The Use of Animal\u2019s Body, Scrotal Temperature and Motion Monitoring in Evaluating Boar Semen Production Capacity

Nurture vs nature: how can we optimize sperm quality?

Relationship between semen parameters and mercury concentrations in blood and in seminal fluid from subfertile males in Hong Kong

Impact of age, clinical conditions, and lifestyle on routine semen parameters and sperm kinematics

In temperate regions, boars experience environmental heat stress due to the subtropical climate, leading to their semen quality and fertility being severely compromised compared to indigenous breeds. Considering the above effect, the present study aimed to evaluate the effect of season on semen quality, seminal plasma antioxidant status, and in vivo fertility of crossbred boars of exotic (50%) and indigenous inheritance in a subtropical climate. A total of 14 Hampshire-Ghungroo crossbred boars were used for this investigation, which took place in both summer and winter. Sperm characteristics, namely motility, viability, abnormality, acrosomal integrity, and the hypo-osmotic swelling test (HOST) results, and mitochondrial membrane potential (MMP) were evaluated. Sperm kinematics parameters were assessed using computer-assisted semen analysis (CASA). Antioxidant biomarkers (glutathione peroxidase, GPx; catalase, CAT; and total antioxidant capacity, TAC) and lipid peroxidation (malondialdehyde, MDA) were analyzed in boars' seminal plasma. The summer season had a significant (p < 0.01) negative impact on reaction time and false mounts, whereas semen volume and sperm concentration were significantly (p < 0.01) higher in the winter season. Similarly, sperm abnormalities were significantly (p < 0.01) lower in the winter season. In the winter, sperm quality parameters, namely total motility, progressive motility, viability, acrosomal integrity, and HOST reactivity, were significantly (p < 0.01) improved. However, during the summer, sperm MMP was significantly (p < 0.01) lower in fresh samples and after 72 h of storage. Season had a significant (p < 0.05) effect on the following sperm kinematics parameters: average path velocity, straight-line velocity, curve linear velocity, amplitude of lateral head displacement, and beat cross frequency. Semen characteristics were significantly (p < 0.01) improved in winter after 72 h of cold storage compared with those in summer. The summer season had a significant effect (p < 0.01) on seminal plasma antioxidant biomarkers (TAC, MDA, CAT, and GPx). Furthermore, the farrowing rate was significantly (p < 0.05) higher in the winter season. In conclusion, our results showed that the low MMP of boar sperm and the downregulation of seminal plasma antioxidant biomarkers in summer lead to poor semen quality and poor fertility in Hampshire-Ghungroo crossbred boars in a subtropical climate. To alleviate the heat-stress-induced poor sperm fertility in boars and to optimize the fertility of boars during summer in subtropics, there is a need for scientific interventions in terms of genetics [less exotic inheritance (below 50%)], nutrition, and management.

African medicinal plant like soursop (Annona muricate L.) within annonaceae are known for their biological, therapeutic, and pharmacological properties with little or no toxicity. The use of such plant requires good knowledge of the toxicity dosage, purity, suitable extraction solvent and adverse effects. The leaves, seeds, fruits, barks, and roots of African medicinal plants have been used for various nutraceuticals and functional effects according to African folk medicine. The aim of this study is to evaluate the semen quality, oxidative activity and spermatozoa kinematics of rooster semen in soursop juice extender. About 30 roosters were used for the in vitro analysis. Semen was collected twice a week for 2 weeks through dorsal-abdominal massage technique. The evaluation was done hourly until semen quality declined at the 5th-hour. The pooled semen was allotted to seven treatments of semen extenders as undiluted semen, dextrose saline, 10% soursop juice extender, 20% soursop juice extender, 30% soursop juice extender, 40% soursop juice extender, and 50% soursop juice extender for the study. The percentage motility, progressive motility, nonprogressive motility, curvilinear velocity, average path velocity, straight line velocity, linearity, straightness, amplitude of lateral head, beat cross frequency and wobble were analyzed using computer aided sperm analysis. Oxidative status (antioxidant activity and lipid peroxidation) was determined by assay. Result of rooster semen at room temperature and after 1-hour dilution showed that percentage motility, nonprogressive motility, and average path velocity were significantly (P < 0.05) reduced by different soursop juice extenders compared to undiluted semen. After 2-hour dilution of rooster semen, nonprogressive motility, average path velocity, curvilinear velocity, straight line velocity, wobble, liveability and amplitude of lateral head parameters were significantly (P < 0.05) increased by different soursop juice extenders compared to undiluted semen. Antioxidant activity and lipid peroxidation in both room temperature and after 5-hour dilution were affected by different soursop juice extenders in rooster semen. In conclusion, supplementation of soursop juices as an extender to rooster undiluted semen played an improvement role on spermatozoa fertility and oxidative status during processing or preserving ejaculates for insemination.

This study aimed to test the motility parameters of frozen semen from Pesisir bulls with and without sexing. The research material consisted of semen from two Pesisir bulls. The data obtained were statistically analyzed using ANOVA. The results of this study showed that the motility percentage of Pesisir bulls ranged from 53.66 to 58.87%, and progressive motility ranged from 41.20 to 48.87%. The values of distance curve line (DCL) ranged from 24.05 to 28.24m, distance average path (DAP) ranged from 24.05 to 24.35m, and distance straight-line (DSL) ranged from 18.49 to 22.78m. The values of velocity curve line (VCL) ranged from 93.95 to 112.97m/s, velocity average path (VAP) ranged from 53.90 to 62.57m/s, and velocity straight-line (VSL) ranged from 41.97 to 50.51m/s. The values of linearity (LIN) ranged from 0.43 to 0.45, straightness (STR) ranged from 0.75 to 0.80, and wobble (WOB) ranged from 0.54 to 0.59. Meanwhile, the amplitude of lateral head (ALH) value was between 4.22 and 5.14m, and the beat cross frequency (BCF) value ranged from 21.34 to 26.99Hz. The motility parameters, progressive motility, DAP, DSL, VAP, VSL, and LIN of post-thawing Pesisir bulls semen did not show significant differences (P>0.05) both with and without sexing. However, there were significant differences (P<0.05) in the parameters of progressive motility, DCL, VCL, STR, WOB, ALH, and BCF. However, for future research, it is expected that studies could involve more significant and more diverse sample sizes, as well as variations in cryopreservation techniques that may be employed. Additionally, further research could consider factors such as the age and health condition of Pesisir bulls, which could influence semen quality after thawing.

The objective of this study was to assess the quality of semen produced by two breeds of bucks, namely, Malya and Boer. A total of 90 ejaculates, 45 from each of six bucks comprising two breeds, Boer and Malya, were longitudinally collected for six months via artificial vaginas. Ejaculate collections were assessed for multiple parameters to assess semen quality and reproductive potential as related to performance. The assessment is based on a comparison of average scores between Boer and Malya bucks. These assessments incorporate variables such as the volume of ejaculate, the sperm concentration, and normal morphology, viability, and acrosome integrity. Furthermore, the integrity of sperm membranes and various velocity kinematics, such as straight-line velocity, average path velocity, and curvilinear velocity, and parameters such as lateral head amplitude, beat cross frequency, straightness and linearity metrics, were included. The findings revealed breed-specific differences in semen quality, providing significant detail for reproductive management techniques. Comparatively, Malya bucks were significantly (p&lt;0.05) superior to Boer bucks in terms of volume, viability, normalcy, and kinetics, such as curvilinear velocity, beat cross frequency, straightness, linearity and velocity average pathway, whereas Boer bucks were statistically better in terms of straight-line velocity and beat cross frequency. No significant (p&gt;0.5) breed differences were found in concentration, progressive motility, or membrane or acrosomal integrity. Compared with Boer bucks, Malya bucks presented outstanding semen quality values and are likely well adapted to the environment, making them more ideal for artificial insemination.

Impact of diurnal scrotal temperature on semen quality

Scrotal temperature and semen quality have been found to be inversely correlated in several studies, and variation in scrotal temperature may contribute to the well known variation in semen quality. The reason for the variation in scrotal temperature is not well understood although determinants could be of a genetic nature. We monitored scrotal skin temperature for 24 h in a group of monozygotic and dizygotic twins and single-born brothers (n = 48 males). A thermistor was attached to the underwear and the temperature of the scrotal skin was recorded every 5 min using a small portable data logger. A correlation in median scrotal temperature was found among monozygotic twins (r = 0.64, P = 0.01), but not in dizygotic twins and single-born brothers (r = 0.17, NS). Similar results were found for other percentiles of temperature. The results suggest a genetic component to the variation in scrotal temperature. An hereditary element in male fecundity may be expressed through scrotal temperature, which constitutes a mechanism independent of those responsible for the development of the sperm producing epithelium.

Research Note: Evaluation of two methods for adding cryoprotectant to semen and effects of bovine serum albumin on quality characteristics of cryopreserved rooster spermatozoa

IntroductionMale reproductive health is rapidly declining during the past decades and it is well known that scrotal temperature is linked to male infertility.Material and methodsWe performed a prospective data evaluation within a counterfactual analysis study design. Scrotal cooling was performed using Snowballs™ underwear, scrotal temperature was monitored using a wireless temperature sensor (SensorPush, Brooklyn, NY, 11215)ResultsOverall, scrotal skin temperatures were monitored for 1008 hours. Median scrotal skin temperature was 34.6°C (IQR 33.1 to 35.3) and 35.3°C (IQR 34.4 to 35.9) in the experimental (SnowWedge™) period and control period, respectively, which was significantly different (P <0.001).ConclusionsCyclic scrotal skin cooling using specialized underwear is feasible and efficacious without impairing the activities of daily living and reduces median scrotal skin temperature significantly by 0.7°C. Given the proven association of scrotal skin temperature and semen quality, cyclic scrotal skin cooling by a device such as Snowballs™ underwear may eventually increase semen quality and fertility.

Sperm quality is often evaluated through computer-assisted semen analysis (CASA) and is an indicator of boar fertility. The aim of this research was to study the relationship between CASA motility parameters and fertility results in pigs. Insemination records and semen parameters from a total of 45,532 ejaculates collected over a 3-yr period were used. The statistical model for analysis of fertility data from these inseminations included factors related to sow productivity. The boar- and semen-related variance (direct boar effect) were corrected for the effects of individual boar, genetic line of the boar, age of the boar, days between ejaculations, number of sperm cells in an ejaculate, number of sperm cells in an insemination dose, and AI station. The remaining variance was analyzed if semen motility parameters had a significant effect. This analysis revealed significant (P < 0.05) effects of progressive motility, velocity curvilinear, and beat cross frequency on farrowing rate (FR). Total motility, velocity average path, velocity straight line, and amplitude of lateral head displacement affected (P < 0.05) total number of piglets born (TNB). Boar- and semen-related parameters explained 5.3% of the variation in FR and 5.9% of the variation in TNB. Motility parameters, measured by CASA, explained 9% of the boar- and semen-related variation in FR and 10% of the boar- and semen-related variation in TNB. Individual boar and genetic line of the boar affected (P < 0.0001) the variation in FR and TNB. No differences (P > 0.05) were observed between effects of AI stations on fertility outcome, underscoring the objectivity of the CASA system used. Motility parameters can be measured with CASA to assess sperm motility in an objective manner. On the basis of the motility pattern, CASA enables one to discriminate between the fertilizing capacity of ejaculates, although this depends on the genetic line of the boar used in AI stations.

In the subtropics, bucks show seasonal breeding patterns, and their semen quality decreases during the non-breeding season. Therefore, breeders tend to improve bucks’ semen quality before the breeding season for higher conception rates. In the current study, we hypothesised that simultaneous administration of equine chorionic gonadotrophin (ECG) and melatonin would improve fresh semen quality in bucks before the breeding season. Nine Beetal bucks were randomly assigned (n=3 per treatment) to three treatments: control, melatonin, and melatonin + ECG. Melatonin implants (18 mg; BTC Lab) were placed subcutaneously at the base of the ear. Bucks in the melatonin + ECG treatment were administered ECG (400 IU; Syncro-Part, Ceva Santé Animale) intramuscularly on every fourth day until the end of the experiment. Control bucks were administered normal saline (400 IU; Otuska Pakistan) intramuscularly on every fourth day. Semen was collected twice per week using an artificial vagina (42°C) and immediately evaluated for volume, color, pH, and contaminants. Sperm concentration, motility and kinematics (curvilinear velocity, straight-line velocity, average path velocity, and amplitude of lateral head displacement), viability, DNA, and acrosomal and mitochondrial integrity were monitored using a computer-assisted semen analyzer (AndroVision, Minitube). Weekly concentrations of plasma testosterone and melatonin of all bucks were analysed using radioimmunoassay (Immunotech, Beckman Coulter Ltd.) and enzyme-linked immunosorbent assay (450nm), respectively. Comparisons within and between treatments were made using generalised linear models (repeated-measures analysis of variance). Weekly single-point variance between the treatments was determined (analysis of variance) at P ≤ 0.05 (SPSS ver. 20.0; IBM Corp.). Semen quality (volume, pH, total motility (%), and concentration) improved after Week 4 in the melatonin + ECG treatment compared with the control and melatonin treatments (P&amp;lt;0.05). Similarly, progressive motility (%), viability, DNA, acrosomal and mitochondrial integrity, and sperm kinematics (curvilinear velocity, straight-line velocity, average path velocity, and amplitude of lateral head displacement) improved (P&amp;lt;0.05) after Week 4 in the melatonin + ECG treatment. Similarly, non-viability and ratio of abnormal spermatozoa decreased by Week 3 in the melatonin + ECG treatment (P&amp;lt;0.05) compared with the control and melatonin treatments. Likewise, plasma testosterone concentration (ngmL−1) of bucks was higher (P&amp;lt;0.05) at Week 3 in the melatonin + ECG treatment (4.2±0.2) than in the melatonin (0.8±0.1) and control (1.2±0.1) treatments. Within the melatonin + ECG treatment, plasma testosterone concentration was higher (P&amp;lt;0.05) at Week 5 (4.9±0.2) and Week 9 (4.5±0.1) than at Week 3 (4.2±0.2). Plasma melatonin concentration (pgmL−1) increased (P&amp;lt;0.05) from Week 5 onward in the melatonin + eCG (12.5±0.1) and melatonin (10.2±0.1) treatments compared with the control (2.65±0.1). In conclusion, the simultaneous administration of melatonin and ECG improved fresh semen quality in Beetal bucks.

The latest entry in the field of semen evaluation is computer assisted semen analysis (CASA). Heterospermic insemination has been used to increase pregnancy rates from low fertile bulls. The objective of this study was to evaluate, with the aid of CASA, heterospermic semen characteristics and pregnancy rates using different concentrations of bull semen in a timed artificial insemination protocol. Semen was collected from two bulls of known fertility by artificial vagina and all CASA motility parameters were evaluated individually and combined. Straws were filled using a semi-defined semen extender (Andromed, Minitüb, Tiefenbach, Germany) as follows: single bull A and single bull B (12 × 106 of progressive motile cells after thawing); Mixed bull semen: A + B (12 × 106 of progressive motile cells after thawing) and Supermix bull semen: A + B (28 × 106 of progressive motile cells after thawing). All cows received a P4 intravaginal device (DIB, Syntex, Argentina) and 2 mg of EB i.m. (Syntex) on Day 0, 500 mg cloprostenol (Estroplan, Syntex) at the time of DIB removal (Day 8), and 1 mg EB i.m. on Day 9. Fixed-time insemination (FTAI) was performed at 52 to 56 h after DIB removal. A total of 249 cows were randomly allocated to be inseminated with bulls A and B (n = 76), with Mixed A + B (n = 87), and with Supermixed A+B at a high concentration (n = 86) by a single inseminator. Pregnancy rates were evaluated at 38 days after insemination by transrectal ultrasonography. Means and standard deviations or each characteristic were calculated, compared, and statistically analyzed. The following sperm motility parameters were determined with the Ceros 12.1 sperm analyzer (Hamilton Thorne Biosciences, Inc., Beverly, MA, USA) on at least 1000 spermatozoa: velocity average path (VAP), velocity straight line (VSL), curvilinear velocity (VCL), amplitude lateral head (ALH), beat cross frequency (BCF), straightness (STR), linearity (LIN), and percentage of rapid or static cells. There were no significant differences (P &gt; 0.05) in VAP, VSL, VCL, ALH, STR, or LIN. There was a numerically higher percentage of rapid cells in the Supermix semen. Pregnancy rate from bulls A and B was 61% and from Mixed A + B 60%, while that from Supermixed A + B was 69%. Results from the analysis indicate that semen concentration is an important element to be considered in a timed artificial insemination program. Numerically higher pregnancy rates were obtained with double semen concentration in the straw. More research is required to evaluate the interaction between different breeds within a timed artificial insemination program. This research was supported by Centro Genético Bovino de EOLIA sa and Syntex sa Argentina.

Oxidative stress has been identified as a major cause of low seminal fertility. Among the components of stallion seminal plasma, some enzymatic and non-enzymatic antioxidants have been identified, which protect sperm from injurious effects of reactive oxygen species (ROS); however, the characterisation of these components is still in preliminary stages, as well as their relationship with freezability. The aim of this study was to evaluate the effect of some components of seminal plasma (SP) on stallion semen freezability. Semen of 30 Colombian Creole horses, and a total of 60 ejaculates, were collected. Semen was centrifuged to recover the SP. It was lyophilized and some components were assayed: total protein concentration (TP) by Bradford assay, CRISP3 protein concentration by ELISA, vitamin C (CVIT), vitamin E (EVIT) and vitamin A (AVIT), by HPLC; content of iron (Fe), copper (Cu), magnesium (Mg) and Zinc (Zn) by atomic absorption spectroscopy flame. Semen was supplemented with 10% stallion lyophilized SP and cryopreservation was performed. Post-thaw, total motility (TM), progressive motility (PM), straight line velocity (VSL), curvilinear velocity (VCL), average path velocity (VAP), amplitude of lateral head displacement (ALH) and beat cross frequency (BCF), were assessed using a computer-assisted sperm analysis (SCA®, Microptic SL, Barcelona, Spain). Sperm viability (SV) was determined by the Live/Dead kit (Molecular Probes Inc., Eugene, OR, USA). Normal sperm morphology (NM) was performed by the supravital technique and plasmatic membrane integrity (MI) was evaluated by the hypo-osmotic test. For statistical analysis, completely randomised mixed models were fitted. Levels according to the concentration of components of SP (high, medium, and low) were established. Comparisons of the means between levels were done with Tukey’s test. The significance level used for all assessments was P &lt; 0.05. Means for TP of 0.35 mg BSA/g, CRISP3 of 55.22 ng/mg, CVIT of 2.66 mg/g, EVIT of 72.36 µg/g, AVIT of 37.37 µg/g, Fe of 17.37 mg/kg, Cu of 33.64 mg/kg, Mg of 109.08 mg/kg, and Zn of 0.49 g/100 g of SP were found. We found that a high level of CRISP3, AVIT, Cu, and Fe had higher results for post-thaw TM, PM, NM; medium levels of TP and Mg showed higher post-thaw TM, PM, NM, and MI; and lower levels of Zn had better results for post-thaw TM, PM, VCL, and VAP. In contrast, high and medium levels of CVIT had a deleterious effect on post-thaw TM, PM, SV, NM, and MI. We concluded that there is a relationship between concentrations of seminal plasma components and stallion semen freezability.