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Clostridium perfringens de type A a été isolé dans différents organes et dans l'intestin de jeunes dromadaires âgés de 3 à 5 semaines, morts de nécrose du muscle cardiaque. Aucun autre agent pathogène bactérien n'a été isolé. L'isolement de virus sur deux lignées cellulaires différentes, dont une culture de cellules cutanées foetales de dromadaire s'est également avéré négatif. Les souris ayant reçu des injections de filtrats dépourvus de bactéries préparés à partir de contenus intestinaux de jeunes dromadaires autopsiés sont mortes après 1 à 6 h, révélant la présence de toxines clostridiennes. Nos résultats montrent que la nécrose du muscle cardiaque est provoquée par les toxines de Clostridium perfringens de type A.

African horse sickness (AHS) is a viral disease of equids, caused by a virus of the genus Orbivirus, family Reoviridae. The African horse sickness virus (AHSV) genome is made up of ten double-stranded RNA (dsRNA) segments that together code for seven structural and four nonstructural proteins. AHS is endemic in sub-Saharan countries. The efficacy and safety of inactivated AHS vaccines containing all nine serotypes, produced at the Central Veterinary Research Laboratory (CVRL) in Dubai, United Arab Emirates have been proven in the past. All nine AHSV serotypes were isolated from 102 samples collected in the last 20 years from horse fatalities in seven different area of Kenya, Africa. CVRL inactivated AHS vaccines are used in a few African countries defining the importance of this present study to compare the genome sequences of the nine AHSV serotypes isolated from horse fatalities in Kenya and nine AHSV serotypes isolated in South Africa. The hypothesized serotypes of the newly sequenced AHSV field strains from Kenya were likewise confirmed in this investigation, and they show substantial sequence homologies with recently isolated AHSV field strains., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Six horses were challenged experimentally with a strain of Burkholderia pseudomallei isolated from a fatal case of the infection in a dromedary camel years earlier in the Emirate of Dubai. Three horses were inoculated subcutaneously and in 3 the bacterium was administered by the oral route. Four of the horses became serologically positive based on reactions to one or more of the OIE described tests for glanders. B. pseudomallei was re-isolated from the 4 serological positive horses. Only one of the subcutaneously infected horses, developed fever for 3 days. The white blood cell values and the neutrophil counts were also elevated. The study confirmed that existing serological test for diagnosing glanders cannot differentiate between glanders and melioidosis in horses.

We present the first molecular characterisation based on MLVA and SNP analysis of a strain of Burkholderia mallei isolated from a mule found dead in Brazil in 2016., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Little is known regarding the molecular epidemiology of Middle East respiratory syndrome coronavirus (MERS-CoV) circulating in dromedaries outside Saudi Arabia. To address this knowledge gap, we sequenced 10 complete genomes of MERS-CoVs isolated from 2 live and 8 dead dromedaries from different regions in the United Arab Emirates (UAE). Phylogenetic analysis revealed one novel clade A strain, the first detected in the UAE, and nine clade B strains. Strain D998/15 had a distinct phylogenetic position within clade A, being more closely related to the dromedary isolate NRCE-HKU205 from Egypt than to the human isolates EMC/2012 and Jordan-N3/2012. A comparison of predicted protein sequences also demonstrated the existence of two clade A lineages with unique amino acid substitutions, A1 (EMC/2012 and Jordan-N3/2012) and A2 (D998/15 and NRCE-HKU205), circulating in humans and camels, respectively. The nine clade B isolates belong to three distinct lineages: B1, B3 and B5. Two B3 strains, D1271/15 and D1189.1/15, showed evidence of recombination between lineages B4 and B5 in ORF1ab. Molecular clock analysis dated the time of the most recent common ancestor (tMRCA) of clade A to March 2011 and that of clade B to November 2011. Our data support a polyphyletic origin of MERS-CoV in dromedaries and the co-circulation of diverse MERS-CoVs including recombinant strains in the UAE.

A new hepatitis E virus (HEV-7) was recently found in dromedaries and 1 human from the United Arab Emirates. We screened 2,438 dromedary samples from Pakistan, the United Arab Emirates, and 4 African countries. HEV-7 is long established, diversified and geographically widespread. Dromedaries may constitute a neglected source of zoonotic HEV infections.

Although antibodies against West Nile virus (WNV) have been detected in the sera of dromedaries in the Middle East, North Africa and Spain, no WNV has been isolated or amplified from dromedary or Bactrian camels. In this study, WNV was isolated from Vero cells inoculated with both nasal swab and pooled trachea/lung samples from a dromedary calf in Dubai. Complete-genome sequencing and phylogenetic analysis using the near-whole-genome polyprotein revealed that the virus belonged to lineage 1a. There was no clustering of the present WNV with other WNVs isolated in other parts of the Middle East. Within lineage 1a, the dromedary WNV occupied a unique position, although it was most closely related to other WNVs of cluster 2. Comparative analysis revealed that the putative E protein encoded by the genome possessed the original WNV E protein glycosylation motif NYS at E154-156, which contained the N-linked glycosylation site at N-154 associated with increased WNV pathogenicity and neuroinvasiveness. In the putative NS1 protein, the A70S substitution observed in other cluster 2 WNVs and P250, which has been implicated in neuroinvasiveness, were present. In addition, the foo motif in the putative NS2A protein, which has been implicated in neuroinvasiveness, was detected. Notably, the amino-acid residues at 14 positions in the present dromedary WNV genome differed from those in most of the closely related WNV strains in cluster 2 of lineage 1a, with the majority of these differences observed in the putative E and NS5 proteins. The present study is the first to demonstrate the isolation of WNV from dromedaries. This finding expands the possible reservoirs of WNV and sources of WNV infection.

Background: Among all known picornaviruses, only two species, equine rhinitis A virus and equine rhinitis B virus (ERBV) are known to infect horses, causing respiratory infections. No reports have described the detection of ERBV in fecal samples of horses and no complete genome sequences of ERBV3 are available., Methods: We performed a molecular epidemiology study to detect ERBVs in horses from Dubai and Hong Kong. Complete genome sequencing of the ERBVs as well as viral loads and genome, phylogenetic and evolutionary analysis were performed on the positive samples., Results: ERBV was detected in four (13.8 %) of the 29 fecal samples in horses from Dubai, with viral loads 8.28 × 10(3) to 5.83 × 10(4) copies per ml, but none of the 47 fecal samples in horses from Hong Kong by RT-PCR. Complete genome sequencing and phylogenetic analysis showed that three of the four strains were ERBV3 and one was ERBV2. The major difference between the genomes of ERBV3 and those of ERBV1 and ERBV2 lied in the amino acid sequences of their VP1 proteins. The Ka/Ks ratios of all the coding regions in the ERBV3 genomes were all <0.1, suggesting that ERBV3 were stably evolving in horses. Using the uncorrelated lognormal distributed relaxed clock model on VP1 gene, the date of the most recent common ancestor (MRCA) of ERBV3 was estimated to be 1785 (HPDs, 1176 to 1937) and the MRCA dates of ERBV1 and ERBV2 were estimated to be 1848 (HPDs, 1466 to 1949) respectively., Conclusions: Both acid stable (ERBV3) and acid labile (ERBV2) ERBVs could be found in fecal samples of horses. Detection of ERBVs in fecal samples would have implications for their transmission and potential role in gastrointestinal diseases as well as fecal sampling as an alternative method of identifying infected horses.

Recently, we reported the discovery of a dromedary camel coronavirus UAE-HKU23 (DcCoV UAE-HKU23) from dromedaries in the Middle East. In this study, DcCoV UAE-HKU23 was successfully isolated in two of the 14 dromedary fecal samples using HRT-18G cells, with cytopathic effects observed five days after inoculation. Northern blot analysis revealed at least seven distinct RNA species, corresponding to predicted subgenomic mRNAs and confirming the core sequence of transcription regulatory sequence motifs as 5'-UCUAAAC-3' as we predicted previously. Antibodies against DcCoV UAE-HKU23 were detected in 58 (98.3%) and 59 (100%) of the 59 dromedary sera by immunofluorescence and neutralization antibody tests, respectively. There was significant correlation between the antibody titers determined by immunofluorescence and neutralization assays (Pearson coefficient = 0.525, p < 0.0001). Immunization of mice using recombinant N proteins of DcCoV UAE-HKU23 and Middle East respiratory syndrome coronavirus (MERS-CoV), respectively, and heat-inactivated DcCoV UAE-HKU23 showed minimal cross-antigenicity between DcCoV UAE-HKU23 and MERS-CoV by Western blot and neutralization antibody assays. Codon usage and genetic distance analysis of RdRp, S and N genes showed that the 14 strains of DcCoV UAE-HKU23 formed a distinct cluster, separated from those of other closely related members of Betacoronavirus 1, including alpaca CoV, confirming that DcCoV UAE-HKU23 is a novel member of Betacoronavirus 1.

Middle East respiratory syndrome coronavirus (MERS-CoV) was detected by monoclonal antibody-based nucleocapsid protein-capture enzyme-linked immunosorbent assay (ELISA), RNA detection, and viral culture from the nasal sample of a 1-month-old dromedary calf in Dubai with sudden death. Whole genome phylogeny showed that this MERS-CoV strain did not cluster with the other MERS-CoV strains from Dubai that we reported recently. Instead, it formed a unique branch more closely related to other MERS-CoV strains from patients in Qatar and Hafr-Al-Batin in Saudi Arabia, as well as the MERS-CoV strains from patients in the recent Korean outbreak, in which the index patient acquired the infection during travel in the eastern part of the Arabian Peninsula. Non-synonymous mutations, resulting in 11 unique amino acid differences, were observed between the MERS-CoV genome from the present study and all the other available MERS-CoV genomes. Among these 11 unique amino acid differences, four were found in ORF1ab, three were found in the S1 domain of the spike protein, and one each was found in the proteins encoded by ORF4b, ORF5, envelope gene, and ORF8. MERS-CoV detection for all other 254 dromedaries in this closed dairy herd was negative by nucleocapsid protein-capture ELISA and RNA detection. MERS-CoV IgG sero-positivity gradually increased in dromedary calves with increasing age, with positivity rates of 75% at zero to three months, 79% at four months, 89% at five to six months, and 90% at seven to twelve months. The development of a rapid antigen detection kit for instantaneous diagnosis is warranted.Emerging Microbes & Infections (2015) 4, e74; doi:10.1038/emi.2015.74; published online 2 December 2015.

Highly pathogenic avian influenza viruses (HPAIVs) of subtype H5N1 have continued to perpetuate with divergent genetic variants in poultry within Asia since 2003. Further dissemination of Asian-derived H5 HPAIVs to Europe, Africa and, most recently, to the North American continent has occurred. We report an outbreak of HPAIV H5N1 among falcons kept for hunting and other wild bird species bred as falcon prey in Dubai, United Arab Emirates, during the autumn of 2014. The causative agent was identified as avian influenza virus subtype H5N1, clade 2.3.2.1c, by genetic and phylogenetic analyses. High mortality in infected birds was in accordance with systemic pathomorphological and histological alterations in affected falcons. Genetic analysis showed the HPAIV H5N1 of clade 2.3.2.1c is a reassortant in which the PB2 segment was derived from an Asian-origin H9N2 virus lineage. The Dubai H5N1 viruses were closely related to contemporary H5N1 HPAIVs from Nigeria, Burkina-Faso, Romania and Bulgaria. Median-joining network analysis of 2.3.2.1c viruses revealed that the Dubai outbreak was an episode of a westward spread of these viruses on a larger scale from unidentified Asian sources. The incursion into Dubai, possibly via infected captive hunting falcons returning from hunting trips to central Asian countries, preceded outbreaks in Nigeria and other West African countries. The alarmingly enhanced geographical mobility of clade 2.3.2.1.c and clade 2.3.4.4 viruses may represent another wave of transcontinental dissemination of Asian-origin HPAIV H5 viruses, such as the outbreak at Qinghai Lake caused by clade 2.2 (‘Qinghai’ lineage) in 2005.

Camels carry Middle East respiratory syndrome coronavirus, but little is known about infection age or prevalence. We studied >800 dromedaries of all ages and 15 mother-calf pairs. This syndrome constitutes an acute, epidemic, and time-limited infection in camels <4 years of age, particularly calves. Delayed social separation of calves might reduce human infection risk.

The recent discovery of Middle East Respiratory Coronavirus and another novel dromedary camel coronavirus UAE-HKU23 in dromedaries has boosted interest in search of novel viruses in dromedaries. In this study, fecal samples of 203 dromedaries in Dubai were pooled and deep sequenced. Among the 7330 assembled viral contigs, 1970 were assigned to mammalian viruses. The largest groups of these contigs matched to Picobirnaviridae, Circoviridae, Picornaviridae, Parvoviridae, Astroviridae and Hepeviridae. Many of these viral families were previously unknown to dromedaries. In addition to the high abundance of contigs from Circoviridae (n=598 with 14 complete genomes) and Picobirnaviridae (n=1236), a high diversity of contigs from these two families was found, with the 14 Circoviridae complete genomes forming at least five clusters and contigs from both genogroup I and genogroup II potentially novel picobirnaviruses. Further studies comparing the incidence of these viral families in healthy and sick dromedaries will reveal their pathogenic potential., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: Glanders, caused by the gram-negative bacterium Burkholderia mallei, is a highly infectious zoonotic disease of solipeds causing severe disease in animals and men. Although eradicated from many Western countries, it recently emerged in Asia, the Middle-East, Africa, and South America. Due to its rareness, little is known about outbreak dynamics of the disease and its epidemiology., Methodology/principal Findings: We investigated a recent outbreak of glanders in Bahrain by applying high resolution genotyping (multiple locus variable number of tandem repeats, MLVA) and comparative whole genome sequencing to B. mallei isolated from infected horses and a camel. These results were compared to samples obtained from an outbreak in the United Arab Emirates in 2004, and further placed into a broader phylogeographic context based on previously published B. mallei data. The samples from the outbreak in Bahrain separated into two distinct clusters, suggesting a complex epidemiological background and evidence for the involvement of multiple B. mallei strains. Additionally, the samples from Bahrain were more closely related to B. mallei isolated from horses in the United Arab Emirates in 2004 than other B. mallei which is suggestive of repeated importation to the region from similar geographic sources., Conclusion/significance: High-resolution genotyping and comparative whole genome analysis revealed the same phylogenetic patterns among our samples. The close relationship of the Dubai/UAE B. mallei populations to each other may be indicative of a similar geographic origin that has yet to be identified for the infecting strains. The recent emergence of glanders in combination with worldwide horse trading might pose a new risk for human infections.

In a molecular epidemiology study of hepatitis E virus (HEV) in dromedaries in Dubai, United Arab Emirates, HEV was detected in fecal samples from 3 camels. Complete genome sequencing of 2 strains showed >20% overall nucleotide difference to known HEVs. Comparative genomic and phylogenetic analyses revealed a previously unrecognized HEV genotype.

Middle East respiratory syndrome coronavirus (MERS-CoV) has caused an ongoing outbreak of severe acute respiratory tract infection in humans in the Arabian Peninsula since 2012. Dromedary camels have been implicated as possible viral reservoirs. We used serologic assays to analyze 651 dromedary camel serum samples from the United Arab Emirates; 151 of 651 samples were obtained in 2003, well before onset of the current epidemic, and 500 serum samples were obtained in 2013. Recombinant spike protein-specific immunofluorescence and virus neutralization tests enabled clear discrimination between MERS-CoV and bovine CoV infections. Most (632/651, 97.1%) camels had antibodies against MERS-CoV. This result included all 151 serum samples obtained in 2003. Most (389/651, 59.8%) serum samples had MERS-CoV-neutralizing antibody titers >1,280. Dromedary camels from the United Arab Emirates were infected at high rates with MERS-CoV or a closely related, probably conspecific, virus long before the first human MERS cases.

Background: Brucellosis in livestock causes enormous losses for economies of developing countries and poses a severe health risk to consumers of dairy products. Little information is known especially on camel brucellosis and its impact on human health. For surveillance and control of the disease, sensitive and reliable detection methods are needed. Although serological tests are the mainstay of diagnosis in camel brucellosis, these tests have been directly transposed from cattle without adequate validation. To date, little information on application of real-time PCR for detection of Brucella in camel serum is available. Therefore, this study was performed to compare the diagnostic efficiency of different serological tests and real-time PCR in order to identify the most sensitive, rapid and simple combination of tests for detecting Brucella infection in camels., Findings: A total of 895 serum samples collected from apparently healthy Sudanese camels was investigated. Sudan is a well documented endemic region for brucellosis with cases in humans, ruminants, and camels. Rose Bengal Test (RBT), Complement Fixation Test (CFT), Slow Agglutination Test (SAT), Competitive Enzyme Linked Immunosorbant Assay (cELISA) and Fluorescence Polarization Assay (FPA) as well as real-time PCR were used. Our findings revealed that bcsp31 kDa real-time PCR detected Brucella DNA in 84.8% (759/895) of the examined samples, of which 15.5% (118/759) were serologically negative. Our results show no relevant difference in sensitivity between the different serological tests. FPA detected the highest number of positive cases (79.3%) followed by CFT (71.4%), RBT (70.7%), SAT (70.6%) and cELISA (68.8%). A combination of real-time PCR with one of the used serological tests identified brucellosis in more than 99% of the infected animals. 59.7% of the examined samples were positive in all serological tests and real-time PCR. A subpopulation of 6.8% of animals was positive in all serological tests but negative in real-time PCR assays. The high percentage of positive cases in this study does not necessarily reflect the seroprevalence of the disease in the country but might be caused by the fact that the camels were imported from brucellosis infected herds of Sudan, accidentally. Seroprevalence of brucellosis in camels should be examined in confirmatory studies to evaluate the importance of brucellosis in this animal species., Conclusion: We suggest combining bcsp31 real-time PCR with either FPA, CFT, RBT or SAT to screen camels for brucellosis.

We confirm a natural infection of dromedaries with glanders. Multilocus variable number tandem repeat analysis of a Burkholderia mallei strain isolated from a diseased dromedary in Bahrain revealed close genetic proximity to strain Dubai 7, which caused an outbreak of glanders in horses in the United Arab Emirates in 2004.

Staphylococcus aureus is a common cause of mastitis and other diseases in camels. In order to obtain data on population structure as well as on the carriage of toxin genes and resistance markers, a collection of 45 isolates from dromedaries of Dubai, United Arab Emirates, were genotyped. These isolates belonged to clonal complexes CC6 (twenty isolates; 44.44%), CC30 (sixteen isolates; 35.56%), CC188 (five isolates; 11.11%), CC152 (1 isolate, 2.2%) and to a previously un-described sequence type (ST1755: arcc-18, aroe-115, glpf-6, gmk-2 pta-109, tpi-50 and yqil-2; three isolates; 6.67%). Resistance genes proved to be rare. Only three out of 45 isolates (6.67%) carried the beta-lactamase operon. The tetracycline resistance gene tetK was also detected in three isolates (6.67%). Neither the mecA gene, defining MRSA, nor other resistance genes were found. Common virulence markers included leukocidin genes lukD+lukE (in twenty-five isolates; 55.56%), the staphylokinase gene sak (twenty-two isolates; 48.89%), the enterotoxin gene cluster egc (fifteen isolates; 33.33%), and a distinct variant of the enterotoxin A gene (sea-320E, GenBank AY196686.1; thirteen isolates; 28.89%). One CC152 isolate was positive for genes encoding the Panton-Valentine leukocidin (lukF-PV+lukS-PV). This study provides first genotyping data on the population structure and the presence of toxin genes and resistance markers of S. aureus strains in Middle Eastern camels., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Background: The in vivo diagnosis of glanders relies on the highly sensitive complement fixation test (CFT). Frequently observed false positive results are troublesome for veterinary authorities and cause financial losses to animal owners. Consequently, there is an urgent need to develop a test with high specificity. Hence, a Western blot assay making use of a partly purified lipopolysaccaride (LPS) containing antigen of three Burkholderia mallei strains was developed. The test was validated investigating a comprehensive set of positive and negative sera obtained from horses and mules from endemic and non endemic areas., Results: The developed Western blot assay showed a markedly higher diagnostic specificity when compared to the prescribed CFT and therefore can be used as a confirmatory test. However, the CFT remains the test of choice for routine testing of glanders due to its high sensitivity, its feasibility using standard laboratory equipment and its worldwide distribution in diagnostic laboratories., Conclusions: The CFT should be amended by the newly validated Western blot to increase the positive likelihood ratio of glanders serodiagnosis in non endemic areas or areas with low glanders prevalence. Its use for international trade of horses and mules should be implemented by the OIE.

Background: The Houbara bustard (Chlamydotis undulata) is a wild seasonal breeding bird populating arid sandy semi-desert habitats in North Africa and the Middle East. Its population has declined drastically during the last two decades and it is classified as vulnerable. Captive breeding programmes have, hitherto, been unsuccessful in reviving population numbers and thus radical technological solutions are essential for the long term survival of this species. The purpose of this study was to investigate the use of primordial germ cell-mediated chimera technology to produce viable Houbara bustard offspring., Methodology/principal Findings: Embryonic gonadal tissue was dissected from Houbara bustard embryos at eight days post-incubation. Subsequently, Houbara tissue containing gonadal primordial germ cells (gPGCs) was injected into White Leghorn chicken (Gallus gallus domesticus) embryos, producing 83/138 surviving male chimeric embryos, of which 35 chimeric roosters reached sexual maturity after 5 months. The incorporation and differentiation of Houbara gPGCs in chimeric chicken testis were assessed by PCR with Houbara-specific primers and 31.3% (5/16) gonads collected from the injected chicken embryos showed the presence of donor Houbara cells. A total of 302 semen samples from 34 chimeric roosters were analyzed and eight were confirmed as germline chimeras. Semen samples from these eight roosters were used to artificially inseminate three female Houbara bustards. Subsequently, 45 Houbara eggs were obtained and incubated, two of which were fertile. One egg hatched as a male live born Houbara; the other was female but died before hatching. Genotyping confirmed that the male chick was a pure-line Houbara derived from a chimeric rooster., Conclusion: This study demonstrates for the first time that Houbara gPGCs can migrate, differentiate and eventually give rise to functional sperm in the chimeric chicken testis. This approach may provide a promising tool for propagation and conservation of endangered avian species that cannot breed in captivity.

Three strains of Gram-negative, rod-shaped, non-spore-forming bacteria (M 2040(T), M 1973 and M 1878-SK2), isolated from milk of camels at a camel-milk production farm in the United Arab Emirates, were investigated for their taxonomic allocation. On the basis of 16S rRNA gene sequence similarities, all three strains were shown to belong to the Alphaproteobacteria and were most closely related to Chelatococcus asaccharovorans and Chelatococcus daeguensis (95.1 and 95.2 % sequence similarity to the respective type strains). meso-Diaminopimelic acid was detected as the characteristic peptidoglycan diamino acid. The predominant compound in the polyamine pattern was spermidine, and sym-homospermidine was not detectable. The quinone system was ubiquinone Q-10. The polar lipid profile included the major compounds phosphatidylcholine and diphosphatidylglycerol and moderate amounts of phosphatidylethanolamine, phosphatidylglycerol, an unidentified glycolipid and two unidentified aminolipids. Minor lipids were also detected. The major fatty acid profile, consisting of C₁₉ :₀ cyclo ω8c and C₁₈:₁ ω7c, with C₁₈ :₀3-OH as the major hydroxylated fatty acid, was similar to those of the genus Chelatococcus. The results of DNA-DNA hybridization experiments and physiological and biochemical tests allowed both genotypic and phenotypic differentiation of the isolates from described Chelatococcus species. Isolates M 2040(T), M 1973 and M 1878-SK2 were closely related on the basis of DNA-DNA reassociation and therefore represent a single novel species. In summary, low 16S rRNA gene sequence similarities of 95 % with Chelatococcus asaccharovorans and marked differences in polar lipid profiles as well as in polyamine patterns support the description of a novel genus and species to accommodate these strains, for which the name Camelimonas lactis gen. nov., sp. nov. is proposed. The type strain of Camelimonas lactis is M 2040(T) (=CCUG 58638(T) =CCM 7696(T)).

We report a case of a 64-year-old veterinarian working in a state camel veterinary laboratory who was diagnosed with and treated for acute brucellosis with complicating epididymo-orchitis. Genomic tandem repeat analysis (MLVA-16) revealed identical Brucella strains in patient cultures and from different dromedary milk samples positive for Brucella melitensis, thereby confirming the diagnosis of a laboratory acquired infection. The case illustrates the high (airborne) infectivity of brucellosis in laboratory settings and the need to implement vigorous bio-safety measures in veterinary laboratories handling camel specimen diagnostic veterinary laboratory.

In this study, we demonstrate the use of somatic cell nuclear transfer to produce the first cloned camelid, a dromedary camel (Camelus dromedarius) belonging to the family Camelidae. Donor karyoplasts were obtained from adult skin fibroblasts, cumulus cells, or fetal fibroblasts, and in vivo-matured oocytes, obtained from preovulatory follicles of superstimulated female camels by transvaginal ultrasound guided ovum pick-up, were used as cytoplasts. Reconstructed embryos were cultured in vitro for 7 days up to the hatching/hatched blastocyst stage before they were transferred to synchronized recipients on Day 6 after ovulation. Pregnancies were achieved from the embryos reconstructed from all cell types, and a healthy calf, named Injaz, was born from the pregnancy by an embryo reconstructed with cumulus cells. Genotype analyses, using 25 dromedary camel microsatellite markers, confirmed that the cloned calf was derived from the donor cell line and the ovarian tissue. In conclusion, the present study reports, for the first time, establishment of pregnancies and birth of the first cloned camelid, a dromedary camel (C. dromedarius), by use of somatic cell nuclear transfer. This has opened doors for the amelioration and preservation of genetically valuable animals like high milk producers, racing champions, and males of high genetic merit in camelids. We also demonstrated, for the first time, that adult and fetal fibroblasts can be cultured, expanded, and frozen without losing their ability to support the development of nuclear transfer embryos, a technology that may potentially be used to modify fibroblast genome by homologous recombination so as to generate genetically altered cloned animals.

Background: The internationally mandatory complement fixation test (CFT) for testing of equine sera for the absence of glanders has repeatedly led to discrepant results. Not only do "false positive" sera pose a problem for the diagnostician and the animal health authorities but they can also result in significant financial losses for the animal owners.Due to the very low prevalence of glanders in the horse population it is of major importance to use tests with a high specificity to overcome unreliable predictive values. We have compared formalin-fixed B. mallei whole cell antigen and a well characterised mouse monoclonal antibody with regard to their specificity and sensitivity for glanders serodiagnosis using CFT, an indirect (i) and a competitive (c) ELISA platform., Results: Our results show that the CFT is still a very reliable technique in horse populations with very low glanders prevalence. The cELISA has a high sensitivity and specificity comparable to that of the CFT. The cELISA offers the possibility for automatisation, can be applied to non-complement fixing sera and used for various host species., Conclusion: The CFT is still the method of choice for testing horses for the absence of glanders.

A virus was isolated from aborted dromedary (Camelus dromedarius) fetuses during an abortion storm in Dubai, United Arab Emirates. Laboratory investigations showed the causative agent to be indistinguishable from equine rhinitis A virus (ERAV), a picornavirus. Two pregnant dromedaries experimentally infected with the camel virus isolate both aborted and an identical virus was reisolated from both fetuses, thus confirming the diagnosis. The extremely high prevalence of antibody (>90 %) and the high titres recorded against ERAV in the dromedary herd clearly showed that ERAV does infect dromedaries. Unlike horses, where ERAV targets the upper respiratory tract, in dromedaries the target organ appears to be the genital tract.

A PCR assay targeting the metalloprotease gene (mprA) of Burkholderia pseudomallei was developed for the specific detection of this organism in pure cultures and clinical samples. All other closely related organisms including B. mallei the causative agent of glanders, and B. thailandensis tested negative. Burkholderia pseudomallei DNA was successfully amplified from paraffin-embedded lung tissue of a camel with a generalized B. pseudomallei infection. The developed PCR assay can be used as a simple tool for the specific and sensitive detection of B. pseudomallei.

Since 1990 the number of glanders outbreaks in race, military and pleasure horses in Asia and South America is steadily increasing. Glanders, which is eradicated in Western Europe, Australia and Northern America, is currently considered a re-emerging disease. Consequently, the disease may be introduced into glanders-free regions by subclinical carriers at any time. The causative agent of glanders, Burkholderia (B.) mallei, is highly contagious and leads to chronic disease in horses whereas in donkeys and mules the disease is acute and often fatal. Occurrence of the disease leads to international trading restrictions and infected animals immediately have to be culled and safely disposed off. In humans B. mallei infection results in a severe clinical course, and is fatal without appropriate therapy. Its pathogenicity makes B. mallei a potential biological agent that may be used in bioterroristic attacks. Due to the eradication of glanders in the second half of the last century, veterinarians in western European countries are no longer familiar with its clinical presentation in solipeds. Having these facts in mind, this review describes the epidemiology, clinical signs, pathology and the current eradication strategy of this interesting zoonosis. Pictures of imported endurance horses infected with glanders taken during an eradication campaign in Dubai, United Arab Emirates, in 2004 illustrate most typical clinical findings.

A polymerase chain reaction (PCR) assay targeting the flagellin P (fliP)-I S407A genomic region of Burkholderia mallei was developed for the specific detection of this organism in pure cultures and clinical samples from a recent outbreak of equine glanders. Primers deduced from the known fliP-IS407A sequence of B. mallei American Type Culture Collection (ATCC) 23344(T) allowed the specific amplification of a 989-bp fragment from each of the 20 B. mallei strains investigated, whereas other closely related organisms tested negative. The detection limit of the assay was 10 fg for purified DNA of B. mallei ATCC 23344(T). B. mallei DNA was also amplified from various tissues of horses with a generalized B. mallei infection. The developed PCR assay can be used as a simple and rapid tool for the specific and sensitive detection of B. mallei in clinical samples.

Background: Burkholderia mallei is a potential biological agent that causes glanders or farcy in solipeds, a disease notifiable to the Office International des Epizooties (OIE). The number of reported outbreaks has increased steadily during the last decade, but diagnosis is hampered by the low bacterial load in infected tissues and excretions., Methods: We developed a B. mallei-specific 5'-nuclease real-time PCR assay that targets the fliP gene of B. mallei and includes an internal amplification control. Specificity was assessed with 19 B. mallei strains, 27 Burkholderia pseudomallei strains, other Burkholderia strains of 29 species, and clinically relevant non-Burkholderia organisms., Results: Amplification products were observed in all B. mallei strains but in no other bacteria. The linear range of the B. mallei real-time PCR covered concentrations from 240 pg to 70 fg of bacterial DNA/reaction. The detection limit was 60 fg of B. mallei DNA. The clinical applicability of the assay was demonstrated by use of organ samples from diseased horses of a recent outbreak that was reported to the OIE by the United Arab Emirates in 2004., Conclusions: Compared with conventional PCR, our rapid 5'-nuclease real-time PCR assay for the specific identification of B. mallei has a lower risk of carryover contamination and eliminates the need for post-PCR manipulations. This real-time PCR assay also shortens the turnaround time for results and has the potential for automation.

Burkholderia mallei causes glanders or farcy in solipeds, a disease that must be reported to the OIE (Office International des Epizooties, Paris, France). The number of reported outbreaks has increased steadily during the last decade. Serodiagnosis is hampered by the considerable number of false-positives and -negatives of the internationally prescribed tests. The major problem leading to low sensitivity and specificity of complement fixation test (CFT) and enzyme-linked immunosorbent assay (ELISA) has been linked to the test antigens currently used, i.e. crude preparations of whole cells. Future perspectives for the development and evaluation of serological test kits using well-characterized single antigens are discussed in the light of recent molecular research on B. mallei and the closely related saprozoonotic agent B. pseudomallei.

Ten common kestrels (Falco tinnunculus) were used for this falcon herpes vaccine experiment. Four kestrels were subcutaneously given 1 ml of an attenuated falcon herpesvirus that had originally been isolated from the liver of an American prairie falcon (Falco mexicanus). This virus was then passaged 100 times on chicken embryo fibroblast cells (CEF-cells). Another 4 kestrels were given subcutaneously an inactivated falcon herpesvirus vaccine derived from the same American field strain. This vaccine was concentrated, inactivated by heat and betapropiolactone and emulsified in complete Freund's adjuvans. Two further kestrels served as controls and were not vaccinated. Twenty-one days after vaccination, all 10 kestrels were challenged with passage 3 of the American falcon herpesvirus. The 2 control kestrels died 6 days after challenge and 3 of those given the inactivated herpes vaccine died 9 days after challenge, with typical lesions of herpesvirus inclusion body hepatitis. Before the vaccination experiment, all 10 kestrels were free of serum neutralising antibodies to the falcon herpesvirus. Twenty-one days after vaccination, all 4 kestrels vaccinated with the attenuated vaccine, and one vaccinated with the killed vaccine, had seroconverted, having shown no symptoms to the challenge with a low passage virulent American herpesvirus strain. Following the challenge their antibody titres to falcon herpesvirus increased. No herpesvirus was isolated from any of the cloacal swabs taken during this experiment, indicating that there is no danger for any other birds from the attenuated herpesvirus vaccine. This experiment clearly shows that an attenuated falcon herpesvirus vaccine can protect kestrels from fatal inclusion body hepatitis.

During the spring of 1995, 1996 and 1997 following tests on six peregrine falcons (Falco peregrinus) and two gyr falcons (Falco rusticolus), Salmonella typhimurium was isolated from liver, spleen and small intestines. Four of the falcons (two peregrines and two gyrs) had also contracted Chlamydia infection, three peregrines a pox infection and one peregrine a Herpesvirus infection. It is believed that this dual infection was fatal for these birds. The disease was marked by anorexia, dehydration and green-coloured droppings. Necropsy of all falcons revealed discolouration of the liver and enlargement of liver and spleen. Miliary necrosis was detected in all livers. A total of 12 salmonella serovars, including S. typhimurium, were cultured from faeces of 48 falcons which showed no clinical signs.

Clostridium perfringens type A was isolated from different organs and intestines from three to five weeks old camel calves which have died from heart muscle necrosis. No other bacterial pathogens were isolated. Virus isolation on two different cell lines including a fetal camel skin were also negative. Mice which were injected with bacteria free filtrates prepared from intestinal contents of necropsied camel calves died after one to six hours demonstrating the presence of clostridial toxins. Our findings suggest that the cardiac muscle necrosis is caused by Clostridium perfringens type A toxins.

Camels which are bred for the purpose of racing were tested serologically for 6 different animal diseases. The group were split into racing and breeding camels. The following results were achieved: Brucellosis, breeding camels 2%, racing camels 6.6%; Chlamydiosis 24%, 15%; Leptospirosis 2.5%, 5.6%; BVD/MD 9.2%, 3.6%. No antibodies were detected against IBR/IPV- and EBL-virus. The results are discussed under an epidemiological point of view.