Evaluation of the Breeding Soundness of Male Camels (Camelus dromedarius) via Clinical Examination, Semen Analysis, Ultrasonography and Testicular Biopsy: A Summary of 80 Clinical Cases

Region-specific gene expression profile in the epididymis of high- and low-fertile dromedary camels

The scenario of the fertile spermatozoa with high fertilizing capability is basically dependent on gene expression-based epididymal function. The current investigation aimed to declare the varied expression of different candidate genes (PLA2G4D, LCN15, CLUAP1, SPP1, AQP12B, DEFB110 and ESR1) relevant to spermatozoa features between the different epididymal segments in the mature dromedary camels (n = 30). Scrotal contents were collected post-slaughtering, during the breeding season and the epididymis was separated from the testicles and divided into three segments (caput, corpus and cauda) based on its morphology and anatomical characteristics. Epididymal spermatozoa were harvested from each epididymal portion and evaluated for motility, count, viability and morphology. Samples were grouped depending on their epididymal sperm cells features into high-fertile (n = 15) and low-fertile (n = 15) groups. The gene expression of the candidate genes was defined in the isolated RNA from each epididymal portion tissue. The segmental sperm motion and count were significantly (p < .05 and p < .01) higher in the three epididymal parts of high-fertile camels than the lower ones. There were some candidate genes markedly up-regulated in its expression in epididymal head of high-fertile camels (PLA2G4D and LCN15) and low fertile (CLUAP1), while others in the body region of the high-fertile group (SPP1, AQP12B and DEFB110). Nevertheless, ER1 did not differ in the expression among the epididymal segments. In conclusion, the variant expression patterns of these epididymal genes in relation to the regional spermatozoa features might suggest important roles of these genes in sperm maturation process in the epididymis and focusing more interest on their potential utility as markers for male camel fertility prediction.

Abundance of selected genes implicated in testicular functions in Camelus dromedarius with high and low epididymal semen quality

Studying testicular genes' expression may give key insights into precise regulation of its functions that influence epididymal sperm quality. The current study aimed to investigate the abundance of candidate genes involved in the regulation of testicular functions specially those regulate sperm function (PLA2G4D, SPP1, and CLUAP1), testicular steroidogenic function (ESR1 and AR), materials transport (AQP12B and LCN15), and defense mechanisms (DEFB110, GPX5, SOCS3, and IL6). Therefore, blood samples and testes with epididymis were collected from mature middle-aged (5-10 years) dromedary camels (n = 45) directly prior and after their slaughtering, respectively, during breeding season. Sera were evaluated for testosterone level and testicular biometry was measured with caliper. The epididymal tail semen was evaluated manually. Samples were distinguished based on testosterone level, testicular biometry, as well as epididymal semen features into high and low fertile groups. Total RNA was isolated from testicular tissues and gene expression was done using Quantitative Reverse Transcription Polymerase Chain Reaction (qRT-PCR). Results revealed that testosterone levels were significantly (P < 0.005) higher in camels with good semen quality than those of low quality. There was a significant (P < 0.0001) increase in testicular weight, length, width, thickness, and volume in high fertile than low fertile camels. PLA2G4D, SPP1, CLUAP1, ESR1, AR, AQP12B, LCN15, DEFB110, GPX5, and SOCS3 genes were upregulated (P < 0.001), and IL6 gene was downregulated (P < 0.01) in the testes of high fertile camels compared to the low fertile one. Thus, it could be concluded that examined genes might be valuable monitors of testicular functional status and fertility in dromedary camels.

Aetiological analysis and diagnosis of reproductive disorders in male dromedary camels

The purpose of this paper was to analyse the aetiology and methods of diagnosing reproductive disorders in male dromedary camels. Male camel infertility manifests as one of three conditions: post-coital infertility (IG), inability to copulate (IC) and lack of sexual desire (LSD). IG is mainly a testicular disorder that is linked to a deteriorated seminogram, arrested spermatogenesis, Sertoli cell-only syndrome and testicular degeneration. For IG diagnosis, semen analysis, testicular biopsy and fine-needle aspiration are gold standards. Testicular ultrasonography was generally inefficient. High serum FSH was found in IG camels with oligo- and azoospermia, implying primary spermatogenesis defects. The testis-expressed protein (TEX101) and the epididymis-expressed protein (ECM1) are reliable biomarkers for distinguishing between obstructive and non-obstructive azoospermia. IC manifests in two forms: phimosis (PHI) and erectile dysfunction (ED). PHI is frequently linked to preputial and penile pathologies, as well as leucocytosis, neutrophilia and elevated nitric oxide metabolites. The majority of camels with ED have normal genital organs, and the condition is associated with an increase in cardiac troponin I. LSD is a rare disorder brought on by hormonal imbalances, high temperatures, stress and debilitating diseases. In conclusion, IG diagnosis necessitates semen analysis, testicular biopsy or fine-needle aspiration, and FSH testing, whereas IC diagnosis requires preputial and penile examinations. Diagnostic aids include serum and seminal biomarkers.

Effect of heavy metals arsenic, cadmium, and lead on the semen variables of dromedary camels (Camelus dromedarius)

In this study, there was investigation of the effect of heavy metals on the fertility of dromedary camels. Fourteen camels at the Camel Research Center, King Faisal University, and 41 infertile dromedaries admitted to the Veterinary Teaching Hospital were used for semen evaluation during the breeding season. Seminal plasma and blood serum were collected from all males until analysis. Concentrations of three heavy metals [arsenic (As), cadmium (Cd), and lead (Pb)] were determined in the seminal plasma and serum using an atomic absorption spectrophotometer. The results indicate there are differences (P <  0.05 - P < 0.01) in pH, sperm motility, sperm concentration, and sperm abnormalities between the fertile and infertile male camels. In seminal plasma, there were marked differences (P < 0.01- P < 0.0001) between the control and infertile male camels in As, Cd, and Pb concentrations. In serum, there were differences (P <  0.01 - P <  0.001) between the fertile and infertile camels in serum As, Cd, and Pb concentrations. There was a positive correlation (P <  0.05; r = 0.77 and r = 0.94, respectively) between serum and seminal plasma concentrations of both As and Cd in the infertile dromedaries. In the control group, there was a positive correlation (P <  0.05; r = 0.70) between seminal plasma concentrations of Cd and percent sperm abnormalities. In conclusion, relatively greater seminal plasma and serum concentrations of As, Cd, and Pb are associated with lesser values for semen quality variables and infertility in dromedary camels.

The relationship between seminal plasma and serum trace elements and semen parameters of dromedary camels (Camelus dromedarius)

A total of 14 camels of known fertility (controls) at the Camel Research Centre, King Faisal University and 41 infertile dromedaries brought to the Veterinary Teaching Hospital were used in this study during the breeding season. Seminal plasma and serum were obtained from all males, and stored at -80°C until analysis. Concentrations of six trace elements (manganese [Mn], zinc [Zn], iron [Fe], selenium [Se], copper [Cu] and chromium [Cr]) were estimated in the seminal plasma and serum using an atomic absorption spectrophotometer. Results showed significant (p < 0.05 and p < 0.01) differences in semen pH and sperm motility, concentration and abnormalities between the control and infertile dromedaries. In seminal plasma, a significant (p < 0.01) difference in Fe concentrations (7.792 ± 1.567 vs. 61.259 ± 11.967 mg/L) and significant (p < 0.05) differences in Zn (24.763 ± 8.206 vs. 83.981 ± 4.972 mg/L) and Cu (1.653 ± 0.348 vs. 7.905 ± 1.134 mg/L) concentrations existed between the control and infertile dromedaries, respectively. In serum, there were significant (p < 0.05) differences in Fe (6.237 ± 0.695 vs. 151.121 ± 27.604 mg/L) and Cu (24.703 ± 4.195 vs. 6.375 ± 0.644 mg/L) concentrations and a significant (p < 0.01) difference in Zn concentrations (17.086 ± 1.606 vs. 90.422 ± 4.347 mg/L) between the fertile and infertile camels, respectively. There were significant (p < 0.05) positive (r = 0.51) and negative (r = -0.54) correlations between Zn concentrations in seminal plasma and both sperm motility and sperm abnormalities, respectively. In conclusion, seminal plasma and serum trace elements of Fe, Zn and Cu influenced the semen parameters and fertility of dromedary camels. Low concentrations of Fe, Zn and Cu in the seminal plasma were associated with normal fertility in dromedaries.

Serum biochemical profile and molecular detection of pathogens in semen of infertile male dromedary camels (Camelus dromedarius)

Detection of pathogens in the semen of camels has not been completely elucidated. Therefore, the current study aimed to determine the association of some economically important pathogens with infertility in 94 male infertile camels through molecular detection and estimation of selected biochemical parameters in serum of these animals compared with a control non infected fertile animals (n=40). PCR analysis of semen samples of infertile camels indicated that, four potential pathogens namely Mycoplasma spp., Leptospira spp., Brucella melitensis, and Bovine viral diarrhea virus (BVDV) were detected in 50 semen samples of infertile camels whereas, 44 semen samples of infertile camels were free of pathogens and all tested semen samples were negative for bovine herpes virus 1, Salmonella spp. and Trypanosoma evansi. Single and mixed infection was detected in 88% and 12% of the infected semen samples, respectively. Mycoplasma spp., Leptospira spp., Brucella and Bovine viral diarrhea virus infection represented 66%, 27.2%, 4.5% and 2.3% of the single infected semen samples. Mycoplasma spp.+Leptospira spp. and Mycoplasma spp.+Brucella spp. were detected in 83.3% and 16.7% of mixed infected semen samples, respectively. Testosterone concentration decreased significantly in infertile infected camels compare to both control and infertile non infected animals that remained comparable. The current findings reported the molecular detection of mixed infection in camel semen for the first time. Mycoplasma spp. is the most widely recognized microorganism in the present study and together with Leptospira spp., Brucella spp. and Bovine viral diarrhea virus, might be associated with infertility in dromedary camels.