Concentration of copper, iron, zinc, cadmium, lead, and nickel in boar semen and relation to the spermatozoa quality

Iodine Supplementation Improved Antioxidant Status, Hormonal Status, Sexual Behavior, and Semen Production Performance of Bos indicus Bulls Under Tropical Climatic Condition

Iodine is anessential micronutrient that plays a crucial role in male reproduction (sexual behavior and semen production performance) by modulating thyroid function and the antioxidant status of the animal. Nonetheless, in Bos indicus bulls, a thorough evaluation of the effects of dietary iodine supplementation on antioxidant status, seminal quality parameters, and its interaction with other minerals is not documented. Twelve Bos indicus (Sahiwal) bulls were distributed into three groups (n = 4 in each group) viz. T₁ (control), T₂, and T₃ and fed diets containing 0.250, 0.375, and 0.500 ppm iodine/ kg dry matter intake, corresponding to 0%, 50%, and 100% higher than ICAR (2013) recommendations, respectively. The experimental feeding was carried out for 60 days and the effects on nutrient utilization, hormonal and antioxidant status, and sperm function tests were investigated. Results revealed that body weight, dry matter intake, and nutrient digestibility remained unaffected by dietary supplementation of iodine. Testosterone and thyroxine hormone concentrations were improved (p<0.05) in T₂ and T₃ groups. Blood and seminal iodine content were also higher (p<0.05) in both the supplemented groups (T₂ and T₃). Sperm functions viz. viability, physical membrane integrity, acrosomal integrity, motility, and mitochondrial membrane potential were improved (p<0.05) due to iodine supplementation. Furthermore, lipid peroxidation and membrane scrambling in spermatozoa were reduced (p<0.05) in T₂ and T₃ groups. Blood antioxidant status (total antioxidant activity and GPx levels) was improved (p<0.05) in T₂ and T₃. Sexual behavior was also improved (p<0.05) in iodine-supplemented groups. Hence, it can be concluded that iodine supplementation at the dose rate of 0.500 ppm in the Bos indicus bull diet is beneficial in improving hormonal status, antioxidant status, and semen quality.

Exogenous Factors Affecting the Functional Integrity of Male Reproduction

Natural processes along with increased industrial production and the irresponsible behavior of mankind have resulted in environmental pollution. Environmental pollutants can be categorized based on their characteristics and appearance into the following groups: physical, biological, and chemical. Every single one of them represents a serious threat to the male reproductive tract despite the different modes of action. Male gonads and gametes are especially vulnerable to the effect of exogenous factors; therefore, they are considered a reliable indicator of environmental pollution. The impact of xenobiotics or radiation leads to an irreversible impairment of fertility displayed by histological changes, modulated androgen production, or compromised spermatozoa (or germ cells) quality. The present article reviews the exogenous threats, male reproductive system, the mode of action, and overall impact on the reproductive health of humans and animals.

Effects of Cadmium, Lead, and Mercury on the Structure and Function of Reproductive Organs

Reproductive organs are essential not only for the life of an individual but also for the survival and development of the species. The response of reproductive organs to toxic substances differs from that of other target organs, and they may serve as an ideal “barometer” for the deleterious effects of environmental pollution on animal and human health. The incidence of infertility, cancers, and associated maladies has increased in the last fifty years or more, while various anthropogenic activities have released into the environment numerous toxic substances, including cadmium, lead, and mercury. Data from epidemiological studies suggested that environmental exposure to cadmium, lead, and mercury may have produced reproductive and developmental toxicity. The present review focused on experimental studies using rats, mice, avian, and rabbits to demonstrate unambiguously effects of cadmium, lead, or mercury on the structure and function of reproductive organs. In addition, relevant human studies are discussed. The experimental studies reviewed have indicated that the testis and ovary are particularly sensitive to cadmium, lead, and mercury because these organs are distinguished by an intense cellular activity, where vital processes of spermatogenesis, oogenesis, and folliculogenesis occur. In ovaries, manifestation of toxicity induced by cadmium, lead, or mercury included decreased follicular growth, occurrence of follicular atresia, degeneration of the corpus luteum, and alterations in cycle. In testes, toxic effects following exposure to cadmium, lead, or mercury included alterations of seminiferous tubules, testicular stroma, and decrease of spermatozoa count, motility and viability, and aberrant spermatozoa morphology.

Relationship between concentrations of macro and trace elements in serum and follicular, oviductal, and uterine fluids of the dromedary camel (Camelus dromedarius)

This study aimed at investigating the relationship between concentrations of macro and trace elements in blood serum, and fluids from small and large follicles (SFF and LFF, respectively), oviduct (OF), and uterus (UF) of female dromedary camels. Fluids from small (2-6 mm) and large follicles (7-20 mm), oviduct and uterus, and blood samples were collected from 19 camels. The results indicated that the concentrations of serum Mg, Fe, and Mn were significantly higher than their follicular fluid, OF, and UF concentrations. Levels of Zn, Fe, Cu, Cr, and Mn were significantly higher in SFF than in LFF. Se and Mo concentrations were higher in LFF. Co concentration was lower in serum than in reproductive tract fluids. Cr concentration was higher in UF and OF than in the serum, SFF, and LFF. High Ca concentration was observed for serum and SFF, followed by LFF. The concentration of Na was about 1.18-fold higher in SFF than in serum, OF, and LFF, and approximately 4.1-fold higher in serum than in UF. K was present in higher concentration in SFF than in serum and LFF; however, its concentration was low in UF and OF. In conclusion, this study shows the concentrations of certain elements in small and large follicular, uterine, and oviductal fluids, which may be low or high depending on their function in the development and growth of follicles. This information can support the development of new media for in vitro oocyte maturation and fertilization of female camels.

Serum and Seminal Plasma Element Concentrations in Relation to Semen Quality in Duroc Boars

Element concentrations in serum and seminal plasma were studied in Duroc boars with different semen quality characteristics. Based on the utilization rate of 2174 ejaculates from June to August in 2016, a total of 166 Duroc boars were allocated into three groups: low utilization rate group (LG, 0 to 60% utilization rate), medium utilization rate group (MG, 60 to 80%), and high utilization rate group (HG, 80 to 100%). Serum and seminal plasma samples were collected, and element levels were analyzed using inductively coupled plasma mass spectrometry. The results showed that LG boars had higher concentrations of serum copper and seminal plasma cadmium compared with MG and HG boars (P < 0.05), and serum copper and seminal plasma cadmium were negatively correlated with sperm motility, while positively correlated with the abnormal sperm rate. We observed the abnormal sperm rate increased by approximately 4.53% with serum copper increasing from 1.63 to 2.44 mg/L, while sperm motility decreased by approximately 2.85% with seminal plasma cadmium increasing from 0 to 0.82 μg/L. Moreover, serum iron and manganese levels in the LG group were significantly reduced compared with the HG boars (P < 0.05), and the two elements were negatively correlated with the abnormal sperm rate (P < 0.05). In conclusion, excessive copper and absence of iron and manganese in serum as well as higher seminal plasma cadmium may reduce the utilization rate of semen by impairing sperm motility and morphology, indicating the importance of adding and monitoring microelements in boar diet.

Trace elements content in semen and their interactions with sperm quality and RedOx status in freshwater fish Cyprinus carpio: A correlation study

Objective of the present study was to investigate interactions between trace elements content and RedOx status, as well as sperm quality parameters (motility features, DNA fragmentation) in fish spermatozoa in natural conditions. Reproductively mature male freshwater fish (n = 16) of Cyprinus carpio breed were used in the study. Trace elements content was determined in fish milt samples by inductively-coupled plasma optical emission spectrometry (ICP-OES) and by cold-vapor atomic absorption spectroscopy (CV-AAS). Sperm quality evaluation was realized by computer-assisted sperm analysis (CASA) quantifying several parameters: concentration, total motility, progressive motility, distance average path, distance curved line, distance straight line, velocity average path, velocity curved line, velocity straight line, straightness, linearity, amplitude of lateral head displacement and beat cross frequency. The general scheme of descending concentrations of trace metals in semen samples was following: Zn > Fe > Cu > As > Sr > Ni > Mn > Se > Pb > Cr > Cd > Hg. Total motility of spermatozoa was relatively high (91.45%), however progressive motility was not even half of this value (39.47%). Sperm DNA fragmentation values were relatively low (4.00-6.29%). The percentage of immotile spermatozoa showed a significant correlation with all RedOx status parameters and also with DNA fragmentation. Positive statistically significant correlations were observed between trace elements (Mn, Se, Sr, and Zn) and some qualitative spermatozoa parameters (velocity and distance parameters). Cu and Hg content shows similar negative associations with progressive motility. Hg also interacted with production of malondialdehyde. Overall, the present study suggests application of multi-component mixtures of environmentally related trace elements concentrations when assessing the potential reproductive risk.

Zinc ion flux during mammalian sperm capacitation

Sperm capacitation, the ultimate maturation event preparing mammalian spermatozoa for fertilization, was first described in 1951, yet its regulatory mechanisms remain poorly understood. The capacitation process encompasses an influx of bicarbonate and calcium ions, removal of decapacitating factors, changes of pH and sperm proteasomal activities, and the increased protein tyrosine phosphorylation. Here, we document a novel biological phenomenon of a unique zinc (Zn²⁺) ion redistribution associated with mammalian sperm in vitro capacitation (IVC). Using image-based flow cytometry (IBFC), we identified four distinct types of sperm zinc ion distribution patterns (further zinc signature) and their changes during IVC. The zinc signature was altered after sperm capacitation, reduced by proteasomal inhibitors, removed by zinc chelators, and maintained with addition of external ZnCl₂. These findings represent a fundamental shift in the understanding of mammalian fertilization, paving the way for improved semen analysis, in vitro fertilization (IVF), and artificial insemination (AI).

During sperm capacitation physiological changes occur that are required for fertilization. Here, the authors describe four sperm zinc signatures during invitro capacitation that are indicative of sperm quality and capacity to fertilize.

Mineral profiling of ostrich (Struthio camelus) seminal plasma and its relationship with semen traits and collection day

Successful assisted reproduction techniques, with specific focus on in vitro semen storage for artificial insemination, are dependent on certain key elements which includes the biochemical profiling of semen. The objective of this study was to complete an ostrich seminal plasma (SP) evaluation by inductively coupled plasma mass spectrometry (ICP-MS) among seven males at different daily intervals (day 1, 3, 7, 11, 15, 19, 21, 23, 25, 26, 27, 28) for a period of 28 days during spring (August to September) for mineral profiling. The effect of collection day and male on sperm concentration, semen volume and seminal plasma volume, was explored as well as the relationships amongst these specific sperm traits and SP minerals. Variation amongst SP mineral concentrations, accounted for by the fixed effects of sperm concentration, semen volume, seminal plasma volume, collection day and male, ranged from 18% to 77%. Male had the largest effect on variation in SP minerals, namely: phosphorus (P), potassium (K), calcium (Ca), sodium (Na), boron (B), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), molybdenum (Mo), barium (Ba), arsenic (As) and selenium (Se). Sperm concentration instigated fluctuations of P, magnesium (Mg), B, zinc (Zn), Fe, aluminium (Al), Se, manganese (Mn) and lead (Pb). Semen volume had an effect on Na, K, B, Pb and Ba while seminal plasma volume only influenced variation in Na. There were fluctuations among collection days of specific micro minerals, Ni and Mo, with initial Ni concentrations being relatively greater and Mo at lesser concentrations. Semen volume, seminal plasma volume and sperm concentration varied amongst males. Sperm concentrations during the initial collection days, 1 and 3, were less than that for days 7 to 28. Significant variation of SP minerals and sperm characteristics among ejaculates and males suggest an association of these specific elements with sperm function and are, therefore, considered to be of potential importance to success of assisted reproduction technology for the ostrich. The relationship amongst sperm concentration and collection day confirms the need to conduct an initial period of collection to stabilise a greater sperm concentration to optimise sperm numbers for artificial insemination purposes.

Blood concentration of copper, cadmium, zinc and lead in horses and its relation to hematological and biochemical parameters

Environmental pollution results in serious health hazards to animals and blood analysis serves as a good alternative for health status assessment. The target of this study was to analyze the concentration of selected metals in equine blood, to analyze the blood parameters and to find possible correlations. Blood samples were collected from the vena jugularis of healthy adult horses. The highest concentration of all elements was found in whole blood (Cu 3.84 ± 0.90 mg L(-1); Cd = 0.81 ± 0.90 mg L(-1); Zn 26.67 ± 14.12 mg L(-1); Pb 9.33 ± 5.76 mg L(-1)). Higher concentrations of copper, cadmium, zinc and lead were detected in blood clots compared to blood sera (44.04%). A similar tendency was found for cadmium (50%), zinc (13.08%) and lead (46.02%), which showed generally higher concentrations in blood clots (cells). Correlation analysis proved some relations between analyzed elements. In blood clots there is a strong positive correlation between Cd - Pb (r = 0.93) and Zn - Pb (r = 0.71) was detected. For biochemical and hematological parameters mainly medium correlations were detected. Obtained results prove different correlations of analyzed elements in blood components as well as the effect on parameters of blood biochemical and hematological profiles.

Impact of Seminal Chemical Elements on the Oxidative Balance in Bovine Seminal Plasma and Spermatozoa

Mutual relationships between selected chemical elements (Na, K, Fe, Cu, Mg, and Zn), basic motility characteristics (motility and progressive motility), and markers of the oxidative balance (superoxide dismutase, catalase, glutathione, albumin, and malondialdehyde) were investigated in bovine seminal plasma and spermatozoa. Computer assisted sperm analysis was used to assess the motility parameters; mineral concentrations were determined by the voltammetric method and flame absorption spectrophotometry; antioxidants and malondialdehyde were evaluated by UV/VIS spectrophotometry. Concentrations of chemical elements in both seminal fractions were in the following descending order: Na > K > Zn > Mg > Fe > Cu. Higher amounts of all minerals and nonenzymatic antioxidants were detected in the seminal plasma (P < 0.01; P < 0.001), while higher MDA concentration and activity of enzymatic antioxidants were recorded in the cell lysates (P < 0.01; P < 0.001). Na, Fe, Cu, Mg, and Zn were positively correlated with the motility and antioxidant parameters (P < 0.05; P < 0.01; P < 0.001). Inversely, K exhibited the positive associations with malondialdehyde (P < 0.05). This study demonstrates that most chemical elements are integral components of bovine semen and are needed for the protection against oxidative stress development.

Elemental composition of human semen is associated with motility and genomic sperm defects among older men

BACKGROUND

Older men tend to have poorer semen quality and are generally at higher risks for infertility and abnormal reproductive outcomes.

METHODS

We employed proton-induced X-ray emission (PIXE, 3 MeV proton beam) to investigate the concentrations of zinc, copper, calcium, sulfur, chlorine, potassium, titanium, iron and nickel in washed sperm and seminal plasma from non-smoking groups of 10 older men (65-80 years old) and 10 younger men (22-28 years old) who were concurrently assayed for sperm function and genomicly defective sperm.

RESULTS

The older group showed elevated zinc, copper and calcium in sperm and elevated sulfur in seminal plasma compared with the younger men. The older group also showed reduced motility as well as increased sperm DNA fragmentation, achondroplasia mutations, DNA strand breaks and chromosomal aberrations. Sperm calcium and copper were positively associated with sperm DNA fragmentation (P < 0.03). Seminal sulfur was positively associated with sperm DNA fragmentation and chromosomal aberrations (P < 0.04), and negatively associated with sperm motility (P < 0.05). Sperm calcium was negatively associated with sperm motility, independent of male age (P = 0.01).

CONCLUSIONS

We identified major differences in elemental concentrations between sperm and seminal plasma and that higher sperm copper, sulfur and calcium are quantitatively associated with poorer semen quality and increased frequencies of genomic sperm defects.

Dose- and time-dependent effect of copper ions on the viability of bull spermatozoa in different media

The purpose of this in vitro study was to determine the effect of copper (Cu) on the motility and viability of spermatozoa in the presence of different culture media. Specifically, we examined the dose- and time-dependent effect of copper ions (Cu(2+)) on the motility and viability of spermatozoa during different time periods (Time 0 h, 1 h, 24 h). The percentage of motile spermatozoa and progressive motile spermatozoa was determined after exposure to concentrations of 3.9; 7.8; 15.6; 31.2; 62.5; 125; 250; 500; 1000 μM/L of Cu(2+) using the Sperm Vision(TM) CASA (Computer Assisted Semen Analyzer) system. The cell viability was measured by the MTT (metabolic activity) assay. The initial spermatozoa motility in the presence of Cu(2+) in physiological saline solution (PS) showed slight increased values at doses <31.20 μM/L of Cu(2+) compared to the control group. The long-term cultivation (Time 24 h) reduced the average motility values in all experimental groups (P < 0.001) in comparison to the control group. Identical spermatozoa motility was detected for the percentage of progressive motile spermatozoa during all time periods. The culture medium containing 20 % bovine serum albumin (BSA), triladyl and 5 % glucose increased the overall percentage of spermatozoa motility after 1 h of cultivation. A concurrently maintained motility of spermatozoa at doses <62.50 μM/L of Cu(2+) during the long-term in vitro cultivation confirms the protective effect of albumin. The cell viability was decreased significantly (P < 0.001) in all experimental groups with copper administration. The obtained data point out that Cu(2+) at high doses is a toxic element on the spermatozoa motility, which subsequently disrupts the viability of cells. However, using a suitable culture medium containing an energy component- and protein-rich substrate, the spermatozoa motility could increase.

In vitro copper toxicity on rabbit spermatozoa motility, morphology and cell membrane integrity

In this in vitro study the effects of copper sulphate on the motility, morphology and structural integrity of rabbit spermatozoa were investigated. The spermatozoa motility was evaluated by CASA method and Annexin analysis was used for detection of structural changes. For analysis of morphology samples of rabbit semen were fixed with Hancock's solution and stained with Giemsa, and for each sample at least 500 spermatozoa were evaluated. The concentration of copper in the medium varied from 3.57 to 4.85 microg CuSO4/mL. At Time 0 the highest motility was detected in the control group (57.78 +/- 3.90%). Motility in groups with copper administration was lower in comparison to control. Significant differences were detected in groups with 3.70-4.85 microg CuSO4/mL (P<0.05) at Time 0. After 1 h of incubation with copper sulphate the motility significantly decreased almost in all experimental groups. However, at Time 2 h significant increase of total motility was observed in groups with lower concentrations of copper (3.57 and 3.63 microg CuSO4/mL). After 24 and 48 h of incubation almost all the spermatozoa were dead recording no motility at all concentrations. The concentration- dependent decrease of spermatozoa motility up to 50% of control was detected for the group receiving highest copper administration (4.85 microg CuSO4/mL) at Times 1 and 2 h. Progressive motility had an identical trend to that of motility in all experimental groups, at all culture times and for all concentrations. Evaluation of distance and velocity parameters indicated that a sort of stress tolerance developed in lower concentrations (3.57 and 3.63 microg CuSO4/mL). At lower concentrations, an increase was noted for distance parameter DCL and velocity parameter VCL, indirectly confirming the significant motility and progressive motility increase. Other motility parameters (straightness index, linearity index, wobble and amplitude of lateral head displacement) revealed decrease in the group with the highest copper concentration (4.85 microg CuSO4/mL) in comparison to the control group after 2 h of incubation, only. No significant alteration was noted for these parameters in comparison to control at Times 0 and 1 h. The total percentage of morphologically abnormal spermatozoa was significantly higher (P<0.05) in the group with the highest copper concentration (46.20+/-5.54%) in comparison to control (30.60+/-2.91). Predominant morphological abnormalities were acrosomal changes, knob-twisted flagellum and small heads. Detection of spermatozoa with disordered membrane was carried out for groups with higher copper concentrations and control, using Annexin analysis. Analysis showed higher occurrence of positive spermatozoa in the copper-exposed groups. Some Annexin positive reactions from all spermatozoa were detected in the control group. In copper-exposed groups positive reaction proved alteration in anterior part of head (acrosome) and in connection segment (mid-piece) of spermatozoa. Detected data evidently confirm adverse effects of high copper sulphate concentrations in rabbit semen on parameters of spermatozoa motility, morphology and membrane integrity. This paper also indicates the lowest possible toxic concentration of copper (3.70 microg CuSO4/mL) to rabbit spermatozoa in relation to motility.

Cadmium, zinc, copper, sodium and potassium concentrations in rooster and turkey semen and their correlation

The purpose of this study was to assess concentration of selected elements (cadmium, zinc, copper, sodium and potassium) in rooster and turkey semen and to find possible correlations between these elements. Samples were analyzed on the atomic absorption spectrophotometer. The analysis of cadmium showed that the concentration in rooster is 9.06 +/- 7.70 and in turkey 4.10 +/- 3.59 microg/mL. In zinc 5.25 +/- 1.96 microg/mL in rooster and 3.70 +/- 1.26 microg/mL in turkey were detected. Higher concentration of copper was found in rooster semen (6.79 +/- 6.42 microg/mL) in comparison with turkey semen (4.29 +/- 5.43 microg/mL). The level of sodium (3.96 +/- 1.02 microg/mL; 3.14 +/- 0.85 microg/mL) and potassium (2.88 +/- 0.65 microg/mL; 3.42 +/- 1.41 microg/mL) was very similar in both species. Correlation analysis detected high positive correlation between cadmium and zinc (r = 0.701) in rooster and between sodium and potassium (r = 0.899) in turkey semen.

Nickel Seminal Concentrations in Various Animals and Correlation to Spermatozoa Quality

In this study, the concentration of nickel in stallion, bull, ram, boar and fox semen, and its relation with spermatozoa quality was analyzed. The concentration of nickel in semen was 0.20 mg kg(-1) in stallion, 0.12 mg kg(-1) in bull, 0.31 mg kg(-1) in ram, 0.06 mg kg(-1) in boar and 0.36 mg kg(-1) in fox. Seminal nickel concentration was significantly higher (P < 0.05) in foxes than that in bulls and significantly higher (P < 0.01) in rams and foxes in comparison with boars. Evaluation of total pathological spermatozoa revealed the highest number in stallions followed by rams, bulls, boars and foxes. In bull, ram and boar semen, separated flagellum, flagellum torso and knob-twisted flagellum were predominant. Knob-twisted flagellum, separated flagellum and flagellum torso were found in increased number in stallion semen and broken flagellum in fox semen. Correlation analysis in bulls indicated a high positive correlation between seminal nickel and separated flagellum (r = 0.76) and medium positive correlation between nickel and flagellum torso (r = 0.62), and in rams a high positive correlation between nickel and separated flagellum (r = 0.77). Medium positive correlation was found between nickel and separated flagellum (r = 0.43) and between nickel and other pathological spermatozoa (r = 0.45) in boars.

Lead-induced alterations in rat kidneys and testes in vivo

The purpose of this study was to assess the effects of lead administration on the kidney and testicular structure of adult rats. Rats received lead (PbNO(3)) in single intraperitoneal dose 50 mg/kg (group A), 25 mg/kg (group B) and 12.5 mg (group C) per kilogram of body weight and were killed 48 h following lead administration. After the preparation of histological samples the results were compared with control. After the lead administration dilated Bowman's capsules and blood vessels in interstitium of kidney with evident hemorrhagic alterations were noted. Quantitative analysis determined increased relative volume of interstitium and tubules. Also, the diameter of renal corpuscules, diameter of glomeruli and diameter of Bowman's capsule were significantly increased, especially in group A, with the highest lead concentration. In testes, dilatation of blood capillaries in interstitium, undulation of basal membrane and occurrence of empty spaces in seminiferous epithelium were detected. An apoptosis assay confirmed increased incidence of apoptosis in the spermatogenetic cells after the lead administration. Also further morphometric analysis showed significant differences in evaluated parameters between control and treated groups. The number of cell nuclei was decreased in lead-treated groups, which is concerned with the occurrence of empty spaces as well as with the higher apoptosis incidence in germinal epithelium. This study reports a negative effect of lead on the structure and function of kidney and testes.

Cobalt-induced alterations in hamster testes in vivo

The purpose of this study was to assess the effects of cobalt on the testicular structure of adult golden hamsters. Hamsters in group A received cobalt (CoCl2) in single intraperitoneal dose 20 mg/kg, in group B 10 mg/kg and in group C 5 mg CoCl2/kg body weight and were killed fourty eight hours after cobalt administration. Afer a preparation of histological samples the results were compared with control. After a cobalt administration dilatation of blood capillaries in interstitium, undulation of basal membrane and occurrence of empty spaces in seminiferous epithelium was detected. Morphometric analysis showed that in all cobalt-treated groups the relative volume of seminiferous epithelium was significantly decreased. In the relative volume of interstitium a significant increase was found between control group and experimental groups. After cobalt administration we have found linear non-significant decrease. Evaluation of diameter seminiferous tubules found increase of this parameter in the all experimental group in comparison with control. Height of seminiferous epithelium was relatively constant and in all groups but the difference between control and group A was significant (P < 0.05). Analysis of the lumen diameter of seminiferous tubules detected significantly increase mainly group B. Evaluation of the number of cell nuclei per a constant area detected an increase of this parameter in experimental group. Results of this study report a negative effect of cobalt on structure and function of testes.

Seminal concentration of trace elements in fox and relationships to spermatozoa quality

Concentrations of copper, zinc, iron, cadmium, lead, and nickel in the semen of foxes (Vulpes vulpes, n = 10), microscopic analysis of occurrence of pathological spermatozoa, and correlations of these elements with pathological forms were studied. Samples were analyzed by using an atomic absorption spectrophotometer. For analysis of pathological spermatozoa semen samples fixed with Hancock's solution and stained with Giemsa were prepared. For each fox at least 1000 spermatozoa were evaluated. The concentrations of copper, zinc, and iron in semen of foxes were found to be 2.16+/-0.53 mg/kg, 13.09+/-5.22 mg/kg, and 33.16+/-24.36 mg/kg, respectively, on wet weight basis. Concentration of cadmium was low (0.07+/-0.05 mg/kg). The levels of lead and nickel in the semen of foxes were 0.08+/-0.06 mg/kg and 0.35+/-0.24 mg/kg, respectively. The total percentage of pathological spermatozoa was 7.76+/-1.33% with predominancy of knob twisted flagellum, separated flagellum, and broken flagellum. In relation to trace elements the analysis showed significant (p < 0.05) correlation between copper and lead (r = -0.85), copper and other forms of pathological spermatozoa (r = -0.72), zinc and broken flagellum (r = -0.69), iron and retention of cytoplasmic drop (r = 0.87), cadmium and separated flagellum (r = -0.68), and between cadmium retention of cytoplasmic drop (r = 0.87).