Effects of adding egg yolks of different avian species to Tris glycerol extender on the post-thawing quality of buck semen

Correlation between fatty acids levels in chicken, duck, goose, pigeon, quail and turkey egg yolks and post-thawed quality of ram semen

The comparison between adding egg yolks (EY) of chicken, duck, goose, pigeon, Japanese quail or turkey to the Tris glycerol extender on the quality of ram semen before freezing and post-thawing was evaluated. The correlation between fatty acids levels in egg yolks of different avian species and the post-thawed quality of ram semen was studied. The pooled ejaculates collected from five rams were extended with Tris EY glycerol extenders containing the EY of chicken, duck, goose, pigeon, quail or turkey and cryopreserved at -196°C. The straws were evaluated before freezing and post-thawing for sperm motility using a sperm cell analyser, vitality using a FluoVit kit and abnormality using a SpermBlue stain besides plasma-membrane and DNA integrities using a hypo-osmotic swelling test and a Halomax kit, respectively. The moisture, ash, protein and fatty acid (FA) contents of EY of chicken, duck, goose, pigeon, quail and turkey were analysed using a gas chromatograph. The chicken and quail EY extenders significantly improved the total progressive motility (32.05 ± 1.41 and 31.68 ± 1.43, respectively), vitality, plasma membrane and DNA integrities and abnormalities of post-thawing ram semen in comparison with other EY extenders. Pigeon EY had the lowest saturated fatty acids (SFAs) in comparison with the other types of EYs. The chicken and turkey EYs had the lowest percentage of (monounsaturated fatty acids) MUFAs in comparison with the other types of EYs. The highest percentage of polyunsaturated fatty acids (PUFAs) was observed in the turkey, pigeon and chicken EYs which were considered double or triple their percentage in duck and goose EYs, respectively. Significant positive correlations existed between SFAs levels and total motility, vitality, plasma membrane functionality and DNA integrity (0.77, 0.80, 0.67, 0.52, respectively). Significant negative correlations existed between gondoic EY levels and total motility, vitality, plasma membrane functionality and DNA integrity. In conclusion, the EYs of duck, goose, pigeon or turkey cannot substitute the chicken EY in ram semen extenders as they gave lower post-thawing quality. The quail EY can be used as a good replacer for chicken EY in the extender used for cryopreservation of ram semen. The EY composition of FAs can significantly affect the quality of ram semen post-thawing.

Effects of Heterologous Bovine Seminal Plasma-Supplemented Egg Yolk-Based Extender on Cryosurvivability of Pantja Buck Semen

The present study was conducted to observe the effects of removal of seminal plasma of Pantja buck semen and supplementation of bovine seminal plasma (BSP) in the extender before cryopreservation. In a preliminary experiment, different levels of BSP were supplemented (1, 3, 5, 7, and 9% v/v) in egg yolk (7.5% egg yolk)-tris (EYT) extender and used for cryopreservation of Pantja buck semen. Results in terms of motility, viability, plasma membrane integrity, acrosome integrity, and lipid peroxidation showed that 5% BSP was suitable for maintaining Pantja buck semen quality during cryopreservation. In the final experiment, pooled semen from four Pantja bucks was split into three aliquots (I, II, and III). Aliquot I was directly diluted in EYT extender and grouped as the control (C); aliquot II and III were washed separately with TALP solution and diluted as D1 (Washed semen with EYT extender) and D2 (Washed semen with EYT extender containing 5% BSP), respectively. Seminal attributes (sperm individual motility, viability, plasma membrane integrity, acrosome integrity, and total morphological abnormalities) were assessed at the postdilution, postequilibration, and post-thawing stages. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), malondialdehyde (MDA) concentration, and glutathione peroxidase (GSH-Px) activity were measured at post-thaw. Washed semen significantly improved (p < 0.05) seminal parameters at post-thaw compared with unwashed semen (control). A significant difference (p < 0.05) was observed in seminal attributes between freezing stages and between dilution groups. Significantly higher (p < 0.05) post-thaw sperm motility, viability, plasma membrane integrity, acrosome integrity, and GSH-Px activity, and significantly lower (p < 0.05) MDA concentration and extracellular release of enzymes (ALT, AST) were observed in group D2 compared with control and D1. The results of the present study demonstrated that cryopreservation of washed Pantja buck semen diluted with 5% BSP-supplemented EYT extender can improve post-thaw semen quality.

Implementation of a method for sperm cryopreservation in sceloporine lizards

Actual loss of lizard biodiversity continues, even with the implementation of conventional conservation programs. An approach including assisted reproductive techniques such as sperm cryopreservation may contribute to the management of endangered species. We developed a method for sperm cryopreservation in sceloporine lizards and compared the response among the studied species. Prior to the mating season, we obtained semen from adult males of Sceloporus aeneus (n = 21), Sceloporus grammicus (n = 20) and Sceloporus torquatus (n = 21) via pressure of the genital papilla. Volume and sperm concentration were measured before semen dilution in a Tris-egg yolk (TEY) medium to evaluate progressive motility, sperm viability, morphology, plasma membrane and acrosome integrity. Then, we cooled the remaining volumes to 5°C at a rate of 0.1°C per minute to incorporate glycerol (8% v/v) in two fractions. Immediately afterwards, we placed 40 μl of the mix on solid CO2 to form pellets and immersed them in liquid nitrogen for storage. We thawed the pellets at 29°C for 3 minutes and diluted them 1:1 (v/v) in TEY medium to assess sperm quality. We found a positive relationship between body weight and seminal volume in S. grammicus and S. torquatus and a negative correlation with sperm concentration in S. grammicus (P < 0.05). Moreover, we observed that the freezing-thawing process decreased sperm quality in the three species, mostly affecting motility and viability. However, S. torquatus and S. aeneus showed a higher sperm tolerance than S. grammicus.

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.

The replacement of fresh egg yolk by lyophilized egg yolk in Tris-base extender in cryopreserved Boer and Saanen semen

Egg yolk is a common cryoprotectant that can be used as a semen extender to protect the spermatozoa from damage during cryopreservation. Therefore, the aim of this study was to investigate the efficacy of fresh and lyophilized egg yolk, as a Tris-base extender, on the quality of cryopreserved goat semen. Semen from ten rams of two different breeds (Boer and Saanen) was collected using an artificial vagina. Each ejaculate sample was divided into four equal aliquots, which contained 20% of the fresh egg yolk (a control group), and then 10%, 15%, and 20% of the lyophilized egg yolk as a Tris-base extender. Sperm motility and kinematic parameters were determined using a computer assisted semen analyzer (CASA). The results showed that the addition of 20% of the fresh egg yolk in Tris-base extender exhibited significantly higher progressive motility, progressive fast motility, distance curve line (DCL), and beat cross frequency (BCF) parameters in the post-thaw Boer and Saanen goat sperm when compared with the addition of 10%, 15%, and 20% of the lyophilized egg yolk. The percentage of total motility, and immotile parameters in the post-thaw Boer and Saanen goat sperm were not significantly different between the control and 10%, 15% as well as 20% of the lyophilized egg yolk groups. Moreover, the percentage of viability parameter in the Boer and Saanen goat sperm was not significantly different between the control and 10% of the lyophilized egg yolk group, but showed significant difference between the control group and 15% and 20% of the lyophilized egg yolk groups. Furthermore, the interaction between the two breeds was significantly different in terms of head activity (HAC), and straightness (STR) parameter. In conclusion, the treatment with 20% of fresh egg yolk in Tris-base extender is superior to the lyophilized egg yolk. However, an addition of 10% of the lyophilized egg yolk in Tris-base extender presented the percentage of total motility and viability parameters showing no difference with 20% of fresh egg yolk. Therefore, 10% of the lyophilized egg yolk in Tris-base extender provided detail of the lyophilized egg yolk protocol in cryopreserved goat semen as an example of an alternative extender to 20% of fresh egg yolk for situations where an animal's origin represents a microbiological risk.

Effect of the donor´s age and type of extender (egg yolk versus clarified egg yolk) over the sperm quality of Majorera bucks preserved at 4 ºC: in vitro results and fertility trials

This study assessed the effect of donor´s age and two different extenders in the sperm quality of chilled semen in Majorera bucks. In experiment 1, semen was individually processed from 5 young (10–12 months old) and 4 mature (3–5 years old) bucks and then was diluted in two different extenders: EY (Tris‐glucose, 12% egg yolk) and CEY (Tris‐glucose, 12% clarified egg yolk) and cooled at 4°C; semen quality (sperm motility, percentages of alive spermatozoa, acrosome status and abnormal spermatozoa) was evaluated at 24, 48, 72 and 96 hr after cooling. In experiment II, 72 Majorera goats were assigned to four experimental groups: for groups 24‐EY (n = 18) and 24‐CEY (n = 18), goats were inseminated with EY and CEY cooled semen for 24 hr, respectively, while for groups 72‐EY (n = 18) and 72‐CEY (n = 18), goats were inseminated with EY and CEY cooled semen for 72 hr, respectively. In vitro results confirmed that only ejaculate volume and sperm concentration were significantly different between young and mature bucks. In addition, semen quality was similar between both diluents, presenting values for the first 48 hr similar to that recorded in fresh samples. The fertility rate was around 70% after 24 hr (4°C) in both groups, but the kidding rate was significantly lower (44.4%, p < .05) in goats inseminated with EY diluent preserved for 72 hr. Our results showed that the semen samples may be stored at 4°C in media with egg yolk or clarified egg yolk, and, therefore, the use of clarified egg yolk may represent a valid alternative to chill semen samples. Finally, young bucks (older than 10–12 months) of Majorera breed could be successfully used in breeding programmes with similar efficacy to older males.

Semen extenders: An evaluative overview of preservative mechanisms of semen and semen extenders

Reproduction is fundamental for all living things as it ensures the continued existence of a species and an improved economy in animal husbandry. Reproduction has developed since history, and diverse processes, such as artificial insemination and in vitro fertilization, have been developed. Semen extenders were discovered and developed to protect sperm from harmful factors, such as freeze and osmotic shock, oxidative stress, and cell injury by ice crystals. Semen extenders preserve sperm by stabilizing its properties, including sperm morphology, motility, and viability and membrane, acrosomal, and DNA integrity. Therefore, semen extenders must provide a favorable pH, adenosine triphosphate, anti-cooling and anti-freeze shock, and antioxidant activity to improve semen quality for fertilization. Hence, this review provides precise data on different semen extenders, preservative mechanisms, and essential additives for semen extenders in different animals.

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

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

Saadeldin I, Ba-Awadh H, G. Al-Mutary M, F. Moumen A, N. Alowaimer A, Abdalla H. Efficiency of Commercial Egg Yolk-Free and Egg Yolk-Supplemented Tris-Based Extenders for Dromedary Camel Semen Cryopreservation

Simple Summary

This study compared the efficiency of commercial egg yolk-free (AndroMed, OPTIXcell) and egg yolk-supplemented (Triladyl, Steridyl) Tris-based extenders for semen cryopreservation in dromedary camels. The camel-specific extender SHOTOR was used for reference. SHOTOR, Triladyl, Steridyl, AndroMed, and OPTIXcell can all be used for camel semen cryopreservation; however, SHOTOR and Triladyl provide the best post-thawing sperm quality.

Abstract

This study compared the efficiency of commercial egg yolk-free (AndroMed, OPTIXcell) and egg yolk-supplemented (Triladyl, Steridyl) Tris-based extenders for semen cryopreservation in seven adult dromedary camels. The camel-specific extender SHOTOR was used as control. The collected semen samples were evaluated and diluted with SHOTOR, Triladyl, Steridyl, AndroMed, or OPTIXcell. The diluted semen was gradually cooled and equilibrated for two hours before liquid nitrogen freezing. Semen was evaluated prior to freezing and after freeze-thawing cycles for motility, kinetics, vitality, abnormality, plasma membrane integrity, and DNA fragmentation using computer-assisted sperm analysis. In pre-freezing evaluation, progressive sperm motility was higher in SHOTOR-diluted samples (21.54 ± 1.83) than in samples diluted with Steridyl, OPTIXcell, or AndroMed (15.76 ± 1.80, 17.43 ± 1.10, and 13.27 ± 1.07, respectively). Moreover, Triladyl and SHOTOR resulted in significantly (p < 0.05) better sperm vitality and DNA integrity than all other diluents, but Triladyl resulted in a significantly (p < 0.05) better plasma membrane integrity (87.77 ± 0.31) than SHOTOR (85.48 ± 0.58). In the post-thawing evaluation, Triladyl led to significantly (p < 0.05) higher sperm motility (38.63 ± 0.81%; p < 0.05) when compared to SHOTOR, Steridyl or AndroMed (35.09 ± 1.341%, 34.4 ± 0.84%, and 31.99 ± 1.48%, respectively), with OPTIXcell being the least efficient (28.39 ± 0.86%). Progressive sperm motility was the highest when using Triladyl. Post-thawing curvilinear, straight line and average path sperm velocities were highest with Triladyl and lowest with AndroMed. Triladyl led to the highest linearity coefficient and straightness sperm coefficient, while SHOTOR to the highest DNA and plasma membrane integrity. OPTIXcell and AndroMed resulted in poor post-thawing sperm vitality, while Steridyl was less efficient than Triladyl. The highest rate of sperm abnormalities was recorded with OPTIXcell and the lowest with SHOTOR or Triladyl. In conclusion, SHOTOR, Triladyl, Steridyl, AndroMed, and OPTIXcell can all be used for camel semen cryopreservation; however, SHOTOR and Triladyl provided the best post-thawing sperm quality. Based on our findings, Triladyl is the best commercially available extender for dromedary camel semen cryopreservation to date.