Effect of egg yolk plasma and soybean lecithin on rooster frozen-thawed sperm quality and fertility

Optimization of Cholesterol-Loaded Cyclodextrin Combined with Soybean Lecithin as a Cryoprotectant for Rooster Sperm

There are many applications of soybean lecithin (SL) and cholesterol-loaded cyclodextrin (CLC) in sperm freezing processes. To the best of our knowledge, there have been few cases of the combined use of SL and CLC in freezing rooster semen. We investigated the effects of CLC, SL, and their combination on rooster sperm cryodamage. Three experiments were conducted: experiment 1, SL (0.5%, 1%, 1.5%, 2.0%); experiment 2, CLC (1.25 mg, 2.5 mg, 5 mg, 10 mg, 15 mg); and experiment 3, CLC + SL (2.5 mg + 0.25%, 2.5 mg + 0.5%, 2.5 mg + 1%, 2.5 mg + 1.5%). Semen samples were cryopreserved using a programmed cryostat, followed by the determination of post-thaw sperm quality, antioxidant indices, and hatching. The results showed that the combination of 2.5 mg CLC + 0.5% SL had the most significant synergistic effect on cryodamage, and the viability (56.69%), motility (54.35%), mitochondrial activity (54.23%), plasma membrane integrity (53.52%), acrosome integrity (54.71%), and antioxidant activity (MDA concentration: 5.65 nmol/mL; SOD activity: 152.73 U/mL) were significantly greater than those of the other combinations (p < 0.05). Nevertheless, the combined CLC and SL addition group did not substantially increase the fertilization and hatching rates of frozen semen compared with the addition of 2.5 mg CLC. In conclusion, the addition of 2.5 mg CLC and 2.5 mg CLC + 0.5% SL enhanced the quality and fertility of frozen rooster sperm.

In Vitro and In Vivo Evaluation of the Fertilization Capacity of Frozen/Thawed Rooster Spermatozoa Supplemented with Different Concentrations of Trehalose

The objective of this study was to evaluate the impact of the supplementation of varying concentrations of the impermeable disaccharide trehalose on the in vitro and in vivo fertilization capacity of cryopreserved rooster spermatozoa in the original Czech Golden Spotted Hen breed. The control trehalose concentration was 0 mM, while TRE50 (50 mM), TRE100 (100 mM), and TRE200 (200 mM) were used as experimental trehalose concentrations. The kinematic and functional parameters of frozen/thawed spermatozoa were evaluated in vitro using mobile computer-assisted sperm analysis and a flow cytometer. The addition of 100 mM trehalose demonstrated the most favorable results for total (34.17%) and progressive (3.57%) motility after thawing. A statistically significant difference was found for these kinetic parameters compared to the other monitored concentrations. This experimental group was also found to have a significantly higher percentage of spermatozoa without plasma membrane or acrosome damage (33.37%) compared to the TRE50 group (30.74%; p < 0.05) and the TRE200 group (29.05%; p < 0.05). In vivo, artificial insemination was performed to verify fertilization ability. Hens (n = 40) were artificially inseminated twice (10 hens/treatment) with a 3-day interval between inseminations. In conclusion, the addition of 100 mM trehalose significantly improved total and progressive motility after thawing and preserved plasma membrane and acrosome integrity (p < 0.05). The fertilization rate of eggs fertilized with semen frozen with the addition of 100 mM trehalose was not significantly different from the other concentrations tested or the control group but was numerically higher (23.21% vs. 15.20% of fertilized eggs in this group).

Evaluation of the effect of lecithin and nanolecithin in repairing membrane damage, maintaining membrane integrity, and improving human sperm function in the freezing-thawing process

PURPOSE

Our study aimed to evaluate the effects of lecithin nanoparticles on sperm quality during cryopreservation.

METHODS

In phase one, sperm-freezing media were prepared with lecithin concentrations (0.5%, 1%, and 2%) and lecithin nanoparticles of various sizes (50-100, 100-200, and ≥ 200 nm). Post-thaw, sperm motility, viability, mitochondrial membrane potential (MMP), lipid peroxidation (measured by malondialdehyde, MDA), and DNA fragmentation were evaluated. In phase two, the acrosomal reaction was assessed in the best and worst-performing groups from phase one. DiI labeling detected interactions between lecithin nanoparticles and the sperm membrane. Field emission scanning electron microscopy (FESEM) examined the sperm membrane's surface structure and lecithin binding sites. Atomic force microscopy (AFM) assessed height differences in the sperm surface layer in the best-performing group from phase one.

RESULTS

The group treated with 1% lecithin nanoparticles (50-100 nm) showed significantly increased viability post-thaw compared to other groups, with reduced DNA fragmentation and MDA levels. While motility significantly decreased in all groups compared to before freezing levels, lower concentrations, and smaller particle sizes yielded better results. MMP also significantly decreased across all groups with no significant differences. The acrosomal reaction significantly decreased with 1% lecithin nanoparticles (50-100 nm) compared to the 2% (≥ 200 nm) group. DiI-labeled nanoparticles and FESEM revealed that lecithin nanoparticles primarily bound to and infiltrated the sperm membrane, particularly in the head and postacrosomal regions.

CONCLUSIONS

Lecithin nanoparticles effectively bind to the sperm membrane, protecting it during the freeze-thaw process and improving sperm viability.

Effect of naringenin on post-thaw quality, fertility-associated gene expression and fertilization potential of buffalo (Bubalus bubalis) bull sperm

Our objectives were to explore the effect of naringenin addition in the semen extender on the post-thaw 1) sperm quality, 2) fertility-associated gene expression, and 3) fertilization potential of buffalo bull sperm. In experiment 1, semen samples (n = 32) from four Nili-Ravi buffalo bulls were pooled (n = 8) and diluted with the tris-citric acid (TCF-EY) extender containing different concentrations of naringenin, i.e., placebo (DMSO), 0 (control), 50, 100, 150 and 200 μM naringenin. After dilution, semen samples were packed in 0.5 mL French straws, cryopreserved and analyzed for post-thawed sperm quality and gene expression. Computer-assisted Semen Analysis, Hypo-osmotic Swelling test, Normal Apical Ridge assay, Rhodamine 123, Acridine orange, Propidium iodide staining and Thiobarbituric Acid Reactive Substances assay were performed to assess sperm motility parameters, plasma membrane functionality, acrosome integrity, mitochondrial membrane potential, DNA integrity, viability and lipid peroxidation, respectively. Expression levels of sperm acrosome-associated SPACA3, DNA condensation-related PRM1, anti-apoptotic BCL2, pro-apoptotic BAX, and oxidative stress-associated ROMO1 genes were evaluated through qPCR. Results revealed that total and progressive motility, plasma membrane functionality, acrosome integrity, mitochondrial membrane potential, DNA integrity and viability were higher (P < 0.05) with 50, 100 and 150 μM naringenin compared to 200 μM naringenin, placebo and control groups. Moreover, all naringenin-treated groups improved catalase activity, and reduced lipid peroxidation compared to placebo and control groups (P < 0.05). Relative expression levels of SPACA3 and PRM1 genes were higher (P < 0.05) with 150 μM naringenin compared to all groups except 100 μM (P > 0.05). No difference (P > 0.05) in the expression level of BCL2 gene was observed among all groups. Furthermore, BAX gene was expressed higher (P < 0.05) in the 200 μM naringenin group, whereas no difference (P > 0.05) in expression was noticed among the remaining groups. In addition, ROMO1 gene was expressed lower (P < 0.05) in all naringenin-treated groups compared to the control. In experiment 2, the in vivo fertility of semen doses (n = 400; 200/group) containing optimum concentration of naringenin (150 μM; depicted better in vitro sperm quality in experiment 1) was compared with control during the breeding season. Buffaloes were inseminated 24 h after the onset of natural estrus and palpated transrectal for pregnancy at least 60 days post-insemination. The fertility rate of 150 μM naringenin group was higher (P = 0.0366) compared to the control [57.00 ± 0.03 % (114/200) vs. 46.50 ± 0.04 % (93/200), respectively]. Taken together, it is concluded that naringenin supplementation in semen extender improves post-thaw quality, fertility-associated gene expression and fertilization potential of buffalo bull sperm, more apparently at 150 μM concentration.

Gallic acid supplementation partially ameliorates reproductive aging in rooster breeders by improving semen quality, sperm kinetics, hormones, and antioxidant status

Aging leads to decreased fertility in roosters, which is likely due to increased oxidative stress. This study evaluated the antioxidant effects of gallic acid (GA) supplementation on sperm quality and fertility of aged roosters. This study evaluated whether GA supplementation can mitigate age-related fertility decline. Roosters were randomly assigned to: control, 100 mg/kg GA, or 200 mg/kg GA. Semen parameters, sperm kinetics, hormone levels, fertility rate, and hatchability were assessed. GA increased semen concentration, membrane integrity and viability while decreasing defects versus control (P < 0.01). Testosterone was higher in GA groups (P<0.01) without affecting gonadotropins. Furthermore, 200 mg/kg GA optimized motility, velocity, linearity, and beat cross frequency versus control and 100 mg/kg GA (P < 0.01). Fertility and hatchability were higher in both GA groups. In conclusion, GA supplementation in aged roosters improves sperm quality, antioxidant status, testosterone, and fertility outcomes, likely by mitigating oxidative stress. The 200 mg/kg dose elicited optimal effects on motion parameters.

Collection, Handling, and Preservation of Wild Bird Semen: Current Status, Challenges, and Perspectives

Semen preservation is a significant biotechnology used to safeguard the genetic material of birds, especially those with declining populations, through biobanking. However, there are limited reports on the successful chilling or cryopreservation of wild bird semen. In general, these techniques are not yet well-established for several species of wild birds and pose several challenges such as the need for bird handling and training, contamination of semen samples, low volume of semen collected, and inefficient preservation protocols. To address these challenges and improve post-thawing outcomes, new possibilities are being investigated, including alternative collection methods to traditional digital massage, the use of antioxidants and enzymes in the medium for chilling or freezing, storage methods using different straws from the usual pellet, and slower freezing rates. This review aims to discuss the various aspects of applying semen preservation in wild birds to create germplasm banks, highlighting the primary results obtained and the challenges that need to be addressed.

Effects of different extenders on epigenetic patterns and functional parameters of bull sperm during cryopreservation process

The cryopreservation process induces alterations in cellular parameters and epigenetic patterns in bull sperm, which can be prevented by adding cryoprotectants in the freezing extenders. The purpose of this study was to compare the protective effects of two extenders based on soybean lecithin (SLE) and egg yolk (EYE) on epigenetic patterns and quality parameters of sperm such as motility parameters, mitochondrial membrane integrity, DNA fragmentation, viability, and apoptotic-like changes of bull sperm after cryopreservation. Results demonstrated that cryopreservation significantly (p < .05) reduced the level of DNA global methylation, H3K9 histone acetylation, and H3K4 histone methylation in both frozen groups compared to the fresh sperm. Also, the level of H3K9 acetylation was lower in the frozen SLE group (21.2 ± 1.86) compared to EYE group (15.2 ± 1.86). In addition, the SLE frozen group had a higher percentage of viability, progressive motility, and linearity (LIN) in SLE frozen group compared to EYE frozen group. However, no difference was observed in mitochondrial membrane integrity and DNA fragmentation between SLE and EYE frozen groups. While soybean-lecithin-based extender showed some initial positive impacts of epigenetics and semen parameters, further investigations can provide useful information for better freezing.

Effects of dietary Moringa oleifera leaf extract on semen characteristics, fertility, and hatchability in aged broiler breeder roosters

Declining semen quality will have a negative impact on the fertility of aged roosters. Various factors influence this decrease in quality. This study was conducted to investigate the effects of different levels of Moringa plant extract on semen characteristics, fertility, and hatchability in aged broiler breeder roosters. A total of 24 roosters were fed 1 of 4 dietary supplements for 10 wk: Control, 100 μL/kg (Moringa oleifera leaf extract [MOLE]-100), 200 μL/kg (MOLE-200), or 400 μL/kg body weight (MOLE-400) of Moringa oleifera extract. Results showed supplementation with MOLE-200 significantly improved (P < 0.05) semen concentration, total motility, progressive motility, sperm membrane integrity compared to other treatments. However, semen volume and body weight were unaffected (P > 0.05). Sperm lipid peroxidation, as indicated by malondialdehyde concentration, was lowest in MOLE-200. There was a significant difference observed among the treatments in terms of total antioxidant capacity (TAC) results. The testosterone concentration in the MOLE-200 treatment was significantly higher than the other treatments (P < 0.05). However, no significant differences were observed in the levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) hormones among the experimental treatments. Fertility and hatchability rates were measured at the end of the trial. Fertility, defined as the number of fertilized eggs, was greatest in the MOLE-200 treatment compared to the other treatments. Similarly, hatchability (hatched chicks/fertilized eggs %) was highest at 88.02% for MOLE-200. In conclusion, dietary supplementation with M. oleifera extract improved semen quality, fertility, and hatchability in aged broiler breeder roosters.

The Effects of Glycerophospholipid Nanomicelles on the Cryotolerance of Frozen-Thawed Rooster Sperm

Semen banking is an efficient method of artificial insemination for commercial breeders. However, the cryopreservation process induces severe damages to plasma membranes, which leads to reduced fertility potential of thawed sperm. The replacement of membrane lipids with oxidized membrane lipids repairs the cell membrane and improves its stability. The aim of this study was to investigate the effects of glycerophospholipid (GPL) nanomicelles on the cryosurvival of thawed rooster semen. Semen samples were collected from six 29-week Ross broiler breeder roosters, then mixed and divided into five equal parts. The samples were diluted with the Beltsville extender containing different concentrations of GPL according to the following groups: 0 (GPL-0), 0.1% (GPL-0.1), 0.5% (GPL-0.5), 1% (GPL-1), and 1.5% (GPL-1.5), then diluted semen was gradually cooled to 4°C during 3 hours and stored in liquid nitrogen. The optimum concentration of GPL was determined based on the quality parameters of thawed sperm. Our results showed sperm exposed to GPL-1 had significantly increased motion parameters and mitochondrial activity. The percentages of viability and membrane integrity were significantly higher in the GPL-1, and GPL-1.5 groups compared with the other groups (p < 0.05). Moreover, the lowest rate of apoptosis and lipid peroxidation were observed in the GPL-1 and GPL-1.5 groups in comparison with the frozen control group. Our findings indicated that membrane lipid replacement with GPL nanomicelles (1% and 1.5%) could substitute for damaged lipids in membranes and protect sperm cells against cryoinjury.

Evaluation of Chicken Egg Yolk Plasma and Low-Density Lipoprotein Alone or Enriched with Ewe or Cow Skim Milk in Tris-Citric Acid-Based Diluent for Cryostorage of Ram Semen

The main purpose of the current study was to find suitable and optimum levels of protectants among chicken egg yolk plasma (CEYP) and low-density lipoproteins (LDLs), alone or supplemented with ewe or cow skim milk, for cryopreservation of ram semen. In Experiments 1 and 2, the CEYP (28%) freezing extender was enriched with ewe or cow milk (2.5%, 5%, 10%, or 20%; v/v), respectively. In Experiments 3 and 4, the semen extender was prepared by varying the amounts of fresh or lyophilized LDL (lyo-LDL), respectively. Finally, ewe or cow skim milk was added to the freshly extracted LDL extender and the quality of frozen-thawed semen was examined (Experiments 5 and 6). Kinematics of spermatozoa (assessed using a computer-assisted sperm analysis system), viability, functionality of the plasma membrane, and levels of malondialdehyde (MDA) and total antioxidant capacity (TAC) were evaluated. Results revealed that addition of ewe or cow skim milk (5%, 10%, or 20%; v/v) to the CEYP diluent enhanced kinematics, viability, and membrane integrity of spermatozoa compared with the control (p < 0.05). Moreover, fresh LDL diluent was more effective than lyo-LDL in the cryosurvival of ram spermatozoa. In addition, enrichment of fresh LDL diluent with ewe or cow skim milk improved different variables of spermatozoa compared with the control (p < 0.05). Levels of MDA and TAC were not affected by adding ewe or cow milk to the diluents (p > 0.05). In conclusion, enrichment of fresh LDL extenders with ewe or cow milk also is proposed as an approach to preserve ram semen quality against cold shock and cryodamage injuries.

Enhancing post-thaw quality of ram epididymal sperm by supplementation of rutin in cryopreservation extender

The purpose of this study was to examine the effect of different rutin concentrations on rams epididymal sperm. A local slaughterhouse provided 50 pair of testes from 25 rams. The testes were sent to the lab at room temperature. Spermatozoa were extracted by suspending portions of cauda epididymis in tris solution. Ram sperm was cryopreserved (in liquid nitrogen) in a tris extender containing rutin at 0, 0.5, 0.75, 1, and 1.25 mM. Rutin showed superior sperm total and progressive motility, beat cross frequency, straight line velocity, velocity average pathway and membrane integrity values at 0.75 and 1 mM. The morphology of the sperm and the superoxide dismutase levels did not significantly change with different treatments. Moreover, rutin at 0.75 and 1 mM was also shown to have the highest level of mitochondrial activity. The results showed ATP, total antioxidant capacity, and glutathione peroxidase levels were significantly greater in the rutin 0.75 and 1 mM groups (P < 0.05). Rutin at 0.75 and 1 mM levels had the lowest reactive oxygen species concentrations. Rutin at 0.75 and 1 mM substantially increased the proportion of viable sperm (P < 0.05). The lowest amount of apoptosis was observed in 0.75 and 1 mM rutin. Rutin at 0.75 and 1 mM yielded the least significant percentage of dead sperm. It may be inferred that adding 0.75 and 1 mM to the sperm extender can enhance the quality of the epididymal sperm in rams after the cryopreservation process.

Effect of different sources of dietary zinc on sperm quality and oxidative parameters

Zinc has a critical physiological role in sperm function. The purpose of this study was to investigate the effect of different sources of zinc on sperm quality. For this purpose, 18 Zandi lambs with an average weight of 32 ± 1.2 kg were subjected to three treatments in a completely randomized design. Experimental treatments include (1) control treatment of basal diet without zinc supplementation, (2) basal diet with 40 mg/kg of zinc supplementation from zinc sulfate source and (3) basal diet with 40 mg/kg of zinc supplementation with organic source. At the end of feeding period, lambs were slaughtered. To determine the effect of experimental treatments on sperm quality, the testes were transferred to the laboratory. After that, epididymal spermatozoa were evaluated for sperm motility parameters, abnormal morphology, viability, membrane functionality, malondialdehyde (MDA) and antioxidant activity [glutathione peroxidase (GPx), superoxide dismutase (SOD), total antioxidant capacity (TAC)], sperm concentration and testosterone level. Zinc sulfate administration decreased MDA levels compared to other treatments and increased GPx and TAC activity compared to the control (P < 0.05), although SOD activity was not affected by any supplementation. Also, the use of zinc sulfate supplementation increased the percentage of total and progressive motility compared to the control group (P < 0.05). Membrane integrity and sperm viability were also affected by zinc sulfate supplementation (P < 0.05). Therefore, the results of this study showed that the use of zinc sulfate, can improve sperm motility and survival indices and its antioxidant capacity.

Fertility results after exocervical insemination using goat semen cryopreserved with extenders based on egg yolk, skim milk, or soybean lecithin

To evaluate the effects of four extenders on the post-thaw quality and fertility of goat semen, six Yunshang Black bucks' semen was collected, pooled, diluted with Andromed® (Andr®), Optidyl® (Opt®), P3644 Sigma l-phosphatidylcholine (l-α SL), and skim milk-based (Milk) extenders, and then cryopreserved. The sperm motilities, abnormalities, membrane and acrosome integrity, mitochondrial activity, apoptosis, and reactive oxygen species (ROS) production were evaluated after thawing. After exocervical insemination with the thawed semen, the pregnancy, lambing, and twinning rates were recorded and compared. The results showed that sperm motilities, membrane integrity, acrosome integrity, mitochondrial activity, and viable spermatozoa were significantly higher in the Andr® and Opt® groups than those in the l-α SL and Milk groups (p < .05). Furthermore, there was no difference between Andr® and Opt® (p > .05). The sperm abnormality was lower in semen frozen with the Andr® or Opt® extenders, as compared to the l-α SL or Milk extender (p < .05). Regarding, the viable cells with low ROS production, the optimal results were obtained in the semen frozen with Andr® and Opt® extenders. Following exocervical insemination, the pregnancy and lambing rates in the Milk group were significantly lower than those in the other groups (p < .05). No difference was found in the pregnancy and lambing rates between Andr®, Opt®, and l-α SL (p > .05). Furthermore, the twinning rates were similar between these four groups (p > .05). In conclusion, egg yolk or skim milk can be substituted by soybean lecithin during cryopreservation of goat semen.

Effects of adding mixed chicken and quail egg yolks to the cryodiluent on the quality of ram semen before and after cryopreservation

The effects of adding mixed chicken and Japanese quail egg yolks (EYs) to the cryodiluent on the quality of ram semen before freezing and post-thawing were evaluated. Additionally, the composition of chicken and quail egg EYs and their mixture were analyzed for results explanation. The semen was collected from rams (n = 5) and extended with cryodiluent containing the EY of chicken, quail or their mixture (1:1). The extended semen was chilled slowly to 5 °C within 2 h and equilibrated for 2 h, before frozen on the liquid nitrogen vapor and cryopreserved at -196 °C. The straws were evaluated before freezing and post-thawing for sperm motility, vitality and abnormality besides plasma-membrane and DNA integrities. The moisture, ash, protein, and fatty acid (FA) contents of chicken EY, quail EY and their mixture were analyzed. Sperm vitality, plasma membrane integrity and DNA integrity before freezing were significantly (P < 0.05) higher in quail EY than chicken EY and mixed EYs cryodiluent. The chicken EY extender significantly improved the vitality, plasma membrane and DNA integrities of post-thawed ram semen in comparison with quail EY or mixed EYs extenders. While, the post-thawing sperm abnormalities was lower (P ≤ 0.05) in quail EY than chicken EY and mixed EYs cryodiluent. The post-thawing sperm motion kinetics parameters were higher in quail EY than chicken EY and mixed EYs cryodiluent. The highest percentages of moisture, ash, saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) were detected in quail EY had. While, the highest percentages of fat, protein and polyunsaturated fatty acids (PUFAs) were detected in chicken EY. In conclusion, using of chicken EY can improve total motility, vitality, plasma membrane integrity and DNA integrity of cryopreserved ram semen. While, using of quail EY can improve sperm abnormalities and kinetic motion parameters of cryopreserved ram semen. Mixing chicken and quail EYs added no value for post-thawing ram semen parameters.

Poultry genetic heritage cryopreservation and reconstruction: advancement and future challenges

Poultry genetics resources, including commercial selected lines, indigenous breeds, and experimental lines, are now being irreversibly lost at an alarming rate due to multiple reasons, which further threats the future livelihood and academic purpose. Collections of germplasm may reduce the risk of catastrophic loss of genetic diversity by guaranteeing that a pool of genetic variability is available to ensure the reintroduction and replenishment of the genetic stocks. The setting up of biobanks for poultry is challenging because the high sensitiveness of spermatozoa to freezing–thawing process, inability to cryopreserve the egg or embryo, coupled with the females being heterogametic sex. The progress in cryobiology and biotechnologies have made possible the extension of the range of germplasm for poultry species available in cryobanks, including semen, primordial germ cells, somatic cells and gonads. In this review, we introduce the state-of-the-art technologies for avian genetic resource conservation and breed reconstruction, and discuss the potential challenges for future study and further extending of these technologies to ongoing and future conservation efforts.

Protective effect of rosiglitazone on microscopic and oxidative stress parameters of ram sperm after freeze-thawing

The purpose of this study was to investigate the effects of rosiglitazone on ram semen after cryopreservation on the quality of thawed sperm. Sperm motility, membrane functionality, viability, total abnormality, acrosome membrane integrity, mitochondrial activity, reactive oxygen species production, ATP content and apoptotic features were assessed after thawing. Rosiglitazone at concentration of 60 µM resulted in the highest (P < 0.05) total motility, progressive motility and straight-line velocity. The percentages of average path velocity and curvilinear velocity were greater in the 60 µM group. Different concentrations of rosiglitazone did not have significant effects on amplitude of the lateral head displacement, linearity and straightness. The highest amounts of membrane functionality and mitochondrial activity after freeze-thawing were observed in groups containing 60 µM. By increasing the rosiglitazone level to 80 µM, no positive effect was observed in most of the evaluated parameters. The lowest ROS concentration was recorded in 60 µM rosiglitazone group (P < 0.05). The group containing 60 µM rosiglitazone also produced the lowest significant percentage of apoptosis-like changes and dead sperm. A greater (P < 0.05) percentage of acrosome integrity in frozen-thawed spermatozoa was observed in the 60 µM rosiglitazone group. There was no significant difference between 40 and 60 µM rosiglitazone in intact acrosome of ram thawed semen. The result showed that supplementation in ram semen extender with rosiglitazone had a positive role in the regulation of ram sperm motility and had strong protective effect on the sperm membrane and acrosome integrity.

Comparison of the performance of targeted mitochondrial antioxidant mitoquinone and non-targeted antioxidant pentoxifylline in improving rooster sperm parameters during freezing and thawing

Oxidative stress is associated with impaired sperm quality after thawing. Since mitochondria are the main source of reactive oxygen species (ROS) in sperm, the aim of this study was to investigate the effects of targeted mitochondrial antioxidant mitoquinone (MitoQ) and non-targeted mitochondrial antioxidant pentoxifylline (PTX) during cooling and cryopreservation of rooster sperm. Sperm samples were collected from 15 roosters aged 28 wk and diluted with Beltsville extender. After dilution and addition of treatments (50, 100, and 200 pMol MitoQ and 0.5, 0.75, and 1 μM PTX), samples were cooled for 2 h to 4°C and they were first analyzed at this stage and were frozen and re-evaluated after thawing. After the freezing and thawing, level of 100 pMol MitoQ significantly increased total motility (TM), progressive motility (PGM), curvilinear velocity (VCL), membrane integrity, viability, total antioxidant capacity (TAC) and the glutathione peroxidase (GPx), as well as the level of 50 pMol significantly increased TM, PGM, average path velocity (VAP), straight-line velocity (VSL), membrane integrity, viability, and mitochondrial activity. Moreover, these 2 levels (50 and 100 PMol) decreased malondialdehyde and sperm with abnormal morphology. Addition of 0.75 μM PTX also increased total motility compared to the control group and levels of 0.5 and 0.75 μM decreased sperm with abnormal morphology. It could be concluded the addition of MitoQ and PTX can be useful for sperm cryopreservation industry and reduce the harmful effects of freeze-thawing.

Spermatozoa Survival in Egg Yolk-Based and Soybean-Based Extenders at Ambient and Chilling Temperature in Domestic Turkeys (Meleagris gallopavo)

Populations of many galliform species have declined mainly due to habitat loss and over-hunting, notably the Congo peacock, which has been classified as a vulnerable species by the International Union for Conservation of Nature (IUCN). The domestic turkey, being a species of least concern, which has been reported to be closely related to peacocks, could serve as a model for the optimization of assisted reproductive technologies for the Congo peacock. This study was aimed at developing a suitable turkey semen extender for artificial insemination in field conditions. Semen was collected using the dorso-abdominal massage technique from seven turkey toms and analyzed. Ejaculates with >70% motility and >80% live spermatozoa were pooled and divided into four aliquots (four treatments). Each of the four treatments was extended in a soybean-based extender or an egg yolk-based extender, with or without L-ascorbic acid. Two liquid preservation protocols (ambient temperature (35 °C) and chilled (4 °C)) were employed, and quality parameters including motility, viability and morphology were evaluated. The results show that the two extenders were similar with regard to semen quality parameters, and L-ascorbic acid supplementation of the turkey semen extenders improved semen quality during liquid storage.

Comparing the effect of rooster semen extender supplemented with gamma-oryzanol and its nano form on post-thaw sperm quality and fertility

Antioxidant nanoparticles include the potential for improving sperm cryopreservation. The aim of performing this study was to evaluate the effects of gamma-oryzanol (GO) at 0 (C) (control group), 20 (GO20), 40 (GO40), 60 (GO60), 80 (GO80), and 100 (GO100) µM and gamma-oryzanol nanoparticles (GON) at 0 (CN), 20 (GON20), 40 (GON40), 60 (GO60), 80 (GON80), and 100 (GON100) µM on post-thawed sperm quality and fertility of rooster sperm. Sperm motility, plasma membrane integrity, total abnormality, mitochondrial activity (Rhodamine 123), apoptotic features (Annexin V/Propidium iodide), reactive oxygen species (ROS) production, ATP content and the fertility and hatchability were evaluated after thawing. Total motility in GON60 and GON80 were significantly higher compared to control groups (C and CN). GON80 showed the greatest percentages of progressive motilities. When GO80, GON60, and GON80 were added to the cryopreservation medium, the plasma membrane functionality of the semen samples improved. The minimum abnormality of spermatozoa is observed in the group treated with GON80. The groups treated with GON60 and GON80 had greater (P < 0.05) mitochondrial activity. The level of sperm ROS after cryopreservation was significantly lower in GON60 and GON80 groups. Live sperm was significantly higher (P < 0.05) in GON60 and GON80 group compared to other groups. GON60 and GON80 groups also led to the lowest significant percentage of apoptosis-like change sperm. Greater fertility percentages were observed (P < 0.05) when sperm were stored in extenders treated with GON60 and GON80. GON80 resulted in significantly improved hatched eggs compared to C, GO60, GO180 and CN. In conclusion, supplementation of Lake extender with 60 and 80 µM gamma-oryzanol nanoparticles could be a proper process to improve freeze-thawing rooster sperm quality leading to better freeze/thaw characteristics.

Does ergothioneine and thawing temperatures improve rooster semen post-thawed quality?

The present study focuses on the effect of different levels of ergothioneine and thawing temperature on rooster semen cryopreservation. Semen was diluted in Lake extender containing ergothioneine at 5, 10, 15, and 20 µM and cryopreserved. Two thawing temperatures (37°C for 30 s and 60°C for 5 s) were consequently examined. Sperm motility parameter, membrane integrity, abnormal morphology, viability, apoptotic status, mitochondria activity, and lipid peroxidation were determined after freeze-thaw process. Ergothioneine levels of 5 and 10 µM led to higher (P < 0.05) total motility (66.58 ± 1.44 and 72.11±1.44, respectively) and average path velocity (VAP) (34.54 ± 0.89, 37.28 ± 0.89, respectively). Higher (P < 0.05) significant membrane integrity and mitochondria activity after freeze-thawing were observed in the groups supplemented with 10 µM ergothioneine (68.62 ± 1.24 and 69.12 ± 1.26, respectively). Also, 5 and 10 µM of ergothioneine led to the lowest significant percentage of apoptotic and dead sperm. The total motility and progressive motility resulted in significantly (P < 0.05) higher amount when sperm were thawed with 60°C (60.58 ± 0.91 and 24.76 ± 0.53, respectively) compared to thawed sperm in 37°C. The membrane integrity, viability and mitochondria activity led to significantly (P < 0.05) higher when sperm were thawed with 60°C (58.2 ± 0.78, 63.21 ± 0.80 and 56.85 ± 0.79, respectively). It could be concluded the addition of 5 and 10 µM ergothioneine in the semen extender and thawing temperature at 60˚C in 5 s can be an efficient strategy to preserve rooster cryopreserved semen quality.

Beneficial Influence of Soybean Lecithin Nanoparticles on Rooster Frozen-Thawed Semen Quality and Fertility

Simple Summary

Soy lecithin (SL) can be used in to prevent spermatozoa cryodamage during cryopreservation by mitigating the efflux of cholesterol or phospholipids, thus reducing the formation of intracellular ice crystals. SL nanoparticles (nano-SL) have a smaller particle size and higher solubilizing capacity as compared with those that have not undergone nanotreatment. Thus, they allow for a better interaction or coating of sperm, decreasing cold shock injury during freezing–thawing processes. The objective of this study was to determine the optimal concentration of nano-SL. In order to achieve this, we assessed the quality of frozen–thawed semen in vitro and in vivo. We found that a nano-SL dosage of 1.0% in the semen extender had an affirmative influence on post-thawing quality in roosters, improving various parameters related to sperm motion, protecting the membrane and acrosome integrities, increasing mitochondrial activity and antioxidant capacity, and reducing the oxidative stress caused by the cryopreservation process. Moreover, enrichment of 1.0% nano-SL in the semen extender improved the fertilizing capacity of rooster sperm after artificial insemination.

Abstract

The present study aimed to investigate the impact of different concentrations (0%, 0.5%, 1.0%, 1.5%, and 2.0%) of nano-soybean lecithin (SL) in the extender on sperm quality, sperm motion characteristics, and fertility outcomes of post-thawed rooster semen. Adult Ross broiler breeder roosters (n = 20) were subjected to semen collections twice a week for three weeks. At each collection, semen samples were pooled and allocated into five treatments corresponding to different nano-SL concentrations (control, SL0.5, SL1.0, SL1.5, and SL2.0). Sperm parameters, including motility (collected using a computer-assisted sperm analysis system), plasma membrane and acrosome integrities, and mitochondrial activity were assessed. Sperm malondialdehyde (MDA) and antioxidant activities (total antioxidant capacity (TAC); superoxide dismutase (SOD); glutathione peroxidase (GPx)) were evaluated. The fertility and hatchability obtained with frozen–thawed rooster semen supplemented with the optimum nano-SL concentration were assessed after artificial insemination. The results showed that the addition of 1% nano-SL into the extender led to a higher semen motility in roosters, improved plasma membrane and acrosome integrities, and higher mitochondrial activity of post-thawed rooster semen in comparison to controls (p < 0.05). The MDA levels in the SL0.5 and SL1.0 groups were lower than the other groups (p < 0.05). TAC activities in SL0.5, SL1.0, and SL1.5 groups were significantly higher than those in the other groups (p < 0.05). It was observed that the concentration of SOD was higher in the SL1.0 group than in the other groups (p < 0.05). The activity of GPx was not influenced in any of the cases (p > 0.05). Moreover, the percentages of fertility and hatchability in the SL1.0 group were higher (56.36% and 58.06%) than those in the control group (42.72% and 40.43%). In summary, the addition of nano-SL to the extenders enhanced the post-thawed semen quality and fertility of roosters by reducing the level of oxidative stress. The optimum nano-SL concentration was 1.0%. These results may be beneficial for improving the efficacy of semen cryopreservation procedures in poultry breeding.

Poloxamer 188 and hydroxyethyl starch have a cryoprotective synergic effect improving post-thawing quality and fertility of rooster spermatozoa

Poloxamer and hydroxyethyl starch have cytoprotective effects. In the present study, effectiveness was evaluated of these compounds as a cryoprotectant for rooster semen. In Experiment 1 (E1), poloxamer 188 (1%, P188), poloxamer 407 (1%, P407), and control groups were compared after sperm cryopreservation. Experiment 2 (E2) was conducted with 3%, 5%, and 7% of hydroxyethyl starch (H3, H5, H7), also combined with P188 (H3P188, H5P188, H7P188), based on results from E1. Sperm motility was assessed using CASA, abnormal forms and hypo-osmotic swelling (HOS) were evaluated using microscopy, and viability, apoptotic-like changes, and mitochondrial activity were determined using flow cytometry. In E2, there were assessments of fertility and hatching capacity. Results from E1 indicated total and progressive motility, velocity, membrane functionality, viability, and mitochondrial activity were greater with inclusion of P188 in semen extender, with less apoptotic-like changes (P < 0.05). In E2, HES inclusion in semen extender improved total motility, membrane functionality, and mitochondrial activity (P < 0.05), especially H5, which also markedly increased sperm viability and decreased apoptotic-like changes. The combination of P188 with HES increased sperm quality overall, with inclusion of H5P188 resulting in increases of progressive motility and VSL (P < 0.05). The H5 inclusion also increased proportion of fertilized eggs (P < 0.05). Furthermore, the combination of HES and P188 increased proportions of fertilized and hatched eggs compared with the control, with inclusion of H5P188 having the greatest effects. In conclusion, supplementation of semen extender with H5P188 increases post-thawing quality and fertility of rooster sperm, being a safe and effective method for the poultry industry.

Cryopreservation of Avian Semen

Cryopreservation protocols for semen exist for bird species used in animal production, fancy and hobby species, and wild bird species. Freezing of bird oocytes or embryos is not possible. Cryopreservation of avian semen is used for preserving (genetic diversity of) endangered species or breeds. Freezing semen can also be used in the breeding industry for maintaining breeding lines, as a cost-effective alternative to holding live birds. Success and efficiency of cryopreservation of bird semen differs among species and breeds or selection lines. This chapter describes important variables of methods for collecting, diluting, cold storage, and freezing and thawing of bird semen, notably the medium composition, cryoprotectant used and its concentration, cooling rate, freezing method, and warming method. Media and methods are described for freezing semen using either glycerol or DMA as cryoprotectant, which both are known in chicken and a number of other bird species to render adequate post-thaw fertility rates.

Effect of crocin and naringenin supplementation in cryopreservation medium on post-thaw rooster sperm quality and expression of apoptosis associated genes

The aim of our study was to examine the effects of crocin (0.5 (C0.5), 1 (C1) and 1.5 (C1.5) mM) and naringenin (50 (N50), 100 (N100) and 150 (N150) μM) in cryopreservation extender for freezing rooster semen. Sperm motility, viability, abnormalities, membrane functionality, active mitochondria, apoptosis status, lipid peroxidation (LP), GPX, SOD, TAC, the mRNA expression of pro-apoptotic (CASPASE 3) and anti-apoptotic (Bcl-2) genes, fertile eggs, hatched eggs and hatching rate were investigated following freeze-thawing. C1 and N100 resulted in higher (P < 0.05) total motility and progressive motility in comparison to the control group. The C1 and N100 groups improved viability, membrane functionality and reduced lipid peroxidation. We found higher values for active mitochondria with C1 and N100 compared to control group. The C1 and N100 groups showed lower percentages of early apoptosis when compared with control group. Also, C1 and N100 had higher TAC, compared to the control group. The mRNA expressions of BCL-2 in the C1 and N100 groups were significantly higher than that of other treatments. The expression of CASPASES 3 was significantly reduced in C1 and N100 group (P < 0.05) when compared to control group. Significantly higher percentages of fertile eggs, hatched eggs and hatching rate were observed in C1 and N100 compared to the control group. In conclusion, crocin at 1 mM and naringenin at 100 μM seem to improve the post-thawing rooster semen quality, fertility and could protect the sperm by reducing the pro-apoptotic (CASPASE 3) and increasing anti-apoptotic (Bcl-2) genes.

Does alpha-lipoic acid-loaded nanostructured lipid carriers improve post-thawed sperm quality and ameliorate apoptosis-related genes of rooster sperm?

Oxidative stress could be prevented by antioxidant-loaded nanoparticles. The purpose of this study was to assess the effects of 10 (A10), 20 (A20), 30 (A30), 40 (A40), and 50 (A50) μM alpha-lipoic acid and alpha-lipoic acid nanostructured lipid carriers (ALN) at 10 (ALN10), 20 (ALN20), 30 (ALN30), 40 (ALN40), and 50 (ALN50) μM on post-thawed sperm quality, fertility, and apoptosis-related genes of rooster sperm. The extender supplemented with ALN30 led to higher total and progressive motility, straight-line velocity, and linearity in comparison to the control group. The ALN30 resulted in higher percentage of mitochondria activity and glutathione peroxidase level compared with control (P < 0.05). The extender supplemented with ALN30 led to lower percentage of apoptotic sperm, when compared with the control. CASPASE 3 expression in ALN30 was lower (P < 0.05) than the other groups. The results showed that BCL-2 mRNA expression of sperm was significantly (P < 0.05) higher in ALN30 compared with the other groups (P < 0.05). Higher percentages of fertility and hatchability rates were observed in ALN30 group. The results indicate that ALN30 could be regarded as a novel potential cryoprotectant for the cryopreservation of rooster semen. Therefore, nanostructured lipid carriers improve not only the active compound (such as alpha-lipoic acid) of biomedical applicability but also the potential for industrial application in sperm cryopreservation.

Poloxamer 188 exerts a cryoprotective effect on rooster sperm and allows decreasing glycerol concentration in the freezing extender

Glycerol is the most widely used cryoprotectant for rooster sperm because it declines the mechanical damage to sperm during the freezing process. Despite its high molecular weight and viscosity, which may be cytotoxic, glycerol can cause damage to cells during the cryopreservation process, resulting in less fertility. Poloxamer 188 (P188) is an embryo cryopreservation supplement effective in many species and also for cell lines and plant cells. We tested the suitability of P188 in the cryopreservation of rooster sperm, considering post-thawing motility, abnormalities, membrane functionality (hypo-osmotic swelling test), mitochondrial activity, viability, apoptosis status, reactive oxygen species production, and ATP content after thawing and the fertility and hatchability after AI. We carried out a factorial experiment with glycerol concentrations of 2% glycerol (G2) and 8% glycerol (G8) and P188 concentrations of 0% (P0), 0.1% (P0.1), 0.5% (P0.5), and 1% (P1) as fixed effects, with replicate (seven) as a random effect. Interactions between glycerol and P188 were found, with G2P1 yielding higher quality and fertility. G8P0.5 yielded better in most parameters, however, not reaching G2P1. G2P1 showed significantly higher results for total and progressive motility, kinetic parameters (average path velocity, straight-line velocity, and linearity), membrane functionality, viability, mitochondrial activity, and ATP content and lower apoptosis, dead sperm, and reactive oxygen species production. G2P1 resulted in the highest percentages of fertilized and hatched eggs, with no effects in the hatched eggs ratio. Interestingly, G2 was less efficient in many parameters than G8 when combined with P0 and P0.1, being equivalent to G8 with P0.5 and superior to any G8 treatment as G2P1. In conclusion, P188 could improve rooster semen cryopreservation and allow reduction of glycerol in extenders, with a consequent impact in the poultry industry.

Effect of quercetin loaded liposomes or nanostructured lipid carrier (NLC) on post-thawed sperm quality and fertility of rooster sperm

The aim of this study was to investigate the effects of 10, 15 and 20 μM quercetin, alone or loaded in nanoliposomes or in nanostructured lipid carrier (NLC) on sperm rooster cryopreservation and fertility performance. Sperm motility, viability, abnormalities, membrane integrity, mitochondrial activity, apoptosis status, lipid peroxidation (LP), GPX, SOD, TAC and fertility and hatchability rate were investigated after freeze-thawing. A significantly higher percentage (P < 0.05) of sperm total motility was obtained in sperm cryopreserved with 15 μM quercetin loaded NLC compared to diluent with 10 and 20 μM quercetin and to 10, 15 and 20 μM quercetin loaded nanoliposomes, 20 μM quercetin loaded NLC and control group. Also, 15 μM quercetin loaded NLC was significantly higher in progressive motility, VSL, VAP and VCL parameters compared to control group. The percentage of viability, membrane integrity, mitochondria activity, TAC, and GPx increased in semen exposed to 15 μM quercetin loaded NLC group. Likewise, the lowest level (P < 0.05) of malondialdehyde (MDA) was acquired in samples treated with 15 μM quercetin and quercetin loaded NLC group in comparison to the control group. Abnormal form, SOD, and early apoptosis were not (P > 0.05) affected by different levels of quercetin. Fertility and hatchability rate showed higher levels in 15 μM quercetin and quercetin loaded NLC group compared with control group. In conclusion, it seems that quercetin loaded NLC enhanced the antioxidant effect of quercetin by improving post-thawed sperm quality and fertility of rooster sperm.

Effect of astaxanthin nanoparticles in protecting the post-thawing quality of rooster sperm challenged by cadmium administration

The protective role of astaxanthin nanoparticles (Ast NPs, 25 mg/kg p.o) against cadmium (Cd, 1 mg/100 g b.w. SC), a known inductor of lipid peroxidation and changes in the antioxidant defense system in the Ross 308 breeder roosters sperm, was examined. Sperm motility (computer-assisted sperm motility analysis), membrane integrity (hypoosmotic swelling test), viability, total abnormality, and enzymatic parameters were assessed after thawing. The testis/body weight (mg/kg) ratio and HE staining results of testis were also performed. The obtained results showed that Cd induced detrimental effects on testis and sperm, while Cd treated by Ast NPs (Cd Ast) diminished this change compared to the Cd group. Cd-treated group resulted in significantly (P < 0.05) lowest total (37.29 ± 2.46) and progressive (5.84 ± 0.47) motility and decreased antioxidant enzyme activity (CAT, TAC, and GPx), as well as producing a significant (P < 0.05) decrease in testis weight (mg) compared to the control group. Treatment with Ast NPs (Ast NPs + Cd) had reversed Cd-induced changes in the antioxidant defense system and significantly prevented Cd-induced testis damage. In conclusion, the results of our work suggest that Ast NPs at 25 mg/kg act as a potent antioxidant in protecting rooster testes against oxidative stress induced by Cd.

Improving the quality of rooster semen frozen in straws by screening the glycerol concentration and freezing rate

1. This study examined different glycerol concentrations (GC) and freezing rates to improve the quality of rooster spermatozoa frozen in straws, and to determine the effect of varying GC on post-thawed spermatozoa quality, as evaluated by fertility and hatchability.2.The experiment included two tests. In test 1, rooster semen straws containing 2, 4, 6, 8 and 11% glycerol were put in a rack (nine tiers with a 1 cm interval between every two tiers, 1 to 9 cm above liquid nitrogen (LN) source), and gradually frozen. The semen straws located in different tiers experienced different temperatures and freezing rates. The straws were then thawed and live sperm numbers determined. In test 2, rooster semen straws containing 2, 4, 6, 8 and 11% glycerol were put on optimal tiers (identified in test 1) for freezing, and stored at -196°C. Hens were inseminated with the frozen semen (post-thawed and glycerol removed, about 4.0 × 10⁸ sperm per hen), and eggs incubated.3. The numbers of live sperm in the 11% glycerol group was higher than that in 2, 4 or 6% glycerol group (P < 0.05) for the semen straws on tiers 1 to 9, while that on tiers 1 to 5 was lower than that on tier 6 to 8 (P < 0.05). GC, freezing rate and the interaction between GC and freezing rate had a significant effect on live sperm numbers (P < 0.01). The highest fertility was in the 6% glycerol group and occurred on day 5 after insemination. The lowest fertility occurred in the 2% glycerol group on day 10 after insemination.4. The optimal combination was 11% glycerol in straws located 6 cm above the LN surface (on tier 6). The 6% glycerol group achieved the highest fertility (77.6%), which surpassed that reported in recent years.

Does fennel extract ameliorate oxidative stress frozen-thawed ram sperm?

The aim of this study was to evaluate the quality of ram semen after cryopreservation with different levels of fennel (Foeniculum vulgare) extract (0 (F0), 5 (F5), 10 (F10) and 15 (F15) mg/L) and sperm concentrations (200 (C200) and 400 (C400) × 10⁶ sperm/mL) in a soy lecithin (SL)-based extender. Twenty ejaculates were collected from four ghezel rams and diluted with eight sperm concentrations/fennel combinations: F0C200, F5C200, F10C200, F15C200, F0C400, F5C400, F10C400 and F15C400. Sperm motility, abnormality, plasma membrane, viability, mitochondrial activity, lipid peroxidation (LPO), mitochondrial activity and apoptotic changes were evaluated after freeze-thawing process. It was observed that F10C400 significantly improved total and progressive motility, VSL, membrane integrity of post-thawed ram sperm. MDA level was lower in F5C200 and F10C400 compared to other treatments. The higher percentage of live sperm and the lower percentage of apoptotic sperm were obtained in F10C200 compared to F0C200, F5C200 F15C400, F0C400, F5C400 and F15C400. Extender F10C200 resulted in the highest mitochondria activity compared to the rest of the extenders except F10C400. We conclude that a combination of 10 mg/mL fennel (Foeniculum vulgare) extract and sperm concentration of 200 × 10⁶ sperm/mL can improve the ram semen quality cryopreserved in a soybean lecithin based extender.