Ejaculation effect on blood testosterone and prostatic pulsed-wave Doppler ultrasound in dogs

Impact of autologous platelet-rich plasma used for treatment of oligozoospermia in dogs on the quality of semen and testicular blood flow

Platelet-rich plasma (PRP) is widely used in regenerative medicine, and the current study aimed to investigate the effects of autologous PRP on semen characteristics, testicular blood flow, and testosterone levels in the treatment of oligozoospermia in dogs. Ten stray male dogs diagnosed with oligozoospermia were included in the study. The dogs were randomly assigned to two groups: Group I, the control group (n = 5), which received no treatment, and Group II, the PRP group (n = 5), which received a single intra-testicular injection of 0.5 mL of autologous PRP into each testicle. Testicular hemodynamics, hormonal and biochemical analysis and semen parameters were assessed for both groups and the examination was extended to 8 weeks. The results demonstrated that dogs treated with PRP showed significantly higher values of End Diastolic Velocity (EDV) and Peak Systolic Velocity (PSV) (P < 0.001) at the 6th to 8th weeks post-injection, compared to baseline (day 0) values. Conversely, the values of Resistance Index (RI) and Pulsatility Index (PI) showed a significant decrease (P < 0.001) in group II from week 2 to week 8. Additionally, PRP treatment led to significant increases in sperm concentration, motility percentage, and the proportion of live and normal spermatozoa (P < 0.001), with maximum values observed at 28 and 60 days post-treatment, compared to day 0. Moreover, serum testosterone and nitric oxide (NO) levels were significantly higher (P < 0.001) in group II and remained elevated through the 8th week following injection, compared to baseline values and group I. In conclusion, this study demonstrates that autologous PRP treatment effectively increases sperm concentration, motility, and normal spermatozoa, improves testicular blood flow, and elevates testosterone and NO levels. These findings suggest that PRP may be a promising therapeutic option for the treatment of oligozoospermia in dogs. Further studies are needed to confirm and expand upon these results.

An updated insight on testicular hemodynamics: Environmental, physiological, and technical perspectives in farm and companion animals

In all organs, control of blood flow is important but might be particularly critical for testicular functions. This is because of the very low oxygen concentration and high metabolic rate of the seminiferous tubules, the physiological temperature of the testis, and its location outside the abdominal cavity. Many factors affect the characteristics of TBF in farm and companion animals, such as environment (thermal and seasonal effects) and physiological (species, breeds, age, body weight, and sexual maturity). Thermal environment stress has detrimental effects on spermatogenesis and consequently has more serious impacts on both human and animal fertility. Numerous studies have been performed to assess TBF in different animal species including bulls, rams, bucks, alpacas, stallions, and dogs with varied results. Hence, assessment of TBF by Doppler ultrasonography is of great importance to estimate the effect of high environment temperature on testicular functions. Also, differences observed in the TBF may result from different technical aspects such as the identification of the segment of the testicular artery to be examined. In the current review, we focused on the imperative roles of TBF in various animal species. Besides, we discussed in detail various factors that could affect TBF. These factors can significantly modify the TBF and thus should be considered when establishing reference values in farm animals for better clinical diagnosis. The information provided in this review is valuable for researchers and veterinarians to help them a better understanding of testicular hemodynamics for the proper evaluation of breeding soundness examination in males.

Single melatonin injection enhances the testicular artery hemodynamic, reproductive hormones, and semen parameters in German shepherd dogs

This study aimed to determine the effects of melatonin administration on testicular vascular perfusion in relation to steroid hormones and semen characteristics in dogs. The study included 12 normospermic German shepherd dogs (weighed 35 ± 0.5 kg and aged 4 ± 0.5 years). Males received a single melatonin administration (melatonin dimethyl sulfoxide + corn oil via subcutaneous route; MEL; n = 6), while the rest of the animals served as controls (dimethyl sulfoxide + corn oil; Control; n = 6). Males were subjected to routine examination on days -15, 0, 15, 30, 45, and 60. All examined dogs were subjected to Doppler screening, semen collection, and blood sampling. The MEL group showed a significant (P < 0.05) elevation in semen volume, concentration, percentage of sperm motility, and total sperm × 106 / ejaculate compared to other control males. Doppler indices as resistance (RI) and pulsatility (PI) indices declined (P < 0.05) from D 30 (1.02 ± 0.01) until day 60 (0.87 ± 0.02) of treatment. In MEL males, the peak systolic point of velocity (PSV; cm/sec) of the testicular artery elevated (P < 0.05) on day 60 (20.15 ± 0.99) compared to its value on day 0 (17.39 ± 1.84). On D 60, the levels of testosterone (T), estradiol 17-ß (E2), and nitric oxide (NO) elevated (P < 0.05). A negative correlation was detected between testicular volume, scrotal circumference (SC), T levels, Doppler indices, and velocities. In conclusion, single melatonin administration could improve testicular vascularization via increasing Doppler velocities and intratesticular colored areas. In addition, it could improve semen picture and steroids (T and E2) and nitric oxide.

Diseases of the Canine Prostate Gland

In dogs, the most frequent diseases of the prostate gland are benign prostate gland hyperplasia (BPH), acute and chronic prostatitis, squamous metaplasia, and prostate tumors. New diagnostic tools comprise diagnostic markers in the blood and urine, as well as advanced imaging methods. The therapy can be initialized with the 5α-reductase-inhibitor finasteride or an anti-androgenic compound, and prolonged with a long-acting gonadotropin-releasing-hormone (GnRH)-agonist such as deslorelin. In case of prostatitis, effective antibiotics must be applied for weeks. Antibiotics must be able to penetrate into the prostate tissue; fluoroquinolones, clindamycin, and erythromycin are good choices and are in addition effective against mycoplasms. The chronical prostatitis cannot be differentiated from a neoplasia by sonography; a biopsy, histological, and bacteriological examination are required. Tumors of the prostate gland are seldom and mostly occur in castrated but in intact dogs. For the final diagnosis, a biopsy must be taken. Partial and total resection of the prostate gland by use of laser technique is possible but coincedes with many side effects and the prognosis is still futile. Immunotherapy combined with NSAIDs, targeted noninvasive thermotherapy, BRAF gene inhibitors, or prostate artery chemoembolization are promising methods.

Correlation of Prostatic Artery Blood Flow Assessed by Doppler Ultrasonography with Semen Characteristics in Beagle Dogs

Simple Summary

This study examined the blood flow parameters of the prostate artery before dog ejaculation assessed by pulsed-wave Doppler ultrasound (PwD) changes. The main objective of this study was to characterize the vascular parameters of the prostatic artery in beagle dogs and to explore the potential use of Doppler ultrasonography as a complementary method in dog stud selection. These findings report differences between blood flow parameters in cranial and caudal locations of the prostatic artery in comparison to subcapsular and parenchymal locations. There was a high positive correlation of peak systolic velocity with total volume and sperm concentration. In conclusion, estimation of the PwD parameters of the cranial prostatic artery may be useful in the breeding evaluation of dogs.

Abstract

Pulsed-wave Doppler ultrasonography (PwD) is a method used to rapidly and noninvasively assess blood flow dynamics of the canine prostate. Modifications in gland vascularization can affect seminal plasma production and consequently sperm quality. The aim of this study was to determine the normal blood flow parameters of the prostate artery in beagle dogs and to analyze the correlations between vascular flow and semen quality characteristics. PwD was performed on five beagle dogs (5–6 years) measuring vascular features in four different locations of the prostatic artery (cranial, subcapsular, parenchymal and caudal); the measured features were peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI) and pulsatility index (PI). Ejaculates were obtained using digital manipulation and semen quality was evaluated by determining macroscopic (total volume, sperm-rich fraction volume, color and pH) and microscopic (sperm motility, morphology, viability and acrosome integrity) characteristics. The values of PSV, PI and RI in cranial and caudal prostatic arteries were significantly higher than in subcapsular and parenchymal arteries (p < 0.05). Moreover, a positive correlation of PSV value in the cranial region of the prostatic artery with total ejaculate volume (p < 0.01, r = 0.612) and sperm concentration (p < 0.01, r = 0.587) was determined. PI index was negatively correlated with sperm concentration (p < 0.01, r = −0.709). In conclusion, the results suggest that the prostatic artery blood flow parameters can affect macroscopic semen quality characteristics in healthy dogs.

Highlights on the Canine Prostatic Specific Esterase (CPSE): A diagnostic and screening tool in veterinary andrology

In the last years, the need to look for an accurate and precise diagnosis of prostatic diseases in dogs has grown. Among other diagnostic tools, the seric CPSE has been studied and identified as a valid and specific biomarker for prostatic disorders, since it can result significantly more elevated in dogs affected by several prostatic abnormalities, such as benign prostatic hyperplasia, bacterial prostatitis and prostatic carcinoma. Therefore, dosing CPSE in serum represents a new diagnostic and screening tool. Dosing CPSE in everyday clinical practice has three objectives: (a) the diagnosis of benign prostatic hyperplasia; (b) the preventive screening of prostatic disorders in healthy dogs; (c) the medical follow‐up in subjects with prostatic disorders during and after medical therapy. Neither circadian rhythms nor transrectal palpation performed during the andrological examination do affect CPSE. A sexual rest of at least 24 hr before dosing CPSE is recommended as it is affected by ejaculation.

Imaging of the male reproductive tract: Not so easy as it looks like

Diagnostic imaging is one of the most important tools in the breeding soundness evaluation of dogs and cats with reproduction problems. In recent years several imaging techniques have been developed, trying to aid the diagnosis and to differentiate between abnormal findings. This review presents the current knowledge on the imaging of normal and abnormal testes, spermatic cord, excurrent duct system, scrotum, accessory sex glands, penis and muscles for protrusion, erection and ejaculation of the dog and of cat. It also highlights the weak points and disadvantages of each imaging technique.

Ejaculation Effect on Canine Prostatic Specific Esterase Serum Concentration

Simple Summary

Canine andrology has become an important area within veterinary practice. In this field, the prostate plays a crucial role; it can be affected by several illnesses, strongly influencing male fertility. The diagnosis of such diseases relies on different procedures; among them, following the example of human medicine, the study of serum biomarkers has led to the use of Canine Prostatic Specific Esterase (CPSE) as a first-line tool. The CPSE is influenced neither by circadian rhythms nor by transrectal palpation. The present study aimed to evaluate the effect of ejaculation on CPSE, both in healthy animals and in subjects with prostatic disorders. Soon after ejaculation, CPSE concentrations in serum are significantly higher than basal ones; they then return to their original concentrations in 24 h. At all times, CPSE is higher in affected dogs than in normal subjects; however, some healthy patients could be misdiagnosed with prostatic disorders based on the CPSE concentrations measured soon after ejaculation. Thus, in accordance with recent reports on canine prostate ultrasonography, a sexual rest of minimum 24 h should be applied before a thorough examination of the male genital tract.

Abstract

Canine prostatic diseases are usually asymptomatic in their onset and often identified in advanced stages. Canine prostatic specific esterase (CPSE) represents an early serum marker for prostatic diseases, also in asymptomatic dogs. The present study aimed to identify the effects of ejaculation on serum CPSE. Twenty adult intact male dogs were enrolled. Blood samples were collected to measure CPSE concentrations before (T0), immediately after (T1), and 24 h post (T2) ejaculation. Data were compared within and between groups by ANOVA (p < 0.05). Dogs were divided in two equal groups: A (healthy: CPSE ≤ 52.3 ng/mL at T0) and B (suspected for prostatic disorders: CPSE > 52.3 ng/mL or diagnosed with symptoms of prostatic diseases: CPSE > 90 ng/mL). CPSE was shown to be statistically higher in group B than A at any time point. In both groups, CPSE showed a significant increase at T1, and no significant differences between T0 and T2. This study demonstrates a definite effect of ejaculation on CPSE concentration. Twenty-four hours post-ejaculation, CPSE returns to basal values. Such physiological effects of ejaculation should be considered when planning analyses of CPSE concentrations, i.e., by respecting a proper sexual rest.

Advanced ultrasound techniques in small animal reproduction imaging

Ultrasonography is the imaging technology of choice for the evaluation of the reproduction system and of pregnancy in both humans and animals. Over the past 10 years, there have been significant technological improvements of the equipment, while new technologies have been developed. Doppler, contrast-enhanced ultrasonography, elastography, and 3D/4D ultrasonography are advanced ultrasound techniques that have been designed as methods to increase the diagnostic sensitivity of two-dimensional (b-mode) ultrasound, and not as stand-alone tests. The basic physics as well as the advantages and limitations of these advanced ultrasound methods are briefly described. In the reproductive diagnostics of small animals, these techniques have gained an increased popularity as proved by the increased publication of several reports that are also briefly summarized in this review. Clinical applicability is to date limited because of a lack of research on the diagnostic value in concrete situations. Future research projects should focus also on standardization of the used techniques, on determination of thresholds to discriminate between healthy or diseases or fertile versus infertile and on the predictive value of advanced ultrasound findings. Continuing development and optimization of different ultrasound techniques as well as the increase of related scientific interest and worldwide research promises that the clinical interest on the use of advanced ultrasound techniques will increase in future.

The Effect of Dietary Supplementation of Vitamin E, Selenium, Zinc, Folic Acid, and N-3 Polyunsaturated Fatty Acids on Sperm Motility and Membrane Properties in Dogs

Sub-fertility represents a common challenge in canine reproduction. Different protocols, supplementing daily given quantities of micronutrients, were investigated to improve poor sperm concentration and/or function, which represent breeding major constraining factors in the canine species. Little information is available for dogs concerning the effect of a daily supplementation with a complex of vitamin E, zinc, selenium, folic acid, and n-3 polyunsaturated fatty acids (PUFA) on semen quality. Thus, the present study investigated this effect on semen motility and sperm membrane properties. Serial semen analyses from fourteen healthy normospermic dogs, fed with the same commercial diet, were performed on Days 0 (T0), 30 (T30), 60 (T60), and 90 (T90). Seven dogs were randomly included in the treatment (T) group, receiving a supplementation of vitamin E, zinc, selenium, folic acid, n-3 PUFA; and seven other subjects composed the control (C) group. Total Sperm Count (TSC), Computer-Assisted Sperm Analysis (CASA) indexes, mortality, and functional membrane integrity were assessed. The ANOVA compared results between groups and sampling times (p < 0.05). From T60, the supplementation significantly improved TSC, progressive motility, functional membrane integrity, and decreased mortality. Present results lead us to consider ameliorative effects of a two-month healthy diet supplementation on canine spermatozoa. The positive effects of the described balanced integration of micronutrients on sperm motility and prevention of oxidative stress should be considered, especially when decreased seminal parameters may result from inadequate intake, reduced absorption, increased losses or demand, or to attenuate the impact of age.