Changes of reproductive indices of the testis due to Trypanosoma evansi infection in dromedary bulls (Camelus dromedarius): Semen picture, hormonal profile, histopathology, oxidative parameters, and hematobiochemical profile

Expression and correlation of male reproductive hormone levels with abnormal semen liquefaction time

OBJECTIVE

To explore the reproductive hormone levels and their correlation in males with abnormal semen liquefaction time, providing evidence-based medical insights for the diagnosis and treatment of abnormal semen liquefaction.

METHODS

A total of 36 male patients who exhibited a sperm liquefaction time exceeding 60 min in the Maternal and Child Health Hospital of Hubei Province from January 2021 to January 2023 were included. They were classified into the delayed liquefaction group. During the same period, 138 male patients with a sperm liquefaction time of ≤60 min were assigned to a normal liquefaction group. Comparative analysis was performed on reproductive hormone levels between the two groups, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone (T), estradiol (E2), prolactin (PRL), as well as semen parameters such as normal morphology sperm rate, forward motility sperm rate, and sperm concentration. Pearson's correlation analysis was employed to investigate the relationship between reproductive hormones and semen liquefaction time. The effectiveness of biomarkers in predicting delayed semen liquefaction time was assessed using receiver operating characteristic (ROC) curves.

RESULTS

Patients with delayed semen liquefaction had significantly lower rates of normal morphology sperm, forward progressive motility, and sperm concentration when compared to patients with normal liquefaction. Significantly lower FSH, LH, and T levels were observed in patients with delayed semen liquefaction than those with normal liquefaction. Furthermore, a negative correlation was identified between serum FSH and T levels in male infertility patients and semen liquefaction time. The sensitivity of FSH for predicting semen liquefaction defects is 72.2%, whereas testosterone exhibits a sensitivity of 94.4%.

CONCLUSION

The semen liquefaction time of male infertility patients is closely correlated with semen parameters and reproductive hormone levels. Specifically, FSH and T exhibit a negative correlation with semen liquefaction time.

Protective effect of hydrogen-rich water on spermatogenesis in high-fat diet obese rats

Obesity can impair spermatogenesis by various mechanisms such as decreased sperm concentration and increased oxidative DNA damage. Hydrogen-rich water (HRW) possesses therapeutic antioxidant properties that may help offer protection to sperm. This study aimed to investigate the therapeutic potential of HRW on spermatogenesis dysfunction in rats with high-fat diet (HFD)-induced obesity. In this experiment, thirty male Wistar Albino rats were divided into three groups. 1) Control group: fed a normal diet, 2) Obese group: fed a HFD (45 % fat), and 3) HFD + HRW group: fed a high-fat diet and received HRW. HRW (1.5 mM) was administered orally every day. After 16 weeks, blood and tissue samples (testis and epididymis) were collected for biochemical and histopathological analysis. Serum LH, FSH and testosterone and oxidative and antioxidative markers, malondialdehyde (MDA), superoxide dismutase (SOD), and total thiol groups were measured in testis and epididymal tissues. The results showed that the HFD significantly increased food intake, body weight, and lee index, all of which were reduced in the HRW-treated obese group. Testis weight, sperm count, Serum LH and histological evaluation of testis including Sertoli and spermatogonia cell counts were significantly lower in the obese group but improved with HRW treatment. Additionally, HRW treatment increased the luminal diameter of seminiferous tubules, epididymal epithelia height, tissue SOD, and total thiol levels, while reducing MDA level in the testis. This study showed that administration of HRW can improve spermatogenesis in obese animals by reducing oxidative stress and ameliorating histological changes in the testis and epididymis, suggesting its potential benefits in combating high-fat diet-induced reproductive dysfunction.

Breeding soundness evaluation, a tool for improving the sustainability of dromedary camel (Camelus dromedarius) breeding systems in arid and semi-arid lands

The reduced fertility of dromedary camel (DC) bulls, whether temporary or permanent, poses a significant threat to the sustainability of camel breeding systems and, consequently, to food security in arid and semi-arid regions. Therefore, it is crucial to assess dromedary camel breeding bulls to ensure they can fulfill their reproductive potential. However, standardized clinical and andrological evaluation procedures, known as breeding soundness evaluations, as well as an efficient reporting system, are currently lacking for this species. In this narrative review, the most important aspects related to bull fertility and breeding soundness evaluation have been described and adapted to the dromedary camel bull in order to provide a standardized procedure for an efficient clinical and andrological evaluation in this species, taking into account its unique characteristics. Additionally, a herd and bull examination record form, divided into four main sections, has been provided, for the first time, to ensure efficient and consistent data collection and reporting. If implemented on a large scale, the clinical evaluation procedures and data collected by the recording forms provided in this study, would help to identify factors associated with the impairment of reproductive efficiency in dromedary herds and bulls worldwide.

Computer-assisted sperm analysis of the epididymal spermatozoa in dromedary camels suffering from penile and preputial pathological problems

Dromedary camels are the most vulnerable animals to penile and preputial pathology due to the aggressive nature of mating and injuries during transit, which could impair the semen quality. Hence, this study was performed to monitor the penile and preputial pathological conditions in male dromedary camels, as well as their impact on epididymal spermatozoa, by utilizing computer-assisted sperm analysis (CASA) and correlation analysis with testosterone concentrations. A total of 60 male dromedary camels were examined for penile and preputial pathological problems. The camels were grouped based on the absence or presence of the pathology conditions: (i) camels with normal penis and prepuce, (ii) camels with balanoposthitis, (iii) camels with penile trauma, (iv) camels with prolapsed prepuce, (v) camels with phimosis, and (vi) camels with penile tumors. The results revealed that there were significant increases in sperm concentration (Conc., M/ml), curvilinear velocity (VCL, μm/s), eat-cross frequency (BCF, Hz), and straightness (STR, VSL/VAP) of the epididymal tail semen in camels with prolapsed prepuce. There were increases in progressive motility (PR), VCL, straight line velocity (VSL, μm/s), average path velocity (VAP, μm/s), BCF, and STR in the sperms of the group with phimosis, but the differences were non-statistically significant. Furthermore, the CASA parameters of the epididymal tail semen in the group with penile tumor showed an increase in PR (%), VCL, VSL, VAP, BCF, and STR (%) compared to those in the group with normal penis and prepuce. However, the CASA parameters of the epididymal body in the group with penile tumor showed a significant increase in vitality, total motility (TM), non-progressive motility (NP), mean angular degree (MAD), linearity (LIN, VSL/VCL), VSL, amplitude of lateral head displacement (ALH, μm), VAP, BCF, and STR compared to those in the group with normal penis and prepuce. There were no discernible differences in testosterone concentrations among the groups. There was a negative correlation (p < 0.05, r = 0.411-0.459) between testosterone concentration and CASA parameters of the epididymal tail semen in camels with penile and preputial pathological conditions. In comparison, there were no discernible differences in correlation (p > 0.5, r = 0.074-0.360) between testosterone concentration and CASA parameters of the epididymal body and head semen in camels with penile and preputial pathology. In conclusion, the semen quality of male dromedary camels could be affected by the penile and preputial pathological problems, while the testosterone concentration was not affected.

Optimizing the preparation of paraffin sections from stallion testes

The preparation of paraffin sections is an important experimental technique in animal histological research, and key factors that determine the quality of a section include the dehydration time, waxing time, and drying temperature of the paraffin section. Paraffin sections obtained from testis tissue of adult horses exhibited higher quality with clear tissue structure and complete cell morphology after they underwent gradient dehydration for 6 hours, were immersed in wax for 60 minutes, and were dried in a 75-degree oven for 15 minutes. The detailed, optimized procedures that are developed in the current study may simplify histological experiments and research on equine testes.

Impact of trypanosomiasis on male camel infertility

Introduction

Blood parasitism is a significant clinical disease that silently undermines the livestock industry, particularly affecting camels. This study aimed to assess the prevalence of Trypanosoma evansi in Arabian camels (Camelus dromedarius) and its impact on infertility by examining serum protein fractions, lipids, reproductive indices, and the expression of heat shock protein (HSP70) during breeding season.

Methods

A total of 107 male post-pubertal camels, aged between 5 and 10 years, were collected randomly from slaughtering house in Assiut Governorate, Egypt.

Results

Microscopic and serological examinations revealed that 23.4% (25/107) of the camels were infected with T. evansi. Infected camels exhibited a highly significant increase in total serum protein. The assessment of dyslipidemia, measure as binary variables for lipid profiles (cholesterol, triglycerides, HDL, and LDL), indicated a nonsignificant increase in risk of dyslipidemia in infected camels compared to healthy camels. Proteomic analysis identified four major protein fractions in the infected camels compared to healthy camels with molecular weights of 181.72, 87.59, 30.5, and 19.5 kDa using SDS electrophoresis. Testicular tissue of the infected camels showed degeneration and necrotic changes in seminiferous tubules and interstitial tissue, along with edema and congestion. There was a significant reduction in the diameter of seminiferous tubules and germinal epithelium height. A marked reduction in testosterone levels and a high expression of HSP70 in spermatogonia, spermatocytes, Sertoli cells, and Leydig cells were observed.

Discussion

Consequently, a combination of physiological and hormonal analyses may serve as a reliable indicator of Trypanosoma infection.

Poor semen quality is associated with impaired antioxidant response and acute phase proteins and is likely mediated by high cortisol levels in Brucella-seropositive dromedary camel bulls

Brucellosis in dromedary camel bulls leads to either temporary or permanent loss of fertility. Camel brucellosis is associated with both orchitis and epididymitis. However, the clinical signs of camel brucellosis are not clear as those in cattle. Therefore, this study aimed to diagnose camel brucellosis based on a serological screening using Rose Bengal plate test (RBPT) followed by competitive ELISA. To understand the impact of brucellosis on camel bull fertility, this study aimed to examine the semen characteristics, evaluate the testicular histopathology, examine hormonal profile, antioxidants and acute phase proteins (APP). A total of 150 mature bulls were used in this study. Blood samples were collected for serological, hormonal, and biochemical analysis. This study revealed that 6.6% and 7.3% of the examined bulls were Brucella-seropositive using RBPT and competitive ELISA, respectively. The Brucella-seropositive dromedary bulls showed poor semen quality, pathological changes orchitis, and lower testosterone. Moreover, our findings showed a higher cortisol level, and significant impairments in the measured APP and antioxidants in Brucella-seropositive bulls. In conclusion, the Brucella-seropositive dromedary bulls showed lower fertility due to poor semen quality and lower testosterone levels. Such lower fertility is likely mediated by high cortisol levels, and impaired APP and antioxidants' defense response.

Camel filariasis (Dipetalonema evansi) and its association with clinical balanoposthitis with reference to prominent changes in clinical findings, serum testosterone, semen analysis, and testicular histopathology

BACKGROUND

Camel filariasis induced variable clinical syndromes characterized by fever, lethargy, localized dermal lesions, loss of condition, and testicular and scrotal swelling. The objective of the present work focused on clarifying the diagnostic importance of clinical findings, serum testosterone, and semen analysis as well as blood smear and testicular histopathology as a differential tool between only balanoposthitis without filariasis male camels group (OnlyBpgr) and balanoposthitis-filariasis infected male camels group (BpFlgr). The study also monitored the associations between the severity of ticks' infestations in investigated male camels and the occurrence of balanoposthitis only or balanoposthitis with filariasis.

RESULTS AND CONCLUSIONS

The study reported significant correlation between serum testosterone, serum cortisol, and sperm vitality and abnormalities percentages. The study included male camels (n = 250) classified into three groups: healthy control group (Contgr; n = 30), OnlyBpgr (n = 210), and BpFlgr (n = 10). These male camels were clinically and laboratory examined, and skin scraping tests and testicular histopathology were conducted. The study confirmed the association of the changes in clinical findings, whole blood picture, serum testosterone, serum cortisol, and semen analysis, with OnlyBpgr and BpFlgr. These changes were more prominent in BpFlgr than in OnlyBpgr. Skin scraping test results revealed a higher severity of live ticks' infestation in BpFlgr than in OnlyBpgr because, unlike OnlyBpgr, all camels in BpFlgr (n = 10) were suffering from live ticks' infestation. It also concluded the higher efficacy of histopathology of testicular tissues in male camels as a diagnostic tool for adult filaria in balanoposthitis-affected male camels than blood smear because all cases of camel filariasis in the current work were negative for microfilaria on microscopic examination of diurnal blood smear as well as testicular histopathology revealed detection of adult filaria in all camel filariasis associated with balanoposthitis. Strong correlation relationships were demonstrated between serum testosterone, serum cortisol, and semen analysis results. Positive correlations were reported between serum testosterone levels and sperm vitality percentages. However, negative correlations were stated between serum testosterone and each of serum cortisol and sperm abnormalities either in Contgr, OnlyBpgr, or BpFlgr.

Histopathology and virulence of an in vitro-adapted Trypanosoma evansi TEDC 953 strain (Thailand isolate) in mice

Background and Aim

Trypanosoma evansi is a blood and tissue protozoan parasite affecting domestic and wild animals. The T. evansi Thai strain, namely, T. evansi from dairy cattle number 953 (TEDC 953) strain, has been successfully isolated from dairy cattle and cultivated in vitro. The in vitro-cultivated parasite is useful for biological studies, evaluation of novel chemotherapeutic agents, and production of antigens for diagnostic tests. This study aimed to observe the histopathology and virulence of an in vitro-adapted T. evansi TEDC 953 strain in vivo.

Materials and Methods

The histopathology and virulence of the TEDC 953 strain were clarified in mice. Six mice were infected with 1 × 105 trypomastigotes of TEDC 953 strain intraperitoneally, and four mice were in the negative control. Parasitemia was monitored daily, and the mice were euthanized on 30 days post-infection (DPI). Internal organs were collected for histopathological examination using hematoxylin and eosin staining.

Results

Histopathological lesions were found in the liver, lung, heart, kidney, spleen, and brain of the inoculated mice. The main histopathological feature was lymphoplasmacytic inflammation in parenchyma and perivascular areas of multiple organs, and the severity of histopathological changes was related to the presence of trypomastigotes in the regional vessels. Granulomatous inflammation was seen in meninges, pleura, renal capsule, renal pelvis, and spleen of some infected mice. Four mice died at 17, 24, 26, and 27 DPI with an average parasitemia of 4.05 × 1011 trypomastigotes/mL. The average survival time was 23.5 DPI (mice = 4).

Conclusion

This study confirmed that the TEDC 953 strain is infectious and pathogenic in mice after the continuously cultivated in vitro. To replace the use of experimental animals, the in vitro-cultivated parasite can be used instead in further studies.

Infection of West African dwarf rams with Trypanosoma brucei brucei and Trypanosoma congolense significantly alter serum electrolytes, redox balance, sperm parameters, and gonadal morphology

Trypanotolerance of the West African dwarf (WAD) breeds may not rule out significant pathophysiological changes that may affect productivity. In this study, the effects of infection of WAD rams with Trypanosoma brucei brucei (Tbb) and Trypanosoma congolense (Tc) on their serum levels of electrolytes [calcium, phosphorus, sodium, potassium]; oxidative stress markers [superoxide dismutase (SOD), malondialdehyde (MDA)]; and sperm parameters [sperm count, motility, vitality, and morphology] were investigated. Fifteen WAD rams, assigned to 3 groups (A, B & C) of 5 rams each, were used for the study. Group A rams were infected with Tbb, while Group B rams were infected with Tc, both intraperitoneally, at the dose of 10⁶ trypanosomes/animal. Group C rams served as the uninfected control. The infections were monitored for 70 days. Serum calcium levels were significantly (p < 0.05) lower in Tbb and Tc infected rams compared to the control throughout the study. Serum sodium was significantly (p < 0.05) higher in the Tb infected rams compared to the Tc infected and control rams on days 14 and 28 PI. Serum SOD activity decreased while MDA levels increased in both infected groups of rams. Tbb infected rams were azoospermic, while Tc infected rams had lower sperm motility, vitality and concentration, and higher number of abnormal sperm cells compared to the control. Necrotic and inflammatory lesions occurred in the testis and epididymis of both infected rams. These results suggest that despite trypanotolerance, trypanosome infections in the WAD rams significantly impact on health and reproduction.

A meta-analysis of impacts of immune response and infection on oxidative status in vertebrates

Inferring from patterns observed in biomedical research, ecoimmunological theory predicts that oxidative stress is a ubiquitous physiological cost that contributes to generating variation in immune function between individuals or species. This prediction is, however, often challenged by empirical studies testing the relationship between immune response or infection and oxidative status markers. This points out the importance of combining ecological immunology and oxidative stress ecology to further our understanding of the proximate causes and fitness consequences of individual variation in health, and adaptability to natural and anthropogenic environmental changes. I reviewed evidence and performed phylogenetic meta-analyses of changes in oxidative status markers owing to either injection of an antigen or infection in captive and free-living vertebrates (141 studies, 1262 effect sizes, 97 species). The dataset was dominated by studies on fish, birds and mammals, which provided 95.8% of effect sizes. Both antigen injection and parasite exposure were associated with changes of oxidative status. There were significant effects of taxonomic class and experimental environment (captivity vs. wild). In contrast with my predictions, age category (young vs. adult), study design (correlational vs. experimental) and proxies of pace of life (clutch size, litter size, and body mass; for birds and mammals only) were negligible in this dataset. Several methodological aspects (type of immunostimulant, laboratory assay, tissue analysed) showed significant effects on both strength and direction of effect. My results suggest that alterations of oxidative status are a widespread consequence of immune function across vertebrates. However, this work also identified heterogeneity in strength and direction of effect sizes, which suggests that immune function does not necessarily result in oxidative stress. Finally, this work identifies methodological caveats that might be relevant for the interpretation and comparability of results and for the application in conservation programs.

Seroprevalence and immunological characterization of Trypanosoma evansi infection in livestock of four agro-climatic zones of Himachal Pradesh, India

Trypanosoma evansi, a hemoflagellate protozoan parasite, causes wasting disease called surra in wide range of animals. Although the organism has been reported from various parts of India, data generated from organized epidemiological study is still in infancy in majority states of India. In the present study, livestock of Himachal Pradesh, India, was targeted for epidemiological investigation of T. evansi infections. A total of 440 equines and 444 cattle serum samples were collected from four agro-climatic zones. Furthermore, serum samples of 280 buffaloes from three different agro-climatic zones of Himachal Pradesh were also collected and evaluated for the presence of T. evansi infection by indirect ELISA. Data generated showed higher prevalence in buffalo (23.57%) followed by cattle (22.52%) and equines (1.82%). Disease was found to be more prevalent (P < 0.01) in cattle of lower altitude as compared to those of higher altitudes. No significant variation was seen in prevalence of disease on the basis of age and sex of the animals. Serum biochemical analysis revealed increased levels of BUN in T. evansi-infected equines. Levels of liver function enzymes such as ALT/GGT and AST were found to be significantly elevated (P < 0.01) in seropositive animals whereas glucose levels were significantly lower in surra-seropositive animals as compared to seronegative animals. Immunoblot analysis of whole cell lysate (WCL) antigen of T. evansi using surra-seropositive samples of equines showed immunodominant bands in the range of 100-25 kDa. Bovine-seropositive samples recognized polypeptide bands in the range of 85-32 kDa, including protein clusters of 52-55 and 48-46 kDa. Polypeptide cluster of 62-66 kDa was found common in seropositive samples of bovines and equines from all agro-climatic zones. T. evansi was found to be highly prevalent in livestock of Himachal Pradesh, and thus, there is dire need for designing of proper control strategies against surra.

Time-Dependent Testicular and Epididymal Damage in Rabbit Bucks Experimentally Infected with Trypanosoma Brucei Brucei

This study was designed to determine the progressive pathological changes in the testis and epididymis of rabbit bucks experimentally infected with Trypanosoma brucei brucei (T. brucei). Fifteen local rabbit bucks were divided into 2 groups comprising 8 bucks in group A and 7 bucks in group B. Bucks in group A were infected intraperitoneally with approximately 1.0×106 of T. brucei while bucks in group B served as the uninfected control. The bucks were closely monitored for clinical signs of trypanosomosis from the time of infection till the end of the study. One buck from each group was humanely sacrificed on days 9, 19, 29 and 38 post-infection (pi) and its testis and epididymis were examined for pathological changes. At post mortem, no gross lesions were observed in the infected bucks except for adhesion of the testis and epididymis to the scrotum on days 29 and 38 pi. There were no histological changes in the testis and epididymis of the infected buck sacrificed on day 9 pi apart from mild depletion of the epididymal sperm reserve. The buck infected on day 19 pi had moderate testicular degeneration but the epididymis was devoid of sperm reserve. Severe testicular and epididymal degeneration was observed in the buck on days 29 and 38 pi. The testis and epididymis of bucks from the control group were normal with evidence of spermatogenic activities and full epididymal sperm reserve throughout. The study shows that infected bucks were unfit for breeding from day 19 pi.

Review on trypanosomiasis and their prevalence in some country on the Red Sea

Trypanosomiasis is a protozoan infection affecting both human and animals in almost all parts of the world. It can affect a very large range of domestic and wild hosts including camelids, equines, cattle, buffaloes, sheep, goats, pigs, dogs and other carnivores, deer, gazelles and elephants. This review paper was designed to address the effect of this economically important disease in countries on the Red Sea, especially in Egypt, Sudan, Somalia, and Saudi Arabia during the period 2010 to 2020. The prevalence of trypanosomiasis is different between these countries due to different types of diagnostic methods (Giemsa-stained blood smears, Hematocrit centrifugation, Serological test, and molecular analysis PCR) used and differential distribution of vector (Tse tse) flies. In current review, retrospective studies of published literature on distribution and prevalence of Trypanosoma evansi infection in the Red Sea Countries was conducted [Google Scholar and PubMed were used to retrieve the published literature from 2000-2020. A total of 77 published articles met the eligibility criteria and were reviewed. A total of 16 reports have been reported on the prevalence and distribution of Trypnosoma evansi infection in the Red Sea Countries have been from 2010-2020]. According to the published literature, we can say that trypanosomiasis in camels are more prevalent in Sudan than in other countries, followed by 17% and 51.78% in both clinical and non-clinical cases. Hence, the reliable diagnostic tests should be used for rapid treatment or control of the disease as if not treated appropriately in early-stage, can lead to death of the camels.