The prevalence of selected vector-borne diseases in dromedary camels (Camelus dromedarius) in the United Arab Emirates.

Vector-borne diseases (VBDs) affecting dromedary camels (Camelus dromedarius) have considerable importance in the United Arab Emirates (UAE) because of the consequences associated with production decline and economic losses. Our study aimed to determine the prevalence of selected VBDs in camels in the UAE and identify risk factors. This research is currently affected by the low number of epidemiological molecular surveys addressing this issue. Blood samples were obtained from 425 dromedary camels from different locations across the UAE. Whole genomic DNA was isolated, and PCR screening was done to detect piroplasmids (Babesia/Theileria spp.), Trypanosoma spp., and Anaplasmataceae spp. (Anaplasma, Ehrlichia, Neorickettsia and Wolbachia spp.). Amplicons were sequenced, and phylogenetic trees were constructed. Trypanosoma sequences were identified as T. brucei evansi, whereas Anaplasmataceae sequences were identified as A. platys-like. All camels were negative for Babesia/Theileria spp. (0%); however, 18 camels were positive for T. b. evansi (4%) and 52 were positive for A. platys-like (12%). Mixed infection with T. b. evansi and A. platys-like was found in one camel. Statistical analyses revealed that camels with a brown coat colour were significantly more prone to acquire the A. platys-like strain compared with those having a clearer coat. A similar finding was observed when comparing urban moving camels with desert indoor and urban indoor camels. Continuous disease surveillance is required to ensure and maintain the good health status of the camels in the UAE. Nonetheless, the risk of disease outbreak remains if the misuse of drugs continues.

Innate and adaptive immune-directed tumour microenvironment in pancreatic ductal adenocarcinoma.

One of the most deadly and aggressive cancers in the world, pancreatic ductal adenocarcinoma (PDAC), typically manifests at an advanced stage. PDAC is becoming more common, and by the year 2030, it is expected to overtake lung cancer as the second greatest cause of cancer-related death. The poor prognosis can be attributed to a number of factors, including difficulties in early identification, a poor probability of curative radical resection, limited response to chemotherapy and radiotherapy, and its immunotherapy resistance. Furthermore, an extensive desmoplastic stroma that surrounds PDAC forms a mechanical barrier that prevents vascularization and promotes poor immune cell penetration. Phenotypic heterogeneity, drug resistance, and immunosuppressive tumor microenvironment are the main causes of PDAC aggressiveness. There is a complex and dynamic interaction between tumor cells in PDAC with stromal cells within the tumour immune microenvironment. The immune suppressive microenvironment that promotes PDAC aggressiveness is contributed by a range of cellular and humoral factors, which itself are modulated by the cancer. In this review, we describe the role of innate and adaptive immune cells, complex tumor microenvironment in PDAC, humoral factors, innate immune-mediated therapeutic advances, and recent clinical trials in PDAC.

Comprehensive mapping of the exterior architecture of the dromedary camel brain.

The morphological perspective of the camel brain remains largely unexplored. Therefore, studying the topography of the camel brain is of crucial importance. This study aimed to provide a detailed color-coded topographic representation of the camel brain's gross anatomy and nomenclature, showing its various gyri and sulci and their borders. We compared them to previously known information to develop a detailed description of camel brain exterior architecture. Our research identified distinctive gyri and sulci with discrete positions and surrounding structures, allowing us to define sulci boundaries and establish logical gyri nomenclature. This study uncovered previously overlooked gyri and sulci and improved descriptions of specific sulci. The ectomarginal sulcus, splenial sulcus, splenial gyrus, and ectogenual gyrus are a few examples. These findings highlight several unique anatomical features of the dromedary brain, which can guide future research. By providing a comprehensive examination of the distinctive exterior anatomical features of the camel brain, this study may serve as a point of convergence for all researchers, providing more accurate identification of the gyri and sulci.

Comprehensive anatomical study of meningeal arteries in dromedaries.

This study provides a detailed, in-depth analysis of the anatomy, topography, and branching patterns of the meningeal arteries in dromedary camels, a subject that has not previously been thoroughly studied in animals, providing insight into the intricate biological adaptations that allow them to survive in harsh environments. By precisely examining 20 heads obtained from freshly slaughtered dromedaries, we revealed the origins and topologies of the rostral, middle, and caudal meningeal arteries using advanced casting techniques for precise rendering. Our findings indicate that the rostral meningeal artery derives from the external ethmoidal artery and primarily supplies the rostrodorsal region of the frontal lobe. The middle meningeal artery provides blood to approximately two-thirds of the brain meninges. The caudal meningeal artery is derived from the occipital artery and supplies the meninges covering the cerebellum, caudal part of the falx cerebri, and tentorium cerebelli. Significantly, our study revealed the presence of accessory branches originating from the rostral epidural rete mirabile, a finding not previously described in the existing literature. These branches supply the meninges of the frontal and lateral regions of the frontal lobes. This novel study advances our understanding of the meningeal arteries in dromedaries and has significant implications for advancements in veterinary neuroscience.

Arthrocentesis approaches to the phalangeal joints of the one humped camel (Camelus dromedarius).

Irrespective of the exceptional adaptation of dromedaries to harsh environmental conditions, they remain highly susceptible to joint lameness resulting from a range of diverse factors and conditions. The joints most often affected by traumatic osteoarthritis in dromedaries are the metacarpophalangeal and metatarsophalangeal joints. A comprehensive understanding of joint anatomy and topography of the dromedary is required to perform arthrocentesis correctly on affected joints. Forty-two distal limbs were taken from 28 camels and studied by gross dissection, casting, ultrasonography, and computed tomography (CT). Representative three-dimensional models of the joint cavities, recesses, and pouches were obtained using different casting agents. This study provides a detailed description of dorsally, axially, and abaxially positioned joint recesses, as well as palmar/plantar positioned joint pouches. The safety and feasibility of the different arthrocentesis approaches were evaluated. The traditional dorsal arthrocentesis approach of the metacarpophalangeal, metatarsophalangeal, proximal interphalangeal, and distal interphalangeal joints, has limitations due to the risk of damaging the tendon structures and articular cartilage, which can lead to joint degeneration. A lateral arthrocentesis approach via the proximal palmar/plantar pouches of the metacarpophalangeal/metatarsophalangeal and proximal interphalangeal joints is recommended. This approach eliminates the potential needle injury to the articulating joint cartilage and other surrounding joint structures, such as tendons, blood vessels, and nerves.

Mapping the branching pattern of the middle cerebral artery in the camel (Camelus dromedarius): a comprehensive anatomical analysis.

The complex branching structure of the middle cerebral artery serves as a crucial component in the blood supply to the cerebral cortex, playing a key role in sustaining brain function and overall neurological health in mammals. A thorough understanding of the branching structure of the middle cerebral artery is required for the advancement of veterinary medicine and neuroscience research. In this study, we provide the first comprehensive anatomical analysis of the branching structure of the middle cerebral artery (MCA) in the dromedary brain. To date, no study has examined the MCA branches in dromedaries. By examining 80 cerebral hemispheres from freshly slaughtered male dromedary camels aged 2-6 years, we aimed to explain the origin, course, and branching patterns of the MCA in the dromedary camel. Advanced casting techniques using colored latex, epoxy paint, and liquid plastic have been used to create precise renderings of the MCA structure. Our findings revealed that the MCA is the principal branch of the rostral cerebral artery and serves as the primary blood supply to the telencephalon in dromedaries. The main trunk of the MCA splits into several cortical branches, each supplying blood to a specific cerebral hemisphere. These branches comprise the rostral and caudal olfactory arteries; orbital artery; superior, middle, and inferior frontal arteries; rostral, middle, and caudal parietal arteries; and dorsal, middle, and ventral temporal arteries. This groundbreaking work considerably advances our understanding of the dromedary cerebrovascular system by providing insightful information on the anatomy and topography of the MCA. Our findings open new avenues for advancements in veterinary medicine and neuroscience research, with potential applications in the diagnosis and treatment of neurological disorders in dromedary camels. Furthermore, understanding the unique branching pattern of the MCA may have implications for comparative neuroanatomy and the evolution of cerebrovascular systems across species.

Complement Activation-Independent Attenuation of SARS-CoV-2 Infection by C1q and C4b-Binding Protein.

The complement system is a key component of the innate immune response to viruses and proinflammatory events. Exaggerated complement activation has been attributed to the induction of a cytokine storm in severe SARS-CoV-2 infection. However, there is also an argument for the protective role of complement proteins, given their local synthesis or activation at the site of viral infection. This study investigated the complement activation-independent role of C1q and C4b-binding protein (C4BP) against SARS-CoV-2 infection. The interactions of C1q, its recombinant globular heads, and C4BP with the SARS-CoV-2 spike and receptor binding domain (RBD) were examined using direct ELISA. In addition, RT-qPCR was used to evaluate the modulatory effect of these complement proteins on the SARS-CoV-2-mediated immune response. Cell binding and luciferase-based viral entry assays were utilised to assess the effects of C1q, its recombinant globular heads, and C4BP on SARS-CoV-2 cell entry. C1q and C4BP bound directly to SARS-CoV-2 pseudotype particles via the RBD domain of the spike protein. C1q via its globular heads and C4BP were found to reduce binding as well as viral transduction of SARS-CoV-2 spike protein expressing lentiviral pseudotypes into transfected A549 cells expressing human ACE2 and TMPRSS2. Furthermore, the treatment of the SARS-CoV-2 spike, envelope, nucleoprotein, and membrane protein expressing alphaviral pseudotypes with C1q, its recombinant globular heads, or C4BP triggered a reduction in mRNA levels of proinflammatory cytokines and chemokines such as IL-1ß, IL-8, IL-6, TNF-α, IFN-α, and RANTES (as well as NF-κB) in A549 cells expressing human ACE2 and TMPRSS2. In addition, C1q and C4BP treatment also reduced SARS-CoV-2 pseudotype infection-mediated NF-κB activation in A549 cells expressing human ACE2 and TMPRSS2. C1q and C4BP are synthesised primarily by hepatocytes; however, they are also produced by macrophages, and alveolar type II cells, respectively, locally at the pulmonary site. These findings support the notion that the locally produced C1q and C4BP can be protective against SARS-CoV-2 infection in a complement activation-independent manner, offering immune resistance by inhibiting virus binding to target host cells and attenuating the infection-associated inflammatory response.

Immune-Mediated Neuropathies: Pathophysiology and Management.

Dysfunction of the immune system can result in damage of the peripheral nervous system. The immunological mechanisms, which include macrophage infiltration, inflammation and proliferation of Schwann cells, result in variable degrees of demyelination and axonal degeneration. Aetiology is diverse and, in some cases, may be precipitated by infection. Various animal models have contributed and helped to elucidate the pathophysiological mechanisms in acute and chronic inflammatory polyradiculoneuropathies (Guillain-Barre Syndrome and chronic inflammatory demyelinating polyradiculoneuropathy, respectively). The presence of specific anti-glycoconjugate antibodies indicates an underlying process of molecular mimicry and sometimes assists in the classification of these disorders, which often merely supports the clinical diagnosis. Now, the electrophysiological presence of conduction blocks is another important factor in characterizing another subgroup of treatable motor neuropathies (multifocal motor neuropathy with conduction block), which is distinct from Lewis-Sumner syndrome (multifocal acquired demyelinating sensory and motor neuropathy) in its response to treatment modalities as well as electrophysiological features. Furthermore, paraneoplastic neuropathies are also immune-mediated and are the result of an immune reaction to tumour cells that express onconeural antigens and mimic molecules expressed on the surface of neurons. The detection of specific paraneoplastic antibodies often assists the clinician in the investigation of an underlying, sometimes specific, malignancy. This review aims to discuss the immunological and pathophysiological mechanisms that are thought to be crucial in the aetiology of dysimmune neuropathies as well as their individual electrophysiological characteristics, their laboratory features and existing treatment options. Here, we aim to present a balance of discussion from these diverse angles that may be helpful in categorizing disease and establishing prognosis.

Novel arthrocentesis approaches to the carpal joint of the Dromedary Camel (Camelus dromedarius).

The knowledge gap regarding the topography and anatomy of the dromedary's carpal joint must be bridged to improve diagnostic and treatment procedures such as ultrasonography, arthrocentesis, and arthroscopy. Thirty-five distal forelimbs were harvested from 21 dromedaries and studied through gross dissection, casting, ultrasonography, and computerized tomography. Representative three-dimensional models of the joint cavities, recesses, and pouches were obtained using various casting agents. The safety and feasibility of different arthrocentesis approaches were evaluated. This study provides a detailed description of dorsally located joint recesses and palmarly located joint pouches. The dorsomedial and dorsolateral approach is recommended for arthroscopy and arthrocentesis of the radiocarpal and intercarpal joint when the carpus is flexed. However, caution must be exercised during these approaches to prevent needle injury to the articulating cartilage. Caution is necessary to prevent the formation of inadvertent communication between the dorsally located tendon sheaths and joint cavities. Arthrocentesis via the lateral approach to the lateropalmar pouch is the most favourable approach for the radiocarpal joint. A subtendinous synovial bursa was found between the lateropalmar pouch of the radiocarpal joint and the extensor carpi ulnaris muscle. The subtendinous synovial bursa must be considered during the lateral arthrocentesis approach. The palmar approach is not recommended for arthrocentesis due to the high risk of injury to nerves, veins, and arteries located palmarly.

Vertebrobasilar Contribution to Cerebral Arterial System of Dromedary Camels (Camelus dromedarius).

It is hypothesized that in the "more highly evolved" mammals, including the domesticated mammals, that the brainstem and the cerebellum receive arterial blood through the vertebrobasilar system whilst the internal carotid arteries primarily supply the forebrain. In camels, the arterial blood supply to the brain differs from that of ruminants since the internal carotid artery and the rostral epidural rete mirabile (RERM) are both present and the basilar artery contributes a significant proportion of cerebral afferent blood. In this study, we described the anatomical distribution of the vertebrobasilar system arterial supply in the dromedary. Secondly, we determined the direction of blood flow within the vertebral and basilar arteries using transcranial color doppler ultrasonography. Thirdly, we quantified the percentage arterial contributions of the carotid and vertebrobasilar systems to the dromedary brain. Fifty-five heads of freshly slaughtered male Omani dromedaries aged 2-6 years were dissected to determine the distribution and topography of the arterial distribution to the brain. Their anatomical orientation was assessed by casting techniques using epoxy resin, polyurethane resin and latex neoprene. The epoxy resin and polyurethane resin casts of the head and neck arteries were used to measure the diameter of vertebrobasilar arterial system and carotid arterial system at pre-determined locations. These arterial diameters were used to calculate the percentage of blood supplied by each arterial system. The vertebrobasilar system in dromedary camels consists of paired vertebral arteries that contribute to the ventral spinal artery and basilar artery at multiple locations. In most specimens the vertebral artery was the primary contributor to the basilar artery compared to that of the ventral spinal artery. In four specimens the ventral spinal arteries appear to be the dominant contributor to the basilar artery. Transcranial color doppler ultrasonography confirmed that the direction of blood flow within the vertebral and basilar arteries was toward the brain in animals examined in ventral recumbency and when standing. The vertebrobasilar system contributes 34% of the blood supply to the brain. The vertebrobasilar system is the exclusive supply to the medulla oblongata, pons and cerebellum.

Measurement of the Femoral Anteversion Angle in Medium and Large Dog Breeds Using Computed Tomography.

To promote the development of an optimally functional total hip prosthesis for medium and large dog breeds, accurate measurements of the normal anatomy of the proximal femur and acetabular retroversion are essential. The aim of the current study was to obtain precise normal values of the femoral anteversion angle using computed tomography on cadavers of mature dogs with normal hip joints of both medium and large breeds. Based on the length of their femora 58 dogs were allocated either to group I: ≤195 mm or group II: >195 mm. In the study the femoral anteversion angle (FAA) was measured on each femur using multi-slice spiral computed tomography (CT). The data were processed as multi-planar and three-dimensional reconstructions using Advantage Workstation software. The CT measurements showed that the mean ± standard deviation (SD) FAA of group I was 31.34 ± 5.47° and in group II it was 31.02 ± 4.95°. There were no significant mean difference associations between the length of the femur and the femoral neck angle in either group (P > 0.05). The data suggest that a prosthesis FAA of 31 degrees would be suitable for a wide range of dog sizes.

Serological evidence of enzootic bovine leukosis in the periurban dairy cattle production system of Al Ain, United Arab Emirates.

The serostatus of enzootic bovine leukosis (EBL) was determined at three dairy farms and the Al Ain Livestock Market (AALM), within the Al Ain region of Abu Dhabi, UAE. Of the 957 bovine sera tested by ELISA, 657 were from Holstein-Friesians from three dairy farms, and 300 from Bos indicus cattle at AALM. The chi-square homogeneity test (CSHT) and the Marascuilo multiple comparison procedure (MMCP) assessed the level of significance between the proportions of EBL-seropositive cattle (ESPC) across the study farms and AALM, and between the age groups at farms 1 and 3. Overall, the proportion of ESPC was 25.7% at dairy farms and AALM, 37.0% for farms and 1.0% for AALM. Furthermore, the proportions of ESPC at farms 1, 2 and 3 were 54.7%, 0.0% and 26.3% respectively, and statistically significant differences were seen across the farm/farm and farm/AALM comparisons, and between two age groups at farms 1 and 3. The 37-72-month-old age group showed the highest proportion of ESPC. This is the first serological evidence of EBL in the UAE. As previously reported, the ESPC are comparatively higher in dairy than Bos indicus cattle. Molecular and more extensive serological studies are needed to further corroborate the present data. Meanwhile, the UAE veterinary authorities will need to formulate national EBL control policies.

Descriptive Analysis of Cerebral Arterial Vascular Architecture in Dromedary Camel (Camelus dromedarius).

The artiodactyl brain has multiple levels of vascular pooling and the rostral epidural rete mirabile (RERM) at its base. The current study is the first of its kind to precisely demonstrate the arterial vasculature of the dromedary brain, utilizing a new casting method with colored latex and epoxy paint. In total, 35 freshly slaughtered dromedary heads were injected with colored latex or colored epoxy paint prior to dissection in order to reveal cerebral vasculature; Ten processed heads were chemically digested with 5% potassium hydroxide to obtain hard casts of cerebral arteries and anastomosing structures. The outcomes of this study ascertain the distinct vascular features of dromedaries that set them apart from other artiodactyls. In addition to the RERM, the dromedary possesses a well-developed ophthalmic and chiasmatic rete. The dromedary is similar to giraffe, goat, cat and pig in the contribution of middle meningeal artery to the rete mirabile; however, dromedaries have several arteries emerging directly from the cerebral arterial circle that supply the choroid plexus and pineal gland. Additionally, dromedaries exhibit a dominant basilar system that dominates the blood supply to the medulla oblongata, pons, and cerebellum. In our study, we were able to graphically prove the lack of connection between the areas supplied by vertebrobasilar system and carotid system in the dromedary. Furthermore, the vertebral artery does not branch into the basilar artery; instead, it acts as a contributing vessel to the ventral spinal artery that later fuse to form the basilar artery. This study employed the new casting method to illustrate a new arterial source to RERM and the various anastomoses among arterial sources supplying the brain in the dromedary. These anastomoses play an important role in maintaining an uninterrupted cerebral blood supply, decreasing the vulnerability of the fragile brain against ischemia and stroke, as well as, play an important role in maintaining blood pressure and flow in long-necked dromedaries when they raise or lower their heads.

Measurement of the femoral neck angle in medium and large dog breeds using computed tomography.

The aim of this study was to get precise normal values of the femoral neck angle (FNA) in support of developing an optimally functioning total hip prosthesis for medium and large dog breeds. Accordingly, two- and three-dimensional computed tomographic images of the anatomical structures of the proximal femora of 58, hip-dysplasia-free, mature dogs of medium and large breeds were studied. Based on the length of their femora the dogs were allocated to Group I (from 145 to 195 mm) and Group II (from 196 to 240 mm). The FNA was measured on each femur using multi-slice spiral computed tomography (CT). The two- and three-dimensional image data were processed as multi-planar and threedimensional reconstructions using Advantage Workstation software. The CT measurements revealed that Group I had an average femoral neck angle of 147.59° (min. 144.05°, max. 153.35°), while in Group II the average FNA was 147.46° (min. 141°, max. 154.35°). There was no significant correlation between the length of the femur and the FNA in either group. The optimal FNA for a total hip prosthesis is 147.5° for medium and large dog breeds.

Radial and ulnar fracture treatment with paraosseous clamp-cerclage stabilisation technique in 17 toy breed dogs.

OBJECTIVE: Description of surgical technique, complications and outcome of radius/ulna fractures in toy and miniature breed dogs treated with the paraosseous clamp-cerclage stabilisation (PCCS) method. STUDY DESIGN: Retrospective study. METHODS: Clinical records of small breed dogs with fractures of the radius and ulna were reviewed between January 2011 and January 2016. Inclusion criteria were bodyweight of ≤3.5 kg, fracture of the radius and ulna of one or two limbs without previous repair attempts, available follow-up information, and the use of PCCS for repair of the fracture as the sole method of fixation. RESULTS: Seventeen fractures in 17 dogs were included in the study. Radiographic union was documented in 13/17 cases. Median time to radiographic union was 13 weeks (range: 5-53 weeks). Major complications occurred in 24 per cent (4/17) due to implant failure, and for revision surgery the PCCS method was chosen in all four cases. Three of four revised fractures healed radiographically. One of the four dogs was lost for radiographic follow-up, but the owner could be contacted for a telephone questionnaire. Eleven of 17 dogs achieved an excellent return to function without any lameness during clinical examination, but 5/17 dogs showed an intermittent mild lameness despite full radiographic union. Routine implant removal was performed in 9/17 dogs. The owners of 15/17 dogs could be contacted for a telephone questionnaire for a long-term follow-up. No further complications were reported. CONCLUSIONS: PCCS is a feasible low-cost internal fixation technique for repairing radial and ulnar fractures in toy breed dogs. Further biomechanical and clinical studies are needed for better evaluation of the PCCS method.

Diagnosis and surgical correction of congenital bilateral patellar luxation in two dwarf zebu calves.

This case study presents two female dwarf zebu calves with permanent bilateral flexion of the stifle joint secondary to bilateral congenital lateral patellar luxation. The patella could be manually repositioned bilaterally in the first calf (14 days old), but re-luxated immediately with release of manual pressure (luxation grade III). In the second calf (28 days old) both patellae were permanently luxated laterally (grade IV). The right and left stifles of each calf were operated in a staged procedure with approximately 14 days between surgery of the two sides. While a lateral release and a medial imbrication were sufficient for correction in the left stifle of the younger calf, a trochlear wedge resection was required in the other three stifle joints with hypo- to aplastic trochleas in order to stabilize the patella. Postoperatively each stifle was immobilized for 10 days with a cast. The younger calf regained full function of the hind limbs during the complete gait cycle in walk and in trot one month after the procedure. The older calf regained full function in the hind limbs in walk but in trot there was some degree of lameness due to a reduced extension of approximately 20°.

Larynx Trauma and Hyoid Bone Fracture after Bite Injury in Dog: Case Report.

An 8-year-old male Jack Russell crossbreed dog was admitted to our hospital with dyspnea and shock following a dog-bite injury on the ventral neck. Radiographs revealed subcutaneous emphysema and bilateral thyrohyoid bone fractures. Intraoperatively, rupture of both sternohyoid muscles, both hyoepiglotticus muscles, both thyrohyoid muscles, and a partial cranial rupture of the superficial sphincter colli muscle were detected. Part of the epiglottis was detached from the thyroid cartilage. The patient's severed muscles and torn epiglottis were reattached using a simple interrupted suture pattern. Hyoepiglotticus muscles could not be identified. The bilateral thyrohyoid bone fractures were repaired with intraosseous wire suture. A temporary tracheostomy tube and an esophageal feeding tube were placed postoperatively. The dog was discharged after 8 days, re-examined at 2 and 6 months and laryngeal and pharyngeal function were evaluated as normal. To the authors' knowledge, this is the first report of a dog that presented with laryngeal trauma with hyoid bone fracture and acute dyspnea that underwent surgical treatment resulting in an acceptable outcome.