Effect of Addition of Taurine on the Liquid Storage (5°C) of Mithun (Bos frontalis) Semen

Supplementation with MitoTEMPO before cryopreservation improves sperm quality and fertility potential of Piedmontese beef bull semen

The purpose of this study was to improve the quality of frozen-thawed Piedmontese bull semen by incorporating MitoTEMPO (MT) in extended semen before cryopreservation. Semen was collected from 4 fertile bulls, using an artificial vagina, once weekly for 6 consecutive weeks. Semen samples were pooled, diluted with Bullxcell® extender, and supplemented with different concentrations of MT (0 as control, 5, 10, 20, 40, and 80 μM) before cooling, equilibration, and freezing procedures. The frozen-thawed semen was assessed for motility, vitality, acrosome intactness, plasma membrane integrity, DNA integrity, apoptosis, mitochondrial membrane potential, intracellular ROS level and in vitro fertilizing capability. The results showed that MT at concentrations of 10, 20, and 40 μM improved the total, progressive, and rapid motility directly after thawing while, at the highest tested concentration (80 μM), it decreased the progressive and rapid motility after 1, 2, and 3 h of incubation. The sperm kinetics including STR and LIN were noticeably increased at concentrations of 10, 20, and 40 μM directly after thawing (0 h), whereas the MT effect was variable on the other sperm kinetics during the different incubation periods. MitoTEMPO improved the sperm vitality at all tested concentrations, while the acrosomal and DNA integrity were improved at 20 μM and the mitochondrial membrane potentials was increased at 80 μM. The cleavage and blastocyst formation rates were significantly increased by using semen treated with 20 μM MT compared with controls. These findings suggest a potential use of MT mainly at a concentration of 20 μM as an additive in the cryopreservation media of bull semen to improve sperm quality.

Taurine induces hormesis in multiple biological models: May have transformative implications for overall societal health

This paper represents the first integrative assessment and documentation of taurine-induced hormetic effects in the biological and biomedical areas, their dose response features, mechanistic frameworks, and possible public health, therapeutic and commercial applications. Taurine-induced hormetic effects are documented in a wide range of experimental models, cell types and for numerous biological endpoints, with most of these experimental findings being reported within the past five years. It is suggested that the concept of hormesis may have a transformative effect on taurine research and its public health and therapeutic applications.

L-Proline: A Promising Tool for Boosting Cryotolerance and Fertilizing Ability of Cryopreserved Sperm in Animals

Sperm cryopreservation technology significantly contributes to the safeguarding of genetic resources, particularly for endangered species, and supports the use of artificial insemination in domestic animals. Therefore, cryopreservation can negatively affect sperm health and function leading to reduce the freezing ability and fertility potential. Therefore, it is essential to prioritize the improvement of cryotolerance in cryopreserved sperm to enhance reproductive efficiency and ensure sustainability in livestock herds. The main reason for sperm dysfunction after thawing may be related to the excessive amount of oxidative stress (OS) produced during cryopreservation. Scientists have different ways for counteracting this OS including the use of plant extracts, enzymes, minerals, anti-freezing proteins, and amino acids. Recently, one such amino acid is L-proline (LP), which has multiple roles such as osmotic and OS defense, nitrogen, and carbon metabolism, as well as cell survival and signaling. LP has been found in seminal plasma and has recently been added to the freezing extender to improve the various post-thaw parameters of sperm. This improvement is related to the ability of LP to reduce the OS, sustain the plasma membrane and to act as an osmoregulatory agent. Moreover, LP can suppress cell apoptosis by modulating intracellular redox in sperm. This review addresses the ongoing research on the addition of L-proline as an osmoregulatory agent in freezing extenders to increase the cryotolerance of animal spermatozoa to freeze-thaw.

Effect of melatonin on cryopreservation of Beijing you chicken (gallus gallus) spermatozoa

Beijing You Chicken, a valuable local chicken breed from Beijing, China, was once listed as an endangered breed. From the point of view of conservation, the preservation of this breed is an important task for the local researchers. Semen cryopreservation is a popular method to maintain valuable species. However, during cryopreservation, semen is susceptible to oxidative damage. Melatonin is a potent antioxidant and free radical scavenger, so it has been selected to improve the efficiency of sperm cryopreservation. In this study, the chicken semen was treated with different concentrations of melatonin in the cryopreservation solution. The results showed that melatonin at concentrations of 10-3 M and 10-5 M significantly improved sperm progressive motility and total motility, respectively, compared to the control (P < 0.05). Melatonin at 10-3 M also significantly improved the plasma membrane and acrosome integrity of spermatozoa compared to the control. The mechanisms are that melatonin significantly reduces the level of ROS and preserves sperm mitochondrial membrane potential. Most importantly, the melatonin-treated cryopreserved chicken sperm after artificial insemination significantly increased the hatching rate of chicks compared to the control (p < 0.05). The results show that melatonin has a positive effect on the quality of the cryopreserved spermatozoa. These results provide the theoretical and practical basis for using melatonin to improve Beijing You Chicken conservation, and they may also be applicable to poultry as a whole.

Mito-Tempo improves acrosome integrity of frozen-thawed epididymal spermatozoa in tomcats

Introduction

In tomcats, epididymal spermatozoa provide an additional source of male gametes available for cryopreservation. While this procedure is feasible, the survival rate and motility of epididymal cat spermatozoa are both low after thawing. Cryopreservation is known to induce oxidative stress in spermatozoa, with mitochondria and the plasma membrane being the two major generation sites, and an imbalanced presence of free radicals is a possible cause for this low survival rate. Different antioxidants have been tested before for their effect on cryopreserved cat spermatozoa quality, with varying results. Here, we used Mito-Tempo, which is a synthetic mitochondria-targeted antioxidant and a specific scavenger of the mitochondrial superoxide system. By supplementing Mito-Tempo with the freezing extender, we aimed to improve the sperm quality of frozen-thawed cat epididymal spermatozoa.

Methods

Epididymal spermatozoa obtained from twelve tomcats were assessed for motility and concentration. Prior to freezing, samples were diluted in TRIS buffered extender with egg yolk and glycerol and divided into five aliquots supplemented with 0 (control), 0.5, 5, 50, and 1005M of Mito-Tempo. After thawing, sperm motility, concentration, morphology, plasma membrane integrity, acrosome integrity, and mitochondrial membrane potential were evaluated. A Friedman rank sum test with a Bonferroni post-hoc test was used to determine statistical in-between group differences in post-thaw semen parameters.

Results and discussion

The results indicated a slight improvement in acrosome integrity across all groups that were supplemented with Mito-Tempo, with the group that received 55M of Mito-Tempo showing the greatest improvement [(median of 67.99%, IQR of 5.55) compared to the control group (median of 65.33%, IQR of 7.75; P = 0.05)]. For all other sperm parameters, no significant differences (P > 0.05) were detected between different Mito-Tempo concentrations. These findings highlight the protective effect of Mito-Tempo on acrosome integrity and suggest that 55M is the most effective concentration for maintaining acrosome integrity. Since Mito-Tempo has shown a positive effect on multiple sperm parameters in other species, such as men, boars, roosters, rams, and bulls, we need to conclude that species-specificity may play a role here.

A Combination of Taurine and Caffeine in Stallion Semen Extender Positively Affects the Spermatozoa Parameters

This study was aimed to determine the impact of different taurine and caffeine combinations on the motility, viability, and oxidative markers of chilled stallion spermatozoa. Each stallion semen sample was diluted in a ratio of 1:2, with various taurine and caffeine concentrations (2.5-7.5 mg/mL taurine + 0.625-1.25 mg/mL caffeine) dissolved in a conventional extender. The control samples (CON) were prepared by diluting ejaculate only using the conventional extender. The motility was analyzed using a CASA system at different time intervals (0, 6, 12, 24, and 30 h) and the viability was evaluated using a mitochondrial toxicity test (MTT) performed at the end of the incubation at 5 °C. The liquid part of experimental samples was separated by centrifugation after 30 h of incubation and underwent the evaluation of oxidative stress via the quantification of markers ferric reducing ability of plasma (FRAP) and total oxidant status (TOS). The samples that were treated with a combination of taurine and caffeine significantly improved the motility parameters, mainly after 12, 24, and 30 h of incubation. Samples extended with combination of taurine and caffeine neither compromise viability nor alterations of redox status. The results of this study describe the combination of taurine and caffeine as an optimal supplement for improving the quality of stallion semen during chilled storage.

Inclusion of catalase in semen extender modulates the post thaw semen quality and oxidative stress profiles in mithun spermatozoa

Present study was designed to assess the effect of catalase on post-thaw semen quality parameters (SQPs), sperm kinematics, antioxidant and oxidative stress profiles and sperm cholesterol efflux in mithun (Bos frontalis). A total of 25 ejaculates were selected based on biophysical parameters and each sample was split into four equal aliquots and diluted (to get final concentration of 60 million spermatozoa per mL) with the TCG extender containing either 0 U/mL, 50 U/mL, 100 U/mL, and 150 U/mL catalase in the Group I, II, III and IV, respectively. Frozen-thawed samples were analysed for motility parameters (progressive forward and in bovine cervical mucus [BCMPT]), kinetic and velocity parameters by computer-assisted sperm analyser (CASA), viability, sperm morphological and nuclear abnormalities, acrosomal integrity, plasma membrane and nuclear integrities, sperm intra-cellular enzymatic leakage and seminal plasma biochemical (sperm cholesterol and oxidative stress markers) profiles. Study revealed an enhancement in viability, acrosomal integrity, plasma membrane integrity, motility (progressive and in cervical mucus), sperm cholesterol content and reduction in sperm morphological and nuclear abnormalities, leakage of intracellular enzymes in Group III. Moreover, intactness of acrosome and biochemical membranes were protected significantly in addition to significant improvement in kinetic and velocity profiles in extender containing 100 U/ml catalase. Correlation analysis revealed that sperm kinetic parameters, SQPs and antioxidant parameters had significant positive correlation with each other whereas these profiles were negatively correlated with sperm morphological abnormalities, enzymatic leakage and lipid peroxidation in catalase treated sperm. The results clearly indicated that inclusion of 100 U/ml catalase holds a clear advantage over control or 50 U/ml or 150 U/ml catalase in cryopreservation of mithun semen. It can be concluded from the present study that catalase supplementation in semen extender can be effectively utilized to reduce the oxidative stress and to improve the post-thaw semen quality in mithun.

A combination of taurine and caffeine maintains sperm quality in equine semen during chilled storage

Objective

The objective of this study was to evaluate the effects of caffeine and taurine on the motility and viability of chilled equine semen.

Materials and Methods

A total of 12 ejaculates were collected from three mature stallions with proven fertility during the breeding season. The gel-free spermatic fraction of each ejaculate was divided into two aliquots and diluted with a semen extender (either INRA 96® or BotuSemen Gold®). The aliquots were then split and assigned to one of the six treatment groups: control (no supplement), caffeine (2 and 4 mM), taurine (25 and 50 mM), and a combination of caffeine (2 mM) plus taurine (25 mM). Samples were stored at 4°C and analyzed at different time points (0, 24, 48, 72, and 96 h) to evaluate total (TMOT) and progressive (PMOT) motility and viability by computer-assisted sperm analysis.

Results

Regardless of the extender, PMOT and TMOT decreased over time. However, compared with the control, the treatment with 4 mM caffeine significantly mitigated the decrease in PMOT at 72 h. Additionally, semen treated with a combination of caffeine plus taurine maintained a significantly higher PMOT at 96 h, with improved viability at all time points.

Conclusions

The combination of caffeine plus taurine helps maintain chilled equine semen viability and progressive motility up to 96 h independently of the extender used.

Combined Effect of Flaxseed Oil and Vitamin E Supplementation During Bull Semen Cryopreservation on Sperm Characteristics

The present study was performed to investigate the effects of supplementing flaxseed oil (FO) or vitamin E (VE) or their combination to an extender for Simmental bull semen cryopreservation. In experiment 1, different concentrations of FO (0, 10, 100, and 1000 ng/mL) and VE (0.05, 0.1, and 0.2 mg/mL) were added to the extenders. In experiment 2, FO, VE, and FO + VE were added and a control group was included. Sperm viability, motility, motion parameters, acrosome integrity and membrane integrity, endogenous antioxidant indices, reactive oxygen species, and malondialdehyde levels were evaluated after semen thawing. A higher percentage of viability, motion parameters, endogenous antioxidant indices, and membrane integrity was observed after supplementation with 10 ng/mL FO or 0.1 mg/mL VE compared with the control group (p < 0.05). Also, combined supplementation of 10 ng/mL FO +0.1 mg/mL VE further improved the quality of frozen-thawed sperm by regulating viability, motion parameters, membrane integrity, and endogenous antioxidant indices compared with the FO or VE alone (p < 0.05). These results indicated that FO (10 ng/mL) + VE (0.1 mg/mL) could further improve the protective effects on bull sperm post-thaw.

Taurine as a Natural Antioxidant: From Direct Antioxidant Effects to Protective Action in Various Toxicological Models

Natural antioxidants have received tremendous attention over the last 3 decades. At the same time, the attitude to free radicals is slowly changing, and their signalling role in adaptation to stress has recently received a lot of attention. Among many different antioxidants in the body, taurine (Tau), a sulphur-containing non-proteinogenic β-amino acid, is shown to have a special place as an important natural modulator of the antioxidant defence networks. Indeed, Tau is synthesised in most mammals and birds, and the Tau requirement is met by both synthesis and food/feed supply. From the analysis of recent data, it could be concluded that the direct antioxidant effect of Tau due to scavenging free radicals is limited and could be expected only in a few mammalian/avian tissues (e.g., heart and eye) with comparatively high (>15-20 mM) Tau concentrations. The stabilising effects of Tau on mitochondria, a prime site of free radical formation, are characterised and deserve more attention. Tau deficiency has been shown to compromise the electron transport chain in mitochondria and significantly increase free radical production. It seems likely that by maintaining the optimal Tau status of mitochondria, it is possible to control free radical production. Tau's antioxidant protective action is of great importance in various stress conditions in human life, and is related to commercial animal and poultry production. In various in vitro and in vivo toxicological models, Tau showed AO protective effects. The membrane-stabilizing effects, inhibiting effects on ROS-producing enzymes, as well as the indirect AO effects of Tau via redox balance maintenance associated with the modulation of various transcription factors (e.g., Nrf2 and NF-κB) and vitagenes could also contribute to its protective action in stress conditions, and thus deserve more attention.

Role of Antioxidants in Cooled Liquid Storage of Mammal Spermatozoa

Cooled preservation of semen is usually associated with artificial insemination and genetic improvement programs in livestock species. Several studies have reported an increase in reactive oxidative species and a decrease in antioxidant substances and sperm quality parameters during long-term semen storage at refrigerated temperatures. The supplementation of antioxidants in extenders before refrigeration could reduce this detrimental effect. Various antioxidants have been tested, both enzymatic, such as superoxide dismutase and catalase, and non-enzymatic, such as reduced glutathione, vitamins E and C and melatonin. However, the problem of oxidative stress in semen storage has not been fully resolved. The effects of antioxidants for semen-cooled storage have not been reviewed in depth. Therefore, the objective of the present study was to review the efficiency of the supplementation of antioxidants in the extender during cooled storage of semen in livestock species.

Melatonin improves the motility and DNA integrity of frozen-thawed ram spermatozoa likely via suppression of mitochondrial superoxide production

The ability of the neurohormone melatonin to ameliorate cryopreservation-induced damage to spermatozoa has been demonstrated in several domestic species. However, it is unclear how these protective effects are conferred, with improvements in sperm quality ambiguously attributed to the general antioxidant activity of melatonin. To further investigate this phenomenon, ram spermatozoa were diluted in cryomedia with and without melatonin (0 [control], 0.1, 1, 10, and 100 μM) and assessed for motility, viability, DNA integrity, mitochondrial superoxide production, lipid peroxidation, and intracellular reactive oxygen species before freezing and after thawing (0, 3, and 6 h post-thaw). Before freezing, supplementation with melatonin at any concentration had no effect on any measure of sperm quality. However, post-thaw, spermatozoa frozen in the presence of any level of melatonin reduced mitochondrial superoxide production of spermatozoa (P < 0.001), decreased the level of sperm DNA fragmentation (P < 0.001), and increased the percentage of motile spermatozoa (P = 0.035). Melatonin supplementation did not influence the relative levels of lipid peroxidation in the sperm membrane, the levels of intracellular reactive oxygen species, or sperm membrane lipid disorder (P > 0.05). There was no difference in the percentage of viable spermatozoa between treatment groups pre- or post-freeze (P > 0.05). These results suggest that, in the ram, melatonin does not protect the quality of cryopreserved spermatozoa through a nondiscerning scavenging of reactive oxygen species as previously suggested. Rather, melatonin appears to specifically reduce mitochondrial superoxide production, altering sperm functionality, as opposed to merely increasing the percentage of live sperm.

Effect of melatonin on bovine sperm characteristics and ultrastructure changes following cryopreservation

The production of reactive oxygen species (ROS) during cryopreservation of semen alters the sperm motion and mobility characteristics, resulting in poor or failure of conception rate after artificial insemination (AI). Melatonin an antioxidant is able to modulate the effect of ROS and prevents spermatozoa by reducing the oxidative stress during freezing process. Eight ejaculates from eight healthy HF bulls diluted with Tris egg yolk glycerol extender were divided into five equal aliquots. The Computer Assisted Semen Analyser (CASA) results showed no significant difference between the control-post- thaw samples and melatonin-treated samples; however, the velocity of spermatozoa with regard to the VAP, VSL showed highest increase in the 0.25 mM MLT-treated semen followed by 0.1 mM MLT treated semen except for VCL where velocity increased with increase in the concentration of melatonin. The vigour of spermatozoa regard to BCF, STR and LIN recorded highest increase in the 0.25 mM MLT treated semen followed by 0.1 mM MLT-treated semen except for the ALH where vigour increased with increase in the concentration of melatonin. The electron micrography images illustrated that the addition of 0.1 mM melatonin protected the plasma membrane and acrosome region and maintained the ultrastructure integrity of the cryopreserved spermatozoa when compared to control group, whereas the electron micrography of spermatozoa treated with 0.2 and 0.25 mM melatonin illustrated highest damage to the plasma and acrosome membrane. Thus concluding that inclusion of melatonin to sperm extender can improve the post-thaw quality of cryopreserved bull spermatozoa.

The anti-oxidant roles of Taurine and Hypotaurine on acrosome integrity, HBA and HSPA2 of the human sperm during vitrification and post warming in two different temperature

Despite advances in vitrification techniques for sperm cryopreservation, cryo-damages of sperm caused by generation of reactive oxygen species (ROS) continue to impede implementation of this technique. This study analyses the effects of taurine and hypotaurine as anti-oxidants during vitrification of human sperms. The study was performed in two steps. In the first step, 20 normospermic semen samples were vitrified in the presence of varying concentrations of taurine and hypotaurine, and their effects as anti-oxidant agents on classical sperm parameters, hyaluronan-binding assay (HBA), lipid peroxidation (LPO) and acrosome reaction (AR) were studied. Statistical analyses showed that the sperm parameters in all vitrified groups decreased significantly (P < 0.05) compared to the fresh group. However, HBA and acrosome integrity in vitrified groups containing taurine and 50 mM of hypotaurine were better than in the control group (P < 0.05). The morphology of the vitrified group was good only in the group that contained 50 mM of hypotaurine (P < 0.05). Based on the results from the first step, 50 mM of hypotaurine was considered the ideal anti-oxidant formulation and further tests were carried out on 10 normospermic semen samples with this protecting agent. In addition to the mentioned parameters, the expression of heat shock proteinA2 (HSPA2) was studied in the vitrified group with 50 mM hypotaurine, warmed under two different warming temperatures 37 and 42 °C. 50 mM Hypotaurine was found to equally improve motility, morphology, HBA, and AR after warming at 37 °C and 42 °C (P < 0.05). However, at both warming temperatures, the expression of HSPA2 was reduced in all vitrified groups comparing to the fresh group (P < 0.05). In conclusion, taurine and hypotaurine antioxidants, especially 50 mM hypotaurine, are able to reduce deleterious cryo-injuries on morphology, acrosome and HBA and improve sperm recovery at both warming temperatures (37 and 42 °C). However, they do not have any protective action on expression of HSPA2.

Pelvimetric profiles in crossbred cows of Andaman and Nicobar Islands

A study was conducted in crossbred cows maintained atorganised dairy farm of the institute to select cows based on the external pelvimetric measurements associated with body weight for breeding purpose. Cows (32) selected were divided in to 4 groups based on age, viz. Gr I (24–36 months), Gr II (37–48 months), Gr III (49–53 months), Gr IV (>53 months) with 8 cows in each group. Overall mean area of pelvic inlet and outlet was 235.61±4.74 and 147.90±5.21 cm2, respectively. The study concluded that pelvimetric parameters and body weight were significantly higher in Gr IV than other younger animals (Gr I, II and III). These pelvimetric parameters and body weight increased as age advanced and differed significantly between the age groups. The body weight was positively correlated with pelvic area (r=0.92) and age (r=0.88). These findings will be helpful in selection of crossbred cows for breeding purpose in Andaman and Nicobar Islands.

Efeito de diferentes concentrações de melatonina em espermatozoides de carneiros sobre estresse oxidativo após criopreservação

Resumo: Objetivou-se avaliar o efeito da adição de diferentes concentrações de melatonina no sêmen diluído de carneiros após criopreservação. Foram coletados 10 ejaculados de três carneiros adultos (n=30), por meio de vagina artificial para ovinos. Os ejaculados coletados foram diluídos em Tris-Gema de ovo, para a concentração final de 200x106 sptz/mL, mantidos em banho maria a 32°C, e a melatonina adicionada conforme os tratamentos: Controle; 100pM; 100nM; 100μM e 1mM de melatonina. Então, as amostras foram resfriadas em câmara fria a 5°C por duas horas, envasadas em palhetas de 0,5 mL e lacradas. Logo após, foram acondicionadas sob vapores do nitrogênio liquido, por 15 minutos, a 8cm da lâmina líquida e congeladas com nitrogênio líquido. As amostras foram analisadas quanto à motilidade espermática, integridade da membrana plasmática, membrana acrossomal, atividade mitocondrial, quantificação do estresse oxidativo e a capacidade de ligação. As variáveis foram submetidas à análise de variância e as médias foram comparadas pelo teste de Tukey a 5% de probabilidade. A motilidade total e progressiva dos espermatozoides descongelados foi maior nas amostras tratadas com 100pM de melatonina (62,99 e 45,07% respectivamente; P<0,05) quando comparado aos demais tratamentos. A adição das diferentes concentrações de melatonina no sêmen diluído, com exceção da concentração de 1 mM, apresentou maior percentual de células com membrana plasmática íntegra, quando comparadas com o controle (P<0,05). O percentual de espermatozoides com integridade da membrana do acrossoma foi maior no sêmen tratado com 100 pM de melatonina (P<0,05) do que nos demais tratamentos. A alta atividade mitocondrial foi maior nos espermatozoides tratados com 100 pM de melatonina (69,30%; P<0,05). A adição de 100 nM de melatonina reduziu a quantidade de TBARS após a criopreservação (2,84; P<0,05) quando comparado aos demais tratamentos. Após o descongelamento, o número de espermatozoides que se ligaram à membrana perivitelina foi maior nos tratados com 100 pM de melatonina (155,73; P<0,05). Portanto, a adição de melatonina no sêmen diluído pode ser útil para aperfeiçoar a criopreservação do sêmen de ovinos, melhorando as taxas de fertilização por meio da inseminação artificial.

Effect of sperm concentration on characteristics and fertilization capacity of rooster sperm frozen in the presence of the antioxidants catalase and vitamin E

The objective of this study conducted was to determine the influence of different levels of sperm concentration, including catalase (CAT) and vitamin E (VitE) in rooster semen extender on postthawed quality and fertility of rooster semen. Semen was collected twice a week from six roosters (Arian) and diluted according to experimental treatments consisting of sperm suspensions containing different sperm concentrations (200, 400, and 600 × 106 sperm/mL) without antioxidant supplementation as control (Con) groups (Con200, Con400, and Con600, respectively), sperm suspensions containing different sperm concentrations (200, 400, and 600 × 106 sperm/mL) supplemented with 5-μg/mL VitE (VitE200, VitE400, and VitE600, respectively) and different sperm concentrations (200, 400, and 600 × 106 sperm/mL) supplementation with 100 IU/mL CAT (CAT200, CAT400, and CAT600, respectively). After thawing; sperm motility, membrane integrity, and mitochondrial function were assessed. Fertility and hatchability rates were determined by using 100 artificially inseminated hens. The percentage of total motility (TM) and activity of mitochondria decreased (P < 0.05) as the sperm concentration increased in control groups. So, the lowest percentage of the TM and activity of mitochondria were observed in the Con600 as compared with other treatment groups. Extenders containing 100 IU/mL CAT and 5-μg/mL VitE resulted in higher (P < 0.05) TM, progressive motility, membrane integrity, and activity of mitochondria compared with control groups. Adding VitE and CAT in different sperm concentrations, the percentage of TM, membrane integrity, and activity of mitochondria decreased (P < 0.05) as the sperm concentration decreased. The highest (P < 0.05) membrane integrity, TM, and progressive motility were recorded at VitE400 and CAT400. Including VitE and CAT in rooster extender with different level sperm concentrations had no effect (P > 0.05) on fertility and hatchability rates. In conclusion, although adding VitE and CAT in extender with different levels of sperm concentration improved postthawed quality of rooster semen, but adding VitE and CAT in the extender have no effect on fertility rate.

Royal jelly supplementation in semen extender enhances post-thaw quality and fertility of Nili-Ravi buffalo bull sperm

Two experiments were conducted to evaluate the effect of royal jelly (RJ) on post-thaw sperm quality, in vitro and in vivo fertility rate of cryopreserved buffalo bull sperm. The semen was collected from three mature regular donor buffalo bulls, ejaculates were pooled and semen evaluated initially. In Experiment 1, the ejaculates were extended in tris-citric acid diluter supplemented with different RJ concentrations (0, 0.05, 0.1, 0.2, 0.3 or 0.4%). The diluted semen was cooled to 4°C, packaged into 0.5 mL straws and frozen using standard procedure. The straws were thawed and assessed for sperm progressive motility, viability, plasma membrane, acrosome, and chromatin integrity. The results indicated that sperm progressive motility was significantly greater (P<0.05) in 0.05, 0.1, 0.2 and 0.3% RJ than 0.4% RJ supplemented and control groups. The sperm viability, plasma membrane and acrosome integrity were significantly improved (P<0.05) in 0.1% RJ supplemented group the compared to other treatment groups. In Experiment 2, cryopreserved sperm with 0.1% RJ supplementation and control (without RJ supplementation) were used to observe the in vitro fertilizing potential and in vivo fertility. In vitro fertilization method was applied to assess the cleavage rate; whereas, AI was performed in buffalo during in vivo fertility trial. The buffaloes were inseminated 12h after standing estrus and pregnancy diagnosis was performed through ultrasonography. The results revealed that the cleavage rate was higher (P<0.05) in 0.1% RJ as compared to control group. However, the pregnancy rate was similar (P>0.05) between 0.1% RJ supplemented and control groups. It is concluded that supplementation of RJ in freezing extender can improve the cryosurvival rate and in vitro fertilizing capacity of buffalo bull sperm.

The Relationship between Seminal Melatonin with Sperm Parameters, DNA Fragmentation and Nuclear Maturity in Intra-Cytoplasmic Sperm Injection Candidates

Objective

Melatonin, the chief secretory product of the pineal gland, regulates dynamic physiological adaptations that occur in seasonally breeding mammals as a response to changes in daylight hours. Because of the presence of melatonin in semen and the mem- brane melatonin receptor in spermatozoa, the impact of melatonin on the regulation of male infertility is still questionable. The aim of this study was to determine the effects of endogenous melatonin on human semen parameters (sperm concentration, motility and normal morphology), DNA fragmentation (DF) and nuclear maturity.

Materials and Methods

In this clinical prospective study, semen samples from 75 infer- tile men were routinely analyzed and assessed for melatonin and total antioxidant capac- ity (TAC) levels using the enzyme-linked immunosorbent assay (ELISA) and colorimetric assay kits, respectively. DF was examined by the sperm chromatin dispersion (SCD) test. Acidic aniline blue staining was used to detect chromatin defects in the sperm nuclei.

Results

There was no significant correlation between seminal plasma melatonin and TAC with sperm parameters and nuclear maturity. However, we observed a positive significant correlation between DF and melatonin level (r=0.273, P<0.05).

Conclusion

Melatonin in seminal plasma is positively correlated with damaged sperm DNA of infertile patients. The mechanism of this phenomenon needs further study.

Effect of Superoxide Dismutase on Semen Parameters and Antioxidant Enzyme Activities of Liquid Stored (5°C) Mithun (Bos frontalis) Semen

The present study was undertaken to assess the effect of superoxide dismutase (SOD) on sperm motility, and viability; total sperm abnormality; acrosomal and plasma membrane integrity; DNA abnormality; antioxidant profiles such as catalase (CAT), reduced glutathione (GSH), and total antioxidant capacity (TAC); enzymatic profiles such as aspartate amino transaminase (AST), and alanine amino transaminase (ALT); and biochemical profiles such as malondialdehyde (MDA) production and cholesterol efflux. Total numbers of 50 ejaculates were collected twice a week from eight mithun bulls and semen was split into four equal aliquots, diluted with the TEYC extender. Group 1: semen without additives (control), and group 2 to group 4: semen was diluted with 50 U/mL, 100 U/mL, and 150 U/mL of SOD, respectively. These seminal parameters, antioxidant, enzymatic, and biochemical profiles were assessed at 5°C for 1, 6, 12, 24, and 30 h of incubation. Inclusion of SOD into diluent resulted in significant (P<0.05) decrease in percentages of dead spermatozoa, abnormal spermatozoa, and acrosomal abnormalities at different hours of storage periods as compared with control group. Additionally, SOD at 100 U/mL has significant improvement in quality of mithun semen than SOD at 50 or 150 U/mL stored in in-vitro for up to 30 h. It was concluded that the possible protective effects of SOD on sperm parameters are that it prevents MDA production and preserves the antioxidants and intracellular enzymes during preservation.