The ultrastructure of peroxisomes in the kidney of the camel (Camelus dromedarius).

Dromedary camels can survive and reproduce in desert areas. The unique anatomical structure of the kidney enables the camel to prevent water loss. The present study aimed to investigate the ultrastructure of the peroxisomes in the normal kidney of the adult dromedary camel. Tissue samples were taken from the cortex and outer medulla of the kidney of eight camels. The samples were then processed for histological and ultrastructural investigations. The epithelial cells of the proximal tubules displayed peroxisomes with varying sizes and shapes. The peroxisomes were observed in either dispersed or clustered arrangement. Each peroxisome exhibited a homogenous matrix enveloped by a single membrane. Several peroxisomes exhibited one or more dark marginal plates that were always strongly associated with the smooth endoplasmic reticulum. The intensity of the peroxisomal matrix differed significantly, either within the same cell or across different cells. The intensity was light or dark, with a few peroxisomes presenting a similar intensity to that of the mitochondria. Some peroxisomes contained nucleoids within their matrix. The peroxisomes in the first and second sections of proximal convoluted tubules were scattered and primarily located in the region between the microvilli and the underlying mitochondria. The peroxisomes in the third region were abundant and frequently aggregated in clusters throughout the cytoplasm. In the fourth region, the number of peroxisomes was low. The proximal straight tubule had a limited quantity of peroxisomes. In conclusion, peroxisomes in the proximal tubule in kidney of normal dromedary camel were similar in shape and size to other mammals; however, heterogeneity exists as a result of differences in species-specific peroxisomal proteins. Peroxisomes are suggested to be a major source of metabolic energy and act as hydrogen peroxide (H2O2) scavengers, resulting in the release of water and oxygen.

Effects of long-term dehydration and quick rehydration on the camel kidney: pathological changes and modulation of the expression of solute carrier proteins and aquaporins.

BACKGROUND: Recurrent dehydration causes chronic kidney disease in humans and animal models. The dromedary camel kidney has remarkable capacity to preserve water and solute during long-term dehydration. In this study, we investigated the effects of dehydration and subsequent rehydration in the camel's kidney histology/ultrastructure and changes in aquaporin/solute carrier proteins along with gene expression. RESULTS: In light microscopy, dehydration induced few degenerative and necrotic changes in cells of the cortical tubules with unapparent or little effect on medullary cells. The ultrastructural changes encountered in the cortex were infrequent during dehydration and included nuclear chromatin condensation, cytoplasmic vacuolization, mitochondrial swelling, endoplasmic reticulum/ lysosomal degeneration and sometimes cell death. Some mRNA gene expressions involved in cell stability were upregulated by dehydration. Lesions in endothelial capillaries, glomerular membranes and podocyte tertiary processes in dehydrated camels indicated disruption of glomerular filtration barrier which were mostly corrected by rehydration. The changes in proximal tubules brush borders after dehydration, were accompanied by down regulation of ATP1A1 mRNA involved in Na + /K + pump that were corrected by rehydration. The increased serum Na, osmolality and vasopressin were paralleled by modulation in expression level for corresponding SLC genes with net Na retention in cortex which were corrected by rehydration. Medullary collecting ducts and interstitial connective tissue were mostly unaffected during dehydration. CKD, a chronic nephropathy induced by recurrent dehydration in human and animal models and characterized by interstitial fibrosis and glomerular sclerosis, were not observed in the dehydrated/rehydrated camel kidneys. The initiating factors, endogenous fructose, AVP/AVPR2 and uric acid levels were not much affected. TGF-ß1 protein and TGF-ß1gene expression showed no changes by dehydration in cortex/medulla to mediate fibrosis. KCNN4 gene expression level was hardly detected in the dehydrated camel's kidney; to encode for Ca + + -gated KCa3.1 channel for Ca + + influx to instigate TGF-ß1. Modulation of AQP 1, 2, 3, 4, 9 and SLC protein and/or mRNAs expression levels during dehydration/rehydration was reported. CONCLUSIONS: Long-term dehydration induces reversible or irreversible ultrastructural changes in kidney cortex with minor effects in medulla. Modulation of AQP channels, SLC and their mRNAs expression levels during dehydration/rehydration have a role in water conservation. Cortex and medulla respond differently to dehydration/rehydration.

Seroprevalence and molecular detection of Brucella infection in livestock in the United Arab Emirates.

Small ruminants and camels are important livestock species in the United Arab Emirates (UAE), although Brucella infection can limit their productivity. This study aimed to investigate the seroprevalence of Brucella infection and its associated risk factors in small ruminants and camels in the Emirate of Abu Dhabi. Additionally, seropositive animals were tested for the DNA of Brucella. Multispecies competitive enzyme-linked immunosorbent assay (c-ELISA) and multispecies indirect (i-ELISA) were used to test 3,086 animals from 2022 to 2023. Brucella cell surface 31 kDa protein (bcsp31) gene-based real-time polymerase chain reaction (q-PCR) was used to detect Brucella DNA. Multivariate logistic regression was used to assess the association between seroprevalence and potential risk factors. The overall seroprevalences of Brucella infection were 1.7% (95% confidence interval [CI], 1.2%-2.2%) and 5.8% (95% CI, 5.0%-6.7%) based on serial and parallel testing, respectively. The DNA of Brucella was detected in 13 of the 51 seropositive animals. The overall seroprevalence of Brucella infection was associated with the region, type of animal holding, species, and age of the animals. In conclusion, this study documented Brucella infection in small ruminants and camels in the Emirate of Abu Dhabi, warranting necessary intervention strategies to eliminate Brucella infections in livestock populations.

Mathematical assessment of control strategies against the spread of MERS-CoV in humans and camels in Saudi Arabia.

A new mathematical model for the transmission dynamics and control of the Middle Eastern respiratory syndrome (MERS), a respiratory virus caused by MERS-CoV coronavirus (and primarily spread to humans by dromedary camels) that first emerged out of the Kingdom of Saudi Arabia (KSA) in 2012, was designed and used to study the transmission dynamics of the disease in a human-camel population within the KSA. Rigorous analysis of the model, which was fitted and cross-validated using the observed MERS-CoV data for the KSA, showed that its disease-free equilibrium was locally asymptotically stable whenever its reproduction number (denoted by $ {\mathbb R}_{0M} $) was less than unity. Using the fixed and estimated parameters of the model, the value of $ {\mathbb R}_{0M} $ for the KSA was estimated to be 0.84, suggesting that the prospects for MERS-CoV elimination are highly promising. The model was extended to allow for the assessment of public health intervention strategies, notably the potential use of vaccines for both humans and camels and the use of face masks by humans in public or when in close proximity with camels. Simulations of the extended model showed that the use of the face mask by humans who come in close proximity with camels, as a sole public health intervention strategy, significantly reduced human-to-camel and camel-to-human transmission of the disease, and this reduction depends on the efficacy and coverage of the mask type used in the community. For instance, if surgical masks are prioritized, the disease can be eliminated in both the human and camel population if at least 45% of individuals who have close contact with camels wear them consistently. The simulations further showed that while vaccinating humans as a sole intervention strategy only had marginal impact in reducing the disease burden in the human population, an intervention strategy based on vaccinating camels only resulted in a significant reduction in the disease burden in camels (and, consequently, in humans as well). Thus, this study suggests that attention should be focused on effectively combating the disease in the camel population, rather than in the human population. Furthermore, the extended model was used to simulate a hybrid strategy, which combined vaccination of both humans and camels as well as the use of face masks by humans. This simulation showed a marked reduction of the disease burden in both humans and camels, with an increasing effectiveness level of this intervention, in comparison to the baseline scenario or any of the aforementioned sole vaccination scenarios. In summary, this study showed that the prospect of the elimination of MERS-CoV-2 in the Kingdom of Saudi Arabia is promising using pharmaceutical (vaccination) and nonpharmaceutical (mask) intervention strategies, implemented in isolation or (preferably) in combination, that are focused on reducing the disease burden in the camel population.

Circulation of Non-Middle East Respiratory Syndrome (MERS) Coronaviruses in Imported Camels in Saudi Arabia.

Background Coronaviruses (CoVs) pose significant health risks to humans, with recent outbreaks like severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) underscoring their zoonotic potential. Dromedary camels (Camelus dromedarius) have been implicated as intermediate hosts for MERS-CoV, prompting heightened surveillance efforts. This study aims to identify non-MERS-CoV CoVs in imported camels at the Jeddah seaport, Saudi Arabia, using molecular techniques. Methods Camel nasal swabs (n = 337) were collected from imported dromedary camels arriving at the Jeddah Islamic seaport from Sudan and Djibouti. Samples were tested for CoVs using real-time real-time reverse transcription polymerase chain reaction (RT-PCR) targeting the RNA-dependent RNA polymerase gene. Positive samples were confirmed by conventional RT-PCR and Sanger sequencing. Selected samples underwent RNA sequencing to identify viral genomes. The study underscores the importance of molecular surveillance in camels to mitigate zoonotic risks. Results Out of 337 camel samples tested, 28 (8.30%) were positive for CoVs, predominantly from camels imported from Djibouti, compared to Sudan (13.39% vs. 5.78%). Sequence analysis confirmed the presence of non-MERS CoVs, including camel alpha-coronavirus and human CoV-229E-related strains. These findings highlight potential viral diversity and transmission risks in imported camel populations. Conclusion This study identifies diverse CoVs circulating in imported dromedary camels at the Jeddah Islamic seaport, Saudi Arabia, underscoring their potential role in zoonotic transmission. Enhanced surveillance and collaborative efforts are essential to mitigate public health risks associated with novel coronavirus strains from camel populations.

Molecular identification and morphological variations of Amblyomma lepidum imported to Egypt, with notes about its potential distribution under climate change.

The tick Amblyomma lepidum is an ectoparasite of veterinary importance due to its role in transmitting livestock diseases in Africa, including heartwater. This study was conducted in 2023 to monitor Amblyomma spp. infestation in dromedary camels imported from Somalia, Ethiopia, and Sudan to Egypt. This study inspected 200 camels at the Giza governorate's camel market that had been imported from Somalia, 200 from Ethiopia, and 200 from Sudan for tick infestation. Specimens were identified using morphological characteristics and phylogenetic analyses of the 12S and 16S rRNA genes. Clusters were calculated using an unweighted pair-group method with arithmetic averages (UPGMA) dendrogram to group the specimens according to their morphometric characteristics. The morphometric analysis compared the body shape of ticks collected from different countries by analyzing dorsal features. Principal component analysis (PCA) and canonical variate analysis (CVA) were performed to obtain body shape variation among specimens from different countries. Results indicated that camels were infested by 57 males Amblyomma lepidum, and no female specimens were observed; among these specimens, one may have a morphological abnormality. The results suggest that A. lepidum specimens collected from camels imported to Egypt from African countries exhibit locally adapted morphology with variations among specimens, particularly variations in body size. This adaptation suggests minimal potential for genetic divergence. Ecological niche modeling was used to predict the areas in Africa with suitable climates for A. lepidum. The study confirmed that East African countries might have the most favorable climatic conditions for A. lepidum to thrive. Interestingly, the amount of rain during the wettest quarter (Bio16) had the strongest influence on the tick's potential distribution, with suitability decreasing sharply as rainfall increased. Future predictions indicate that the climatic habitat suitability for A. lepidum will decrease under changing climate conditions. However, historical, current, and future predictions indicate no suitable climatic habitats for A. lepidum in Egypt. These findings demand continuous surveillance of A. lepidum in camel populations and the development of targeted strategies to manage tick infestations and prevent the spread of heartwater disease.

Fetal gender prediction by monitoring circulating steroid hormones and some biochemical parameters in maternal dromedary camels.

To predict the sex of the foetus, healthy pregnant dromedary camels (n = 24) were included. Blood samples were collected for measurements of progesterone, estradiol, testosterone, and cortisol as well as total proteins, albumin, glucose, creatinine, blood urea nitrogen, phosphorus, calcium, creatine kinase, alanine aminotransferase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), gamma glutamyl transpeptidase (GGT), calcium, phosphorus, and magnesium. Statistical analysis revealed differences between pregnant camels and pregnant camels in terms of female or male foetuses depending on the actual sex of the born calf. The results revealed that testosterone and ALP concentrations were significantly (P < 0.001) greater in camels given to males than in those given to calves. There were strong positive correlations between male calf birth and testosterone and ALP concentrations (r = 0.864; P < 0.0001 and r = 0.637; P < 0.001, respectively). On the other hand, the cortisol, glucose and creatinine concentrations were significantly lower (P lower in camel calved males than in females). There were significant negative correlations between male calf birth and the cortisol, glucose and creatinine concentrations (r =-0.401; P = 0.052; r =-0.445; P = 0.029 and r =-0.400; P = 0.053, respectively). The concentrations of calcium, phosphorus, calcium/phosphorus ratio, magnesium, and albumin and the albumin/globulin ratio were not significantly different (P > 0.05) between the two groups. In conclusion, testosterone could be used as a biomarker to determine the sex of foetuses in dromedary camels.

Tissue-specific localization of tick-borne pathogens in ticks collected from camels in Kenya: insights into vector competence.

Background: Tick-borne pathogen (TBP) surveillance studies often use whole-tick homogenates when inferring tick-pathogen associations. However, localized TBP infections within tick tissues (saliva, hemolymph, salivary glands, and midgut) can inform pathogen transmission mechanisms and are key to disentangling pathogen detection from vector competence. Methods: We screened 278 camel blood samples and 504 tick tissue samples derived from 126 camel ticks sampled in two Kenyan counties (Laikipia and Marsabit) for Anaplasma, Ehrlichia, Coxiella, Rickettsia, Theileria, and Babesia by PCR-HRM analysis. Results: Candidatus Anaplasma camelii infections were common in camels (91%), but absent in all samples from Rhipicephalus pulchellus, Amblyomma gemma, Hyalomma dromedarii, and Hyalomma rufipes ticks. We detected Ehrlichia ruminantium in all tissues of the four tick species, but Rickettsia aeschlimannii was only found in Hy. rufipes (all tissues). Rickettsia africae was highest in Am. gemma (62.5%), mainly in the hemolymph (45%) and less frequently in the midgut (27.5%) and lowest in Rh. pulchellus (29.4%), where midgut and hemolymph detection rates were 17.6% and 11.8%, respectively. Similarly, in Hy. dromedarii, R. africae was mainly detected in the midgut (41.7%) but was absent in the hemolymph. Rickettsia africae was not detected in Hy. rufipes. No Coxiella, Theileria, or Babesia spp. were detected in this study. Conclusions: The tissue-specific localization of R. africae, found mainly in the hemolymph of Am. gemma, is congruent with the role of this tick species as its transmission vector. Thus, occurrence of TBPs in the hemolymph could serve as a predictor of vector competence of TBP transmission, especially in comparison to detection rates in the midgut, from which they must cross tissue barriers to effectively replicate and disseminate across tick tissues. Further studies should focus on exploring the distribution of TBPs within tick tissues to enhance knowledge of TBP epidemiology and to distinguish competent vectors from dead-end hosts.

Epidemiology and Scenario Simulations of the Middle East Respiratory Syndrome Corona Virus (MERS-CoV) Disease Spread and Control for Dromedary Camels in United Arab Emirates (UAE).

Middle East Respiratory Syndrome (MERS-CoV) is a coronavirus-caused viral respiratory infection initially detected in Saudi Arabia in 2012. In UAE, high seroprevalence (97.1) of MERS-CoV in camels was reported in several Emirate of Abu Dhabi studies, including camels in zoos, public escorts, and slaughterhouses. The objectives of this research include simulation of MERS-CoV spread using a customized animal disease spread model (i.e., customized stochastic model for the UAE; analyzing the MERS-CoV spread and prevalence based on camels age groups and identifying the optimum control MERS-CoV strategy. This study found that controlling animal mobility is the best management technique for minimizing epidemic length and the number of affected farms. This study also found that disease dissemination differs amongst camels of three ages: camel kids under the age of one, young camels aged one to four, and adult camels aged four and up; because of their immunological state, kids, as well as adults, had greater infection rates. To save immunization costs, it is advised that certain age groups be targeted and that intense ad hoc unexpected vaccinations be avoided. According to the study, choosing the best technique must consider both efficacy and cost.

Serological and molecular survey of brucellosis and chlamydiosis in dromedary camels from Tunisia.

The present sero-epidemiological survey was designed and conducted to scrutinize the current status of camel-related brucellosis and chlamydiosis in Tunisia. Whole blood and serum samples were collected from 470 dromedaries (Camelus dromedarius) from eight different Tunisian governorates. Serum samples were subjected to indirect enzyme-linked immunosorbent assay (iELISA). The detection of Brucella and Chlamydia DNA was performed using conventional PCR targeting the bcsp-31 and 16 S rRNA gene, respectively. Overall, 10/470(2.12%) and 27/470 (5.75%) camels were revealed seropositive to Brucella and Chlamydia, respectively. Multivariate logistic regression analysis showed different risk factors associated with these infections. Meaningful high rates of seropositivity of brucellosis (9.5%; p = 0.000; OR=64.193) and chlamydiosis (22.6%; p = 0.000; OR=42.860) were noted among camels showing previous abortions in particular for aged females. Besides, Chlamydia seropositivity is significantly important during winter (12.5%; p = 0.009; OR= 27.533), and in camels raised in small farms (11.4%, p = 0.000, OR=86.052). Molecular analysis revealed no positivity from all analyzed blood samples. These findings indicate the involvement of camels in the epidemiology of these abortive infectious diseases. This raises awareness and serious public health concern for infectious camel diseases in order to develop further diagnostic improvements and effective control strategies.

Assessing genetic diversity and defining signatures of positive selection on the genome of dromedary camels from the southeast of the Arabian Peninsula.

Dromedary camels (Camelus dromedarius) are members of the Camelini tribe within the Camelidae family. They are distributed throughout North Africa, the Arabian Peninsula and Southeast Asia. This domestic species is characterized by its superior adaptability to the harsh desert environment. In this study, whole autosomal data of 29 dromedary samples from the Southeast Arabian Peninsula in Oman; 10 from Muscat, 14 from Al-Batinah, and 5 from Al-Sharqiya, were investigated to assess their genetic relationship and to define candidate signatures of positive selection. A minimal genetic distinction that separates Muscat dromedaries from the other two populations was observed, with a degree of genetic admixture between them. Using the de-correlated composite of multiple signals (DCMS) approach, a total of 47 candidate regions within the autosomes of these dromedary populations were defined with signatures of positive selection. These candidate regions harbor a total of 154 genes that are mainly associated with functional categories related to immune response, lipid metabolism and energy expenditure, optical and auditory functions, and long-term memory. Different functional genomic variants were called on the candidate regions and respective genes that warrant further investigation to find possible association with the different favorable phenotypes in dromedaries. The output of this study paves the way for further research efforts aimed at defining markers for use in genomic breeding programs, with the goal of conserving the genetic diversity of the species and enhancing its productivity.

Crimean-Congo Hemorrhagic Fever Virus Seropositivity among Dromedary Camels, Algeria, 2020-2021.

Serosurvey results for Crimean-Congo hemorrhagic fever virus antibodies in dromedary camels in Algeria indicate that the pathogen is circulating endemically in desertic areas, despite the hostile environment. Thus, dromedaries are suitable sentinels for detecting human risk for Crimean-Congo hemorrhagic fever in desertic areas.

First serological and molecular investigation of hepatitis E virus infection in dromedary camels in Algeria.

Hepatitis E is an acute self-limited or fulminant infection in humans, caused by the hepatitis E virus (HEV). This member of the Hepeviridae family has been identified in a wide range of domestic and wild animals all over the world, with a possible transmission to humans through fecal oral route, direct contact and ingestion of contaminated meat products, making it one of the global zoonotic and public health major concerns. Since there is no monitoring program and a lack of data on HEV in animals in Algeria, the current preliminary survey has been undertaken to elucidate the exposure to the virus in camels at abattoirs of six southern provinces of Algeria. Two-hundred and eight sera/plasma were collected and analyzed (by double antigen sandwich ELISA) for the presence of total anti-HEV antibodies, among which 35.1% were positive, but no HEV RNA could be isolated from them (by two pan-HEV nested RT-PCR and broad range real-time reverse transcription RT-PCR). The univariate analysis showed significant associations (p < 0.05) between HEV seroprevalence and province of origin, age, and sex of camels, whereas the multivariable logistic regression analysis revealed a negative impact of camels' age on it. The obtained results confirm that HEV infection is widespread established in the camelid population of Algeria.

Molecular screening of Amblyomma species (Acari: Ixodidae) imported from African countries to Egypt, with the first report of Amblyomma latum from the ball python, Python regius (Squamata: Pythonidae).

Amblyomma species are non-endemic ticks in Egypt, which have been recorded from imported animals. This study was carried out in 2022 to monitor Amblyomma spp. from dromedary camels, cattle, and snakes in Egypt. During this study, 400 camels, 200 cattle, and two snakes (Pythonidae) were inspected for tick infestation. Collected specimens were identified based on morphological characters and confirmed by phylogenetic analysis of the 12S rRNA gene. Camels were infested by adult specimens of Amblyomma variegatum and Amblyomma lepidum, but no Amblyomma spp. were collected from cattle. Amblyomma variegatum showed high genetic similarity to other A. variegatum from Guinea-Bissau and São Tomé (> 99.99%), and A. lepidum showed high genetic similarity to other A. lepidum from Israel and Sudan (99.99%). Amblyomma latum is recorded in Egypt from the ball python snake for the first time and showed high genetic similarity with South African A. latum (99.87%).

A comparison of culture and cooling for the short term preservation of in vivo derived dromedary camel embryos of varying morphological quality.

Despite recent advancements in the cryopreservation of dromedary camel embryos, widespread application of the technique is still limited by the need for specialised vitrification equipment and supplies. Temporary, liquid-phase embryo storage methods provide a useful tool for short-term preservation of camel embryos. In the current study, we compared the use of in vitro embryo culture with cold liquid storage in order to maintain both high- (Grade 1- Excellent and 2-Good) and low- (Grade 3- Moderate and 4-Poor) morphological grade Day-7 dromedary camel embryos in vitro for up to 3 days. Embryos were either cooled and placed in Hams-F10 medium supplemented with HEPES and 10% FBS and then kept at 4 °C; or placed in Hams-F10 supplemented with sodium bicarbonate and 10% FBS and then cultured in a humidified atmosphere of 6% CO2 at 37 °C before being assessed for viability at 24 h. In high-morphological grade embryos, both cold storage and culture supported 100% viability (maintenance of normal morphology) over this period (Cooled n = 22, Cultured n = 20). In low-morphological grade embryos, culture supported higher viability (16/18, 88.9%) than did cooling (4/18, 22.2%). We then evaluated the effect of up to 3 days of cold storage or culture on embryo morphological grade, diameter, and developmental competence following embryo transfer. High-grade embryos were divided between culture and cold storage; low-grade embryos were evaluated only after culture. Over 3 days of culture, both high- and low-grade embryos tended to either maintain or improve upon their initial morphological score (P < 0.05) and increased in diameter (P < 0.001). Embryos subjected to cooling tended to have reduced morphological scores by 48 h of storage and decreased in diameter by 72 h (P < 0.05). No significant influence of storage method (cooling vs. culture), duration (24-72 h), or embryo grade (high vs low) was observed on pregnancy establishment at Day-60 (22.2%-57.2% pregnancy rates for all treatments). Overall, rates of pregnancy establishment were similar for transferred cultured (n = 45) and cooled (n = 45) embryos (pregnancy rates at Day 18, 48% vs 51.1%; at Day 60, 37.7% vs 37.7%). Rates of embryonic loss also were similar (22.7% vs 26%). In conclusion, whilst similar rates of pregnancy and pregnancy loss were observed following the transfer of both cooled and cultured embryos held in vitro for up to 3 days, amongst the two methods, only embryo culture appears to provide a means of effectively preserving Day- 7 dromedary camel embryos with reduced morphological values in vitro. Considering these embryos appear to show poor tolerance to the cooling procedure and are unlikely candidates for vitrification, embryo culture may provide an effective method for deriving pregnancies from low-morphological grade embryos when immediate transfer is not possible on the day of flushing.

MERS-CoV‒Specific T-Cell Responses in Camels after Single MVA-MERS-S Vaccination.

We developed an ELISPOT assay for evaluating Middle East respiratory syndrome coronavirus (MERS-CoV)‒specific T-cell responses in dromedary camels. After single modified vaccinia virus Ankara-MERS-S vaccination, seropositive camels showed increased levels of MERS-CoV‒specific T cells and antibodies, indicating suitability of camel vaccinations in disease-endemic areas as a promising approach to control infection.

Prevalence and Molecular Characterization of Methicillin-Resistant Staphylococci (MRS) and Mammaliicocci (MRM) in Dromedary Camels from Algeria: First Detection of SCCmec-mecC Hybrid in Methicillin-Resistant Mammaliicoccus lentus.

Dromedary camels are an important source of food and income in many countries. However, it has been largely overlooked that they can also transmit antibiotic-resistant bacteria. The aim of this study was to identify the Staphylococcaceae bacteria composition of the nasal flora in dromedary camels and evaluate the presence of methicillin-resistant Mammaliicoccus (MRM) and methicillin-resistant Staphylococcus (MRS) in dromedary camels in Algeria. Nasal swabs were collected from 46 camels from seven farms located in two different regions of Algeria (M'sila and Ouargla). We used non-selective media to determine the nasal flora, and antibiotic-supplemented media to isolate MRS and MRM. The staphylococcal isolates were identified using an Autoflex Biotyper Mass Spectrometer (MALDI-TOF MS). The mecA and mecC genes were detected by PCR. Methicillin-resistant strains were further analysed by long-read whole genome sequencing (WGS). Thirteen known Staphylococcus and Mammaliicoccus species were identified in the nasal flora, of which half (49.2%) were coagulase-positive staphylococci. The results showed that four out of seven farms were positive for MRS and/or MRM, with a total of 16 isolates from 13 dromedary camels. The predominant species were M. lentus, S. epidermidis, and S. aureus. Three methicillin-resistant S. aureus (MRSA) were found to be ST6 and spa type t304. Among methicillin-resistant S. epidermidis (MRSE), ST61 was the predominant ST identified. Phylogenetic analysis showed clonal relatedness among M. lentus strains, while S. epidermidis strains were not closely related. Resistance genes were detected, including mecA, mecC, ermB, tet(K), and blaZ. An SCCmec type VIII element was found in a methicillin-resistant S. hominis (MRSH) belonging to the ST1 strain. An SCCmec-mecC hybrid element was detected in M. lentus, similar to what was previously detected in M. sciuri. This study highlights that dromedary camels may be a reservoir for MRS and MRM, and that they contain a specific set of SCCmec elements. This emphasizes the need for further research in this ecological niche from a One Health perspective.

Phenotypic biodiversity characterization of dromedary camels and hybrids in Kazakhstan.

Kazakhstan is one of the rare camel countries with rich camel biodiversity where different dromedary camels, Bactrian camels, and hybrid types are cohabiting at the same territories during centuries. Several data on phenotype biodiversity of local camels are available, mostly published during Soviet Union time using few body quantitative measurements. Unfortunately, those data are not sufficient to place the local breeds among the world camel population. The aim of this study was to describe detailed phenotype parameters of dromedary camels and hybrids in Kazakhstan and to compare our animals with the other camel populations in the world. As the whole, six camel farms were visited, located in different regions of southern Kazakhstan. In total, 185 female camels (Aruana breed camels and hybrids) were described by the phenotype questionnaire. There was a significant effect of "breed" on the different parameters except udder depth and body length. Most of the measurements were lower in Aruana compared to hybrids. The discriminating factorial analysis confirmed the clear separation between the breed based on their body measurements with a total of 95% of well-classed. The main discriminating parameters (allowing distinguishing the populations) were in the order: (i) the length of the head, (ii) the neck length, (iii) the neck circumference, (iv) the teat length, and (v) the udder length.

First report on the isolation of Chlamydia abortus from female dromedary camels with ovarian hydrobursitis.

This study sought to isolate Chlamydia abortus (C. abortus) from camels with ovarian hydrobursitis (OVHB). To accomplish this goal, bursal tissue (n = 5) and bursal fluid (n = 6) samples were collected from 11 female dromedary camels with unilateral OVHB. A quantitative polymerase chain reaction (qPCR) was used for the preliminary detection of C. abortus in the infected samples. For the purpose of isolation, the prepared samples were inoculated into embryonated chicken eggs. Giemsa, Gimenez, and direct immunofluorescence (DIF) staining were used to detect any chlamydial inclusions in the infected yolk sacs. A second qPCR was then performed on the infected yolk sacs. The C. abortus gene was detected in 83.8% of the infected bursal tissue and bursal fluid samples. All the yolk sac smears treated with Giemsa, Gimenez, and DIF staining revealed intracytoplasmic inclusion bodies. Moreover, hemorrhagic patches, massive congestion, macerated yolk sacs, and dwarfism were observed in the infected chicken embryos. The C. abortus gene was also found in 63.6% of the infected yolk sacs. In conclusion, this is the first report of C. abortus isolation from female dromedary camels with OVHB, which represents a key step toward developing a practical vaccine and avoiding fertility problems in female camels.

Seroprevalence and Molecular Evidence of Coxiella burnetii in Dromedary Camels of Pakistan.

Coxiellosis is a zoonosis in animals caused by Coxiella burnetii. A cross-sectional study was conducted on 920 (591 female and 329 male) randomly selected camels (Camelus dromedarius) of different age groups from 13 districts representative of the three different ecological zones in the Province Punjab, Pakistan to determine the prevalence and associated risk factors of coxiellosis. The blood samples were collected and tested for anti-C. burnetti antibodies using indirect multispecies ELISA. Real-time PCR was used for the detection of C. burnetii DNA to determine the prevalence in heparinized blood pools. Out of 920 investigated camels, anti-C. burnetii antibodies were detected in 288 samples (31.3%) (95% CI: 28.3-34.4%). The highest (78.6%) and lowest (1.8%) seroprevalence were detected in Rahimyar Khan (southern Punjab) and in Jhang (central Punjab), respectively. Potential risk factors associated with seropositivity of the Q fever in camels included desert area (42.5%; OR = 2.78, 95% CI 1.12-3.21) summer season (35.7%; OR = 2.3, 95% CI: 1.31-3.2), sex (female) (39.1; OR = 2.35, 95% CI: 1.34-2.98), tick infestation (51.3%;OR = 2.81, 95% CI: 1.34-3.02), age (>10 years; 46.4%; OR = 1.56, 95% CI: 0.33-2.05) and herd size (38.5%; OR = 1.21, 95% CI: 0.76-1.54). Coxiella burnetii DNA was amplified in 12 (20%) and 1 (10%) of 60 ELISA-negative and 10 suspected camels, respectively. DNA could not be detected in ELISA positive blood pools. This study emphasizes the seroprevalence and associated risk factors of coxiellosis as well as its potential to spill over to animals and humans in contact with these camel herds.