Higher Sperm Viability Research Articles

Comparison between open and closed systems for vitrification of individual sperm: assessing morphometric measurements and chromatin integrity

BackgroundClassic vitrification methods are not appropriate when there are minimal numbers of viable sperm, and the new methods emphasize the low semen volumes in these cases. The aim was to assess the efficacy of the cryotech as a device for freezing low sperm volume, through the two methods of open (OVS) and closed (CVS) vitrification systems.MethodsTesticular biopsy samples from 30 men with obstructive azoospermia (OA) were assigned to three groups fresh control (FC), OVS, and CVS. Testicular sperms were selected using an ICSI injection pipette and vitrified on the cryotech straws, containing one droplet of freezing medium. After warming, sperm head morphometric characterizations were evaluated with the MSOME technique. Sperm motility, membrane integrity, chromatin quality assessment including DNA fragmentation, Chromomycine A3 staining (CMA3), and Aniline Blue (AB) were assessed. Fluorescein isothiocyanate-conjugated Pisum sativum agglutinin (FITC-PSA) was done to examine sperm acrosome integrity.ResultsThe mean sperm motility, viability, and sperm with intact acrosome reduced after vitrification, in both methods of CVS, and OVS, but the results were more promising in the closed method (p < 0.05). However, the variations were not significant between the two methods of cryopreservation, the OVS undergoes significant head dimensions changes compared to the control group (p < 0.05). The results also showed higher membrane, and chromatin abnormality after OVS (p < 0.05).ConclusionsThe overall post-thaw recovery of human testicular sperm proposes that CVS is more efficient for single sperm cryopreservation, while higher sperm viability, and lower alterations in chromatin, acrosome, and sperm head morphometry were seen compared to OVS.

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.

Sperm quality of Bali bull following sexing and freezing using different cryoprotectants

The objective of this experiment was to assess the impact of sperm sexing duration on sperm quality and to compare the effectiveness of glycerol (GC) and ethylene glycol (EG) as cryoprotectants to preserve the quality of sexed sperm during the freezing and storage in liquid nitrogen. The treatments consisted of three different durations of sexing: 40 min.(D-40), 50 min (D-50), 60 min. (D-60). The variable measured was the motility and viability of sperm following sexing and post-thawing motility of Bali bull sexed sperm cryopreserved in GC and EG. The results showed that sperm motility after sexing was significantly higher in the treatment of 40 and 50 min. compared to 60 min. of sexing duration. While the viability of sexed sperm in all treatments was not significantly different. Post-thawing motility of frozen sexed sperm cryopreserved with GS was higher than sexed sperm cryopreserved with EG. Finally, it was concluded that sexing times of 40 and 50 min. were the best time to get high sperm motility and viability of Bali bull compared to sexing times of 60 min. In addition, GS could maintain the motility of sexed sperm better than EG.

Protective Effect of Temulawak (Curcuma xanthorriza) Rhizome Extract on Monosodium Glutamate-Induced Mice Sperm

The present study aimed to determine the effect of the aqueous extract of temulawak (Curcuma xanthorriza) rhizome on the sperm quality of monosodium glutamate (MSG)-induced mice. This study used 30 male mice (aged 2.5-3 months old and weighing 25-30 g), which were then randomly divided into 5 groups: K- (healthy male mice received only aquadest), K+ (male mice exposed to 4 mg/kg BW MSG), MT1, MT2 and MT3 (MSG-induced male mice orally treated with 0.2, 0.4 and 0.6 mg/g BW temulawak (C. xanthorriza) rhizome extract for 14 days, respectively). At the end of treatment, all mice were sacrificed, and mice were sacrificed, and cauda epididymis was isolated. The obtained semen was analyzed for its quality, including motility, viability, concentration and abnormalities of spermatozoa. Data were analyzed using one-way ANOVA and followed by the Tukey test using SPSS for Windows. The results showed that MT1, MT2 and MT3 groups could improve sperm motility of MSG-induced mice (72.26±5.69, 79.16±4.45 and 74.06±4.79 %, respectively). The highest sperm viability was found in the MT2 group (77.83±2.75%) followed by MT1 and MT3 groups (70.19±5.93 and 72.41±5.53%, respectively). MT2 and MT3 groups could increase (p&lt;0.05) sperm concentration in MSG-induced mice by 14.03x106 and 14.46x106 cells/ml, respectively. While, sperm abnormalities of MSG-induced mice tend to decrease in MT1, MT2, and MT3 groups by 38.10, 36.32 and 36.04%. In conclusion, the aqueous extract of C. xanthorriza rhizome significantly improved sperm quality by increasing the motility, viability and concentration of sperm and also altered the sperm abnormality of MSG-induced mice.

Effect of Carbohydrate Type and Phenotype on the Quality of Post-Thawing Frozen Semen of KUB Chicken

The superior Balitbangtan Kampung Chicken (KUB) chickens have different phenotypes. It was reported that the chicken phenotype was related to semen quality. This study aimed to determine the post-thawing characteristics and quality of KUB chicken semen with different phenotypes frozen in Ringer's lactate egg yolk (RLEY) diluent with the addition of fructose or glucose. Semen was collected using the massaging method from 20 KUB chickens with a single comb phenotype and black or dark brown feather color with a red feather neck (SCNR), green-black single comb with white feather neck collar (SCNW), pea comb and black feathers or dark brown fur with a red neck (PCNR), and a green-black pea comb with a white neck (PCNW). Semen from each chicken phenotype was divided into three parts or frozen in three types of diluents: RLEY, RLEY+fructose (RLEYF), and RLEY+glucose (RLEYG). The highest sperm motility was found in the diluent with the addition of glucose in the SCNR and PCNW phenotypes (P0.05). The highest sperm viability was shown in the RLEYG diluent in the PCNW phenotype (P0.05). The highest abnormality was found in the RLEY and RLEYF diluents in the SCNW, PCNR, and PCNW groups, whereas in the RLEYG group, it was only found in the PCNR group. From the results of this study, it can be concluded that the type of glucose and chicken phenotype influences the quality of post-thawing semen. The best is found in diluents with glucose attachments in the SCNR phenotype.

Cryopreservation effect on sperm viability, mitochondrial membrane potential, acrosome integrity and sperm capacitation of alpaca spermatozoa detected by imaging flow cytometry.

Eighty-five sperm samples were cryopreserved and SYBR14/PI, MitoTracker Deep Red FM, FITC-PSA/PI and chlortetracycline were used for imaging flow cytometry evaluation of sperm viability, mitochondrial membrane potential (MMP), acrosome integrity and sperm capacitation, respectively. Sperm motility was also registered. Sperm motility (46.1 ± 7.7 vs. 24.1% ± 6.5%), sperm viability (49.8 ± 11.5 vs. 32.3% ± 9.6%) and high MMP (49.8% ± 12.4% vs. 34.9% ± 9.9%) decreased significantly (p < .05) during cryopreservation process, in contrast to acrosome-reacted in viable spermatozoa (1.0% ± 1.6% vs. 1.0% ± 1.0%) and sperm capacitation (10.0 ± 9.8 vs. 8.2% ± 12.4%) that were similar (p > .05) before and after cryopreservation. Positive correlations were found between sperm motility versus high MMP (r=.63), sperm motility versus sperm viability (r=.67) and sperm viability versus high MMP (r=.88). In conclusion, cryopreservation of alpaca spermatozoa is related to a decrease in sperm motility, sperm viability and high MMP, meanwhile acrosome integrity and sperm capacitation are not affected.

Influence of an exogenous androgen, testosterone propionate on milt quality and short-term preservation of milt of Asian seabass Lates Calcarifer

Asian Seabass Lates calcarifer is widely used for pond and cage culture practice in the Kingdom of Saudi Arabia. A studywas carried out to understand the influence of an exogenous androgen, Testosterone propionate (TP) on milt quality ofL. calcarifer. Intramuscular injection of TP at dose 1.0 ml kg-1 was given to mature male fishes grown in a brood stockpond. A control was also maintained without giving hormone injection. After 36 h of injection, milt was collected and miltquality was assessed for colour, sperm cell concentration, motility and viability of spermatozoa. Short-term preservation ofmilt was carried out in oxygen and marine teleost Ringer’s medium at 4oC for 120 h. No significant change was observedin colour and pH of milt, but nature of milt changed from thick to watery due to hormone injection. Enhanced milt volume(14%) and sperm cell concentration (4%) was noticed in fishes from the treatment group 36 h post-injection, when comparedto control. Sperm motility duration and percentage motility were high in treatment fishes than control. Milt preserved inoxygen medium showed high sperm motility and viability when compared to Ringer’s medium. Intramuscular injection ofTP at 1.0 ml kg-1 improved milt volume and quality and therefore can be used for induced breeding of Asian Seabass. Keywords: Asian Seabass, Hormone, Intramuscular injection, Milt quality, Ringer’s medium, Sperm motility, Testosteronepropionate

Seasonal changes in sperm freezability of sex-reversed female rainbow trout

In order to obtain sex-reversed females of Salmonid fish (SRF; neomales, masculinized females) the hormonal treatment of fertilized eggs or larvae is used. As a consequence, masculinized fish possess less-developed testes without functional spermatic ducts. Therefore, the semen of sex-reversed females is generally characterized by low or highly variable quality and reflects testicular rather than ejaculated semen. The aim of our study was to evaluate the alterations in sperm freezability of sex-reversed female rainbow trout during the progression of the spawning season. Sperm concentration, seminal plasma osmolality, semen pH, gonadosomatic index (GSI) and total sperm production (TSP) were monitored in fresh semen. The sperm motility parameters, adenosine triphosphate (ATP) production and sperm viability were examined throughout the spawning season in fresh and frozen/thawed semen. The day of the spawning season did not affect sperm motility of fresh semen. During the equilibration of semen, 2–3-fold increase in the sperm motility compared to fresh semen on each day of the spawning season was recorded. A decrease in the sperm motility after cryopreservation compared to equilibrated semen on each day of the spawning season was recorded. The highest ATP concentrations in fresh semen were noted on the 21st day of the spawning season, whereas in cryopreserved semen, these values were the highest on the 16th and 21st days of the spawning season. The viability of fresh semen did not change during the spawning season; however, the highest sperm viability after cryopreservation was observed between the 11th and 21st days of the spawning season. These results should be taken into account during the planning of cryopreservation of semen of valuable SRF individuals, which will be further used for fertilization of eggs under hatchery conditions.

Supplementation of melatonin to cooling and freezing extenders improves canine spermatozoa quality measures

BackgroundSperm freezing and cold storage are the two most common assisted reproductive technologies in the canine breeding industry. The freeze-thawing process causes significant detrimental changes in both sperm cell structure and function. Previous research has confirmed that excessive accumulation of un-scavenged free radicals (oxidative stress) plays an important role in the cryopreservation-induced damage to sperm cells. Also, the gradual accumulation of the free radicals during cold storage leads to a decline in the sperm quality markers. Melatonin is an endogenous neurohormone synthesized from tryptophan amino acid by pineal glands. Besides its several well-known physiologic roles, melatonin has a significant antioxidant potential through direct free radical scavenging properties. Therefore, the current study was designed to evaluate the potential in vitro protective properties of melatonin (0.5, 1, and 2 mM) on canine sperm cells after freezing or during long-term cold storage (9 days, 5 °C) on most important sperm in vitro fertility markers.ResultsMelatonin at 0.5, 1- or 2-mM concentrations could preserve significantly higher sperm total motility after 4 days of cold storage. However, only the 1- and 2 mM melatonin concentrations could result in better TM and PM values after 7 days of cold storage. Furthermore, melatonin supplementation could preserve higher sperm viability and acrosome integrity after 7 days of storage. Also, it could have significant protective effects on the cooled sperm DNA integrity. In the freezing section of the current research, melatonin at either 1- or 2-mM concentrations could not improve the sperm post-thaw TM and PM, whereas they improved sperm DNA integrity. Also, the post-thaw plasma membrane functional integrity and sperm velocity parameters were not affected by the treatment. Although DMSO (Dimethyl Sulfoxide) as the melatonin solvent could reduce the level of sperm lipid peroxidation and even improve the post-thaw sperm DNA integrity compared to the negative control, it reduced the post-thaw sperm progressive motility. However, the negative effects were reversed by concurrent melatonin supplementation at 1- and 2-mM concentrations.ConclusionThe addition of 1- or 2-mM melatonin to the canine sperm freezing and cooling media could improve sperm motility, viability, acrosome, and DNA integrity.

Maintaining the Quality of Kacang Buck Semen in Chilled Storage with the Addition of Green Tea Extract in Extender

Kacang goats can be bred through artificial insemination techniques using liquid semen from a superior buck. The study was aimed to determine the quality of Kacang buck semen in chilled storage when green tea extract (GTE) was added to the semen extender. Specifically, 12 ejaculates from three Kacang bucks were diluted in skim milk–egg yolk extender containing 0 mg, 0.05, 0.10, and 0.15 mg of GTE/100 mL. The extended semen was stored at 5°C, and its quality was evaluated daily for 5 d. Comparatively, semen with 0.10 mg of GTE/100 mL had the best quality (p<0.05): it had the highest sperm viability, sperm progressive motility, and sperm intact plasma membrane values, and the lowest malondialdehyde levels and DNA fragmentation percentage. However, as the storage period increased, there was a decrease in sperm viability, sperm motility, and sperm intact plasma membrane values with an increase in malondialdehyde levels and DNA fragmentation (p<0.05). The sperm motility of semen with 0.10 mg of GTE/100 mL was maintained during 5 d of chilled storage to meet the qualification for artificial insemination. In contrast, the sperm motility of semen with 0.05 mg and 0.15 mg of GTE/100 mL was maintained for 4 d, whereas that of the control semen was maintained only for 3 d. Thus, the addition 0.10 mg of GTE/100 mL of skim milk-egg yolk extender seems to help maintain the quality of Kacang goat sperm in chilled storage.

Worker-Born Males Are Smaller but Have Similar Reproduction Ability to Queen-Born Males in Bumblebees.

Simple SummaryIn bumblebee colonies, the authority of male reproduction is not entirely controlled by the queen. Workers who lose mating ability could also produce haploidy males. The conflict over the reproduction of males in bumblebee colonies becomes more evident compared to the higher eusocial honeybees. However, the reproductive characteristics of worker-born males in bumblebees remain unclear. Here, we evaluated the body size and reproductive ability of males produced by worker and queen in Bombus terrestris. Smaller size and slighter individuals’ weight but equally high sperm viability was found in worker-born males compared to that of queen-born males. Moreover, worker-born males performed as excellently as queen-born males in copulation and colony development of the mated queens, such as queen egg laying, colony foundation, and colony size. This study contributes the new knowledge of the reproductive biology of eusocial bees.Queen-worker conflict over the reproduction of males exists in the majority of haplodiplioidy hymenpteran species such as bees, wasps, and ants, whose workers lose mating ability but can produce haploid males in colony. Bumblebee is one of the representatives of primitively eusocial insects with plastic division labor and belongs to monandrous and facultative low polyandry species that have reproductive totipotent workers, which are capable of competing with mother queen to produce haploid males in the queenright colony compared to higher eusocial species, e.g., honeybees. So, bumblebees should be a better material to study worker reproduction, but the reproductive characteristics of worker-born males (WMs) remain unclear. Here, we choose the best-studied bumblebee Bombus terrestris to evaluate the morphological characteristics and reproductive ability of WMs from the queenless micro-colonies. The sexually matured WMs showed smaller in forewing length and weight, relatively less sperm counts but equally high sperm viability in comparison with the queen-born males (QMs) of the queenright colony. Despite with smaller size, the WMs are able to successfully mate with the virgin queens in competition with the QMs under laboratory conditions, which is quite different from the honeybees reported. In addition, there was no difference in the colony development, including the traits such as egg-laying rate, colony establishment rate, and populations of offspring, between the WM- and the QM-mated queens. Our study highlights the equivalent reproductive ability of worker-born males compared to that of queens, which might exhibit a positive application or special use of bumblebee rearing, especially for species whose males are not enough for copulation. Further, our finding contributes new evidence to the kin selection theory and suggests worker reproduction might relate to the evolution of sociality in bees.

Evaluation of extenders for refrigerated preservation ofLabeo rohitamilt

The present study was designed to determine physico-chemical characteristics and best extender for refrigerated preservation of Labeo rohita milt. In experiment I, milt was collected from mature and healthy brooders (n = 5) of L. rohita reared at fish seed hatchery, Rawal Town, Islamabad, Pakistan. After collection, milt was maintained at 4°C and physico-chemical characteristics were studied. The mean volume of Labeo rohita milt was 8.02 ± 0.12 ml, pH 7.60 ± 0.17, sperm count 2.77 ± 0.19 1010/ml, osmolality 267.6 ± 7.4 mOsmol/kg, sodium 95.43 ± 6.7 (mM/L), potassium 34.41 ± 1.2 (mM/L), total lipids 178.94 ± 5.0 mg/dl and motility 83.5 ± 5.0%. In experiment II, nine male brooders (3 brooders/replicate) maintained in three different ponds were used. In each replicate, milt from three brooders was pooled, kept at 4°C and divided into 4 aliquots. An aliquot was kept undiluted (control), while other aliquots were diluted in Alsever's solution, sugar-based extender and modified Kurokura extender (KE) in 1:9 ratio at 4°C and stored up to 7 days. Sperm motility and viability were assessed for up to 7 days. Total antioxidant capacity was measured on Day 4. Sperm motility was higher (p < 0.05) in milt diluted with KE compared with control and other diluents from Day 5 to Day 7. However, highest sperm viability was observed on Day 6 and Day 7 in sperm diluted with KE. Total antioxidant capacity of milt diluted with KE and control was higher than other diluents on Day 4. In conclusion, viability of Labeo rohita sperm can be increased by diluting it in KE.

Effect of Ginger Extract on Semen Parameters and Sperm DNA Fragmentation during the Liquid Storage at 4°C in Native Roosters (Research Note)

The goal of the current study was to determine the effect of ginger extract on some quality parameters of rooster spermatozoa during liquid storage. A total of 10 healthy adult native roosters were selected and sampled twice a week for three weeks. Treatment groups were made up of basal extender supplemented with various concentrations of ginger extract including 0, 20, 40, 60, and 80 μg/mL. Sperm plasma membrane integrity, viability, and motility were assessed at 0, 24, 48, and 72 hours after semen collection. However, the sperm DNA fragmentation test was determined only after 48 hours of storage. The sperm membrane integrity was high at 24 (81.66%) and 48 (58.66%) hours in control and 60 µg/mL of ginger extract, respectively. The highest sperm viability (70.50%) and motility (76.50%) were obtained in 20 μg/mL ginger extract at 48h. The lowest sperm DNA fragmentation (32%) was observed in the 20 μg/mL of ginger extract. According to the results, the ginger extract showed a protective effect against time-associated harmful changes in semen quality of roosters during liquid storage.

Cryopreservation of Indonesian native chicken semen by using dimethyl sulfoxide and various level of ethylene glycol as cryoprotectants

Abstract. Khaeruddin, Junaedi, Hastuti. 2020. Cryopreservation of Indonesian native chicken semen by using dimethyl sulfoxide and various level of ethylene glycol as cryoprotectants. Biodiversitas 21: 5718-5722. Imported purebred chickens are becoming more popular and a regular staple in Indonesia. Therefore, it is necessary to strengthen conservation efforts to preserve Indonesian chickens, one of which is by means of sperm cryopreservation. This study aimed to determine the effects of the addition of DMSO and different concentrations of ethylene glycol to a Ringer’s lactate egg yolk (RLY)-or coconut water egg yolk (CWY)-based extender on the quality of frozen-thawed Indonesian chicken sperm. This study was used nine Indonesian native roosters about 20 months of age. The semen extenders used in this study were RLY + DMSO 7%, RLY + ethylene glycol 3%, RLY + ethylene glycol 5%, RLY + ethylene glycol 7%, CWY + DMSO 7%, CWY + ethylene glycol 3%, CWY + ethylene glycol 5% and CWY + ethylene glycol 7%. Liquid semen was packaged in 0.25 mL straw, then cooled at 5oC for 2 hours, frozen at 5 cm above liquid nitrogen for 10 minutes, following stored in a liquid nitrogen container for 24 hours. The semen straws were thawed at 37oC for 30 seconds. Statistical analysis for multiple comparisons was performed as a completely randomized design with eight treatment levels and seven replications. The results showed that there were no differences in sperm motility, recovery rate, and abnormality between extenders after the freeze-thaw process. Whereas, RLY + DMSO 7% was the highest sperm viability.

Enrichment of bovine X-sperm using microfluidic dielectrophoretic chip: A proof-of- concept study

The microfluidic dielectrophoretic (MF-DEP) chip is a new, economical and readily-available technology that might be used to enrich X-sperm for increasing female offspring in dairy farms. In this study, we sought to develop an MF-DEP chip to enrich X bovine sperm. The MF-DEP chip was composed of an electrode attached to a glass slide and a microchannel made from polydimethylsiloxane. Sex-sorted sperm from flow cytometry were used to identify optimal electric field conditions while unsorted sperm were later tested for sorting efficiency. The results show that during dielectrophoresis some sperm attached to the electrode (called positive DEP; pDEP) whereas other moved away from the electrode (called negative DEP; nDEP). X and Y-sperm responded to dielectrophoresis differently depending on various factors such as buffers, voltages, and frequencies. We found that the condition 4 V 1 MHz significantly reduced (P < 0.05) the percentage of Y-sperm to nearly 30 and therefore enriched X-sperm. The sorting efficiency was dependent on buffer, bull, sorting cycle, flow rate, electrical voltage, and frequency. Notably, the best sorting buffer found in this experiment was the conducting buffer, but this buffer significantly reduced sperm viability and motility. Other sperm-friendly buffers, TRIS and mHTF, were also used, but could not enrich X-sperm. In conclusion, this is a proof of concept that the MF-DEP chip can be effectively used to enrich bovine X-sperm. However, more research must be performed particularly to find the best sorting buffer to effectively sex-sort sperm while providing high motility and sperm viability.

Tolerance of Stored Boar Spermatozoa to Autologous Seminal Plasma: A Proteomic and Lipidomic Approach.

Long-term exposure of liquid preserved boar spermatozoa to seminal plasma (SP) can cause dramatic sperm injury. This study examined whether boar specificity exists in the sensitivity of spermatozoa to SP and whether correspondent biomarkers can be identified. Consecutive ejaculates (n = 4–5) collected from 19 boars were centrifuged, diluted with a pH-stablising extender with 10% (v/v) autologous SP and evaluated by computer-assisted semen analysis and flow cytometry. Up until 144 h storage, four boars showed consistently high sperm motility, viability and mitochondria activity, and one boar showed consistently low values. Intra-boar variability was high in the other boars. Screening of SP (n = 12 samples) for protein markers using mass spectrometry identified three protein candidates of which the granulin precursor, legumain and AWN were 0.5 to 0.9 log2-fold less abundant (p < 0.05) in SP-resistant compared to SP-sensitive samples. Lipidome analysis by mass spectrometry revealed 568 lipids showing no difference between the SP-groups. The most abundant lipids were cholesterol (42,442 pmol), followed by phosphatidylserine (20,956 pmol) and ether-linked phosphatidylethanolamine (13,039 pmol). In conclusion, three candidate proteins were identified which might be indicative of SP-tolerance of sperm during long-term storage. Noteworthy, a first lipidomic profile of boar SP is presented.

Comparison of flow cytometry-based apoptosis detection methods for measuring of human native and cryopreserved spermatozoids viability

The aim of the study was to compare the ability of various media for cryopreservation of sperm to ensure their viability after thawing and to assess the possibility of using Narcissus pseudonarcissus lectin to determine the viability of native and cryopreserved human sperm by flow cytometry.&#x0D; Materials and methods. Used ejaculate 54 men aged 26 to 47 years, undergoing treatment for infertility. The control was a native ejaculate, which was also used for the in vitro fertilization procedure. Four parallel samples were frozen using various commercial media. After storage and thawing, spermatozoa viability was assessed by flow cytometry using three dyes and Narcissus pseudonarcissus lectin.&#x0D; Results. All assays showed that cryopreservation led to a twofold decrease of sperm viability, dye to the changes in the composition and properties of cell membrane, decrease in mitochondrial membrane potential, as well as the damages of acrosomal complex and nucleus. The lowest decrease in sperm viability was shown for Quinns advantage sperm freezing medium for cryopreservation.&#x0D; Conclusion. Flow cytometry makes it possible to evaluate with high efficiency sperm viability as the part of in vitro fertilization. The results of viability assessment using daffodil lectin make the prediction of in vitro fertilization outcome more accurate.

MiR-26a is Involved in Glycometabolism and Affects Boar Sperm Viability by Targeting PDHX.

miR-26a is associated with sperm metabolism and can affect sperm motility and apoptosis. However, how miR-26a affects sperm motility remains largely unknown. Our previous study indicated that the PDHX gene is predicted to be a potential target of miR-26a, which is responsible for pyruvate oxidative decarboxylation which is considered as a key step for connecting glycolysis with oxidative phosphorylation. In this study, we first reported a potential relationship between miR-26a and PDHX and their expressions in fresh, frozen-thawed, and epididymal boar sperm. Then, sperm viability and survival were determined after transfection of miR-26a. mRNA and protein expression level of PDHX in the liquid-preserved boar sperm after transfection were also determined by RT-qPCR and Western Blot (WB). Our results showed that expression level of PDHX was significantly increased during sperm transit from epididymal caput to corpus and cauda. Similarly, expression of PDHX was significantly higher (P < 0.05) in fresh sperm as compared to epididymal cauda and frozen-thawed sperm. However, the expression of miR-26a in epididymal corpus sperm was significantly higher (P < 0.05) than that of caput and cauda sperm. Furthermore, after transfection of boar sperm with miR-26a mimic and inhibitor under liquid storage, the lowest and highest sperm viability was observed in miR-26a mimic and inhibitor treatment (P < 0.05), respectively. The protein levels of PDHX, after 24 and 48 h of transfection of miR-26a mimics and inhibitor, were notably decreased and increased (P < 0.05), respectively, as compared to negative control (NC) group. In conclusion, the novel and enticing findings of our study provide a reasonable evidence that miR-26a via PDHX, a link between glycolysis and oxidative phosphorylation, could regulate the glycometabolic pathway which eventually affect boar sperm viability and survival.

Effect of substituting different concentrations of soybean lecithin and egg yolk in tris-based extender on goat semen cryopreservation

This study aimed to investigate the effects of different concentrations of soybean lecithin (SL; 0.5%, 1%, and 1.5%) and egg yolk (EY) in Tris-based extenders on the semen quality parameters of post-thawed goat semen. Sixteen ejaculates were collected from eight healthy, mature Chongming White goats (3–5 years of age). Each ejaculate was divided into five equal aliquots, and then each pellet was diluted with one of the five Tris-based extenders containing 20% EY, 0.5% SL, 1% SL, 2% SL, or 3% SL. The cooled diluted semen was loaded into 0.5 mL polyvinyl French straws and cryopreserved in liquid nitrogen. Frozen semen samples were thawed at 37 °C and assessed for sperm motility, viability, plasma acrosome integrity, membrane integrity, and mitochondria integrity, and the spermatozoa were assessed for reactive oxygen species (ROS), superoxide dismutase (SOD), and malondialdehyde (MDA). The semen extended in the 2.0% SL extract tended to have a higher sperm viability (57.44%), motility (52.14%), membrane integrity (45.31%), acrosome integrity (52.96%), and mitochondrial activity (50.21%) than the other SL-based extender concentrations (P < 0.05). The 2.0% SL treatment group was equivalent to the semen extended in 20% EY (P > 0.05). The extenders supplemented 20% EY or 2.0% SL significantly increased the SOD activity and decreased the ROS and MDA activities compared to the other groups (P < 0.05). In conclusion, the extenders supplemented with 20% EY and 2.0% SL had similar effects on spermatozoa preservation. These results indicate that a soybean lecithin-based diluent may be used as an alternative extender to egg yolk for the cryopreservation of goat semen.

Complex interactions between sperm viability and female fertility

Sperm viability is a major male fitness component, with higher sperm viability associated with enhanced sperm competitiveness. While many studies have focussed on sperm viability from the male fitness standpoint, its impact on female fitness is less clear. Here we used a panel of 32 isogenic Drosophila simulans lines to test for genetic variation in sperm viability (percentage of viable cells). We then tested whether sperm viability affected female fitness by mating females to males from low or high sperm viability genotypes. We found significant variation in sperm viability among genotypes, and consistent with this, sperm viability was highly repeatable within genotypes. Additionally, females mated to high sperm viability males laid more eggs in the first seven hours after mating, and produced more offspring in total. However, the early increase in oviposition did not result in more offspring in the 8 hours following mating, suggesting that mating with high sperm-viability genotypes leads to egg wastage for females shortly after copulation. Although mating with high sperm-viability males resulted in higher female fitness in the long term, high quality ejaculates would result in a short-term female fitness penalty, or at least lower realised fitness, potentially generating sexual conflict over optimal sperm viability.