Exposure to Brucella Species, Coxiella burnetii, and Trichinella Species in Recently Imported Camels from Sudan to Egypt: Possible Threats to Animal and Human Health

Brucellosis and coxiellosis/Q fever are bacterial infections caused by Brucella species and Coxiella burnetii, respectively; camels are highly susceptible to both pathogens. Trichinellosis is a parasitic infection caused by various Trichinella nematode species. Reportedly, camels are susceptible to experimental infection with Trichinella spp., but information on this potential host species is scarce. All three infections are of zoonotic nature and thus of great public health concern. The current study aimed to determine antibodies against the three pathogens in recently imported camels (n = 491) from Sudan at the two main ports for the entrance of camels into southern Egypt using commercial indirect ELISAs. Samples were collected in two sampling periods. The seropositivity rates of Brucella spp., C. burnetii, and Trichinella spp. were 3.5%, 4.3%, and 2.4%, respectively. Mixed seropositivity was found in 1% for Brucella spp. and C. burnetii. Marked differences were found between the two study sites and the two sampling periods for Brucella. A higher rate of seropositivity was recorded in the Red Sea/older samples that were collected between 2015 and 2016 (4.3%, 17/391; odds ratio = 9.4; p < 0.030) than in those collected in Aswan/recent samples that were collected between 2018 and 2021 (0/100). Concerning C. burnetii, samples collected during November and December 2015 had a significantly higher positivity rate than the other samples (13%, 13/100; OD = 4.8; p < 0.016). The same effect was observed for antibodies to Trichinella spp., with samples collected during November and December 2015 showing a higher positivity rate than the other samples (7%, 7/100; OD = 10.9; p < 0.001). This study provides valuable information on the seroprevalence of Brucella spp. and additional novel information on C. burnetii and Trichinella spp. in recently imported camels kept in quarantine before delivery to other Egyptian regions. This knowledge can be utilized to reduce health hazards and financial burdens attributable to brucellosis, Q fever, and trichinellosis in animals and humans in Egypt.

Sequencing and Characterization of αs2-Casein Gene (CSN1S2) in the Old-World Camels Have Proven Genetic Variations Useful for the Understanding of Species Diversification

The CSN1S2 gene encodes αs2-casein, the third most abundant protein in camel milk. Despite its importance in foals, human nutrition, and dairy processing, the CSN1S2 gene in camels has received little attention. This study presents the first complete characterization of the CSN1S2 gene sequence in Old-World camels (Camelus bactrianus and Camelus dromedarius). Additionally, the gene promoter, consisting of 752 bp upstream of exon 1, was analyzed. The entire gene comprises 17 exons, ranging in length from 24 bp (exons 4, 8, 11, and 13) to 280 bp (exon 17). Interesting was the identification of the exon 12 in both species. The promoter analysis revealed 24 putative binding sites in the Bactrian camel and 22 in dromedary camel. Most of these sites were typical elements associated with milk protein, such as C/EBP-α, C/EBP-β, Oct-1, and AP1. The SNP discovery showed relatively high genetic diversity compared to other camel casein genes (CSN1S1, CSN2, and CSN3), with a total of 34 polymorphic sites across the two species. Particularly noteworthy is the transition g.311G>A in the CSN1S2 promoter, creating a new putative consensus binding site for a C/EBP-β in the Bactrian camel. At the exon level, two novel variants were found. One was detected in exon 6 of the Bactrian camel (g.3639C>G), resulting in an amino acid replacement, p.36Ile>Met. The second variant was found in noncoding exon 17 of dromedary CSN1S2 (g.1511G>T). Although this mutation occurs in the 3'-UnTranslated Region, it represents the first example of exonic polymorphism in the CSN1S2 for this species. This SNP also affects the binding sites of different microRNAs, including the seed sequence of the miRNA 4662a-3p, highlighting its role as a regulatory factor for CSN1S2 gene. A PCR-RFLP was set up for genotyping a dromedary Tunisian population (n = 157), and the minor allele frequency was found to be 0.27 for the G allele, indicating a potential yield improvement margin. The interspersed elements (INEs) analysis revealed 10 INEs covering 7.34% and 8.14% of the CSN1S2 sequence in the Bactrian and dromedary camels, respectively. Furthermore, six elements (A, B, F, H, I, and L) are shared among cattle and camels and are partially found in other ruminants, suggesting a common ancestral origin of these retrotransposons. Conversely, elements C, D, E, and G are specific to camels.

Isolation and genetic characterization of MERS-CoV from dromedary camels in the United Arab Emirates

Background

The study of coronaviruses has grown significantly in recent years.Middle East respiratory syndrome coronavirus (MERS-CoV) replicates in various cell types, and quick development has been made of assays for its growth and quantification. However, only a few viral isolates are now available for investigation with full characterization. The current study aimed to isolate MERS-CoV from nasal swabs of dromedary camels and molecularly analyze the virus in order to detect strain-specific mutations and ascertain lineage classification.

Methods

We isolated the virus in Vero cells and adapted it for in vitro cultivation. The isolates were subjected to complete genome sequencing using next-generation sequencing followed by phylogenetic, mutation, and recombination analysis of the sequences.

Results

A total of five viral isolates were obtained in Vero cells and adapted to in vitro cultures. Phylogenetic analysis classified all the isolates within clade B3. Four isolates clustered close to the MERS-CoV isolate camel/KFU-HKU-I/2017 (GenBank ID: MN758606.1) with nucleotide identity 99.90-99.91%. The later isolate clustered close to the MERS-CoV isolate Al-Hasa-SA2407/2016 (GenBank ID: MN654975.1) with a sequence identity of 99.86%. Furthermore, the isolates contained several amino acids substitutions in ORF1a (32), ORF1ab (25), S (2), ORF3 (4), ORF4b (4), M (3), ORF8b (1), and the N protein (1). The analysis further identified a recombination event in one of the reported sequences (OQ423284/MERS-CoV/dromedary/UAE-Al Ain/13/2016).

Conclusion

Data presented in this study indicated the need for continuous identification and characterization of MERS-CoV to monitor virus circulation in the region, which is necessary to develop effective control measures. The mutations described in this investigation might not accurately represent the virus's natural evolution as artificial mutations may develop during cell culture passage. The isolated MERS-CoV strains would be helpful in new live attenuated vaccine development and efficacy studies.

Domestication of the Dromedary Revisited and Its Consequences for Legislation as to Keeping Livestock or Pet Animals

Being in an advanced stage of domestication is a newly proposed requirement to decide which animals can be safely kept by humans. Dutch legislators were the first to apply it and other European countries may be tempted to adopt a similar approach. Unexpectedly, the Dutch assessors considered the dromedary (Camelus dromedarius) as being insufficiently domesticated and this species will therefore no longer be able to be kept as a production animal from 2024 onwards. In a recent publication on this topic, we showed that the domestication of the dromedary is actually very advanced. In this paper, we apply the same criteria that were used by the Dutch assessors to determine the degree of domestication, taking into account the most recent scientific developments in this area, even though it should be noted that these criteria have neither been peer-reviewed, nor published in an international scientific journal. For the sake of comparison, and in order to validate the procedure, we also applied these criteria to the house cat. The results confirm that the dromedary is highly domesticated, but also that the house cat (Felis silvestris catus) is at most semi-domesticated. Obviously, we agree with the decision of the Dutch legislators to place the house cat on the positive list, but our analysis demonstrates that this was decided on false grounds. Our analysis makes it clear that the requirement of being in an advanced stage of domestication is not suitable. Instead of maintaining this requirement, we recommend implementing evidence-based, peer-reviewed methods to decide which animals can be kept by humans, and to include species specific-guidelines in the legislation on how this can be achieved safely.

MERS-CoV Found in Hyalomma dromedarii Ticks Attached to Dromedary Camels at a Livestock Market, United Arab Emirates, 2019

The main mode of transmission of Middle East respiratory syndrome-related coronavirus (MERS-CoV) between dromedaries is likely via the respiratory route. However, there must be other modes to explain how the infection is brought to MERS-CoV-negative closed herds, such as transmission by ticks. Here, we present a study performed at three different locations in the United Arab Emirates (UAE) involving 215 dromedary camels (Camelus dromedarius) and the ticks attached to them. We tested the camels and ticks via RT-(q)PCR for the presence of MERS-CoV nucleic acids, as well as flaviviruses that may be present in the region (e.g., Alkhumra hemorrhagic fever virus). Camel sera were additionally analyzed for evidence of previous exposure to MERS-CoV. In total, 8 out of 242 tick pools were positive for MERS-CoV RNA (3.3%; C_t 34.6-38.3), 7 of which contained Hyalomma dromedarii ticks, and one contained a Hyalomma sp. tick (species not identified). All of the virus-positive ticks' host camels were also positive for MERS-CoV RNA in their nasal swab samples. Short sequences established in the N gene region from two positive tick pools were identical to viral sequences from their hosts' nasal swabs. In total, 59.3% of dromedaries at the livestock market had MERS-CoV RNA in their nasal swabs (C_t 17.7-39.5). While dromedaries at all locations were negative for MERS-CoV RNA in their serum samples, antibodies were detected in 95.2% and 98.7% of them (tested by ELISA and indirect immunofluorescence test, respectively). Given the probably transient and/or low level of MERS-CoV viremia in dromedaries and the rather high C_t values observed in the ticks, it seems unlikely that Hyalomma dromedarii is a competent vector for MERS-CoV; however, its role in mechanical or fomite transmission between camels should be investigated.

Single Amino Acid Substitution in the Receptor Binding Domain of Spike Protein Is Sufficient To Convert the Neutralization Profile between Ethiopian and Middle Eastern Isolates of Middle East Respiratory Coronavirus

Middle East respiratory syndrome coronavirus (MERS-CoV) is a zoonotic virus that causes MERS, which is endemic in the Middle East. The absence of human cases in Africa despite the presence of MERS-CoV suggests virological differences between MERS-CoVs in Africa and the Middle East. In fact, in the laboratory, recombinant MERS-CoV carrying the spike (S) protein of Ethiopian isolates exhibits attenuated properties, being more easily neutralized and replicating slower than viruses carrying the S protein of Middle Eastern isolate, EMC. In this study, to identify the amino acids that define the different virological features between Ethiopian and Middle Eastern MERS-CoVs, neutralization titers and viral replication were evaluated using recombinant MERS-CoVs carrying amino acid substitution(s) in the S protein. A single amino acid difference introduced into the receptor binding domain was sufficient to reverse the difference in the neutralizing properties of the S protein between Ethiopian and Middle Eastern MERS-CoVs. Furthermore, amino acid mutations in the S1 and S2 regions of S protein were collectively involved in slow viral replication. Since even a single amino acid difference in S protein can reverse the viral properties of MERS-CoV, it should be noted that multiple mutations may induce a significant change. Careful monitoring of genetic alterations in MERS-CoVs in Africa is therefore required to detect the emergence of virulent strains generated by a few genetic differences. IMPORTANCE There have been no reported cases of human Middle East respiratory syndrome (MERS) in Africa, despite the presence of MERS coronavirus (MERS-CoV). Previous studies have shown that recombinant MERS-CoV carrying the S protein of an Ethiopian isolate replicated slower and was more easily neutralized relative to MERS-CoV carrying the S protein of a Middle Eastern isolate. In this study, we investigated the amino acid(s) in S protein associated with the different viral characteristics between Ethiopian and Middle Eastern MERS-CoVs. The results revealed that a single amino acid difference in the receptor binding domain was sufficient to reverse the neutralization profile. This implies that slight genetic changes can alter the predominant population of MERS-CoV, similar to the transition of variants of severe acute respiratory syndrome coronavirus-2. Careful genetic monitoring of isolates is important to detect the spread of possible virulent MERS-CoVs generated by mutation(s).

The Flourishing Camel Milk Market and Concerns about Animal Welfare and Legislation

The worldwide dromedary milk production has increased sharply since the beginning of this century due to prolonged shelf life, improved food-safety and perceived health benefits. Scientific confirmation of health claims will expand the market of dromedary milk further. As a result, more and more dromedaries will be bred for one purpose only: the highest possible milk production. However, intensive dromedary farming systems have consequences for animal welfare and may lead to genetic changes. Tighter regulations will be implemented to restrict commercialization of raw milk. Protocols controlling welfare of dromedaries and gene databases of milk-dromedaries will prevent negative consequences of intensive farming. In countries where dromedaries have only recently been introduced as production animal, legislators have limited expertise on this species. This is exemplified by an assessment on behalf of the Dutch government, recommending prohibiting keeping this species from 2024 onwards because the dromedary was deemed to be insufficiently domesticated. Implementation of this recommendation in Dutch law would have devastating effects on existing dromedary farms and could also pave the way for adopting similar measures in other European countries. In this paper it is shown that the Dutch assessment lacks scientific rigor. Awareness of breeders and legislators for the increasing knowledge about dromedaries and their products would strengthen the position of dromedaries as one of the most adapted and sustainable animals.

Camel (Camelus spp.) Urine Bioactivity and Metabolome: A Systematic Review of Knowledge Gaps, Advances, and Directions for Future Research

Up to the present day, studies on the therapeutic properties of camel (Camelus spp.) urine and the detailed characterization of its metabolomic profile are scarce and often unrelated. Information on inter individual variability is noticeably limited, and there is a wide divergence across studies regarding the methods for sample storage, pre-processing, and extract derivatization for metabolomic analysis. Additionally, medium osmolarity is not experimentally adjusted prior to bioactivity assays. In this scenario, the methodological standardization and interdisciplinary approach of such processes will strengthen the interpretation, repeatability, and replicability of the empirical results on the compounds with bioactive properties present in camel urine. Furthermore, sample enlargement would also permit the evaluation of camel urine's intra- and interindividual variability in terms of chemical composition, bioactive effects, and efficacy, while it may also permit researchers to discriminate potential animal-intrinsic and extrinsic conditioning factors. Altogether, the results would help to evaluate the role of camel urine as a natural source for the identification and extraction of specific novel bioactive substances that may deserve isolated chemical and pharmacognostic investigations through preclinical tests to determine their biological activity and the suitability of their safety profile for their potential inclusion in therapeutic formulas for improving human and animal health.

Seroprevalence of Toxoplasma gondii and Neospora caninum in camels recently imported to Egypt from Sudan and a global systematic review

INTRODUCTION

Toxoplasma gondii and Neospora caninum are closely related intracellular protozoan parasites of medical and veterinary concern by causing abortions and systemic illness. Limited or ambiguous data on the prevalence of T. gondii and N. caninum in camels triggered us to conduct this study.

METHODS

Camels (n = 460) recently imported from Sudan and destined mainly for human consumption, were tested for specific antibodies against these protozoans using commercially available ELISAs. From the two only quarantine stations for camels from Sudan, 368 camels were sampled between November 2015 and March 2016 in Shalateen, Red Sea governorate, and 92 samples were collected between September 2018 and March 2021 from Abu Simbel, Aswan governorate.

RESULTS & DISCUSSION

Overall, seropositive rates in camels were 25.7%, 3.9% and 0.8% for T. gondii, N. caninum and mixed infection, respectively. However, marked differences were found between the two study sites and/or the two sampling periods: For T. gondii, a higher rate of infection was recorded in the Red Sea samples (31.5%, 116/368; odds ratio 20.7, 5.0-85.6; P<0.0001) than in those collected in Aswan (2.2%, 2/92). The opposite was found for N. caninum with a lower rate of infection in the Red Sea samples (0.82%, 3/368; odds ratio 23.7, 6.7-83.9; P<0.0001) than in the samples from Aswan (16.3%, 15/92). Additionally, our systematic review revealed that the overall published seroprevalence of T. gondii and N. caninum was 28.6% and 14.3% in camels worldwide, respectively. To the best of our knowledge, this study provides the first record of seroprevalence of both T. gondii and N. caninum in recently imported camels kept under quarantine conditions before delivery to other Egyptian cities and regions. In addition, our review provides inclusive data on the prevalence of T. gondii and N. caninum in camel globally. This knowledge provides basic data for the implementation of strategies and control measures against neosporosis and toxoplasmosis.

Refining the Camelus dromedarius Myostatin Gene Polymorphism through Worldwide Whole-Genome Sequencing

Myostatin (MSTN) is a highly conserved negative regulator of skeletal muscle in mammals. Inactivating mutations results in a hyper-muscularity phenotype known as "double muscling" in several livestock and model species. In Camelus dromedarius, the gene structure organization and the sequence polymorphisms have been previously investigated, using Sanger and Next-Generation Sequencing technologies on a limited number of animals. Here, we carried out a follow-up study with the aim to further expand our knowledge about the sequence polymorphisms at the myostatin locus, through the whole-genome sequencing data of 183 samples representative of the geographical distribution range for this species. We focused our polymorphism analysis on the ±5 kb upstream and downstream region of the MSTN gene. A total of 99 variants (77 Single Nucleotide Polymorphisms and 22 indels) were observed. These were mainly located in intergenic and intronic regions, with only six synonymous Single Nucleotide Polymorphisms in exons. A sequence comparative analysis among the three species within the Camelus genus confirmed the expected higher genetic distance of C. dromedarius from the wild and domestic two-humped camels compared to the genetic distance between C. bactrianus and C. ferus. In silico functional prediction highlighted: (i) 213 differential putative transcription factor-binding sites, out of which 41 relative to transcription factors, with known literature evidence supporting their involvement in muscle metabolism and/or muscle development; and (ii) a number of variants potentially disrupting the canonical MSTN splicing elements, out of which two are discussed here for their potential ability to generate a prematurely truncated (inactive) form of the protein. The distribution of the considered variants in the studied cohort is discussed in light of the peculiar evolutionary history of this species and the hypothesis that extremely high muscularity, associated with a homozygous condition for mutated (inactivating) alleles at the myostatin locus, may represent, in arid desert conditions, a clear metabolic disadvantage, emphasizing the thermoregulatory and water availability challenges typical of these habitats.

Anatomo-topographic and histo-cytological study of dromedary's spleen in Algeria

BACKGROUND

Twenty-five spleens of adult, healthy dromedary of the local breed from the region of El Oued, Algeria, were collected at the slaughterhouse in order to carry out research to determine the macroscopic and microscopic structure of spleen in this species, macroscopic study revealed that the spleen has a rectangular shape with a triangular section, rounded edges, a little bit striated, its surface is smooth in which the aspect of the capsule and the parietal surface is shiny and smooth, the morphometric study was carried out after classifying the sampled spleen in five groups according to the animal's body weight which increases with age.

MATERIALS AND METHODS

Our study revealed that the groups show a different value of mass which declines towards a drop of the index, also the indexes of length and width are following a decreasing order.

RESULTS

The histological study revealed that the zone occupied by stroma did not exceed 26.81% of the total components of the capsule which is composed essentially of connective tissue and an inner layer of smooth muscle cells. Vascular and avascular trabeculae extend from the capsule. The immunohistochemistry study made it possible to visualise T lymphocytes of the splenic parenchyma using monoclonal antibodies where a statistical study was carried out to determine the composition of the various compartments of this organ. The localisation of immunocompetent cells in the splenic parenchyma has been elucidated with antibodies specific for T lymphocytes.

CONCLUSIONS

The red pulp occupied a maximum area of the spleen with an average of 68.1% composed of sinusoids venous, the cords extend between the sinuses and the interlobular zone contain many cells: macrophages, plasma cells, red blood cells, white blood cells and platelets.

dromedarius) Population from the United Arab Emirates

Genetic polymorphisms, causing variation in casein genes (CSN1S1, CSN1S2, CSN2, and CSN3), have been extensively studied in goats and cows, but there are only few studies reported in camels. Therefore, we aimed to identify alleles with functional roles in the United Arab Emirates dromedary camel (Camelus dromedarius) population to complement previous studies conducted on the same species. Using targeted next-generation sequencing, we sequenced all genes in the casein gene cluster in 93 female camels to identify and characterize novel gene variants. Most variants were found in noncoding introns and upstream sequences, but a few variants showed the possibility of functional impact. CSN2 was found to be most polymorphic, with total 91 different variants, followed by CSN1S1, CSN3 and CSN1S2. CSN1S1, CSN1S2 and CSN2 each had at least two variants while CSN3 had only one functional allele. In future research, the functional impact of these variants should be investigated further.

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.

Genetic Diversity and Population Structure of Dromedary Camel-Types

The dromedary camel is a unique livestock for its adaptations to arid-hot environments and its ability to provide goods under extreme conditions. There are no registries or breed standards for camels. Thus, named camel populations (i.e., camel-types) were examined for genetic uniqueness and breed status. Camel populations are generally named based on shared phenotype, country or region of origin, tribal ownership, or the ecology of their habitat. A dataset of 10 Short-Tandem Repeat markers genotyped for 701 individual camels from 27 camel-types was used to quantify genetic diversity within camel-types, compare genetic diversity across camel-types, determine the population genetic structure of camel-types, and identify camel-types that may represent true breeds. Summary statistics (genotyping call rate, heterozygosity, inbreeding coefficient FIS, and allelic frequencies) were calculated and population-specific analyses (pairwise FST, neighbor-joining tree, relatedness, Nei's genetic distance, principal coordinate analysis [PCoA], and STRUCTURE) were performed. The most notable findings were 1) little variation in genetic diversity was found across the camel-types, 2) the highest genetic diversity measure was detected in Targui and the lowest was in Awarik, 3) camel-types from Asia (especially the Arabian Peninsula) exhibited higher genetic diversity than their counterparts in Africa, 4) the highest DeltaK value of population structure separated camel-types based on geography (Asia vs. Africa), 5) the most distinct camel-types were the Omani, Awarik, and the Gabbra, 6) camel-types originating from the same country did not necessarily share high genetic similarity (e.g., camel-types from Oman), and 7) camel-type names were not consistently indicative of breed status.

High Prevalence of Genogroup I and Genogroup II Picobirnaviruses in Dromedary Camels

Picobirnaviruses (PBVs) are small non-enveloped bisegmented double-stranded RNA viruses found in humans, mammals, and birds. Increasing molecular epidemiology studies suggest a high sequence diversity of PBVs in numerous hosts and the environment. In this study, using 229 fecal samples from dromedary camels in Dubai, 52.8% were positive for PBVs, of which 77.7% and 41.3% were positive for genogroup I and II, respectively, and 19.0% were positive for both genotypes. Phylogenetic analysis showed high diversity among the sequences of genogroup I and II dromedary PBVs. Marked nucleotide polymorphisms were observed in 75.5% and 46.0% of genogroup I and II RNA-dependent RNA polymerase (RdRp) sequences, respectively, suggesting the co-existence of multiple strains in the same specimen. Both high genetic diversity and prevalence of genogroup I and II PBV in dromedaries were observed. In fact, the prevalence of genogroup II PBV in dromedaries is the highest among all animals to date. The complete/near-complete core genomes of five genogroup I and one genogroup II dromedary PBVs and partial segment 1 and 2 of both genotypes were also sequenced. The dromedary PBV genome organizations were similar to those of other animals. Genetic reassortment and mutation are both important in the ecology and evolution of PBVs.

Phylogenetic Analysis of MERS-CoV in a Camel Abattoir, Saudi Arabia, 2016-2018

We detected Middle East respiratory syndrome coronavirus (MERS-CoV) RNA in 305/1,131 (27%) camels tested at an abattoir in Al Hasa, Eastern Province, Saudi Arabia, during January 2016–March 2018. We characterized 48 full-length MERS-CoV genomes and noted the viruses clustered in MERS-CoV lineage 5 clade B.

Lower palatine developmental instability in hybrid Old World camelids

Objective:

In this research study, we explore the fluctuating asymmetry (FA) of palate Camelus hybrids and their parental species (dromedary and Bactrian).

Materials and Methods:

We studied a sample of pictures from 27 adult skulls of pure Camelus dromedarius (n = 13), Camelus bactrianus (n = 7), and their crosses (n = 7), from two different collections. A set of 11 semilandmarks was located on the palatal region and was studied by means of geometric morphometric methods. The asymmetric variation was analyzed and evaluated for allometric effects, and variation among these three groups was studied using a canonical variates analysis.

Results:

Among hybrids, there appeared a significantly lower amount of FA in comparison to the parental species, which may reflect the lower levels of genetic stress and higher levels of directional asymmetry, which may suggest the presence of strongly transgressive mastication compared to pure species.

Conclusion:

Camel hybrids would present increased developmental stability and better adaptation over those of parenteral lines.

Middle East Respiratory Syndrome Coronavirus Transmission

Middle East respiratory syndrome coronavirus (MERS-CoV) infection causes a spectrum of respiratory illness, from asymptomatic to mild to fatal. MERS-CoV is transmitted sporadically from dromedary camels to humans and occasionally through human-to-human contact. Current epidemiologic evidence supports a major role in transmission for direct contact with live camels or humans with symptomatic MERS, but little evidence suggests the possibility of transmission from camel products or asymptomatic MERS cases. Because a proportion of case-patients do not report direct contact with camels or with persons who have symptomatic MERS, further research is needed to conclusively determine additional mechanisms of transmission, to inform public health practice, and to refine current precautionary recommendations.

Housing Management of Male Dromedaries during the Rut Season: Effects of Social Contact between Males and Movement Control on Sexual Behavior, Blood Metabolites and Hormonal Balance

Simple Summary

The effect of different housing management systems on the behavior, metabolites and hormonal balance in male dromedaries during the rutting season was evaluated. Male dromedaries that were housed in groups and allowed to walk around had significantly higher frequencies of ruminating, standing, walking and sexual-related behaviors than those housed individually or tied. Movement control had significant effects on blood serum metabolites and hormone concentrations. Fenced and exercised male dromedaries had higher (p < 0.05) concentrations of blood serum transaminases, free radicals, glucose, cholesterol and testosterone and lower (p < 0.05) concentrations of cortisol and triiodothyronine (T3) than tied male dromedaries. Animal social interaction is of particular importance for maintaining physical; psychological and sexual behaviors. Allowing walking-around exercise for captive animals improves their metabolic status and decreases captive stress effects. Housing systems that guarantee social interaction and physical activity are being the most suitable housing management systems for male dromedaries during the rutting season.

Abstract

The current study aimed to evaluate the effect of different housing management systems on behavior, blood metabolites and hormonal balance in male dromedaries during the rutting season. Forty-eight adult male dromedaries were stratified in a two by three factorial experiment design, testing effects of social contact (single and group) and movement control (tied, fenced and exercise). During a ten-week experimental period, male dromedaries were filmed weekly for 20 min three times per day to evaluate their behaviors. Blood samples were collected and analyzed for serum metabolites and hormones. Both animal social contact and movement control significantly affected maintenance, posture and sexual behaviors. Male dromedaries housed in groups expressed higher frequencies of sexual desire-related behaviors (teeth grinding, open legs, tail flapping, dulla “soft palate exteriorization”, blathering and urination) than those individually housed. Animal movement control significantly affected sexual behavior; fenced and exercised male dromedaries expressed higher frequencies of sexual desire-related behaviors than tied ones. Male dromedaries housed in groups and allowed to walk around had significantly higher frequencies of ruminating, standing, walking and sexual-related behaviors than those housed individually or tied. Movement control had significant effects on blood serum metabolites and hormone concentrations. Fenced and exercised male dromedaries had higher (p < 0.05) concentrations of blood serum transaminases, free radicals, glucose, cholesterol and testosterone (2.91 and 2.09 ng/mL, respectively) and lower (p < 0.05) concentrations of cortisol (44.12 and 53.52 nmol/L, respectively) and triiodothyronine (1.68 and 1.91 ng/mL, respectively) than tied male dromedaries. In conclusion, animal social interaction is of particular importance for maintaining physical, psychological and sexual behaviors. Allowing walking-around exercise for captive animals improves their metabolic status and decreases captive stress effects. Housing systems that guarantee social interaction and physical activity are the most suitable housing management systems for captive male dromedaries during the rutting season.

Zoonotic Pathogens of Dromedary Camels in Kenya: A Systematised Review

Kenya is home to Africa’s third largest population of dromedary camels, and production at commercial and local levels are increasingly important. In pastoral and nomadic communities in the arid and semi-arid lands (ASALs), camels play a vital role in food security, while commercial milk production and formalized export markets are rapidly emerging as camel populations expand into non-traditional areas. Until recently, little focus was placed on camels as hosts of zoonotic disease, but the emergence of Middle Eastern respiratory coronavirus (MERS-CoV) in 2012, and the discovery of exposure to the virus in Kenyan camels, highlighted the need for further understanding of this area. This systematised review utilised a robust search strategy to assess the occurrence of camel-associated zoonoses in Kenya and to evaluate the quality of the published literature. Seventy-four studies were identified, covering sixteen pathogens, with an increasing number of good quality studies in recent years. Despite this, the area remains under-researched and there is a lack of robust, high-quality research. Trypanosome spp., Echinococcus granulosus and Brucella spp. appeared most frequently in the literature. Pathogens with the highest reported prevalence were MERS-CoV (0–100%), Echinococcus granulosa (7–60%) and Rift Valley fever virus (7–57%). Exposure to Brucella spp., Coxiella burnetii and Crimean-Congo haemorrhagic fever virus showed higher levels in camel or camel-associated vectors than other livestock species, although brucellosis was the only disease for which there was robust evidence linking camel and human exposure. Zoonotic agents with less severe human health outcomes, such as Dermatophilosus congolensis and contagious ecthyma, were also represented in the literature. This review provides an important summary of the scope and quality of current knowledge. It demonstrates that further research, and improved adherence to robust study design and reporting are essential if the zoonotic risk from camels in Kenya, and elsewhere, is to be better understood.

Characterization of Salmonella Frintrop isolated from dromedary camels (Camelus dromedarius)

Different studies have reported the prevalence and antibiotic resistance of Salmonella in dromedary camels and its role in camelid-associated salmonellosis in humans, but little is known about the epidemiology of Campylobacter in dromedaries. Here, we investigate the prevalence, genetic diversity and antibiotic resistance of Campylobacter and Salmonella in dromedary camels (Camelus dromedarius). A total of 54 individuals were sampled from two different dromedary farms located in Tenerife (Canary Islands, Spain). While all the samples were Campylobacter-negative, Salmonella prevalence was 5.5% (3/54), and the only serovar isolated was S. Frintrop. Pulsed-field gel electrophoresis analysis revealed a low genetic diversity, with all isolates showing a nearly identical pulsotype (similarity >95%). Our results indicate that dromedary camels could not be a risk factor for Campylobacter human infection, but seems to be a reservoir for Salmonella transmission. Since camel riding has become one of the main touristic attractions in several countries, and its popularity has increased considerably in recent years, a mandatory control, especially for zoonotic pathogens such as Campylobacter and Salmonella, should be implemented.

SNP discovery and population structure analysis in Lassi and Marecha camel breeds using a genotyping by sequencing method

Pakistani camels have been classified socio-geographically into 20 breeds, but they have not yet been subjected to substantial selective pressures and the genetic basis for these breeds is not understood. However, it should be possible to distinguish them by use of molecular data. This study investigated the genetic diversity and population structure within and between two major Pakistani camel breeds, Marecha and Lassi. As no SNP array is currently available, we first identified 63 619 SNPs using a genotyping by sequencing approach. After quality control, a panel of 36 926 SNPs was used in the analysis. Population structure was investigated with a principal coordinate analysis as well as a cluster analysis using NetView, and multilocus heterozygosity analysis to explore between- and within-breed genetic variation. In addition, between-breed variation was explored using the fixation index, F_ST . We also compared relationship matrices computed using the VanRaden SNP-based method and a method developed specifically for genotyping by sequencing data. Among the two camel breeds, Lassi showed a lower level of genetic diversity whereas Marecha showed a higher level. As a genotyping platform has not yet been developed for the camel, the SNPs discovered in this study will be useful in future genetic studies in camels.

Serologic Detection of Middle East Respiratory Syndrome Coronavirus Functional Antibodies

We developed and validated 2 species-independent protein-based assays to detect Middle East respiratory syndrome coronavirus functional antibodies that can block virus receptor-binding or sialic acid-attachment. Antibody levels measured in both assays correlated strongly with virus-neutralizing antibody titers, proving their use for serologic confirmatory diagnosis of Middle East respiratory syndrome.

Intrafollicular spontaneous parthenogenetic development of dromedary camel oocytes

Dromedary camel oocytes are unique in their capability for intrafollicular and in vitro spontaneous parthenogenetic activation (SPA) and development. This study was designed for (a) observing the incidence of SPA and development of dromedary camel oocytes retrieved from ovaries; (b) assessing intrafollicular development of dromedary camel oocytes using histological examination; (c) evaluating the abilities of dromedary camel oocytes to mature, SPA, and develop in vitro; and (d) identifying the transcript abundance of Cdx2 messenger RNA (mRNA) expression in different stages of SPA and developed camel embryos. The results revealed that 2.33% of oocytes retrieved from dromedary camel ovaries were SPA and developed to blastocyst stage. Serial sections of dromedary camel ovaries also demonstrated the presence of 1.4 SPA and parthenotes per ovary, which included from two-cell to the blastocysts with demarcated trophectoderm and inner cell mass layers. A total of 2.6% in vitro matured dromedary camel oocytes developed into morulae. The SPA and developed dromedary embryos expressed transcript abundance for Cdx2 mRNA with the highest (p < .05) at the blastocyst. The present work determines for the first time the intrafollicular oocytes from the dromedary camel display SPA, and the parthenotes can develop into blastocysts and expressing Cdx2 mRNA.

Ultrasonography of the liver in healthy and diseased camels (Camelus dromedaries)

In camels, hepatic diseases are relatively common and most of them are misdiagnosed as a cause of illness because signs may be subtle. In addition, diagnostic laboratory methods are insufficient as hepatic enzymes can also be elevated in camels with cardiac or skeletal muscle damage. Examples of liver diseases in camels are hepatic lipidosis, hepatitis, cirrhosis, hepatic necrosis, choleostasis, hyperplasia of biliary epithelium, hydatid cysts, glycogen deposition, cholangitis, cholangiohepatitis, calcified hydatid cyst and hepatic abscesses. When the liver is examined by ultrasonography, the clinician gets sufficient information about the size, position, echopatterns of the hepatic parenchyma, bile ducts and outlines of the hepatic blood vessels. Ultrasonography has been used previously in camels only for reproductive purposes. However, during the past decade, it has been used for scanning of the healthy organs as well as evaluation and determining the diagnosis and prognosis of non-reproductive disorders. Examples of diseases evaluated by ultrasonography in camels are paratuberculosis, trypanosomiasis, abdominal and urinary disorders, thoracic diseases, renal tumors, pyelonephritis, renal abscessation, gastrointestinal tumors, chronic peritonitis and splenic abscessation. Ultrasound-guidance in biopsy of hepatic lesions and in portocentesis has also been reported in camels. This mini review article is written to shed light on ultrasonography of the liver and its blood vessels in healthy camels as well as finding in camels with hepatic disorders such as fatty infiltration of the liver, hepatic abscesses and calcification of the bile ducts.

Influenza D Virus Infection in Dromedary Camels, Ethiopia

Influenza D virus has been found to cause respiratory diseases in livestock. We surveyed healthy dromedary camels in Ethiopia and found a high seroprevalence for this virus, in contrast to animals co-existing with the camels. Our observation implies that dromedary camels may play an important role in the circulation of influenza D virus.

The Major Histocompatibility Complex of Old World Camels-A Synopsis

This study brings new information on major histocompatibility complex (MHC) class III sub-region genes in Old World camels and integrates current knowledge of the MHC region into a comprehensive overview for Old World camels. Out of the MHC class III genes characterized, TNFA and the LY6 gene family showed high levels of conservation, characteristic for MHC class III loci in general. For comparison, an MHC class II gene TAP1, not coding for antigen presenting molecules but functionally related to MHC antigen presenting functions was studied. TAP1 had many SNPs, even higher than the MHC class I and II genes encoding antigen presenting molecules. Based on this knowledge and using new camel genomic resources, we constructed an improved genomic map of the entire MHC region of Old World camels. The MHC class III sub-region shows a standard organization similar to that of pig or cattle. The overall genomic structure of the camel MHC is more similar to pig MHC than to cattle MHC. This conclusion is supported by differences in the organization of the MHC class II sub-region, absence of functional DY genes, different organization of MIC genes in the MHC class I sub-region, and generally closer evolutionary relationships of camel and porcine MHC gene sequences analyzed so far.

Immunohistochemical and Ultrastructural Features of the Seasonal Changes in the Epididymal Epithelium of Camel (Camelus dromedarius)

In order to evaluate the influence of reproductive activity on the functional role of the epididymal epithelium in the Egyptian dromedary camel, Connexin-43 (Cx-43), vascular endothelial growth factor (VEGF), and androgen receptor (AR) immunoreactivity in the epididymal epithelium and the fine structure of the principal, dark, basal, apical, and halo cells were investigated. The secretory activity of the principal cells was amplified in the breeding season, while its endocytotic function became more active in the nonbreeding season. This was evidenced by punctate strong immunoreactive signals for Cx-43, which appeared to be more intense in the apical region of these epithelial cells, and the extremely long slender stereocilia (microvilli) with multiple junctional complexes. The nonbreeding principal cells revealed granular immunoreactive signals for VEGF scattered in the apical and basal cytoplasm. Ultrastructurally, both extreme vacuolation and several multivesicular inclusion bodies were observed in their cytoplasm. Dark cell size greatly diminished in the nonbreeding season and their nuclear morphology greatly changed from oval to lobulated shape. The plasma membrane of the apical cells expressed several infoldings (microvilli) in the breeding season. However, it was almost smooth in the nonbreeding season except for a small microvillus that appeared as a bleb-like projection. In some regions, a strong dense immunoreactivity for VEGF could be recognized in the cytoplasm of the apical cells and some basal ones. Halo cells with numerous multivesicular inclusions occupying most of the cytoplasm and a lobulated eccentric nucleus were detected in the nonbreeding season. In conclusion, these findings indicate that the reproductive activity has a significant impact on the immunohistochemical and ultrastructural profiles of the epithelial cells lining the Egyptian dromedary camel epididymis.

Old World camels in a modern world - a balancing act between conservation and genetic improvement

Old World camels have served humans in cross‐continental caravans, transporting people and goods, connecting different cultures and providing milk, meat, wool and draught since their domestication around 3000–6000 years ago. In a world of modern transport and fast connectivity, these beasts of burden seem to be out‐dated. However, a growing demand for sustainable milk and meat production, especially in countries affected by climate change and increasing desertification, brings dromedaries (Camelus dromedarius) and Bactrian camels (Camelus bactrianus) back onstage and into the focus of animal breeders and scientists. In this review on the molecular genetics of these economically important species we give an overview about the evolutionary history, domestication and dispersal of Old World camels, whereas highlighting the need for conservation of wild two‐humped camels (Camelus ferus) as an evolutionarily unique and highly endangered species. We provide cutting‐edge information on the current molecular resources and on‐going sequencing projects. We cannot emphasise enough the importance of balancing the need for improving camel production traits with maintaining the genetic diversity in two domestic species with specific physiological adaptation to a desert environment.

First Isolation and Rapid Identification of Newcastle Disease Virus from Aborted Fetus of Dromedary Camel Using Next-Generation Sequencing

Newcastle disease virus (NDV) causes morbidities and mortalities in wild and domestic birds globally. For humans, exposure to infected birds can cause conjunctivitis and influenza-like symptoms. NDV infections in mammals are rarely reported. In this study, using next-generation sequencing, an NDV was identified and isolated from Vero cells inoculated with the nasal swab of an aborted dromedary fetus in Dubai, during the time when an NDV outbreak occurred in a pigeon farm located in close proximity to the dairy camel farm where the mother of the aborted dromedary fetus resided, and there were a lot of pigeons in the camel farm. Genome analysis revealed that the structurally and functionally important features of other NDVs were also present in this dromedary NDV genome. Phylogenetic analysis based on the nucleotide sequences of fusion protein (F), hemagglutinin-neuraminidase protein (HN) and complete polyprotein showed that the virus belonged to sub-genotype VIg of class II NDV and is most closely related to pigeon NDVs in Egypt in the same year. The present study is the first that demonstrated isolation of NDV in dromedaries. Further study is warranted to investigate the relationship between NDV infection and abortion.

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.

Middle East Respiratory Syndrome Coronavirus in Dromedaries in Ethiopia Is Antigenically Different From the Middle East Isolate EMC

Middle East respiratory syndrome (MERS) is an emerging respiratory disease caused by the MERS coronavirus (MERS-CoV). MERS has been endemic to Saudi Arabia since 2012. The reservoir of MERS-CoV is the dromedary camel, suggesting that MERS is primarily a zoonotic disease. MERS-CoV is common in dromedaries throughout the Middle East, North Africa, and East Africa as evidenced by neutralizing antibodies against MERS-CoV; however, human cases have remained limited to the Middle East. To better understand the cause of this difference, the virological properties of African camel MERS-CoV were analyzed based on the spike (S) protein in Ethiopia. Nasal swabs were collected from 258 young dromedaries (≤ 2 years old) in the Afar region of Ethiopia, of which 39 were positive for MERS-CoV, as confirmed by genetic tests. All positive tests were exclusive to the Amibara woreda region. Using next-generation sequencing, two full-length genomes of Amibara isolates were successfully decoded; both isolates belonged to the C2 clade based on phylogenetic analysis of full-length and S protein sequences. Recombinant EMC isolates of MERS-CoV, in which the S protein is replaced with those of Amibara isolates, were then generated to test the roles of these proteins in viral properties. Amibara S recombinants replicated more slowly in cultured cells than in EMC S recombinants. In neutralizing assays, Amibara S recombinants were neutralized by lower concentrations of sera from both Ethiopian dromedaries and EMC isolate (wild-type)-immunized mouse sera, relative to the EMC S recombinants, indicating that viruses coated in the Amibara S protein were easier to neutralize than the EMC S protein. Neutralization experiments performed using S1/S2 chimeric recombinants of the EMC and Amibara S proteins showed that the neutralization profile was dependent on the S1 region of the S protein. These results suggest that the slower viral replication and the ease of neutralization seen in the Ethiopian MERS-CoV are due to strain-specific differences in the S protein and may account for the absence of human MERS-CoV cases in Ethiopia.

Improving Illumina assemblies with Hi-C and long reads: An example with the North African dromedary

Researchers have assembled thousands of eukaryotic genomes using Illumina reads, but traditional mate‐pair libraries cannot span all repetitive elements, resulting in highly fragmented assemblies. However, both chromosome conformation capture techniques, such as Hi‐C and Dovetail Genomics Chicago libraries and long‐read sequencing, such as Pacific Biosciences and Oxford Nanopore, help span and resolve repetitive regions and therefore improve genome assemblies. One important livestock species of arid regions that does not have a high‐quality contiguous reference genome is the dromedary (Camelus dromedarius). Draft genomes exist but are highly fragmented, and a high‐quality reference genome is needed to understand adaptation to desert environments and artificial selection during domestication. Dromedaries are among the last livestock species to have been domesticated, and together with wild and domestic Bactrian camels, they are the only representatives of the Camelini tribe, which highlights their evolutionary significance. Here we describe our efforts to improve the North African dromedary genome. We used Chicago and Hi‐C sequencing libraries from Dovetail Genomics to resolve the order of previously assembled contigs, producing almost chromosome‐level scaffolds. Remaining gaps were filled with Pacific Biosciences long reads, and then scaffolds were comparatively mapped to chromosomes. Long reads added 99.32 Mbp to the total length of the new assembly. Dovetail Chicago and Hi‐C libraries increased the longest scaffold over 12‐fold, from 9.71 Mbp to 124.99 Mbp and the scaffold N50 over 50‐fold, from 1.48 Mbp to 75.02 Mbp. We demonstrate that Illumina de novo assemblies can be substantially upgraded by combining chromosome conformation capture and long‐read sequencing.

Scanning electron microscopy and histomorphology of the epiglottis in dromedaries: A study revealing unusual structure with the probable functional role

While epiglottis is essentially a mammalian structure, studying its microstructure in any placental model will add an important information to the field of comparative anatomy and the related branches of biology. The aim of this study was to describe the structure of the epiglottis in dromedary camels using light and scanning electron microscopy (SEM), with reference to the possible functions. A total of 11 epiglottis cartilages from 11 larynges were used. The study revealed unusual, deeply situated glands just beneath the cartilage plate. They have unusually, wide surface-openings, while their ducts were partly located within the cartilage. This is presumed to be an adaptation to the need for rapid and efficient mucosal surface hydration in the arid conditions. The possible secretion transport mechanisms in these glands were also discussed. Furthermore, the SEM revealed for the first time, the presence of taste buds in camel epiglottis. However, in histological sections, visibility of taste buds was dependent upon the staining techniques. The taste buds were not seen with standard H& E stain, as they blended imperceptibly with the surrounding epithelium. Conversely, Mallory's trichrome showed contrasting colors, and taste buds were visible. In conclusion, camel epiglottis has an unusual structure, which may be correlated to environmental adaptation and important for the general health of upper respiratory tract in this species.

Detection and Extraction of Heparin from Camel Lungs

BACKGROUND

Heparin is an essential drug used as an anticoagulant. Access to raw material suitable for heparin extraction is critical for creating a viable business opportunity. In Saudi Arabia, large amounts of raw material with potential for heparin extraction are wasted.

OBJECTIVE

To extract heparin and low-molecular-weight heparin (LMWH) from the camel lung, and measure its potency and activity.

METHODS

Heparin preparation included three steps: extraction, electrophoretic identification, and activity measurement. Fresh lung tissue (100 g) was minced and homogenized in a blender. Crude heparin extracts were prepared using Charles's or Volpi's method with slight modifications. Heparin was purified by electrophoresis using high-purity agarose gels in barium acetate buffer. The heparin activity of purified samples was assayed spectrophotometrically using commercial heparin kits.

RESULTS

Charles's and Volpi's extraction methods were simple and easy to establish. The yield was 90 mg crude heparin per 100 g of camel lung tissue following Volpi's extraction protocol, whereas Charles's method did not yield any heparin. The separation of heparin and LMWH by gel electrophoresis resulted in sharp and clear product bands using material prepared according to Volpi's method. The heparin preparation had an anti-factor Xa activity of 37 IU/mg, indicating weak potency.

CONCLUSION

Preparation of active heparin from camel lung tissue is a technology applicable in manufacturing. Further method development is needed to increase heparin purity and potency.

Middle East Respiratory Syndrome Coronavirus Antibodies in Dromedary Camels, Bangladesh, 2015

Dromedary camels are bred domestically and imported into Bangladesh. In 2015, of 55 camels tested for Middle East respiratory syndrome coronavirus in Dhaka, 17 (31%) were seropositive, including 1 bred locally. None were PCR positive. The potential for infected camels in urban markets could have public health implications and warrants further investigation.

A rapid scoping review of Middle East respiratory syndrome coronavirus in animal hosts

Middle East respiratory syndrome coronavirus (MERS‐CoV) is an emerging zoonotic pathogen discovered in 2012. The purpose of this scoping review was to summarize the empirical evidence for MERS‐CoV in animals in order to map knowledge gaps and to extract data for modelling disease transmission in dromedary camels. A review protocol was developed a priori, and a systematic search, data extraction and summary were conducted using the Arksey and O'Malley framework. Ninety‐nine publications were identified for full review out of 1,368 unique records. Of these publications, 71 were articles in scientific journals. Ninety of the studies were observational and the remaining nine were experimental. We summarize characteristics of animal studies including study design, study population and outcomes of interest for future transmission modelling in the reservoir population. The majority of field studies reported measures of prevalence, while experimental studies provided estimates of transmission parameters that pertain to the natural course of disease.

Morphological and molecular characterization of Onchocerca fasciata (Nematoda, Onchocercidae) from dromedary camels (Camelus dromedarius) in Iran

Skin nodules of Onchocerca fasciata Railliet and Henry, 1910 (Spirurida, Onchocercidae) are a common finding in dromedary camels, though with a minimal clinical impact. There is little information about the morphology, molecular make-up and pathological impact of this parasite. Onchocerca fasciata nodules (1.3-2.1 cm in diameter and 509-841 mg in weight) were detected on the neck region in 31.5% of dromedary camels examined in Kerman province, southeastern Iran. Of 38 isolated nodules, only 23 (60.5%) contained viable worms. Measurement and morphological analyses were performed on isolated female worms by light microscopy. The identification of O. fasciata specimens was confirmed by sequence analysis of two mitochondrial genes (12S rDNA and cox1), which showed 0.4% divergence from available O. fasciata sequences. In addition, a phylogeny of filarial nematodes was constructed, based on these two mitochondrial genes and five nuclear genes (18S rDNA, 28S rDNA, MyoHC, rbp1, hsp70); this indicated that O. fasciata belongs to clade ONC3 of Onchocercidae, with representatives of the genera Onchocerca and Dirofilaria. Within the genus Onchocerca, O. fasciata is grouped with bovine parasitic species and the human parasitic Onchocerca volvulus, which suggests an impact of domestication on the radiation of the genus. Data provided here on the distribution and morphology of O. fasciata contribute to the molecular identification and phylogenetic position of the species.

Comparative histochemical analysis of glycoconjugates in the nasal vestibule of camel and sheep

While Corriedale sheep survive in a wide range of climates, which prevents them to specialize for one climatic condition only, dromedary camels strictly adapted to desert areas. This demands more adaptive mechanisms to hot, dry conditions in camels than in sheep. Being the entrance of the nasal cavity, nasal vestibule is subjected to various environmental stressors. A protective way is the lining epithelium which is cornified in camel, but not in sheep. Mucus nasal secretions also play a key role in the protection of underlyings. Additionally, arterio-venous anastomosis is present in the lamina propria of the nasal vestibule of camel. In the present paper, sugar residues in the nasal vestibule of camel were analyzed and compared with those of sheep using 14 types of lectins to explore the distribution of glycoconjugates that may help the function of camel nasal vestibule in desert environment. In camel, none of the lectins could label the basal cells of the vestibular epithelium, although the basal cells reacted with six lectins in sheep. In camel, LEL and RCA-120 markedly labeled the luminal surface. WGA, DBA, SBA, and VVA produced marked intensities on the luminal surface in sheep. The mucous glands reacted with six lectins: WGA, s-WGA, VVA, PNA, PHA-E, and PHA-L in camel, while all lectins used except s-WGA and PHA-E reacted in the sheep. In summary, great differences are observed in the glycoconjugate expression between camel and sheep. This suggests that these glycoconjugate are related to camel's tolerance for environmental stressors.

Serologic Evidence for MERS-CoV Infection in Dromedary Camels, Punjab, Pakistan, 2012-2015

Dromedary camels from Africa and Arabia are an established source for zoonotic Middle East respiratory syndrome coronavirus (MERS-CoV) infection among humans. In Pakistan, we found specific neutralizing antibodies in samples from 39.5% of 565 dromedaries, documenting significant expansion of the enzootic range of MERS-CoV to Asia.

Diversity of Middle East respiratory syndrome coronaviruses in 109 dromedary camels based on full-genome sequencing, Abu Dhabi, United Arab Emirates

Middle East respiratory syndrome coronavirus (MERS-CoV) was identified on the Arabian Peninsula in 2012 and is still causing cases and outbreaks in the Middle East. When MERS-CoV was first identified, the closest related virus was in bats; however, it has since been recognized that dromedary camels serve as a virus reservoir and potential source for human infections. A total of 376 camels were screened for MERS-Cov at a live animal market in the Eastern Region of the Emirate of Abu Dhabi, UAE. In all, 109 MERS-CoV-positive camels were detected in week 1, and a subset of positive camels were sampled again weeks 3 through 6. A total of 126 full and 3 nearly full genomes were obtained from 139 samples. Spike gene sequences were obtained from 5 of the 10 remaining samples. The camel MERS-CoV genomes from this study represent 3 known and 2 potentially new lineages within clade B. Within lineages, diversity of camel and human MERS-CoV sequences are intermixed. We identified sequences from market camels nearly identical to the previously reported 2015 German case who visited the market during his incubation period. We described 10 recombination events in the camel samples. The most frequent recombination breakpoint was the junctions between ORF1b and S. Evidence suggests MERS-CoV infection in humans results from continued introductions of distinct MERS-CoV lineages from camels. This hypothesis is supported by the camel MERS-CoV genomes sequenced in this study. Our study expands the known repertoire of camel MERS-CoVs circulating on the Arabian Peninsula.

Development of an ultrasound-guided technique for retrobulbar nerve block in dromedary camels: a cadaveric study

OBJECTIVE

Description of an ultrasound (US)-guided technique for retrobulbar nerve blockade in dromedary (Camelus dromedarius) cadavers.

STUDY DESIGN

Prospective experimental cadaveric study that was carried out in three phases: phase I: anatomical dissection and development of US-guided technique; phase II: methylene blue (MB) injection; phase III: contrast medium (CM), US-guided injections with computed tomography (CT) control.

ANIMALS

A total of 36 orbits from 18 heads were obtained from 18 dromedary cadavers.

METHODS

Phase I: anatomical dissections were carried out bilaterally, using two heads to determine needle site placement. Phase II: a US-guided, lateral, in-plane approach using one of three volumes of MB (3, 6, or 9 mL) was evaluated in six heads (four orbits per volume tested) to establish the ideal injection volume. Injections of MB that strongly stained all retrobulbar nerves were considered successful, whereas insufficient MB volumes resulted in weak or no nerve staining. Phase III: US-guided retrobulbar injection with CM was carried out using 20 orbits. Computed tomography was performed after each injection trial to determine the accuracy of needle placement and CM dispersal. An injection was judged to be successful when the CT images revealed that the needle was located within the retractor bulbi muscle cone and the CM reached the target nerves at the orbitorotundum and the optic foramina.

RESULTS

Only injection of 9 mL of MB stained the target nerves sufficiently, whereas there was no or only weak staining with 3 and 6 mL, respectively. Therefore, 9 mL of CM was used for the US-guided injections in phase III. Subsequent CT scans revealed satisfying CM distribution within the ocular muscle cone in 18 of 20 cases (90% success rate).

CONCLUSIONS AND CLINICAL RELEVANCE

US-guided retrobulbar injection in dromedary cadavers is feasible. Further research is required to assess its practicality and usefulness in vivo.

Serologic Evidence for Influenza C and D Virus among Ruminants and Camelids, Africa, 1991-2015

Influenza D virus has been identified in America, Europe, and Asia. We detected influenza D virus antibodies in cattle and small ruminants from North (Morocco) and West (Togo and Benin) Africa. Dromedary camels in Kenya harbored influenza C or D virus antibodies, indicating a potential new host for these viruses.

Parasitic diseases of camels in Iran (1931-2017) - a literature review

Parasitic diseases of camels are major causes of impaired milk and meat production, decreases in performance or even death. Some camel parasites also represent a threat to human health. About 171,500 one-humped camels (Camelus dromedarius) and 100-300 two-humped camels (Camelus bactrianus) live in Iran. Knowledge of the biodiversity of their parasites is still limited. The present review covers all information about camel parasitic diseases in Iran published as dissertations and in both Iranian and international journals from 1931 to February 2017. Ten genera of Protozoa (Trypanosoma, Eimeria, Cryptosporidium, Toxoplasma, Neospora, Sarcocystis, Besnoitia, Theileria, Babesia and Balantidium), 48 helminth species detected in the digestive system, including three species of Trematoda, four species of Cestoda, and 41 species of Nematoda, as well as helminths from other organs - Echinococcus spp., Dictyocaulus filaria, Thelazia leesei, Dipetalonema evansi and Onchocerca fasciata - have so far been described in Iranian camels. Furthermore, 13 species of hard ticks, mange mites, the myiasis flies Cephalopina titillator and Wohlfahrtia magnifica, and immature stages of the Pentastomida Linguatula serrata have also been reported from camels of Iran. Camel parasitic diseases are a major issue in Iran in terms of economics and public health. The present review offers information for an integrated control programme against economically relevant parasites of camels.

Time Course of MERS-CoV Infection and Immunity in Dromedary Camels

Knowledge about immunity to Middle East respiratory syndrome coronavirus (MERS-CoV) in dromedary camels is essential for infection control and vaccination. A longitudinal study of 11 dam-calf pairs showed that calves lose maternal MERS-CoV antibodies 5-6 months postparturition and are left susceptible to infection, indicating a short window of opportunity for vaccination.

Reference values and repeatability of the Schirmer tear tests I and II in domesticated, clinically normal dromedary camels (Camelus dromedarius)

OBJECTIVE

To determine the normal values and repeatability for Schirmer tear test (STT) in clinically normal dromedary camels and to analyze the influence of the age and gender on these values.

ANIMALS STUDIED

Thirty clinically normal dromedary camels of different ages (calves, immature, and mature).

PROCEDURES

Schirmer tear tests I and II were performed using commercial STT strips. Three measurements were obtained from each eye over three consecutive weeks, and the variance of these measurements was determined.

RESULTS

Mean values and coefficient of variation of STT I and STT II for the right and left eyes varied significantly among camel groups (P < 0.05). For STT I, the most frequently recorded values were >14-18, > 22-26, and >30-34 mm/min in calves, immature camels, and mature camels, respectively. For STT II, however, the most frequently recorded values were 7-14, >10-18, and >26-30 mm/min, respectively. The interassay coefficients of variation were 1.7-14.4% and were significantly lower in mature camels than in calves and immature camels (P < 0.05). Age was positively correlated with STT I (r = 0.81) and STT II values (r = 0.88). No significant variations were found between genders.

CONCLUSIONS

This preliminary study reports STT I and II values and repeatability in normal dromedary camels. This information may assist veterinary practitioners in complete ophthalmic examinations and in accurate diagnosis of ocular surface diseases affecting the tear film in this species.

Middle East respiratory syndrome coronavirus (MERS-CoV) in dromedary camels in Nigeria, 2015

Evidence of current and past Middle East respiratory syndrome coronavirus (MERS-CoV) infection in dromedary camels slaughtered at an abattoir in Kano, Nigeria in January 2015, was sought by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and serology. MERS-CoV RNA was detected in 14 (11%) of 132 nasal swabs and antibody in 126 (96%) of 131 serum samples. Phylogenetic analyses demonstrate that the viruses in Nigeria are genetically distinct from those reported in the Arabian peninsula.