Seminal Plasma pH Research Articles

Physiological evaluation of seasonal sperm quality in a biannual spawner, Pacific abalone: Effects on in-vitro fertilization and cryotolerance

Pacific abalone, Haliotis discus hannai, is a highly valuable gastropod mollusk commonly found in Southeast Asia. The present study aims to analyze the seminal plasma quality, sperm quality, and cryotolerance of the Pacific abalone sperm during its reproductive season. The seminal plasma quality was evaluated by analyzing biochemical and metabolite composition, enzymatic activity (superoxide dismutase, catalase, and glutathione), and lipid peroxidation (LPO) activity. The sperm quality was evaluated by analyzing motility, concentration, volume, ATP content, acrosome integrity (AI), plasma membrane integrity (PMI), mitochondrial membrane potential (MMP), DNA integrity, and fertilization potential. The cryotolerance capacity was evaluated by analyzing post-thaw motility, AI, PMI, MMP, and DNA integrity. Seminal plasma osmolarity was significantly higher (1123.3 ± 1.5 mOsmL-1) in May compared to other reproductive periods, with Cl- (516.8 ± 0.5 mM) and Na+ (460.2 ± 0.4 mM) as the dominant ions. The seminal plasma pH remained constant at 6.8 throughout the reproductive season. Improved enzymatic activity and lower LPO were detected in May or June. Sperm quality indicators were similar in May and June, except for sperm production. The fertilization potential (May: 93.0 ± 4.4%, June: 86.0 ± 7.2%) and hatching rate (May: 86.6 ± 5.78%, June: 82.3 ± 3.2%) of Pacific abalone were significantly higher in May or June than they were in other reproductive seasons. The motility (May: 50.19 ± 2.35%, June: 49.96 ± 1.60%), AI (May: 44.02 ± 3.46%, June: 42.16 ± 3.61%), PMI (May: 54.12 ± 3.29%, June: 52.82 ± 2.58%), and MMP (May: 44.02 ± 3.46%, June: 42.16 ± 3.61%) of the cryopreserved sperm were similar in May and June compared with those preserved in other reproductive seasons. The DNA integrity of the cryopreserved sperm was similar in May (80.3 ± 6.7%) or June (78.9 ± 7.4%) and had a higher cryotolerance than in other reproductive seasons. Hence, it can be suggested that May and/or June are suitable periods for sperm physiology experiments, artificial reproduction, and sperm cryopreservation of Pacific abalone.

Effect of Electroejaculation Protocols on Semen Quality and Concentrations of Testosterone, Cortisol, Malondialdehyde, and Creatine Kinase in Captive Bengal Tigers

The Bengal tiger (Panthera tigris tigris) is critically endangered, so assisted reproductive technologies, including artificial insemination, are important conservation tools. For wild and domestic felids, electroejaculation (EE) is the most common semen collection method, with protocols optimized to obtain sufficient amounts of viable sperm for artificial insemination. However, less attention has been paid to ensuring animal wellbeing during the process. This study examined the effects of three EE protocols (Low, 2–5 volts; Medium, 3–6 volts; High, 4–7 volts) on semen quality, testicular size, serum testosterone, creatine kinase (CK), and malondialdehyde (MDA) concentrations, and serum cortisol as a proxy for stress. Blood samples were collected before, during, and after each EE series. Seminal plasma pH, and sperm motility, viability, and morphology were evaluated after each procedure. Seminal plasma and sperm pellet MDA concentrations were also determined. Primary sperm abnormalities and seminal plasma MDA were higher in the Low compared to Medium and High voltage groups (p < 0.05). Serum CK in the High voltage group increased during the EE series (p < 0.05), suggesting the potential for muscle damage. However, no significant changes were observed for serum cortisol, testosterone, or MDA concentrations. Results suggest the Medium voltage protocol produced good quality samples at lower voltages than the High protocol with no negative effect on muscle function, which might be better for animal welfare.

Effects of dietary supplementation of multi-strain probiotics on semen quality, seminal plasma compositions, and fertilization ability of rainbow trout (Oncorhynchus mykiss) broodstock spermatozoa

The present experiment aims to study the effects of dietary multi-strain probiotics on semen quality, seminal plasma compositions, and fertilization ability of male rainbow trout. For this purpose, a total of 48 broodstocks with an average initial weight of 1366.1±33.8g were divided into 4 groups and 3 replicates. Fish were fed with diets containing 0 (control), 1×109 (P1), 2×109 (P2), and 4×109 (P3) CFU probiotic kg-1 diet for 12 weeks. Results showed that dietary supplementation of probiotics significantly increased plasma testosterone level, motility time of spermatozoa, sperm density, and spermatocrit value in P2 and P3 treatments and Na+ level in P2 treatment compared to the control group (P<0.05). The activities of aspartate aminotransferase and lactate dehydrogenase had significantly decreased in the P2 treatment compared to the control group (P<0.05). No considerable variations were observed between control fish and treatment groups (P>0.05) in semen biochemical parameters, percentage of motile spermatozoa, osmolality, and pH of seminal plasma. Based on the results, the highest fertilization rate (97.2±0.9%) and eyed egg survival (95.7±1.6%) were observed in the P2 treatment, and those values showed remarkable differences with the control group (P<0.05). The results indicated that multi-strain probiotics have potential efficacy on semen quality and fertilization ability of rainbow trout broodstock spermatozoa.

Ionic control of sperm motility and trials for the improvement of pufferfish (Takifugu alboplumbeus) sperm extenders

Seminal plasma characteristics, such as ionic composition and pH, are important for sperm maturation and further motility. In this work, a first batch of experiments evaluated the effect of the absence of several ions (Na+, K+, Mg2+) in the artificial seminal plasma, as well as the effect of artificial seminal plasma pH and seawater pH, on the sperm activation in the pufferfish (Takifugu alboplumbeus, named before Takifugu niphobles). In all the experiments, total motility, progressive motility, curvilinear velocity, straight line velocity, and average path velocity were measured. The absence of Na+, K+ or Mg2+ ions did not reduce the sperm motility in comparison with the control. In contrast, artificial seminal plasma pH had a strong effect on sperm motility. Samples diluted in artificial seminal plasma at pH 6.5 showed a high reduction of sperm motility in comparison with higher pHs (7.5, 8.5 and 9.5), and this inhibition was reversible. Where the effect of the pH of artificial seawater in sperm motility (used as activation medium) was concerned, there were no significant differences between the control (pH 8.2) and pH 6.5, indicating that pufferfish spermatozoa can swim in acidic environments. Finally, nigericin (that make equal the intracellular pH and extracellular pH) was added, and the highest sperm motility was found at pH 7.0, which suggested that the optimal intracellular pH of pufferfish for sperm motility is 7.0.Our second batch of experiments was developed to optimize the pufferfish sperm extenders to achieve longer preservation under refrigeration, assessing the addition of several concentrations of magnesium and NaHCO3 (used in extenders for other fish species), as well as different pHs. From the extender experiments it was observed that bicarbonate reduced the sperm motility after 7 days of incubation, and it can be concluded that the use of magnesium 2 mM as part of the extender composition, in combination with the pH measured in the pufferfish sperm (7.5), seems to be the best option for the short-medium term storage of the sperm of this species.

Seasonal changes in the milt quality of spotted scat, Scatophagus argus: Implications for artificial propagation

The current study investigated the correlation among sperm production (milt volume, spermatocrit and sperm count), sperm motility characters and biochemical composition of seminal plasma during different seasons to estimate the quality of semen in the Spotted scat (Scatophagus argus). The sperm of 120 males were collected over a period of 2 years seasonally viz., summer, pre-monsoon, monsoon and post-monsoon. During the collection period, it was observed that there were significant (p < 0.05) seasonal variations in the semen quality including sperm motility and production more in the summer season than other seasons. The osmolality of seminal plasma varied from 343.33 to 370.33 mOsm/kg. The pH of seminal plasma elevated from 7.37 to 7.63 during monsoon and summer seasons. The motility of S. argus sperms correlated with the concentration of biochemical compounds viz., Ca2+, Mg+ and Cl− during the summer season. Based on the present observation it could be highlighted that sodium and potassium were negatively correlated (p < 0.01 and p < 0.05) effect on total protein (r = −0.826; −0.956), glucose (r = −0.819; −0.717), cholesterol (r = −0.978; −0.849), AST (r = −0.853; −0.897), ALT (r = −0.970; −0.967), calcium (r = -0.850; −0.697), magnesium (r = −0.852; −0.843) and chloride (r = −0.906; −0.926). In conclusion, many physical and biochemical compositions of S. argus semen improved during that the summer and pre-monsoon season as compared to that of monsoon and post-monsoon. Fertility tests were performed to determine the ability of spermatozoa to fertilize an egg. Highest fertilization (79.92 ± 4.60%) and hatching (80.75 ± 3.89%) rates were observed during summer, while the rates were lowest during monsoon (40.50 ± 4.52%; 53.92 ± 7.38%). This work forms a compiled data for standard semen quality, which in turn will help to select good milters for hatchery production, cryopreservation and assisted breeding programs of this fish.

Spermatology and sperm ultrastructure in farmed coho salmon (Oncorhynchus kisutch)

Fish sperm quality assessment is an essential process for commercial production. The goal of this study was to evaluate the quality of fresh milt of farmed coho salmon using a functional and structural approach. A total of 37 males were used to determined parameters such as sperm concentration, pH and osmolality of seminal plasma, viability, mitochondrial membrane potential and fertility. In addition, ultrastructure and morphology were assessed through transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The results show that coho salmon release a large volume of milt (55.08 mL ± 20.14 mL) with a mean concentration of 13.45 ± 3.40 × 109 spermatozoa mL−1. A positive correlation was found between sperm concentration and spermatocrit (P < 0.05; r = 0.8447). Milt contained a high percentage of motile sperm (85.00–95.00%) with a mean motility period of 45.25 ± 2.56 s, viability of 95.24 ± 2.60% and mitochondrial membrane potential of 91.33 ± 4.03%. The fertility rate was also high (96.00 ± 4.16%). SEM and TEM images revealed that mature spermatozoa of coho salmon have a total length of 32.85 ± 1.25 μm, are anacrosomal, and consist of an ovoid head, a short cylindrical mid-piece and a long flagellum which can be differentiated into a long main-piece and a short end-piece. The posterior part of the nucleus contains the nuclear fossa in which are located the distal and proximal centrioles, perpendicular to each other. There is only one mitochondrion, positioned as a ring in the mid-piece. The flagellum has two lateral side-fins, apparently of unequal length, and shows the typical “9 + 2” axoneme. These findings indicate that most of milt and sperm traits are within the range reported for other salmonids. Similarly, the results of morphology and ultrastructure are consistent with other salmonids, especially rainbow trout and brown trout.

Sperm cryopreservation of Prochilodus lineatus throughout the same reproductive season

The aim of this study was to determine the effect of seasonality on post-thaw sperm quality in Prochilodus lineatus. Sperm from 43 males was cryopreserved throughout the reproductive season (November–March). Fresh sperm quality, concentration, volume, seminal plasma pH, osmolality and ion concentration were analysed. Post-thaw sperm was analysed for its motility rate, velocities, beat-cross frequency, cell morphology, oxidative stress and fertilization capacity. Prochilodus lineatus fresh sperm yielded high-quality during the reproductive period (motility >80%). Post-thaw sperm quality changed throughout the season, with higher motility (63.2%–72.3%) and curvilinear velocity (VCL) (55.9–59.2 µm/s) from December to March. Sperm concentration was negatively correlated with post-thaw sperm motility and VCL, and positively correlated with seminal plasma Ca2+ concentration, catalase activity (CAT) and reactive oxygen species (ROS). Seminal plasma Ca2+ was positively correlated with ROS and negatively correlated with post-thaw sperm motility. Post-thaw sperm CAT and fertility correlated positively. Although post-thaw sperm quality was reduced in November, the increased CAT was efficient in maintaining its fertilization capacity. In order to face seasonal influence, the optimal period to cryopreserve P. lineatus spermatozoa is from December to March, when sperm exhibits characteristics which make spermatozoa more prone to resist cryodamage.

Effects of Cryopreservation on Gene Expression and Post Thaw Sperm Quality of Pacific Abalone, Haliotis discus hannai

Pacific abalone, Haliotis discus hannai, is a high commercial seafood in South-East Asia. The aim of the present study was to determine effects of cryopreservation on gene expression and post thaw sperm quality of Pacific abalone. Two ions, Na+ (459.1 ± 3.1 mM) and Cl– (515.9 ± 1.1 mM), were predominant in the seminal plasma (pH: 6.8 ± 0.1; osmolarity: 1,126 ± 3 mOsmL–1). Cryopreservation reduced mRNA expression levels of protein kinase A (PKA-C) and heat shock proteins (HSP70 and HSP90) genes in sperm. Fluorescent technique was used to compare morphological defects, acrosome integrity (AI), plasma membrane integrity (PMI), mitochondrial membrane potential (MMP), and DNA integrity of sperm cryopreserved with five different cryopreservation solutions (8% Me2SO, 8% EG, 6% PG, 2% GLY, and 2% MeOH). Droplet in tail and coiled tail defects was not observed for sperm cryopreserved with 8% Me2SO or 2% GLY. Sperm cryopreserved with 8% Me2SO showed improved DNA integrity and lower cryodamage than sperm cryopreserved with other cryoprotectants. Sperm to egg ratio of 10,000:1 was found to be the most suitable ratio for in vitro fertilization among different ratios tested. The fertilization rate of sperm cryopreserved with 8% Me2SO was not significantly (p &amp;gt; 0.05) different from that of sperm cryopreserved with 2% GLY. DNA fragmentation showed strongly negative relationships with sperm quality parameters. Sperm cryopreserved with 8% Me2SO showed higher post thaw quality and mRNA expression of sperm motility associated gene than those cryopreserved with other cryoprotectants. The present research suggests to use 8% Me2SO for cryopreservation of Pacific abalone sperm as well as for hatchery production.

Comparison of milt and blood parameters including testosterone and gonadotropins levels of sex‐reversed female rainbow trout ( Oncorhynchus mykiss ) by different steroid hormones

All-female progeny is preferable in the reproduction of rainbow trout. Using sex-reversed (SR) female rainbow trout by steroid hormones as broodstock in the reproduction is the most appropriate way to all-female progeny. This study compared mature SR female rainbow trout by ethisterone (ET), 11β-Hydroxyandrostenedione (HD) and 17α-Methyltestosterone (MT) in terms of spermatological parameters and health status, for the first time. Spermatozoa concentration, motility characteristics, seminal plasma pH, testosterone and gonadotropins in seminal plasma and blood serum, blood parameters of SR females were evaluated, comparing with testicular and stripped milt, and blood from normal males (NM). The SR females by HD had greater gonadosomatic index and better motility characteristics compared with other groups. Also, blood parameters of this group were more similar to those in NM. The SR females by ET had the lowest haematocrit and the highest glucose and activities of the enzymes compared with the other groups. The measured hormones were significantly the lowest in both seminal plasma and serum of the ET group. These findings suggested that using of HD for obtaining SR female should be preferred due to having the better quality spermatozoa and health status.

Toward controlled breeding of the blackfin icefish Chaenocephalus aceratus (Lönnberg 1906): determination of spermatozoa concentration and evaluation of short- and long-term preservation of semen

Efforts to study the effects of environmental change on early development of Antarctic fishes would benefit from the ability to control reproduction by in vitro fertilization. Here, we established a spectrophotometric method to determine spermatozoa concentration in the semen of the blackfin icefish Chaenocephalus aceratus and we evaluated the potential for short (refrigeration) and long-term (cryopreservation) storage. The former will maximize the use of semen over several hours and the latter alleviate the risk that semen is unavailable when a spawning female is available. Seminal plasma osmolality and pH of GnRH-injected male semen were 423.65 ± 35.6 mOsm kg−1 and 8.05 ± 0.11, respectively. The predictive power of regression models between spermatozoa concentration and absorbance was determined from 200 to 600 nm and revealed a best-fitted correlation at 505 nm. The standard curve was tested against measured concentrations and the average difference between measured and estimated concentrations was 0.27 ± 10.23%. Semen could be kept on ice for up to 6 h with minimal loss ( 90% post-thawing motility using a salt-based extender (pH 7.5–7.85 and ~ 280 mOsm kg−1) and 10% DMSO after 72 h immersed in liquid nitrogen. Spermatozoa morphometry revealed significant inter-individual variability. Average head length, head width, and flagella length were 3.78 ± 1.03, 2.87 ± 0.78, and 17.75 ± 7.15 µm, respectively. Spermatids composed 9.7 ± 0.8% of total spermatogenic cells, probably indicating active spermatogenesis, but perhaps resulting to some degree from the semen extraction technique used. Variations on these baseline methods may facilitate semen preservation and ultimately in vitro fertilization in this and other notothenioid species, thereby enhancing our understanding of the responses of early-life stages of Antarctic fishes to future warming of the Southern Ocean.

Effects of constant and changing water temperature on sperm quality of the endangered Çoruh trout, Salmo coruhensis

ABSTRACT In this study, the cumulative influence of male acclimation temperature on sperm quality of the Çoruh trout Salmo coruhensis was compared during the sperm production period. Broodstocks were kept in constant (12.8ºC), and changing (8.4ºC to 12.8ºC) water temperature using well water and stream water until first spawning and sperm quality traits were compared. 20 individuals three-year-old males with a mean weight of 2147 ± 647 g and a mean length of 56 ± 2 cm were used for the two groups in this study. Total sperm motility (%), progressive motility (%), sperm volume (ml), seminal plasma pH, osmolality (mOsm/kg), spermatozoa concentration (cells/ml), and spermatozoa duration (sec) were investigated. Total sperm motility (96.40% ± 25.06) and sperm volume (13 ± 5.97 ml) in the stream water group were significantly higher than in the well water group (82.68% ± 11.52 and 6.2 ± 2.48 ml) (P < .05). These results indicate that S. coruhensis prefers changing and colder stream water during the sperm production period to produce a good quality gamete.

Effects of seminal plasma ionic content, pH and osmolality on spermatozoa motility in bester (Female Huso huso × Male Acipenser ruthenus) sturgeon

The ionic contents, pH and osmolality of seminal plasma and their relationships to sperm motility indices (sperm motility duration and percentage of motile sperm) were evaluated in bester. Semen was collected from six bester specimens and their seminal plasma was evaluated. The seminal plasma contained 54.5±2.8 mM sodium, 22.33±2.5 mM chloride, 7.1±1.2 mM potassium, 3.55±0.6 mM calcium and 0.58±0.09 mM magnesium. The result shows that Na+, Cl- and K+ (54.5±2.8, 22.33±2.5 and 7.1±1.2 mM, respectively) were predominant ions in bester seminal plasma like other sturgeons. However the concentrations of K+, Ca2+ and Cl- in bester seminal plasma were higher than those reported in beluga and sterlet as parental species. The mean pH and osmolality of seminal plasma were 8.09±0.34 and 127.6±20.8 mOsm kg-1, respectively. A significant negative regression was observed between osmolality and percentage motility (r=- 0.893).

Sperm quality in fish: Determinants and affecting factors

Fish sperm quality assessment is helpful for optimizing production and for monitoring the environmental state. Sperm can be monitored relatively easy and, to date, various analyses have been applied and proven to be helpful in this task. Among them, sperm motility parameters such as sperm speed are one of the main performance traits during assisted fish reproduction. Apart from motility the sperm concentration, volume, and seminal plasma pH and osmolality are also frequently evaluated and are the main sperm quality indicators measured in fish sperm. However, other parameters also determine sperm fertilization potential. Recent knowledge reveals several additional parameters of high importance for sperm function. Among them are DNA integration, membrane stability, mitochondria status and enzymatic activity. Measuring all these parameters in fish sperm provides complex knowledge regarding male fertility and helps to improve broodstock maintenance protocols as well as gamete handling and fertilization processes. This review focuses on the presentation of the sperm quality measures for freshwater and marine species of the fish and provides information regarding recent methods of sperm quality evaluation.

Sperm Quality and Seminal Biochemical Parameters in Infertile Men with and without Leukocytospermia

Objective: White Blood Cells (WBC) are commonly present in almost every human semen sample, but the clinical significance of leukocytospermia, defined as more than 1 × 106/mL of WBC in seminal plasma, is not elucidated. The aim of this study was to evaluate the association of the leukocytospermia with sperm characteristics and biochemical markers of function of the male accessory glands in infertile men. Methods: One hundred and eighty-five men with fertility problems were investigated. They were composed of two groups, patients without leukocytospermia (n=115) and patients with leukocytospermia (n=70). The infertile men enrolled in the study underwent semen analysis and measurements of fructose, acid-phosphatase, zinc and γ- glutamyltranspeptidase in seminal plasma. Results: The mean age of study participants was 33.97 ± 6.45 years. The analysis of leukocyte concentration in semen has shown that 70 (37.8%) patients had leukocytospermia. Patients with leukocytospermia had significantly decreased sperm count and vitality while other sperm parameters such as seminal volume, progressive motility, morphology of pathological forms and seminal plasma pH were not affected. The levels of acid-phosphatase, fructose and γ-glutamyltranspeptidase were significantly decreased in infertile men with leukocytospermia compared to men without this condition. The levels of seminal zinc did not differ between the two groups of patients. Conclusion: Our results indicate that leukocytospermia has a significant negative effect on the standard semen parameters and biochemical compounds that reflect the function of accessory glands, prostate and seminal vesicles in particular.

Sperm and seminal plasma proteomics of high- versus low-fertility Holstein bulls

Sperm are highly specialized compartmentalized cells, with unique compositional, morphological and functional properties, including a plasma membrane that undergoes dynamic protein remodeling and surface modifications. Seminal plasma is a highly complex biological fluid containing proteins, amino acids, enzymes, fructose and other carbohydrates, lipids, major minerals and trace elements. Seminal plasma proteins are involved in regulation of osmotic pressure and pH of seminal plasma, transport of ions, lipid and hormones. The objective was to compare sperm and seminal plasma proteomes of bulls with differing fertility and to relate differences to biological processes. Semen was collected from bulls with high or low fertility (4 bulls in each category). Sperm and seminal plasma proteins were isolated, purified, subjected to 2-D gel electrophoresis, protein identification and ontology. In sperm and seminal plasma, binder of sperm proteins (BSP)-1, −3 and −5, and spermadhesin-1, ALB, TIMP, AKI and PEBP1 were higher for high-versus low-fertility bulls (P < 0.05), whereas proteins CLU, CCT5 and 8, ELSPbP1, and PSMA6 were more abundant in sperm and seminal plasma of low- versus high-fertility bulls (P < 0.05). Further, HSP90, ZFP34, IFNRF4, BCL62, NADHD, TUBB3 and Histone H1 were in greater abundance in sperm of high- compared with low-fertility bulls. The two key biological processes of proteins differentially expressed in high- and low-fertility bulls were metabolic processes and biological regulation. The most prominent molecular functions for proteins that differed are binding, catalytic and receptor activities. The main cellular components for proteins that differed are cellular, extracellular, and plasma membrane. Since protein content differed in high- versus low-fertility bulls, we inferred that the efficiency of associated sperm functions that are necessary for fertility may also differ between high- and low-fertility semen. In conclusion, differences between high- and low-fertility bulls regarding abundance of sperm and seminal plasma proteins likely contributed to differences in fertility.

Seasonal and age-related changes in semen characteristics and composition of seminal plasma in sex-reverse female rainbow trout (Oncorhynchus mykiss) in comparison with normal males

All-male or all-female progeny is preferable in reproduction of fish species. In rainbow trout, all-female progeny is desirable, and the most common and healthful approach is to use sex reversed (SR) females as broodstock by including androgen hormones through the diet at the larval stage. The purpose of this study was to determine the differences and changes of seminal plasma ions (Na+, K+, Ca2+, Mg2+ and Cl−) and pH in 2 to 3 and 3 to 4 year-old SR females, compared with 2 to 3 year-old normal (N) males at the beginning, middle, and end of the spawning season (SS). Additionally, osmolality, spermatozoa concentration, and sperm motility characteristics were determined. Percentages of sperm motility of SR females were negatively correlated with seminal plasma pH and sperm concentrations (r = −0.479 and r = −0.534, respectively, P < 0.05). Seminal plasma pH (7.14 ± 0.05 to 7.40 ± 0.10) in SR females was less than for N males (7.66 ± 0.10 to 8.04 ± 0.10) at all periods of the SS (P < 0.05). The Ca2+ concentrations in the mid-SS were 0.74 ± 0.23 mM in N males, 1.09 ± 0.29 mM in 2 to 3 year-old SR females, and 0.83 ± 0.29 in 2 to 3 year-old SR females, without significant differences (P > 0.05). Furthermore, using of 2 to 3 year-old rather than 3 to 4 year-old SR females for reproduction could provide an advantage in terms of sperm motility characteristics. These findings could be useful for not only understanding of SR of semen from sexually reversed females but also for design of a maturation medium both for further studies and aquaculture production.

Effect of carp pituitary homogenate (CPH) and sGnRHa (Ovaprim) on northern pike (Esox lucius) spermiation stimulation and its effect on quantity and quality of sperm

The effect of carp pituitary homogenate (CPH, n = 7) at a dose of 2.0 mg kg−1 and (D-Arg6, Pro9NET)-sGnRH + domperidone (Ovaprim, n = 7) at a dose of 0.5 ml kg−1 in northern pike (Esox lucius) sperm maturation under controlled conditions was examined. On the control group, 0.9% NaCl at a dose of 1.0 ml kg−1 (n = 7) was used. Sperm was collected 48 h following injection. Sperm quantity (total sperm volume, total sperm production and sperm concentration), sperm motility using the Computer-assisted sperm analysis (CASA) system and sperm and seminal plasma quality (sperm pH, seminal plasma osmotic pressure and seminal plasma pH) were determined for each male separately in each group. The results of the present study demonstrate that hormonal treatment had a positive effect on sperm maturation in northern pike, regardless of the hormonal preparation used. However, even though no differences were found in total sperm volume and total sperm production between fish injected with either CPH or Ovaprim, it should be highlighted that the highest progressive motile sperm (PRG), straight-linear velocity (VSL) and movement linearity (LIN) was noted in fish treated with Ovaprim. It was also found that it is possible to collect sperm from non-hormonally manipulated fish. However, in such a case, only a small sperm volume (around 0.1 ml) characterised by lowered PRG (below 40%) was noted. Considering the fact that only after Ovaprim application sperm motility with progressive movement of sperm above 50% was observed, the hatchery practice of collection of sperm 48 h after its application (at a dose of 0.5 ml kg−1) may be recommended.

The Role of Oxidative Stress, Selected Metals, and Parameters of the Immune System in Male Fertility.

The aim of the study was to investigate the associations between standard semen parameters and the parameters reflecting oxidative stress intensity, antioxidant defense functions, levels of selected macro and trace elements, and parameters characterizing immune system function. The study group consisted of 103 fertile males. Based on semen volume, sperm concentration, total sperm count, and percentage of motile sperm at 1 hour postcollection, the individuals were divided into two equal groups—those with excellent (EX) semen quality and those with mediocre (ME) semen quality. The remaining measured parameters characterizing motility and the percentage of normal morphology were higher in the EX group than in the ME group; however, the seminal plasma pH did not differ between the examined groups. The phosphate level was 31% lower in the EX group than in the ME group, whereas there was a tendency toward a 25% lower level of Fe in the EX group than in the ME group (p = 0.064). The activities of enzymes involved in antioxidant defense, CuZn-SOD, CAT, and G6PD, were 14%, 63%, and 39%, respectively, higher in the EX group than in the ME group. However, the level of alpha-tocopherol was 32% lower in the EX group than in the ME group. The other measured parameters characterizing antioxidant defense and the parameters of oxidative stress intensity and immune system function were not significantly different. The value of seminal plasma pH is not related to the semen quality of fertile males. Higher fertility potential estimated based on standard semen parameters in fertile males is associated with lower levels of Fe and higher activities of some antioxidant enzymes.

Multiple collections of common carp Cyprinus carpio L. semen during the reproductive period and its effects on sperm quality

Multiple collections of semen during the reproductive period of the common carp Cyprinus carpio L. were used to analyse changes in semen quality. Semen collection was performed on June 1 (first collection), 12 (second collection), and 19 (third collection) from individual males (n=11) by gentle abdominal massage. Semen quantity (semen volume and sperm count), quality (sperm motility and sperm viability), as well as seminal plasma parameters (pH of seminal plasma and seminal plasma osmotic pressure) and its enzymatic activity, e.g., lactate dehydrogenase (LDH) and ß-N-acetylglucosaminidase (ß-NAG) were determined. Moreover, for the first time, the percentage of live, dead, and apoptotic sperm, as well as the proteolytic activity of seminal plasma, were determined using flow cytometry and zymography, respectively, at specific times during the common carp reproductive period. The lowest volumes of semen and sperm concentration were noted during the first semen collection (June 1). Analysis of computer-assisted sperm analysis parameters revealed the greatest sperm motility, sperm velocity, as well as amplitude of lateral head displacement, were evident in the third collection (June 19). There were no differences in progressively motile sperm, movement linearity, wobbling index, and beat cross frequency between the different collection times. The lowest percentage of live sperm was found in the first collection, although with the passage of time values of this parameter increased. Seminal plasma pH and seminal plasma osmotic pressure were at the lowest values in the second collection (June 12), which corresponded with the lowest concentration of sperm. In the first collection, seminal plasma contained the highest values of LDH and ß-NAG activity, whereas there were no differences in the proteolytic activity of seminal plasma determined between the different collections of semen. The results presented here indicate that during the reproductive period, males of common carp produce a large amount of semen of moderate quality. Low sperm motility noted in the second collection might be explained by a significant increase in sperm production during this period, followed by a low seminal plasma pH and high hydration rate. The high LDH and ß-NAG activity noted in the first collection of semen may reflect a reduced stability of the sperm cell membrane and its viability. The significant difference in the percentage of live sperm at June 1 compared to that at June 19 supports this hypothesis.

Seasonal Changes in the Milt Quality of Waigieu Seaperch, Psammoperca waigiensis: Implications for Artificial Propagation

AbstractMilt quality of Waigieu seaperch was sampled at the beginning, the middle, and the end of the spawning season to assess if the sampling season has an effect on milt quality parameters. The milt volume and total sperm production were higher at the middle of the spawning season while the sperm concentration in milt was significantly higher at the beginning and the end of the spawning season. Sperm morphology and the major parameters of seminal plasma (pH, total protein, Mg2+, or Ca2+ concentrations) did not differ throughout the spawning season. The concentrations of Na+ and the osmolality increased throughout the spawning season. The percentage of motile cells did not differ during the spawning season while the duration of sperm motility (swimming duration) and velocity (swimming speed) were significantly different during the spawning season. The fertilization rate (75.7 ± 6.8%) and hatching rate (56.5 ± 3.1%) at the middle of the spawning season were higher than at the beginning and end periods. Results indicated that milt quality parameters and fertility success in the middle of the spawning season were higher compared to earlier and later sampling dates. Thus, we recommend collecting milt during this time for maximal fertilization and hatching success.