Effect of dietary fish oil supplementation on ram semen freeze ability and fertility using soybean lecithin- and egg yolk-based extenders

Effect of olive, flaxseed, and grape seed nano-emulsion essential oils on semen buffalo freezability

The existing treatise targeted to compare the effects of adding different nano-emulsions essential oils (olive, flaxseed, and grapeseed oils) in freezing extender on semen quality and freezability in buffalo. Nano-emulsions were prepared from olive, flaxseed, and grapeseed oils and characterized for their sizes and shapes. Semen extended in four tubes were supplemented with 0 (control) and 3.5% nanoemulsion oils, including olive (NEO), flaxseed (NEFO) and grape seed oils (NEGSO) respectively. NEGSO resulted in the highest (p < 0.05) membrane integrity, vitality, progressive motility (P-motility) of sperm compared to the other groups in post-thawed buffalo bull semen (at 37 °C for 30 s). The addition of NEGSO had the best results for membrane integrity, progressive motility, and vitality of sperm after incubation (at 37 °C and 5% CO2 for 2 h). A superior (p < 0.05) value of total antioxidant capacity in frozen-thawed spermatozoa was monitored in all supplemented groups as relative to the control. The values of malondialdehyde (MDA) and nitric oxide (NO) were lower (p < 0.05) in NEGSO group compared with other groups. Both NEO and NEFO exhibited the same results for MDA, and NO levels (p > 0.05). All supplemented groups exhibited lower hydrogen peroxide levels (p < 0.05) as relative to the un-treated group. The lowest (p < 0.05) caspase 3 levels were verified in NEGSO treatment, followed by NEFO and NEO treatments. Post-thawed sperm showed ultrastructural damages in the control group, and theses damages were attenuated or resorted by the NEGSO, NEFO and NEO supplemented to freezing extender. In consequences with in vitro results regarding the sperm attribute, a greater pregnancy rate (92%) was observed in NEGSO group as compared with NEFO (88%), NEO (76%) and CON (68%) groups. Our findings demonstrate that NEGSO (3.5%) could be used as a new strategy in enhancing sperm functionality, potential fertility and reducing the oxidative damage and apoptosis markers. This could be significantly applicable for sperm physiology cryopreservation in the milieu of assisted reproduction systems.

Effect of dietary n-3 fatty acid and rooibos (Aspalathus linearis) supplementation on semen quality, sperm fatty acids and reproductive performance of aged male broiler breeders

The purpose of this study was to assess the effects of dietary fish oil (FO) and rooibos supplementation on semen quality, fatty acids composition and reproductive performance of aged male broiler breeders. Seventy-two 47-week-old Ross broiler breeder roosters were randomly assigned to a 2 × 3 factorial arrangements to include two FO concentrations (0% and 2%) and 3 rooibos concentrations (0%, 1.5% and 3%) for 13 weeks consecutive. The different diets affected semen parameters significantly (p < 0.05), except for the semen concentration and abnormality of the sperm. The sperm of the FO and 3% rooibos-treated group showed better motility and viability when compared to the other groups (p < 0.05). The susceptibility of semen to lipid peroxidation was increased in roosters fed the rooibos-free diets (p < 0.05), but it was reduced (p < 0.05) when the diet was supplemented with 1.5% and 3% rooibos. In addition, at 64 weeks, the highest concentration of testosterone was observed in the roosters fed a diet that included 2% FO and 3% rooibos (p < 0.05); however, the difference in testosterone levels between Week 52 and Week 64 was not significant (p > 0.05). The fertility rate of collected eggs from the FO and 3% rooibos group was higher (p < 0.05) than that of the other groups at the end of the experiment. In conclusion, dietary inclusion of FO along with rooibos improved seminal quality and reproduction performance in aged roosters.

Cryopreservation of Semen in Domestic Animals: A Review of Current Challenges, Applications, and Prospective Strategies

Cryopreservation is a way to preserve germplasm with applications in agriculture, biotechnology, and conservation of endangered animals. Cryopreservation has been available for over a century, yet, using current methods, only around 50% of spermatozoa retain their viability after cryopreservation. This loss is associated with damage to different sperm components including the plasma membrane, nucleus, mitochondria, proteins, mRNAs, and microRNAs. To mitigate this damage, conventional strategies use chemical additives that include classical cryoprotectants such as glycerol, as well as antioxidants, fatty acids, sugars, amino acids, and membrane stabilizers. However, clearly current protocols do not prevent all damage. This may be due to the imperfect function of antioxidants and the probable conversion of media components to more toxic forms during cryopreservation.

Influence of alpha linolenic acid on the motility, viability, antioxidant activity and fertility of frozen-thawed New Zealand white rabbit buck semen

Freezing and thawing processes result in production and accumulation of high concentrations of reactive oxygen species that are detrimental to spermatozoal motility and fertility. Therefore, supplementation of exogenous source of antioxidants to freezing diluent is crucial. The aim of the present study was to investigate for the first time whether supplementation of semen diluent with alpha linolenic acid (ALA) can improve motility, viability, membrane integrity, antioxidant status and fertility of post-thaw rabbit spermatozoa. Semen was collected and pooled from fifteen New Zealand white rabbit bucks. Semen samples were diluted with a tris-citrate-glucose (TCG) extender supplemented with ALA (0, 50, 75 and 100 μmol). Then, extended rabbit semen was cooled at 5°C and cryopreserved in liquid nitrogen. After thawing, spermatozoal quality parameters (individual motility %, viability %, osmotic resistance %, and acrosome integrity %), antioxidant activity (SOD, CAT, and GSH activities), lipid peroxidation (malondialdehyde) and fertility (conception and kindling rates) were evaluated. Results revealed that supplementation of rabbit semen extender with 50 μmol ALA significantly (P<0.05) increased spermatozoal characteristics including motility (56.54%), viability (60.01%), acrosome status (72.66%) and membrane integrity (59.13%). The activity of semen antioxidant enzymes (SOD, CAT, and GSH) showed a significant improvement with a marked decrease in lipid peroxidation. Moreover, the conception (73.30%) and kindling (70.00%) rates were significantly (P<0.05) higher in does inseminated with thawed semen treated with 50 μmol ALA in comparison with other concentrations (0, 75 and 100 μmol). In summary, supplementation of rabbit semen extender with 50 μmol ALA improved motility, viability, membrane integrity, acrosome integrity, antioxidant enzymes activity and fertility of post-thaw rabbit spermatozoa. Our findings suggested that higher concentrations of ALA are detrimental to post-thaw characteristics of New Zealand white rabbit buck spermatozoa. To achieve better results, the semen freezing extender should be supplemented with ALA at lower concentrations, especially 50 μmol.

Sperm flow cytometric parameters, antioxidant status, and testicular histomorphology in roosters fed diets supplemented with camphor

Genetic selection based on the high growth rate and consequently high slaughter weight in broiler chickens has caused many problems in broiler breeders. A negative correlation between growth and reproductive traits has declined semen quality and fertility in roosters. The present study aimed to evaluate the effects of camphor levels on some reproductive parameters included semen parameters, antioxidant status, and testicular development in broiler breeder roosters. Thirty-five ROSS 308 broiler breeder roosters were divided into 5 groups to receive camphor (C) levels: C0, C50, C250, C750, and C1000 ppm for 12 consecutive weeks (31–43 wk). Body weight, seminal volume, sperm concentration, and percentage of live and morphologically normal sperm were not affected by diets (P > 0.05), however, significantly were changed by bird age over the experiment (P < 0.05). Semen quality factor (SQF) significantly was affected by both diets and age (P < 0.05). Mitochondrial activity, apoptotic-like changes, and DNA fragmentation were improved in the groups fed camphor levels compared to the control group (P < 0.05). Testes weight (left, right, and combined weights) and gonadosomatic index were increased linearly by the camphor supplementation (P < 0.05). The serum activity of glutathione peroxidase (GP_X) was not affected by treatments, however, superoxide dismutase (SOD) activity, ferric ion reducing antioxidant power (FRAP), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity were significantly higher in C50, C250, and C750, respectively (P < 0.05). The lower malondialdehyde (MDA) content in the testes and liver samples was observed in C750 (P < 0.05). Excluding the number of Sertoli cells and blood vessels, other histomorphological traits of testes showed one of the linear or quadratic responses to the camphor levels (P < 0.05). It can be concluded that camphor as an antioxidant source may improve reproduction performance in roosters.

The Cryopreserved Sperm Traits of Various Ram Breeds: Towards Biodiversity Conservation

The aim of our research was to compare three Slovak sheep breeds in the quality parameters of cryopreserved sperm. The ejaculates of Slovak Dairy (SD), Native Wallachian (NW), and Improved Wallachian (IW) sheep rams (n = 12) were collected by electro-ejaculation. Heterospermic samples were created from suitable ejaculates, separately for each breed (at least 90% of total and 80% of progressive motility). Samples were equilibrated in a Triladyl® diluent and frozen by automated freezing. Sperm samples were subjected to the motility, morphology, (CASA), viability and apoptosis (DRAQ7/Yo-Pro-1), fertilizing capability (penetration/fertilization test (P/F) in vitro) and acrosomal status (transmission electron microscopy) assays before freezing and after thawing. It was found that there were no significant differences (p < 0.05) between the evaluated breeds in motility, viability, apoptosis, morphological properties, and fertilizing ability of cryopreserved sperm. Significant differences occurred in acrosomal status. Our results demonstrate that the use of the selected cryopreservation protocol is suitable for at least three different sheep breeds, which can greatly benefit the biodiversity protection and simplifies the creation of an animal genetic resources gene bank.

Cryopreservation of ram semen: Manual versus programmable freezing and different lengths of equilibration

The aim of our study was to examine effects of the length of semen equilibration as well as two freezing techniques on ram sperm post-thaw quality. The ejaculates of Wallachian sheep rams (n = 12) were collected by an electro-ejaculation, equilibrated in a Triladyl® (0, 2, 4, 6, and 8 h) containing glycerol and egg yolk and frozen by programmable freezing (PF) or manual freezing (MF). After thawing, sperm samples were subjected to the motility (computer-assisted sperm analysis [CASA]), viability (SYBR-14/PI), and fertilizing ability (FA) (in vitro penetration/fertilization test on bovine oocytes) assays. It was found that the equilibration of 6 h (E-6) ensured higher post-thaw sperm motility and progressive movement compared with other lengths tested, irrespective of a freezing technique. The E-6 sperm viability did not differ between PF and MF but was lower (P < 0.05) than control. Sperm FA (E-6) was similar in PF (60.44%) and MF (62%) but slightly lower than in fresh (72.8%). Our data demonstrate that the use of MF was comparable with PF, which can be applied in the field conditions without need in a piece of cost-expensive equipment, which can greatly benefit the gene bank of animal genetic resources.

Flaxseed Oil as a Source of Omega n-3 Fatty Acids to Improve Semen Quality from Livestock Animals: A Review

Simple Summary

In response to the conservation of threatened livestock species, different strategies to improve semen quality have been developed. However, spermatozoa remain sensitive to cryopreservation damages especially that of avian species, thus limiting the use of reproductive biotechnologies such as artificial insemination in the conservation programs. Improving semen quality through dietary inclusion of long-chain polyunsaturated fatty acids sources mainly omega n-3 has received research interest. This review explains the role of flaxseed oil as a source of omega n-3 fatty acids to improve semen quality. Comprehensive information elaborated in this review is believed to promote the use of flaxseed oil as an alternative source of omega n-3 fatty acids to fish oil. This is because fisheries are over-exploited and could collapse.

Abstract

The demand to conserve indigenous species through the cryo-gene bank is increasing. Spermatozoa remain sensitive to cryopreservation damages especially that of avian species thus limiting the use of reproductive biotechnologies such as artificial insemination in the conservation programs. Long-chain polyunsaturated fatty acid (LCPUFAs), specifically omega n-3, expanded a research interest to improve animal reproductive efficiency through improving spermatozoa quality. This is driven by the fact that mammals cannot synthesize omega-3 de-novo because they lack delta-12 and delta-15 desaturase enzymes thus supplemented in the diet is mandatory. Delta-12 and delta-15 add a double bond at the 12th and 15th carbon-carbon bond from the methyl end of fatty acids, lengthening the chain to 22 carbon molecules. Fish oil is a pioneer source of omega n-3 and n-6 fatty acids. However, there is a report that numerous fisheries are over-exploited and could collapse. Furthermore, processing techniques used for processing by-products could complement alterations of the amino acid profile and reduce protein retrieval. Alternatively, flaxseed oil contains ±52–58% of total fatty acids and lignans in the form of α-linolenic and linoleic acid. Alpha-linolenic acid (ALA,18:3n-3) is enzymatically broken-down de-novo by delta-6 desaturase and lengthened into a long-chain carbon molecule such as eicosapentaenoic acid (C20:5n-3). Nevertheless, controversial findings following the enrichment of diet with flaxseed oil have been reported. Therefore, this paper is aimed to postulate the role of flaxseed oil as an alternative source of omega n-3 and n-6 fatty acids to improve semen quality and quantity from livestock animals. These include the interaction between docosahexaenoic acid (DHA) and spermatogenesis, the interaction between docosahexaenoic acid (DHA) and testicular cells, and the effect of flaxseed oil on semen quality. It additionally assesses the antioxidants to balance the level of PUFAs in the semen.

Epigallocatechin 3-gallate improves the quality of bull semen cryopreservation

To determine the effects of epigallocatechin-3-gallate (EGCG) on the cryopreservation of bovine semen, epigallocatechin-3-gallate dissolved with double distilled water to 0.2, 0.4, 0.6 and 0.8 mg/ml were added to the cryopreservation diluent of the bull semen. Then, we used computer-assisted analysis of semen kinematic parameters, staining method to detect membrane function, acrosome integrity, enzyme-linked immunosorbent assay to detect catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malondialdehydes (MDA) and reactive oxygen levels. The results showed that adding 0.6 mg/L of epigallocatechin-3-gallate could improve the cryopreserved sperm quality, which significantly increased the total motility, distance average path, distance straight line, distance curved line, average path velocity, curvilinear-velocity, straight-line velocity, amplitude of lateral head displacement and beat/cross frequency, as well as sperm CAT, GSH-Px and SOD levels (p < 0.05), whilst reducing the reactive oxygen species and MDA levels (p < 0.05). Hence, these results indicate that the addition of 0.6 mg/ml of EGCG has a protective effect on the cryopreservation of the bovine semen.

Effects of different ultrastructures of lecithin on cryosurvival of goat spermatozoa

This study was to evaluate the effects of two different ultrastructures of lecithin including nanoparticles (NPE mostly nanomicelles) and lecithin nanoliposome (NLE) with egg yolk extender (EYE) on goat sperm cryopreservation. Semen samples were collected from 6 goats, then pooled, diluted and then frozen. Motility and motion parameters, plasma membrane integrity and functionality, morphology, apoptosis status (Annexin V-PI), acrosome integrity, DNA fragmentation and in vitro fertilisation were assessed. Total motility and most motion parameters were higher in EYE (p < .05) compared with the two lecithin extenders, while there were no significant differences between NLE and NPE. NLE and NPE had higher values for viable spermatozoa (Annexin V-PI) (p < .05) compared with EYE. The highest value for dead spermatozoa was observed in EYE (p = .08). A higher percentage of DNA fragmentation (p < .05) was detected in EYE compared with NPE. Plasma membrane integrity and functionality, morphology, acrosome integrity and fertility of spermatozoa indicated no significant differences between extenders. Data suggested that ultrastructural changes of lecithin (micelles versus. liposome) could not improve the sperm cryosurvival of goat spermatozoa. Moreover, we cannot also claim that lecithin-based diluent supplies better protection compared with the egg yolk in goat.

Effects of Apigenin and Astragalus Polysaccharide on the Cryopreservation of Bull Semen

The purpose of this study was to determine the effects of apigenin and astragalus polysaccharides on the cryopreservation of bovine semen. Apigenin, astragalus polysaccharides, or their combination were added to a frozen diluent of bovine semen. Afterwards, Computer Assisted Semen Analysis (CASA), membrane functionality, acrosome integrity, mitochondrial integrity, CAT, SOD, GSH-Px, MDA, and ROS detection were conducted. The results showed that adding 0.2 mmol/L AP or 0.5 mg/mL APS could improve the quality of frozen sperm. Compared to 0.2 mmol/L AP alone, the combination of 0.2 mmol/L AP and 0.3 mg/mL APS significantly increased the total motility (TM), average path distance (DAP), straight line distance (DSL), average path velocity (VAP), curvilinear velocity (VCL), wobble (WOB), and sperm CAT and SOD levels (p < 0.05), while reducing the ROS and MDA levels (p < 0.05). These results indicated that the addition of 0.2 mmol/L AP or 0.5 mg/mL APS alone has a protective effect on the freezing of bovine semen. Compared to the addition of 0.2 mmol/L AP, a combination of 0.2 mmol/L AP and 0.3 mg/mL APS could further improve the quality of frozen semen.

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.

Uso da galactose na vitrificação de sêmen ovino em palhetas

Resumo A vitrificação de espermatozoides é uma técnica que apresenta grande potencial para criopreservação de material genético, e sua eficácia tem sido superior aos métodos convencionais em algumas espécies. No entanto, existem poucos estudos sobre sua eficiência com sêmen ejaculado de carneiros e o uso da galactose como crioprotetor extracelular durante a vitrificação. Objetivou-se com este estudo avaliar o efeito da galactose (0,01 M), associada ou não ao glicerol (3% e 7%), em meio comercial (Steridyl® - controle), na criopreservação de espermatozoides de carneiros pelo método de palhetas, comparando o método clássico de congelação e a vitrificação. Ejaculados de seis carneiros da raça Dorper em idade reprodutiva foram coletados com vagina artificial, aliquotados, diluídos individualmente (100 × 106 espermatozoides/mL) nos meios testados, envasados em palhetas de 0,25 mL e submetidos à congelação clássica ou vitrificação. Foram analisadas a cinemática, morfologia, morfometria, viabilidade, integridade física e funcional da membrana espermática. A congelação clássica obteve melhores resultados de motilidade total e progressiva do que a vitrificação nos quatro extensores testados, uma vez que as amostras vitrificadas não apresentaram motilidade pós-reaquecimento (p < 0,05). A adição de galactose ou glicerol ao meio comercial não trouxe efeito benéfico tanto para a vitrificação quanto congelação clássica.

Effects of k-carrageenan supplementation or in combination with cholesterol-loaded cyclodextrin following freezing-thawing process of rooster spermatozoa

This experimental research purposely seeks to explore the effect of supplementing k-carrageenan (k-CRG) or CLC (cholesterol-loaded cyclodextrins) or the combined effect of k-CRG and CLC as supplements of antioxidants to an extender for rooster semen freezing. A total of 75 neat pooled ejaculates were collected twice a week from twenty-five (25) commercial line arbor acres broiler roosters (30 wks) during the experimental period. In each replicate, semen samples (n= 15, three ejaculates per rooster) were pooled and divided into nine equal aliquots, and each aliquot was diluted with one of the following extender supplemented with k-CRG, CLC, and k-CRG + CLC after which it was subjected to cryopreservation process using the "pellet" method. In study I, the supplementation of extenders with k-CRG was in five equal aliquots as follows; (0.2, 0.4, 0.6, 0.8) mg/mL and control group (k-CRG 0) mg/mL while in Study II, there was a combination of both k-CRG + CLC (0.4 mg/mL + 1.5 mg/mL, respectively), 0.4 mg/mL k-CRG, 1.5 mg/mL CLC and control group. Sperm quality parameters, endogenous antioxidant enzymes, lipid peroxidation (MDA) and ROS were all assessed after the freeze-thaw process. Our findings in study I indicated that at post-thaw, an optimum 0.4 mg/mL k-CRG supplementation in the extender improved semen quality parameters, endogenous enzymes, MDA and ROS in comparison to the control group. Interestingly prior to the freeze-thaw process, it was depicted in study II that combined k-CRG + CLC (0.4 mg/mL+1.5 mg/mL) inclusion in the extender provided maximum protection to sperm quality parameters, endogenous enzymes, MDA and ROS in comparison to 1.5 mg/mL CLC and control group at post-thaw. Besides, there was also a significant difference observed in the extenders supplemented with combined k-CRG + CLC (0.4 mg/mL +1.5 mg/mL) when compared to 0.4 mg/mL k-CRG for semen quality parameters and endogenous antioxidant enzymes (SOD, CAT, and GPx) but no significant difference was observed for MDA and ROS. Also, there was a significant difference observed in the extender supplemented with 1.5 mg/mL CLC when compared to the control group for semen quality parameters, SOD, CAT, and MDA but no significant difference for GPx and ROS at post-thaw. In conclusion, k-CRG at an optimal dosage of 0.4 mg/mL proved effective for improving post-thaw sperm quality but its combined addition k-CRG + CLC at an optimal concentration of (0.4 + 1.5) mg/mL in the extender provided greater protection to the rooster spermatozoa at post-thaw.

Changes in seminal parameters and hormonal profile with use of aromatase inhibitor in management of aging broiler breeder roosters

An excessive amount of aromatase enzyme reduces reproductive performance in aging roosters. Testosterone metabolism by aromatase enzyme is one of the reasons for reduced testosterone and lower fertility of aging roosters. The purpose of this study was to determine the effects of Exemestane (EX), as a steroidal aromatase inhibitor, on the seminal parameters and reproductive hormones of aging roosters. A total of 20 roosters (45 wk of age) were housed in individual cages and received a standard basal diet and oral EX capsules for 60 D at the daily doses per rooster (mg/rooster) in the following experimental groups: 0 mg (CTRL), 0.25 mg (Ex-0.25), 0.5 mg (Ex-0.5), and 1.5 mg (Ex-1.5). Sperm samples were obtained on days 1, 20, 40, and 60 of experiment. Blood samples were taken on days 1 and 60. The results indicated that different EX dosages affected semen parameters (P < 0.05) other than semen volume, morphology, apoptosis, and acrosome integrity. Various semen characteristics were significant (P < 0.05) during different times of the experiment, with the exception of semen volume, total motility, membrane integrity, morphology, apoptosis, and acrosome integrity. Roosters that received 0.5 mg of EX had higher percentages of sperm concentration, total motility, progressive motility, membrane integrity, viability, and mitochondrial activity (P < 0.05). There were lower concentrations of malondialdehyde in the CTRL (0 mg) and Ex-0.25 groups (P < 0.05). Although there was no significant difference in hormones at day 0 of the experiment (P > 0.05), roosters in the Ex-0.5 had higher concentration of testosterone as well as lower of aromatase activity at day 60 (P < 0.05). It can be concluded that EX improved semen parameters and testosterone, which ultimately can increase fertility in the aging broiler breeder roosters.

Pre-conditioning with Xanthine oxidase to improve post thawed quality of bull sperm

The purpose of this study was to examine the effects of sub-lethal concentration of Xanthine oxidase (XO) on the post-thawed bull sperm quality. Semen samples were collected from four Holstein bulls, twice a week and during three consecutive weeks (n = 24 total ejaculates). After collection in each replicate, semen samples were pooled and then frozen by semen extender containing different concentrations [0 (XO-0), 0.05 (XO-0.05), 0.5 (XO-0.5), 5 (XO-5), 50 (XO-50) and 500 (XO-500) μM] of XO. After thawing, motion parameters (SCA), plasma membrane functionality (HOST), apoptosis status (Phosphatidylserine translocation assay), mitochondrial activity (Rhodamine 123), and acrosome integrity (PSA), were evaluated. The results showed that total motility, VAP, VSL, VCL, STR, and LIN were lower in XO-50 and XO-500 compared to other groups (P < 0.05). Progressive motility were higher in XO-0.05 and XO-0.5 compared to XO-0, XO-50, and XO-500 (P < 0.05). Mitochondrial activity was highest in XO-0.05 and XO-0.5 groups. Sperm plasma membrane functionality was significantly greater in XO-0, XO-0.05, XO-0.5, and XO-5 than that of XO-50 and XO-500. Xanthine oxidase had not significant effects on acrosome integrity and dead spermatozoa. Higher percentage of live spermatozoa was recorded for XO-0, XO-0.05, XO-0.5, and XO-5; however, the lower amount of apoptotic spermatozoa was detected in the aforementioned groups (P < 0.05). In conclusion, it seems that XO at lower doses may have beneficial effects on post-thawed bull sperm quality.

Single layer colloid centrifugation technique improves motility, viability and chromatin integrity of ram spermatozoa after thawing

The cell membrane of ram spermatozoa is more sensitive to the freezing process than in other species due to its composition. As a result, the quality and viability of frozen thawed ram spermatozoa are often poor, which together with the specific structure of the ewe's cervix are the main reasons for lower fertility in ewes after intracervical insemination. In the present study we investigated the effects of semen centrifugation through a single layer of a species-specific colloid (Androcoll-O) on post-thaw quality of ram spermatozoa. Motility, viability and morphology were analysed 0, 6, 12 and 24 h after thawing. DNA fragmentation index (%DFI) of the samples was assessed 0 h after thawing, by SCSA™. Membrane and acrosome integrity of spermatozoa were analysed by Sybr-14/PI/PNA test 0 h after thawing. The proportion of motile spermatozoa was significantly higher in SLC - selected samples in comparison to control (not SLC - selected) samples at 0, 6, 12 (P < 0.001) and 24 h (P < 0.05). The proportion of viable spermatozoa was also significantly higher in SLC - selected samples in comparison to control samples at all times (P < 0.001). The proportion of abnormal acrosomes and morphologically abnormal spermatozoa (MAS) were significantly lower in SLC - selected samples compared to control samples at all times (P < 0.001). Analysis of chromatin stability revealed significantly lower %DFI values in SLC - selected samples compared to control samples (P < 0.001). The SYBR-14/PI/PNA test also revealed significantly better values in SLC - selected compared to control samples (P < 0.05). In conclusion, single layer colloid centrifugation significantly improved post-thaw quality and longevity of ram spermatozoa, making it suitable for artificial insemination initiatives.

Comparison Between an Animal-Derived Product Medium and a Chemically Defined Medium for Ram Sperm Cryopreservation

Animal-derived products are widely used in sperm cryopreservation for their cryoprotective properties. These components, however, tend to be replaced because of sanitary risks. STEMALPHA.CRYO3 (Ref. 5617; Stem Alpha, Saint-Genis-l'Argentière, France), called "CRYO3," is a chemically defined preservation medium currently used for freezing human tissue and adult stem cells. The aim of this study was to evaluate the effect of a CRYO3-based medium on ram sperm freezing regarding in vitro parameters and in vivo fertility. Semen from nine Charolais rams was collected using an artificial vagina, then split and frozen using two media: a CRYO3-based medium or a control medium containing egg yolk (10%) and milk (45%). Sperm membrane integrity (propidium iodide [PI]/SYBR-14 and calcein AM/ethidium homodimer-1), acrosome integrity (FITC-PNA/PI), and mitochondrial membrane potential (JC-1) were assessed using flow cytometry, while functional membrane integrity was assessed using a hypo-osmotic swelling test and motility parameters, evaluated by computer-assisted sperm analysis. Pregnancy rates, prolificacy, and the average daily weight gain (DWG) of lambs were evaluated after performing 195 laparoscopic inseminations. The control medium showed significantly higher results than CRYO-based medium for all in vitro parameters, except for linearity and straightness (motions parameters). Conversely, field trials showed no significant difference between the control medium and the CRYO3-based medium for pregnancy rates (72.2% and 67.9%, respectively), prolificacy (1.8 and 1.6, respectively), and the DWG (0.34 and 0.35 kg/d, respectively). This preliminary study showed that CRYO3 cannot replace egg yolk and milk in freezing extenders for commercial purposes. However, as laparoscopic inseminations allowed a 67% pregnancy rate, CRYO3-based medium remains an option for international transport or long-term storage of genetic diversity.

Sperm quality characteristics and fertilization capacity after cryopreservation of rooster semen in extender exposed to a magnetic field

There has not been as much success in the effectiveness of avian semen cryopreservation as that of mammalian semen cryopreservation. This has been attributed to the unique characteristics of poultry sperm. In the area of mammalian semen, the use of magnetized extenders has enhanced the cryo-resistance of sperm in some species. The applicability of this strategy to avian semen has not yet been evaluated. The purpose of this study was to evaluate the effects on sperm quality and fertility after magnetization of extenders and use of these extenders for cryopreservation of rooster semen. Extenders were passed between two neodymium magnets that produced different magnetic induction values (0, 2000, 4000 and 6000 G). Physicochemical properties of the extenders were assessed and then semen samples were cryopreserved in the magnetized extenders. The smallest cluster sizes and zeta potentials in the extenders were observed in the extender magnetized at 2000 gauss (G). There were greater percentages of sperm total motility, viability and mitochondrial membrane potential in semen treated with the extender magnetized at 2000 G A greater percentage of sperm with enhanced membrane functionality was observed when sperm were stored in extenders magnetized with 2000 G and 4000 G. In a field trial, there were greater percentages of fertility and hatching rates of eggs using semen treated with extenders magnetized at 2000 G and 4000 G. Cryopreservation of rooster semen with magnetized extenders at 2000-4000 G resulted in enhanced quality indices of thawed sperm as well as the fertility capacity of the cryopreserved semen.

Enhancement of sperm motility and viability by turmeric by-product dietary supplementation in roosters

Improving sperm motility and viability are major goals to improve efficiency in the poultry industry. In this study, the effects of supplemental dietary turmeric by-product (TBP) from commercial turmeric production on sperm motility, viability, and antioxidative status were examined in domestic fowl. Mature Rhode Island Red roosters were divided into two groups - controls (groupC) without TBP administration and test subjects (groupT) fed a basal diet supplemented with 0.8g of TBP/day in a temperature-controlled rearing facility (Experiment 1) and 1.6g/day under heat stress (Experiment 2) for 4 weeks. In Experiment 1, TBP dietary supplementation increased the sperm motility variables straight-line velocity, curvilinear velocity, and linearity based on a computer-assisted semen analysis, 2 weeks following TBP supplementation. In Experiment 2, using flow cytometry, sperm viability at 3 and 4 weeks following TBP supplementation was greater in Group T than C, and this increase was consistent with a reduction in reactive oxygen species (ROS) production at 2 and 4 weeks. The results of both experiments clearly demonstrate that dietary supplementation with TBP enhanced sperm motility in the controlled-temperature conditions as well as sperm viability, and reduced ROS generation when heat stress prevailed. Considering its potential application in a range of environments, TBP may serve as an economical and potent antioxidant to improve rooster fertility.

Fertility and flow cytometry study of frozen-thawed sperm in cryopreservation medium supplemented with soybean lecithin

Semen cryopreservation can provide genetic resources for a large number of females from a small number of superior males. Optimization of cryopreservation media to achieve the highest quality of post-thaw semen is crucial. Soybean lecithin has evaluated as a plant-based cryoprotectant for substitution of egg yolk in ram semen extender. Flow cytometric and fertility assessments were applied following cryopreservation procedure in two experimental groups (SL group: extender containing 1% w/v soybean lecithin and EY group: extender containing 20% v/v egg yolk). The higher percentage of live sperm and the lower percentage of dead sperm were obtained in SL (47.66 ± 1.38, 52.33 ± 1.69, respectively) extender compared to EY (41.16 ± 1.38, 58.83 ± 1.69). For motion characteristics, plasma membrane integrity, acrosome integrity and mitochondria activity, no significant difference was observed between SL and EY extenders. In artificial insemination experiment, there was no significant difference in pregnancy rate, lambing rate and twining rate between SL and EY extenders. It can be concluded that SL extender can be an efficient alternative extender to preserve ram sperm during cryopreservation procedure without adverse effects.