rats

ABSTRACTWe investigated the protective effect of the folic acid (FA) against bisphenol-A (BPA) induced toxicity in rat testis. We used four groups of seven adult male Wistar albino rats. The control group was fed corn oil, the BPA group was given BPA, the FA group was given FA and the FA + BPA group was given FA initially followed by BPA 1 h later. The BPA, FA and corn oil were administered by oral gavage for 14 days. At the end of the experiment, testis sections were examined for histological and histomorphometric characteristics. The TUNEL method was used to detect apoptosis and immunohistochemistry was used to examine the distribution of spermatogonial stem cells. Levels of serum testosterone were measured, and sperm viability and morphology were determined. The histological structure of the testis was normal in the control and FA groups. Although the number of TUNEL positive cells/tubule increased, the seminiferous epithelium height (SEH) at stages VII−VIII decreased in the BPA group compared to the control, FA and FA + BPA groups. The number of TUNEL positive cells/tubule decreased and the SEH at stages VII−VIII increased in the FA + BPA group compared to the BPA group. No significant difference in spermatogonial stem cells was found among groups. The level of serum testosterone and percentage of viable sperm was significantly lower, while the head, midpiece and total sperm abnormalities were significantly higher in the BPA treated group compared to control, FA, FA + BPA groups. It appears that the toxic effects of BPA on testis might be minimized by FA treatment.

Resveratrol significantly improves the fertilisation capacity of bovine sex-sorted semen by inhibiting apoptosis and lipid peroxidation

The aim of this study was to test the effects of five different concentrations (0, 10−3, 10−4, 10−5, and 10−6 M) of resveratrol (Res) supplementation in bull sperm washing and fertilisation medium on levels of reactive oxygen species (ROS), phosphatidylserine (PS) externalisation, mitochondrial membrane potential (Δψm), ATP and malondialdehyde (MDA), acrosomal integrity, blastocyst rate, and blastocyst quality after in vitro fertilisation (IVF). The results for sex-sorted sperm from three bulls showed: (1) ROS and MDA levels in 10−3 M and 10−4 M Res groups were significantly lower than those of controls (P < 0.05); (2) the percentage of viable sperm, percentage of sperm with high Δψm, and the ATP content in 10−3 M and 10−4 M Res groups were significantly higher than those of controls (P < 0.05); (3) the percentage of viable sperm with acrosomal integrity, and the blastocyst percentage and quality of the 10−4 M Res group were significantly higher than those of controls (P < 0.05). In conclusion, 10−4 M Res supplementation in washing and fertilisation medium of sex-sorted bull sperm significantly decreased ROS, PS externalisation, and MDA, and protected mitochondrial function and acrosomal integrity, thereby increasing blastocyst percentage and quality following IVF.

Improving Sperm Viability After Spinal Cord Injury Using Hyperbaric Therapy

Infertility is one of many complications of spinal cord injury (SCI) in male patients, who are often at the peak of their reproductive life. This study evaluated effects of hyperbaric therapy (HT) on quality of sperm of rats with SCI and correlated the findings with histologic analysis of the testicles. This experimental study comprised 18 rats that were submitted to SCI with a MASCIS Impactor and randomly allocated to either a HT or a control group. Testicular biopsies were performed on the first and 28th day of the study; 4 parameters were evaluated: concentration of sperm per mL, number of round cells per field, number of inflammatory cells per field (peroxidase [Endtz] test), and sperm viability (hypo-osmotic swelling test). There was no difference in sperm concentration between the HT group (P= 0.41) and control group (P= 0.74) during 28 days. From day 1 to day 28, sperm viability decreased twice as much in the control group (P= 0.001) compared with the HT group (P= 0.017). There was no difference between the groups in mean sperm concentration and number of round and inflammatory cells. On the first day, there was no difference in sperm viability between groups. There was a significantly higher (P=0.001) percentage of viable sperm in the HT group (86.8 ± 5.6) compared with the control group (48.8 ± 21.8) on day28. SCI increased the number of round and inflammatory cells and diminished sperm viability in both groups. HT promoted greater sperm viability in rats with SCI.

Evaluación comparativa de dos métodos de recuperación espermática de epidídimos bovinos post-mortem

Determine the appropriate method to recover bovine’s epididymal sperm in different post-mortem recovery times was the objective of the current studies. Testicles from 50 bulls of different breeds and ages, sanitary status, were obtained after the sacrifice of it in the slaughterhouse located in Loja city, Ecuador; testing two methods of seminal collection: retrograde wash and slicing. The testicles/epididymal were transported in 0.9% sodium chloride solution and storaged during 2, 4, 8, 12 and 24 hours at 5oC, to test spermatic quality in relation with passed time from its sacrifice, to the sperm collection in the laboratory. The evaluated parameters were: mass motility, individual motility, percentage of viable sperm, and normal. In the analysis of the results descriptive statistics were used and for the variance analysis Tukey test were used to determine the statistical differences between averages. The epididymal spermatozoa showed: mass motility 60.4% ± 4.75; Individual motility 50.7% ± 4.75; Vitality 60.6% ± 3.85; Abnormalities 8.78% ± 1.4; there is no significant difference (p>0.05) between protocols, getting average volumes of 2.2±05 ml, concentration of 63.08% ± 2.05, the percentage of living sperm was more when the method of retrograde wash was used. It is concluded that is possible collect living sperm from the post-mortem epididymis bull’s tail, being its vitality directly proportional to the storage time. Key words: Epididymal, spermatic quality, retrograde washing, slicing.

The Effect of Density Gradient Centrifugation and Magnetic-Activated Cell Sorting with the Combination of Both on Bovine Spermatozoa Kinematics, Viability and Acrosome Status

Conventional and novel spermatozoa separation techniques have their own strength and weaknesses. Both are widely used in assisted reproductive technologies (ARTs). In this study, combinations of two separation methods against single separation methods were evaluated. Freshly ejaculated semen was collected and divided into five groups; control, density gradient centrifugation (DGC), magnetic activated cell sorting (MACS), DGC-MACS and MACS-DGC; based on the sequence of separation. Evaluation of spermatozoa kinematics, viability and acrosome status for each group were done by computer assisted semen analysis (CASA), hypo-osmotic swelling test (HOST) and chlorotetracycline (CTC) staining respectively. Results show that DGC yield the fastest spermatozoa velocity and highest percentage of viable spermatozoa fraction compared to other groups. However, they also produced a high percentage of acrosome-reacted spermatozoa. Spermatozoa isolated through DGC-MACS shows the highest percentage of non-capacitated spermatozoa. However, spermatozoa isolated through DGC-MACS yields slower spermatozoa velocity population and lower percentage of viable sperm compared to spermatozoa isolated through DGC. Isolation of spermatozoa through MACS-DGC yields slower population of spermatozoa velocity with a lower percentage of non-capacitated spermatozoa compared to spermatozoa isolated through DGC-MACS. DGC separation and its combination with MACS had yield different spermatozoa quality. This distinct characteristic is likely suitable for in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) procedure respectively.

Effect of Amifostine on Sperm DNA Fragmentation and Testes after Radioiodine Treatment.

IntroductionRadioactive iodine (RAI) is commonly used for the treatment of hyperthyroidism caused by Graves’ disease or thyroid nodules. However, information available on the impact of RAI therapy on male gonadal function is scarce. This study aimed to determine any possible damage to testicular tissue and sperm quality caused by RAI therapy, and the radioprotective effect of amifostine against such damage.Material and MethodsIn total, 36 rats were randomly allocated to three groups, including a control group, RAI group (111 MBq Iodine-131), and RAI + amifostine group (111 MBq Iodine-131 and a single dose of 200 mg/kg amifostine). Blood and epididymal sperm samples were taken for hormone analyses and the evaluation of spermatological parameters. The TUNEL assay and haematoxylin-eosin were used to stain testicular tissue samples to detect histological changes and apoptosis.ResultsThe groups differed insignificantly for the testicular mass index and spermatozoa concentration. However, spermatozoa motility and percentage of viable spermatozoa were higher in the RAI + amifostine group, compared to the RAI group. Sperm DNA fragmentation and the index of apoptotic germ cells significantly decreased in the amifostine group, in comparison to the radioiodine group. While the testosterone levels showed no significant change, the follicle stimulating hormone (FSH) levels significantly decreased in the RAI + amifostine group.ConclusionAll histopathological parameters and some spermatological parameters showed that RAI therapy caused statistically significant damage of testicular tissue and this damage was reduced by amifostine.

In vivo evidences of Curcuma longa on oxidative stress in STZ-induced diabetes on sperm parameters in male wistar rats

Several conditions such as chemotherapy and toxins can interfere with spermatogenesis and reduce sperm quality and production. In the case where natural antioxidant response cannot manage oxidative stress and free radical overload, oxidative damage occurs and this begins the genesis of many diseases of which diabetes is one of them. This has awakened the interest of researchers to the use of an alternative source of medicine and herbal medicine. Medicinal use of Curcuma longa dates back to ancient China and India; its constituents are stated to have anti-hepatotoxic, anti-inflammatory, stimulant, and antioxidant and used since ancient time as medicinal and nutritive origins knowing to possess androgenic activities and have well effect in diseases treatment in more countries world-wide. As an antioxidant Curcuma longa possible has a useful effect on spermatogenesis and sperm parameters. Wistar male rats (n=24) were allocated into six groups, positive control (n=4), diabetic control (n=4) and experimental groups (n=20), that subdivided into groups of 4 that received treatment of Curcuma longa rhizome powder with or without STZ-induced diabetes in the dosages (25 and 100mg/kg/day) for 21 consecutive days. In twenty-second day, the testes were removed and semen was collected from epididymis and prepared for analysis. The percentage of sperm viability and motility in the treatment groups increased mildly with a significance of: (p&lt;0.05) in comparison to control group and with the diabetic group being critically lower than those in control group. This suggested that Curcuma longa may be promising in enhancing sperm health parameters.Keywords: Turmeric, oxidative stress, semen, STZ-induced diabetes, antioxidant

Effects of supplementation of the Tris-egg yolk extender with n-3 polyunsaturated fatty acids (PUFAs) on frozen-thawed ram semen characteristics

The present study was conducted to evaluate the effects of supplementation of Tris-egg yolk extender with the different concentrations of n-3 PUFAs (DHA+EPA) on the freezability of ram semen. Semen samples were collected from five fertile rams using an artificial vagina, once a week, for 8 weeks in July and September. The selected ejaculates were extended and pooled into Tris-egg yolk extender supplemented with 0 (control), 10, 30 and 50ngml−1 concentrations of n-3 PUFAs. The extended samples were cooled for 3h at 4°C and packed in 0.5ml straws, frozen in liquid nitrogen for a week. The mean percentage of sperm motility in 50ngml−1 (35.6±1.8%) and 30ngml−1 (37.5±1.8%) n-3 FAs supplemented groups was significantly lower than that of control group (43.1±1.8%; P<0.01). The mean percentage of sperm viability in 30ngml−1 (38.9±1.5%) and 50ngml−1 (36.4±1.5%) n-3 FAs supplemented groups was significantly lower than that of control group (43.8±1.5%; P<0.01). The plasma membrane integrity was significantly lower in 50ngml−1 n-3 FAs supplemented group (29.6±1.6%) than that of control group (34.2±1.6%; P<0.05). The mean percentage of sperm tail defects was also significantly higher in group containing the n-3 FAs of 50ngml−1 (P<0.05). In addition, post-thaw sperm motility (P<0.05), viability (P<0.001) and plasma membrane integrity (P<0.05) in n-3 FAs supplemented groups decreased more significantly in September than those in July. In conclusion, the addition of n-3 PUFAs in Tris-egg yolk extender did not improve the freezability of ram semen and had more detrimental effects on sperm cell after freezing-thawing in the breeding season.

Freezability genetics in rabbit semen

The aim of this study was to estimate the heritability of semen freezability and to estimate the genetic correlation between frozen-thawed sperm traits and the growth rate in a paternal rabbit line. Estimated heritabilities showed that frozen-thawed semen traits are heritable (ranged between 0.08 and 0.15). In the case of Live-FT (percentage of viable sperm after freezing), the estimated heritability is the highest one, and suggests the possibility of effective selection. After the study of genetic correlations it seems that daily weight gain (DG) was negatively correlated with sperm freezability, but no further conclusions could be drawn due to the high HPD95%. More data should be included in order to obtain better accuracy for the estimates of these genetic correlations. If the results obtained at present study were confirmed, it would imply that selection for DG could alter sperm cell membranes or seminal plasma composition, both components related to sperm cryoresistance.

Effect of Sappan Wood Ethanol Extracts (Caesalpinia sappan. L) to the Sperm Motility, Viability, and Concentration of Male Wistar Rats

Background: Idiopathic male infertility becomes an issue because of the limited management options and increasing number of infertile couples. Sappan wood ( Caesalpinia sappan. L ) is an herbal plant predicted to have fertility and spermatogenesis enhancing effects through antioxidant properties. This study aimed to observe the effects of sappan wood ethanol extract in improving sperm quality of male wistar rat based on sperm motility, viability, and concentration. Methods: This was an experimental laboratory study by using sappan wood ethanol extracts as material and male wistar rat as the experimental animal. Twenty-four adult male wistar rats were divided into 4 groups including rats which were treated with aquades, 30, 60, and 120 mg/kg/day/orally of ethanol extract of sappan wood, respectively, during 35 days. After this period, the animals were sacrificed. Then the epididymis were taken for samples to calculate sperm motility percentage, sperm viability percentage and sperm concentration. Comparison between control group and the treated group was analyzed by one-way Annova. Results: There were significant differences between the control group and the group with 120 mg/kg of sappan wood ethanol extracts in the percentage of motility (36.39% and 51.75%; p-value 0.001), viability percentage (55.36% and 66.63%, p-value 0.031), and sperm concentration (54.47 million/ml and 47.79 million/ml; p-value 0.001). Conclusions: The ethanol extract of sappan wood with a dose of 120 mg/kg for 35 days is able to improve sperm motility percentage, sperm viability percentage, and sperm concentration of male wistar rat. DOI: 10.15850/amj.v4n2.1078

Fertility of cold-stored mouse sperm is recovered by promoting acrosome reaction and hyperactivation after cholesterol efflux by methyl-beta-cyclodextrin.

Cold storage of the cauda epididymis, a male reproductive organ, is an efficient means of transporting genetically modified mice, an alternative to live animal shipment. The fertility of cold-stored sperm decreases in a time-dependent manner. However, the cause of the reduction in the fertility of sperm after cold storage remains unclear. It is known that cholesterol efflux from the sperm membrane is a trigger of capacitation. The dysfunction of cholesterol efflux due to changes in the membrane state in low temperatures may explain the reduced fertility. In this study, we examined the fertility (fertilization rate, acrosome reaction, and motility) and the amount of cholesterol and membrane fluidity in cold-stored sperm after treatment with two cholesterol acceptors, bovine serum albumin (BSA), and methyl-beta-cyclodextrin (MBCD). MBCD-treated sperm exhibited the highest rate of fertilization. Two-cell embryos derived from in vitro fertilization using 0.75-mM-MBCD-treated sperm after cold storage for 72 h developed to offspring. MBCD also displayed greater ability to remove cholesterol from the sperm membrane than BSA. The percentage of viable sperm with membrane destabilization was increased by MBCD in cold-stored sperm. The acrosome reaction strongly occurred in MBCD-treated sperm. In motility analysis, MBCD improved the lateral amplitude of head movement and beat frequency. These results suggest that MBCD-induced cholesterol efflux enhances membrane fluidity and promotes acrosome reaction and hyperactivation, resulting in improved fertility of cold-stored sperm.

The Effect of L-Carnitine, Hypotaurine, and Taurine Supplementation on the Quality of Cryopreserved Chicken Semen.

The objective of this study was to investigate the effect of L-carnitine (LC), hypotaurine (HT), and taurine (T) on the quality of frozen-thawed chicken semen. Pooled semen samples were divided into seven aliquots (control, 1 mM LC, 5 mM LC, 1 mM HT, 10 mM HT, 1 mM T, and 10 mM T) and subjected to cryopreservation. Postthaw sperm motility was determined by IVOS system and sperm characteristics were assessed with fluorochromes and flow cytometry. The highest sperm motility and the highest percentage of viable sperm were in the HT1 group (P < 0.01 and P < 0.05) following cryopreservation. After thawing, we observed a higher percentage of sperm without apoptosis and membrane reorganization changes in the LC1 and T1 group when compared to the control (P < 0.05). There was a higher percentage of live sperm without lipid peroxidation (LPO) in all treatments (P < 0.01; P < 0.05), when compared to the control group. The percentage of sperm with high mitochondrial potential significantly increased with LC1, T1, and T10 (P < 0.05). Supplementation of the diluent with LC1, LC5, and T1 significantly (P < 0.05) reduced DNA susceptibility to fragmentation, compared to the control and HT1 groups. These results indicate that the addition of examined antioxidants improves the quality of cryopreserved chicken semen.

Preservation of honey bee spermatozoa using egg yolk and soybean lecithin-based semen extenders and a modified cryopreservation protocol

Better protocols and suitable extenders for semen handling and cryopreservation are required for honey bees to enhance sperm quality and fertility similar to that of other species. The purpose of the present research is the improvement of honey bee sperm quality using different semen extenders and a modified cryopreservation protocol. Three different extenders were used: (1) buffer and egg yolk (EY); (2) buffer and 0.5% soybean lecithin (SL0.5); and (3) buffer and 2% soybean lecithin (SL2). Semen was collected and then diluted with the experimental extenders. The diluted semen was gradually cooled in a refrigerator to 5 °C and immediately loaded into straws and frozen with liquid nitrogen. Motility and viability data analyzed using the GENMOD and GLM procedure of SAS software. The results demonstrate that the mean fresh sperm motility in EY (4.75 ± 0.14) and SL2 (4.5 ± 0.2) were significantly (p < 0.05) higher than the SL0.5 (4.12 ± 0.12). Also, the mean of cooled motile spermatozoa in EY and SL2 were significantly higher than the SL0.5 (3.87 ± 0.24). Post-thawed sperm motility in EY (3.6 ± 0.24) was significantly (p < 0.05) higher than the other extenders. Furthermore, percentage of viable spermatozoa in EY (69.75 ± 2.32%) was significantly higher than SL0.5 and SL2 (38.5 ± 2.32 and 45 ± 2.32% respectively. Therefore, according to the results of this study, use of an egg yolk-based extender could better maintain honey bee semen motility and viability after freeze-thawing process, compared to SL-based extenders. However, more advanced tests and fertility evaluation are needed to reveal the exact effects of egg yolk and lecithin based semen extenders on post-thawed drone sperm quality.

Chicken egg yolk plasma in tris-citric acid extender improves the quality and fertility of cryopreserved water buffalo (Bubalus bubalis) spermatozoa

This study was primarily designed to evaluate the effect of different concentrations of ultraviolet (UV)-C–irradiated chicken egg yolk plasma (EYP; v:v; 10%, P1; 15%, P2; 20%, P3) or 20% (v:v) of whole chicken egg yolk (WCEY) in tris-citric acid (TCA) extender on water buffalo sperm quality during cryopreservation (postdilution, PD; postequilibration, PE; post-thawing, PT). Also the effect of best evolved concentration of UV-C–irradiated EYP in extender on in vivo fertility of buffalo spermatozoa was evaluated. At PE and PT, computer-assisted sperm analysis progressive motility (PM, %) was significantly higher in P3 compared with P1 and WCEY. Rapid velocity (RV, %) was higher (P < 0.05) in P3 compared with P1 and WCEY during cryopreservation (PD, PE, and PT). Average path velocity (μm/s) and straight line velocity (μm/s) were higher (P < 0.05) in P2 and P3 than WCEY at PE and PT. The decline percentage (%, longevity) in PM and RV was lower (P < 0.05) in P3 compared with WCEY during 2 hours incubation under in vitro condition at PT. Supravital plasma membrane integrity (%) was higher (P < 0.05) in P2 and P3 compared with control at different stages (PE and PT). Mitochondrial transmembrane potential (%) was higher (P < 0.05) in P2 and P3 compared with P1 and WCEY at different stages (PD and PT). Percentage of viable sperm with intact acrosome, and sperm DNA integrity (%) were higher (P < 0.05) in P2 and P3 compared with WCEY at PT. The in vivo fertility rate (%) was significantly higher with P3 compared with WCEY (76.61 vs. 64.49). In conclusion, WCEY (20%) can be replaced with UV-C–irradiated chicken EYP (20%) in TCA extender for cryopreservation of water buffalo spermatozoa.

Mitigation of sperm tail abnormalities using demembranation approach in the clouded leopard (Neofelis nebulosa).

Clouded leopards (Neofelis nebulosa) produced high proportion of abnormal spermatozoa (mainly tail defects) that can limit sperm movement and conception. The study aimed to better identify the origin of those defects using a demembranation approach. Ejaculates (1-2 ejaculations/male; n=9) were allocated to simple washing (control; resulting in 11.7%±1.9% coiled tails) and processed through colloid centrifugation to reduce the number of sperm with tail defects (treatment, resulting in 5.9%±0.9% coiled tails). Aliquots of semen were incubated in hypo-osmotic solution (HOS, 60 mOsm fructose solution) containing 5mM dithiothreitol (DTT) (a reducing agent) to prevent oxidation of sperm membrane. Thereafter, 20% Triton X-100 (TX) (a detergent) was added to the HOS/DTT-treated samples. After HOS/DTT incubation, the control samples and sperm-selected samples presented 73.4%±3.1% and 73.9%±2.5% swollen sperm (bent and coiled) indicating membrane intact, respectively. Most of the coiled tail in the raw ejaculates could not be opened by TX indicating that the cause of coiled sperm tails may be from testicular origin. The proportion of sperm with tightly coiled tail tended to be lower in the sperm-selected group than control group (18.8%±3.8% and 26.5%±3.4%; p=.1), whereas the sperm opened up by TX tended to be higher in the sperm-selected group (53.6%±10.4% and 21.1%±7.9%; p=.06). The results indicated TX was able to uncoil half of the tightly coiled sperm in the semen undergone preparation. In conclusion, the coiled sperm in the clouded leopard semen were likely not a defect of sperm volume regulation during post-ejaculate (osmotic swelling) but pre-ejaculate origin. Semen preparation demonstrated its ability to lessen the primary sperm defects and selected spermatozoa that were prone to be mitigated after demembranation.