جستجوی مقالات مرتبط با کلیدواژه « انجماد » در نشریات گروه « علوم دام »

Sperm cryopreservation is a highly effective technique utilized in reproductive procedures, particularly in artificial insemination, as it enables the transfer of superior genes to the subsequent generation of animals. However, the exposure of sperm cells to low temperatures during the freezing process can have detrimental effects on their integrity, morphology, and viability (Gangwar et al., 2020). To counteract these negative impacts, cryoprotectants are added to the sperm extender. The primary purpose of incorporating cryoprotectants is to fulfill the energy requirements of the sperm, shield them from the adverse consequences of temperature fluctuations, mitigate the physical and chemical stresses associated with cooling, freezing, and thawing, and create an environment conducive to enhancing sperm survival (Barbas and Mascarenhas, 2009). In recent years, plant-based extenders have emerged as a viable alternative to animal-based extenders for semen preservation in various species. Coconut milk, in particular, has garnered attention due to its rich composition of fatty acids (including polyunsaturated fatty acids), amino acids, sugars, antioxidants, vitamins, and minerals. These components not only provide essential nutrients for maintaining cell function but also serve as a suitable medium for sperm extension and culture (dos Reis et al., 2023; Vasconcelos et al., 2009; Yong et al., 2009). Consequently, this research aims to explore the impact of coconut milk on the quality of ram sperm following cryopreservation. Twice a week, semen samples were obtained from five Lori-Bakhtiari rams using an artificial vagina. The collected semen from these five rams was then combined and divided into six different treatments. These treatments consisted of five variations with varying levels of coconut milk (5%, 10%, 15%, 20%, and 25%) and one treatment with egg yolk (15%). Various parameters such as sperm velocity, membrane integrity and activity, morphology, lipid peroxidation rate, and sperm DNA fragmentation were assessed both before and after the process of cryopreservation. The obtained data was subsequently analyzed using the SAS statistical software. Prior to cryopreservation, the results indicated that, with the exception of the BCF parameter, there were no disparities in the various aspects of sperm kinetics, viability, functionality, and morphology. However, a notable decline in sperm motility parameters was observed after thawing across all treatments. This detrimental impact following the freezing process was more pronounced (P<0.05) when using the extender containing coconut milk compared to the extender containing egg yolk. Consequently, in terms of other motility parameters, the egg yolk treatment exhibited significantly higher values (P<0.05) than the other treatments, except for VCL (94.36±10.41%) and BCF (5.83±0.70 Hz). The findings of Wojtusik et al. (2018) were in line with the results obtained in this study. It was observed that when coconut water and coconut milk were used as substitutes for egg yolk in rhinoceros sperm extenders, there was a decrease in both sperm motility and viability. Similarly, the use of powdered coconut water as an extender for cryopreservation of cat sperm resulted in a significant reduction in sperm movement quality compared to a tris extender (de Sousa Barbosa et al. 2020). Furthermore, when comparing different alternatives to egg yolk in the extender of rhinoceros sperm, such as soy lecithin (1 and 2%), coconut water (20%), and coconut milk (20%), it was found that the extenders containing coconut milk or water led to a loss of sperm mobility and viability. However, the extenders containing soy lecithin showed more promise as substitutes for egg yolk, as they maintained sperm viability, morphology, and acrosome integrity better than coconut milk and water (Wojtusik et al., 2018). In contrast to the findings of this investigation, the utilization of extenders comprising powdered coconut water for the cryopreservation of sperm in various animal species, including dogs, boars, horses, goats, and fish, resulted in well-preserved sperm morphological and motility parameters following the freeze-thaw process. Furthermore, studies have demonstrated that freezing goat sperm with coconut milk, bull sperm with coconut oil, and equine and boar sperm with coconut water led to enhanced sperm viability and quality compared to control groups. The ineffectiveness of the extender may be attributed to the presence of salts and ions, such as calcium, potassium, and sodium, in coconut water, which could potentially interact with the channel proteins of the sperm cell plasma membrane. It is important to note that the precise mechanism by which coconut products in the extender maintain sperm characteristics remains unknown. Previous research by Toniolli et al. (1996) suggested that coconut water may serve as a protective agent for sperm due to its content of 3-indoleacetic acid. Furthermore, the replacement of glycerol with dimethylformamide in the boar sperm extender resulted in better preservation of sperm quality after the freezing and thawing process compared to other treatments (Silva et al. 2015). This suggests that each ingredient present in an extender could have a significant impact on enhancing extender efficiency. It is worth noting that coconut milk contains high levels of polyunsaturated fatty acids, which can make sperm more vulnerable to oxidative stress (dos Reis et al., 2023; Vasconcelos et al., 2009). However, no significant differences were observed in the lipid peroxidation indicator and the DNA fragmentation index among the various extenders used in this study. This could indicate that the extenders had similar antioxidant properties. The variations in the reported findings may be attributed to differences in the combinations and quantities of products used in the extenders, the type of base extender employed, variations in semen combinations and the sensitivity of sperm in different animal species, or discrepancies in the coconut combinations utilized (dos Reis et al., 2023). This research suggests that substituting egg yolk with coconut milk entirely in a ram sperm extender does not mitigate the negative consequences of cryopreservation. Additional investigations are necessary to determine the specific composition of the extender incorporating coconut-based ingredients for the cryopreservation of ram sperm.

Dietary supplementation of trace minerals (zinc, copper and manganese) has positive effects on various aspects of reproductive performance of farm animals and it has a strong antioxidant effect on sperm function. Also, feeding with trace minerals affects the functional structure of sperm cells and increases the quality of sperm for cryopreservation because it may lead to cell damage, production of reactive oxygen species and reducing the antioxidant capacity of seminal plasma. The objective of this study was to investigate whether dietary supplementation of zinc, copper and manganese affected on sperm motion characteristics, percentage of viability, sperm membrane integrity after thawing, and flow cytometry tests including apoptosis, hydrogen peroxide and molecular oxygen. Ten mature Afshari rams were all fed a nutritionally adequate diet for 70 days, from the end of September to the beginning of December. Half of the rams were randomly designated to receive dietary supplementation with a sulfate source of zinc, copper and manganese once daily for 70 days, starting 1 week after the study began. All ejaculates were diluted with a Tris-based cryoprotective extender. The extended semen was subsequently loaded into 0. 5 mL plastic straws and then they were frozen by the bio-freezer machine. One week after freezing, three straws of each ram were thawed and evaluated for sperm motion characteristics by computer-assisted-semen-analysis system, hypoosmotic swelling test and live sperm percentage. In addition, we examined hydrogen peroxide, molecular oxygen and apoptosis in frozen sperm. Proc Mixed was used for analysis of repeated measures data. Motion characteristics, percentage of sperm viability and sperm membrane integrity after thawing in the Supplemented group was relatively stable and significantly higher than in the Control group from day 28 onwards (P<0/05). At the end of this research, the levels of hydrogen peroxide, molecular oxygen, early apoptosis, late apoptosis and necrosis in the control group were significantly higher than the Supplemented group (P<0/05). The average number of live sperm in the Supplement group increased slightly at the end of the research period outside the breeding season, but it was not significant compared to the beginning of the period, but this rate at the end of the period was significantly higher than that of the Control group (P<0/05). The results showed that the simultaneous supplementation of zinc, copper and manganese elements, even after the reproductive season, can have beneficial effects on the quality and freezing ability of sperm after thawing and prevent the creation of reactive oxygen species and the occurrence of apoptosis.

The need for artificial insemination in the ewe is to access fresh and frozen sperm. Cryopreservation is a suitable method for long-term storage of semen and sperm, but may cause a minor irreversible damage to the sperm cell, especially its membrane region (Khorramabadi et al., 2017). The oxidation of fatty acids leads to the production of free oxygen radicals (ROS). These radicals are necessary in normal conditions for certain physiological activities and sperm processes, but excessive production of ROS in the sperm can reduce membrane fluidity, DNA fracture, damage to proteins, and ultimately reduced sperm motility and fertility. (Bakhshayesh et al., 2017). Silymarin, the scientific name of Silbum marianum, is the English name Milk Thistle and is a potent inhibitor of oxidative stress as a potent antioxidant. Due to the nature of its friend fat, silymarin is firmly attached to the plasmid membrane compounds, thus preventing fracture and its collapse by increasing membrane strength. Increasing the amount of active oxygen species and lipid peroxidation disrupts mitochondrial membrane, decreases ATP and damage to sperm acesomes, which ultimately reduces the progression of sperm motility. (Kvasnikova et al., 2003). The mechanism of action of salimarin is through stimulation of the ribosomal RNA and protects the membrane from oxidative damage. They also stated that silymarin stimulates the activity of the antioxidant enzymes of superoxide dismutase (SOD) and glutathione peroxidase (Wellington and Jarvis, 2001) . Silymarin improves the sperm motility and survival, sperm abnormalities, and preservation of the sperm membrane after freezing-thawing. Improvement of semen quality in both freezing and cooling is due to the strong silicomain antioxidant capacity (Fakorzai et al., 2008; Longpyram et al., 2013). .

Regarding the anti-oxidant effects of silymarin, this study aimed to investigate the effect of silymarin on storage of ram sperm.

In this research, four rams of pure ghee were used 2-3 years old and each ram was 6 times sperm. Sperm was performed twice a week by artificial vagina. After the sample was transferred to the laboratory, a series of preliminary evaluations including sample size, sample color, wave motion, total mobility, in-situ motion, progressive motion and live weight, and abnormal sperm and density were performed. If standards were met, Necessary (scaling over 2.5 billion sperm and progressive movement above 70%) dilution was performed with treatments. The diluents were prepared prior to sampling and placed in a bin Marie temperature of 37 ° C. Tris-based diluent was used to contain 2.73 g of tries, 1.4 g of fructose, 1 g of citric acid and 100 mg streptomycin in 100 ml sterile distilled water. To prepare the diluent, 73% of the prepared solution will be mixed with 20% egg yolk and 7% glycerol. In order to dilute the sprays from trace based diluent, egg yolk, semen collected with diluent without antioxidants (control) and silymarin 5 and 10 μg / ml mix After cooling for 90 minutes in the refrigerator and reaching 5 ° C, it was placed in 4 cm above the liquid nitrogen for 8-10 minutes and then immersed in liquid nitrogen. The post-mortem examinations of sperm quality properties included liveliness, total motion, progressive motion, integrity of the plasma membrane (tests) on days 0, 15, 30 of the experiment.

According to the results of the experiment, the diluents containing the levels of silymarin significantly increased the total motion, progressive, live survival of ram sperm after the freeze-thawing process compared to the control group Were opened. Addition of different concentrations of silymarin was 5 and 10 μg with mean of 74.45% and 67.33%, respectively, compared to the control group, significantly increased the total sperm motility with mean of 68.07 and 60.95%, significantly Progressive motility of frozen ram sperm were frozen (p <0.01). According to the results, the in situ movement in the control group (5.92 ± 0.92) was lower than that of the 5 and 10 μg silymarin (6.38 ± 0.92) and (8.9 ± 0.92) respectively In the least amount.

Application of silymarin as an antioxidant in the ram sperm diluent system reduces oxidative damage and improves sperm quality properties such as mobility, viability and the health of acrosome and plasma membrane during freezing process. Was opened. Adding 5 μg of silymarin to diluted ram minus 10 μg and control group reduced fat peroxidation and also improved the structure and performance of sperm during storage.

The purpose of this study was to investgate resveratrol nano-protected antioxidant on rooster sperm. In this study, resveratrol was used in the forms of nano-protected (liposome and NLC) and plain in the semen extender. Immediately after the semen collection and for primary evaluations, for eliminating of individual effects the semen collected from 15 roosterswere pooled and added to the extender. Extending was done at 37 °C at a dilution ratio of 1:20. Different concentarions of resveratrol (20, 40 or 60 μM) were added to the extender in three forms of plain, NLC, and liposome. After diluting the semen, gradual cooling was carried out for 3 h at 4 °C. After the cooling process, the kinetic parameters (CASA), membrane integrity (HOST), viability, lipid peroxidation (MDA), abnormal sperm, were evaluated. The results at 24 and 48 hours at a temperature of 4°C indicate that the use of 40 μM resveratrol, resveratrol loaded in the liposome, and resveratrol loaded in the NLC improved the motility, progressive sperm motility, viability, and membrane integrity compared to the control group. The results of this experiment indicated that 40 μM resveratrol, resveratrol loaded in liposome and resveratrol loaded in NLC improved most of the evaluated parameters.

This study was designed to evaluate the effects of encapsulated reduced glutathione added to extender on the quality of bull sperm after freezing and thawing process. Extender contains lecithin nanoliposomes supplemented with different concentrations of glutathione (0, 1, 2.5 and 5 Mm concentration). The supplemented nanoliposomes with glutathione were prepared by thin-film preparation method.  The particle size decreased to nanometer by sonication. 40 ejaculations were collected from 6 Holstein bulls and frozen for 6 weeks. Evaluated characteristics after freezing and thawing process were kinetic parameters (CASA), membrane activity (HOST), membrane integrity (eosin-nigrosin) and morphology of sperm ( Hancock's solution). Results showed that level 1 mM significantly increased the total and progressive motility (47.5±1.7, 32.7±2 %).  Although, there was no significant difference with level 2.5 mM glutathione (45.0±1.7, 26.2±2 %). Also, the concentration of 2.5 mM showed the highest value of cell membrane integrity and cell membrane functionality but did not differ with the concentration of 1mM. However, supplementation of nanoliposomes with 5 mM glutathione reduced the quality of post-thaw sperm. Thus, level 1 M encapsulated glutathione can provide better protection compare to the other level of that for bull sperm.

This study was designed to evaluate the effects of encapsulated reduced glutathione added to extender on the quality of bull sperm after freezing and thawing process. Extender contains lecithin nanoliposomes supplemented with different concentrations of glutathione (0, 1, 2.5 and 5 Mm concentration). The supplemented nanoliposomes with glutathione were prepared by thin-film preparation method.  The particle size decreased to nanometer by sonication. 40 ejaculations were collected from 6 Holstein bulls and frozen for 6 weeks. Evaluated characteristics after freezing and thawing process were kinetic parameters (CASA), membrane activity (HOST), membrane integrity (eosin-nigrosin) and morphology of sperm ( Hancock's solution). Results showed that level 1 mM significantly increased the total and progressive motility (47.5±1.7, 32.7±2 %).  Although, there was no significant difference with level 2.5 mM glutathione (45.0±1.7, 26.2±2 %). Also, the concentration of 2.5 mM showed the highest value of cell membrane integrity and cell membrane functionality but did not differ with the concentration of 1mM. However, supplementation of nanoliposomes with 5 mM glutathione reduced the quality of post-thaw sperm. Thus, level 1 M encapsulated glutathione can provide better protection compare to the other level of that for bull sperm.

The effect of feeding L-carnitine during pre-puberty on the quality parameters of fresh and frozen-thawed semen by using 12 Ross broiler breeder males (12 weeks) for 18 weeks, in a completely randomized design with three treatments (0, 250 and 500 mg / kg of L-carnitine in the diet) and four replications was performed. From the age of 26 to 29 weeks, semen collection was performed using abdominal massage. The sperms taken each time after dilution (with Beltsville diluent) were divided into two parts, one section was frozen and the other part was immediately examined. Motility (total and forward), viability, morphology, membrane functionality and lipid peroxidation parameters were evaluated. In fresh sperm, the correlation between L-carnitine and abnormalities was negative linear, and with viability was positive linear (P<0.05). Quadratic analysis was significant in forward Motility and MDA concentration (P<0.05). Birds that use diets containing L-carnitine, In terms of forward motility, viability, morphology and MDA concentrations in fresh sperm, And these traits, with the total motility and integrity of the plasma membrane of frozen sperm, were higher in comparison to the control group (P<0.05). Also, in the sperm after frozen-thawed, the correlation between L-carnitine and Motility (total and forward), viability and membrane integrity were positive linear (P<0.05), and the correlation between L-carnitine and MDA concentration was negative linear (P<0.05). The correlation between L-carnitine and Motility (total and forward), membrane integrity and MDA concentration were quadratic (P<0.05). According to the results, Dietary L-carnitine supplementation in pre-puberty improves the qualitative traits of sperm before and after freezing in the breeder broilers.

This experiment was designed to evaluate the protective effect of nano-hydroxyapatite against freezing damages on spermatozoa using five rams. Ejaculates (N=30) were collected with three-day intervals between sessions for six times. Ejaculates were pooled and split into 12 parts at each session. The amount of 0.01, 0.02, 0.05 or 0.1% nano-hydroxyapatite and 3, 5 or 7% glycerol were added. Samples were frozen and stored for two weeks. After that two straws from each treatment for each replication (totally 144 straws) were thawed and incubated at 37 ° C for 6 h. Sperm motility, viability, membrane integrity and acrosome integrity were evaluated at 0, 3 and 6 h after thawing. Results showed that there was no interaction between nano-hydroxyapatite, glycerol and incubation time (P>0.05). Sperm viability and acrosome integrity were not affected by different levels of nano-hydroxyapatite particles (P>0.05). There was no difference between the level of 0.01 and 0.1% nano-hydroxyapatite particles on the total (21.8 and 21.5%, respectively) and progressive sperm motility (17.8 and 17.7 %, respectively; P>0.05). Total and progressive sperm motility was the highest (24.8 and 21.0%, respectively) in the level of 0.02% nano-hydroxyapatite particles (P<0.05). Membrane integrity was higher in the level of 0.02% nano-hydroxyapatite particles (52.7%) than other levels (P<0.05). Therefore, the addition of 0.02% nano-hydroxyapatite particles to the ram semen extender improved the quality of frozen spermatozoa.

To examine the effect of glycyrrhizic acid on lipid peroxidation and vital parameters of Holstein bull sperm after freeze-thawing process, semen samples were collected from four mature Holstein bulls twice a week using artificial vagina. Ejaculates were pooled in order to eliminate the individual effects of bull. Semen samples were divided into four equal groups (8 reps) including Zero (control), 20, 30 and 40 mg/ml of glycyrrhizic acid along with diluents based on egg yolk-citrate. Following cooling and equilibration stage, semen samples were stored in nitrogen tank for 30 days. After thawing procedure, level of malondialdehyde in sperm samples were measured by ELISA. Also, membrane integrity, motility and viability of sperm were examined. Statistical analysis was carried out using one-way ANOVA and post-hoc Tukey tests (p<0.05). According to the results, membrane integrity, motility and viability of sperm samples treated with concentration of 20, 30 and 40 mg/ml glycyrrhizic acid dose dependent manner significantly increased and level of malondialdehyde dose dependent manner significantly decreased ccompared to control groups (p<0.05). Therefore, use of glycyrrhizic acid in bull semen diluent can improve sperm vital parameters and decreases lipid peroxidation of sperm after freeze-thawing process.

Artificial insemination is a reproductive technology that uses the best male breeders. Successful artificial insemination is affected by several factors, one of the most important of which is the availability of fertile sperm after the freezing-thawing process. The purpose of this study was to investigate the effect of different concentrations of naringenin after the freezing process. Sperm collection was performed twice a week using abdominal masage. After adding the diluent to the semen samples, the samples were placed in the refrigerator at a temperature of 4°C for equilibration. Samples were then transferred to freezing straws and exposed to nitrogen vapor, then stored in a tank containing liquid nitrogen. After thawing, several parameters containing motility, viability, abnormality, membrane integrity, MDA production, SOD and GPX enzymes and total antioxidant capacity were evaluated. The results indicate that the total and progressive cavity in 100 μM naringenin treatment significantly increased compared to control treatment. The percentage of sperm with morphological abnormalities in different concentrations of naringenin did not differ significantly (p<0.05). The viability and membrane integrity of the sperm cells at 100 μm concentration increased significantly compared to the control group. The results of this experiment indicate that 100 μm naringenin treatment increased glutathione peroxidase and total antioxidant capacity and reduced MDA levels compared to control group. Based on the results of this study, naringenin at 100 μm in a diluent medium improves rooster sperm quality after freeze-thawing.

The highest damage to the sperm is caused by oxidative stress due to the production of reactive oxygen species (ROS). Semen cryopreservation causes some structural, biochemical and functional changes, which leads to various problems in sperm transport, survival and fertility rate in domestic animals. Also, sperm metabolism produces ROS, which is potentially harmful to the sperm plasma membrane integrity loss of motility .High concentrations of ROS have negative effects on sperm quality and increased degradation of DNA, lipid peroxidation and oxidative stress which inhibits sperm motility and changes in sperm infrastructure and finally the reduction of fertility.
Seminal plasma contains enzymes such as superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) which have an important role in the inhibition of the deleterious effects of ROS. Lipid peroxidation may be due to lack of coordination between SOD, GPX, and CAT in seminal plasma or deficiency of total antioxidant capacity of the cell. Ellagic acid is a polyphenol compound that can be found in green tea and other natural resources such as pomegranate, strawberry, raspberry, walnut and eucalyptus bark. Ellagic acid showed antioxidant and anti-apoptotic effects, it can delay or prevent cellular oxidation; ultimately reduce oxidative stress.Ellagic acid increases the activity of enzymes SOD, CAT and GPx by preventing free radical attack to cells. This research was conducted to evaluate the antioxidant effect of different levels of Elligic acid on microscopic, biochemical parameters, antioxidant enzyme activities and total antioxidant capacity of ram semen after freezing-thawing process.
Five Ghezel rams were used. Semen samples were collected twice a week using artificial vagina. In order to remove individual effects, the semen samples were pooled together. Different levels of ellagic acid (0.25, 0.5, 1, 1.5 mM) were added in diluent of tris-lecithin based. After processing and freezing, the samples were stored in liquid nitrogen until the time of evaluation. After thawing of semen samples, sperm motility parameters were evaluated using CASA system, viability by with Eosin-nigrosin staining, membrane integrity with a solution of hypo-osmotic, sperm abnormalities using a solution of Hancock, lipid peroxidation by measuring malondialdehyde and the seminal plasma antioxidant enzymes of glutathione peroxidase, superoxide dismutase and total antioxidant capacity using the RANDOX Laboratories kit. The data were analyzed with SAS (9.1.3) software using GLM procedures.
The results showed that the levels of 0.25, 0.5, 1 and 1.5 mM ellagic acid improved survival and total motility parameters (P The findings of this study showed that the diluent containing 0.5 mM ellagic acid significantly improved sperm parameters compared to other levels, after freezing-thawing process.

The most worthwhile technique for preservation and management of bird genetic resources is semen cryopreservation, which has been studied in domestic birds like chicken. Despite years of intensive investigations, still more work should be done in order to perform successful cryopreservation of poultry sperm. The lower quality of frozen-thawed poultry sperm and consequently the poor fertilization rates compared to mammalian species are due to the exceptional morphological properties of poultry sperm, which cause freeze damages because of their vulnerable structure to low temperatures. During sperm cryopreservation, it is exposed to cold and osmotic shock, and resulted in increasing oxidation due to raise in oxidative reactions. It reduces sperm motility, viability, and ultimately reduces fertility. Oxidative stress occurs when oxidants are more potent than antioxidants. Hence, increased production of reactive oxygen species (ROS) caused by oxidative stress leads to lipid peroxidation (LPO), apoptosis, and DNA damage. Generally, the most important effect of lipid peroxidation on cells is the disruption of membrane structure and function. Plasma membrane damage is considered as one of the reasons for decreasing motility and fertility of rooster sperm. The aim of this study was to investigate the effects of different levels of curcumin antioxidants (0, 100, 200 and 300 μM) in Beltsville modified diluents for the cryopreservation of rooster semen. The present hypothesis was that curcumin antioxidants would be effective during cryopreserving of rooster sperm. Several parameters such as sperm motility, abnormalities, membrane integrity, viability and abnormality were assessed in this study to find the best level of curcumin antioxidants for cryopreservation of rooster sperm.
Material and Semen samples were collected from eight Ross 308 rooster three times a week by massaging along the backbone and abdomen .The criteria in normal quality of sperm was as follows: the volume between 0.2 and 0.6 ml (semen volume was measured visually using a graduated collection tube); the concentration of sperm ≥ 3˟109 sperm/ml (ejaculate concentration was evaluated by haemocytometer); total motility ≥80% and abnormal morphology (Hancock method [17]) ≤ 10%. Then, the semen samples were pooled to remove individual variations and obtain sufficient sperm for analysis. Different levels of curcumin were added to semen samples and followed by freezing. After thawing following sperm parameters were evaluated: total motility (TM, %), progressive motility (PM, %), average path velocity (VAP, μm/s), curvilinear velocity (VCL, μm/s), straight linear velocity (VSL, μm/s), amplitude of lateral head displacement (ALH, μm), beat cross frequency (BCF, Hz), straightness (STR, %), and linearity (LIN, %) using CASA software, viability by Eosin-Nigrosine Staining, membrane integrity by HOST test, and sperm abnormality by Hancock test. .
The freezing extender supplemented with 200 μM of curcumin resulted in higher percentages of total and progressive motilities in comparison with other groups and control group following the freeze-thawing process (P The results of this study showed that adding 200 μM curcumin can have favorable effects on post-thawed rooster sperm motility parameters, viability, plasma membrane integrity, and abnormality.

This study was designed to investigate the effects of various concentrations of egg yolk (5, 10, 15 and 20%) and Lecithin (1, 1.5 and 2%) in the extenders based on tris (with 5% glycerol) on the Marghoz goat spermatozoa after freezing-thawing. Semen samples were collected by an artificial vagina, twice a week from four matured goat.The extender containing semen was frozen in liquid nitrogen and then was stored until using for assessment. Semen was thawed at 37◦C and then motility and progressive motility were assessed by CASA. Membrane integrity and viability,morphology were assessed as well and Malondialdehiyde (MDA) were were assessed as well. The results of this experiment showed that extender containing 15% egg yolk and 1.5% Lecithin significantly improved motility, progressivemotility and viability compare to other levels (P 0.05). It can be concluded that use of 15% egg yolk in animal extender and 1.5% Lecithin in vegetable extender is suitable for cryopreservation of Marghoz goat semen.

In artificial insemination of farm animals, frozen sperm is usually used. Sperm cryopreservation is one of the important methods for maintain and preserve genetic resources, which as one of the methods of assisted reproductive, can maintain the quality of sperm. Since beginning the time of artificial insemination technique, different diluents have been used to maintain and preserve semen in liquid and frozen condition. Extender composition and nature are of great importance in the viability of sperm. To this end, the aim of this research was to evaluate effects of milk, Tris-chicken egg yolk and Tris-turkey egg yolk extenders and different levels of trehalose sugar (0, 80, 100 and 120 mM) on Dalagh ram semen quality after freezing-thawing process.
In this research semen samples were collected from four Dalagh rams in the age of 2-3 years using artificial vagina. Then samples were diluted in different extenders and received different trehalose sugar treatments. Semen samples were aspirated into 0.5 ml straws and cooled to 4°C within 150 min and then frozen in liquid nitrogen. Frozen straws were transferred to a tank containing liquid nitrogen. After thawing spermatozoa quality parameters including percentage of sperm motility, viability, membrane integrity and sperm normality were evaluated. This experiment was carried out in 4×3 factorial arrangement with the use of completely randomized design. Treatments were included different levels of trehalose sugar (0 , 80 , 100 , 120 mM) and different extenders (milk and Tris-chicken egg yolk and Tris-turkey egg yolk). The obtained data from this study were analyzed by ANOVA procedure of Statistical Analysis System SAS (version 9.1). Comparison of data means were performed by Tukey test at the level of %1 error.
The results of this research showed effects different levels of trehalose sugar, on the percentage of sperm motility, viability, membrane integrity and sperm normality were significant (P In general, considering all the indices evaluated for the dilution of Dalagh ram semen, the addition of 120 mM trehalose sugar in Tris-turkey egg yolk extender showed a better response than other treatments after freezing-thawing process.

The aim of this study was to evaluate the effects of α- linolenic and linoleic fatty acids, trehalose and sucrose on quality of Markhoz goat frozen-thawed sperm cells. Semen was collected from 4 mature goats using an artificial vagina, evaluated, pooled and divided into 11 aliquots and extended 1:10 with basic tris diluent containing different fatty acids. The motility, progressive motility, viability, acrosome and membrane integrity of frozen spermatozoa have been evaluated after thawing. The results indicated that α- linolenic was significantly the best diluent, while the linoleic acid decreased significantly the quality of spermatozoa, except membrane integrity. Moreover, the use of trehalose and sucrose in diluents decreased significantly the sperm cells characteristics. In addition, the result presented that α- linolenic acid in combination with trehalose improved significantly the rate of acrosome and membrane integrity, but decreased the motility and progressive motility of frozen-thawed spermatozoa. Moreover, the treatments containing all antioxidants and diluents containing linoleic acid and sugars decreased significantly the rate of assessed parameters. In conclusion, the results in this study indicated that using of 20 mg α-linolenic acid in diluent alone and in combination with trehalose can be suitable for cryopreservation of Markhoz goat sperm cells.

Oxidative stress during freeze-thawing process causes reduction in motility, viability, membrane functions and finally sperm fertility.
the aim of this study was to determine the effect of Origanum Vulgare extract as natural antioxidant on quality cryopreserved ram sperm.
In this study semen was collected from five mature ram twice a week using an artificial vagina and the ejaculates were pooled in order to eliminate the individual effect of rams. Different levels of Origanum Vulgare extracts (0, 100,150 and 250 µL/mL diluent solution) were added to diluent based tris-egg yolk. After cooling, filling and sealing of the samples, they were frozen and with nitrogen vapor and immersed in liquid nitrogen and were stored until evaluation time.
After thawing, results showed that addition of 150 µL/mL of extract increased progressive motility compared to the control groups (P The obtained data showed that inclusion of Origanum Vulgare extract in semen freezing extender improved post thawed motility of ram sperm.

The aim of this research was the collection and freezing of honey bee sperm, Apis mellifera, as a trail and evaluating different semen extenders to improve sperm quality after freeze-thawing process as a first trail in Iran. Semen was collected using artificial insemination device. In this experiment three different extenders including; egg yolk (TEY), buffer and 0.5% soybean lecithin (TSL0.5) and buffer and 2% soybean lecithin (TSL2), were used. Collected semen samples were evaluated using microscope and then were diluted with extenders. Diluted samples were gradually cooled in a refrigerator to 5°C and immediately loaded into straws and then frozen in liquid nitrogen. Data were analyzed using the GENMOD procedure of SAS software and results were expressed as least square means. The results demonstrated higher (P

The effect of osmolarity and glycerol different levels in soybean lecithin-based extender on the bull sperm quality after cryopreservation was examined using six Holstein bulls in a 2 × 3 factorial trial based on completely randomized design, with three levels of osmolarity (250, 300 and 350 mOsml) and two levels of glycerol (5 and 7 %) .In general, semen samples were collected 36 times (from each bull, six times). After the initial evaluation of semen, samples were mixed together and assigned to each of treatments. After freezing and thawing process, parameters that were evaluated including; motion characteristics by CASA, viability, plasma membrane integrity and morphology. The results showed that frozen-thawed sperm in treatment of G7P300 had higher values than the other groups for total motility (69.50 %), progressive motility (48.89 %), lateral head displacement (3.69 µm/s), curvilinear velocity (168.80 µm/s) and straightness coefficient (61.89 %) (P≤0.05). In the treatments containing seven and five percent of glycerol and osmotic pressure of 350 mOsml, plasma membrane integrity (23.14 and 25.63 %, respectively) and sperm viability (58.70 and 64.60 %, respectively) were lower compared to other treatments (P≤0.05). But, in terms of morphology, G7P350 (92.34 %) and G5P350 (92.57 %) treatments were better than other treatments. The results of these experiment showed that the extender contained of seven percentage of glycerol with osmalarity of 300 or 250 mOsml was more efficient for cryopreservation of Holstein bull sperm.

One of the reasons for reduction of fertility in sperm is extra production of free radicals during various stages including cryopreservation, storage and freeze-thawing process of sperm. Free radicals lead to changes in biochemical and ultrastructure of the sperm membrane, decreasing survival rate after thawing of sperm. Butylated hydroxytoluene (BHT) is a synthetic analogue of vitamin E that controls the auto-oxidation reaction by converting peroxy radicals to hydroperoxides.
OBGECTIVES: The purpose of this study was to investigate the effects of different levels of Butylated hydroxytoluen (BHT) to improve the quality of ram semen in the process of freezing/thawing.
In this study, five rams were used for semen collection twice a week. Different levels of BHT (1, 1.5, 2, 3 mM) were added to tris-yolk based diluents. After freezingthawing of semen samples, the dynamic parameters, viability, membrane integrity‚ sperm abnormality and lipid peroxidation (MDA) were evaluated.
the addition of 1.5, 2 mM BHT significantly improved total and progressive motility, viability and plasma membrane integrity and decreased the sperm abnormality percentage compared with the control group (P Statistical analysis of data showed that the addition of BHT to semen diluent improves the majority of sperm parameters after thawing.

The cryopreservation of spermatozoa has provided special opportunities for the preservation of genetic resources and improving breed programs by the artificial insemination technique (Holt, 1996). Sperm cryopreservation stimulates intracellular ice crystals formation, increasing osmotic and chilling injury that causes sperm cell damage (Isachenko et al. 2003). Freezing and thawing processes impose physical and chemical insults on the sperm membrane that decrease sperm viability and fertilizing ability (Alvarez and Storey, 1992). Both damages are associated with excessive generation of reactive oxygen species (ROS) and peroxidation of the phospholipids in the membrane (Wang et al. 1997; Lasso et al. 1994). High concentrations of ROS have a negative effect on sperm quality and increased degradation of DNA, lipid peroxidation and oxidative stress which inhibits sperm motility and changes the structure of sperm and finally the reduces the fertility (Aitken et al., 1997; Agarwal and Saleh, 2002; Khosrowbeygi and Zarghami, 2007; Zalata et al., 1995). Seminal plasma contains enzymes such as superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) which have an important role in the inhibition of the deleterious effects of ROS. Lipid peroxidation may be done due to lack of coordination between SOD, GPX, and CAT in seminal plasma or deficiency of total antioxidant capacity of the cell (Tavilani et al., 2008). Ascorbic acid is the main water-soluble antioxidant which acts as a scavenger for a whole range of reactive oxygen species. Ascorbic acid acts as a strong electron donor reacts with superoxide, peroxide and hydroxyl to form dehydroascorbic acid. Ascorbic acid protects sperm DNA against damage caused by H2O2 radical and reduces the amount of nitrite. This study was conducted to study the effects of adding ascorbic acid on sperm quality, plasma lipid peroxidation and antioxidant enzyme activities of ram semen after freeze- thawing process.
Material and Five sexually mature Ghezel rams (3 to 4 years of age) were used. Semen samples were collected every three days using an artificial vagina. In order to eliminate the individual differences, ejaculates containing sperm with >80% progressive motility, volume of 0.75 to 2 mL, sperm concentrations greater than 3 × 109 sperm/mL and sperm abnormalities of less than 10%, were pooled. Different levels of Ascorbic acid (0, 0.5, 1, 1.5 and 2 mg mL-1) were added in tris-egg yolk based diluent. After processing and freezing, the samples were stored in liquid nitrogen until the time of evaluation. After thawing of semen samples, Sperm motility characteristics were analyzed using computer-assisted sperm analysis. The sperm viability was determined by means of the nigrosin–eosin staining method. The hypo-osmotic swelling test (HOS-test) was used to evaluate functional sperm plasma membrane integrity after freeze-thawing. Sperm abnormalities were assessed using Hancock solution. Lipid peroxidation was measured with determining malondialdehyde and the seminal plasma antioxidant enzymes of glutathione peroxidase, superoxide dismutase and total antioxidant capacity using the RANDOX Laboratories kit. Statistical analyses were performed using SAS software (9.1.3) software using GLM procedures. The least square means were calculated to determine the differences between the experimental treatments for the post-thaw evaluation times.
The results showed that the 1 and 1.5 mg/mL ascorbic acid significantly improved the total motility (TM), progressive motility (PM), curvilinear velocity (VCL) compared to the control group (P