Exploring Prokaryotic and Eukaryotic Microbiomes Helps in Detecting Tick-Borne Infectious Agents in the Blood of Camels

Abstract

Dromedary camels (Camelus dromedarius) are widely distributed in Africa, the Middle East and northern India. In this study, we aimed to detect tick-borne pathogens through investigating prokaryotic and eukaryotic microorganisms in camel blood based on a metagenomic approach and then to characterize potentially pathogenic organisms using traditional molecular techniques. We showed that the bacteria circulating in the blood of camels is dominated by Proteobacteria, Bacteroidetes, Firmicutes and Actinobacteria. At the genus level, Sediminibacterium, Hydrotalea, Bradyrhizobium and Anaplasma were the most abundant taxa. Eukaryotic profile was dominated by Fungi, Charophyta and Apicomplexa. At the genus level, Theileria was detected in 10 out of 18 samples, while Sarcocystis, Hoplorhynchus and Stylocephalus were detected in one sample each. Our metagenomic approach was successful in the detection of several pathogens or potential pathogens including Anaplasma sp., Theileria ovis, Th. separata, Th. annulate, Th. mutans-like and uncharacterized Theileria sp. For further characterization, we provided the partial sequences of citrate synthase (gltA) and heat-shock protein (groEL) genes of Candidatus Anaplasma camelii. We also detected Trypanosoma evansi type A using polymerase chain reaction (PCR) targeting the internal transcribed spacer 1 (ITS1) region. This combined metagenomic and traditional approach will contribute to a better understanding of the epidemiology of pathogens including tick-borne bacteria and protozoa in animals.

Insights into the circulating microbiome of the Atlantic and Greenland halibut populations: the role of species-specific and environmental factors

“…The utility of this approach has recently been demonstrated in clinical settings, offering a new perspective for the development of biomarkers in ecology [21][22][23][24] similar to those described for several diseases in humans 16,20,25 . In fact, the existence of a blood microbiome is a concept that is now widely accepted not only in humans but also in animals, including pigs, broiler chickens, camels, cows, goats, cats and dogs 21,23,24,[26][27][28][29] .…”

Molecular Survey of Babesia and Anaplasma Infection in Cattle in Bolivia

“…In addition, A. platys-like infection in cattle in Bolivia was first reported in this study. Although A. platys is primarily infectious and pathogenic to dogs, there is also evidence that A. platys-like infects ruminants, including cattle in Algeria, Brazil, and Egypt, goats in Tunisia, camels in Egypt, water buffalo in Thailand, sheep in Tunisia, and red deer in China [18][19][20]26,[36][37][38][39]. The sequences of A. platys-like detected in this study clustered with those detected in R. microplus in China, cattle in Egypt, and water buffalo in Thailand, and formed a distinct cluster from those reported in dogs and brown dog ticks (Figures 3 and 4).…”

“…Anaplasma platys usually infects dogs and is generally transmitted by brown dog ticks (Rhipicephalus sanguineus). However, in recent studies, strains genetically related to A. platys (A. platys-like) were detected in ruminants (sheep, goats, deer, camels, and cattle) [16][17][18][19]. For instance, a survey of beef cattle (n = 400) in the Brazilian Pantanal detected A. platys-like in 4.75% of the tested animals showing no anaemia or other clinical signs [20].…”

Tick-borne diseases in Egypt: A one health perspective

“… Cattle, humans, rodents ND Cairo, Menofia, Qena, Sinai [ [57] , [58] , [59] , [60] , [61] , [62] ] Hepatozoonosis Hepatozoon canis Dogs ND Cairo, Giza [ 63 , 64 ] Hepatozoon sp. Rodents ND Sinai [ 62 ] Theileriosis Theileria annulata Buffaloes, camels, cattle, sheep Hyalomma dromedarii, Hyalomma excavatum Aswan, Beheira, Benisuef, Dakahlia, Elminia, Fayoum, Giza, Menofia, New valley, Port Said, Qena, Qualyobia, Sharkia, Sohag [ 33 , 36 , [70] , [71] , [72] , [73] , [74] , 43 , 46 , 47 , [65] , [66] , [67] , [68] , [69] ] Theileria ovis Buffaloes, camel, cattle, equines, goats, sheep ND Aswan, Beheira, Benisuef, Cairo, Giza, Menofia, New valley, Qualyobia, Sinai [ 46 , 49 , 66 , 70 , 72 , [75] , [76] , [77] ] Theileria equi Donkey, horses, mules Rhipicephalus annulatus Alexandria, Benisuef, Cairo, Fayoum, Giza, Ismailia, Matrouh, Menofia [ 51 , …”