Hematobiochemical, serological, and molecular detection of Anaplasma marginale in dromedary camels (Camelus dromedarius) in Al-Najaf desert, Iraq

Background and Aim

Anaplasmosis, an underestimated disease transmitted by ticks, is widespread in ruminants, such as the Arabian camel (dromedary camel). This study aimed to examine the presence of Anaplasma marginale in dromedary camels in the Al-Hiadyia region of the Al-Najaf desert, Iraq, using serological and molecular tests. Moreover, hematological and biochemical changes in infected animals were compared with those in healthy controls.

Materials and Methods

The study was conducted on 30 healthy and 260 infected camels with severe anemia, pale mucus membranes, and progressive emaciation to investigate antibodies against A. marginale using indirect enzyme-linked immunosorbent assay, followed by polymerase chain reaction for selected positive samples targeting a specific region of A. marginale major surface protein 5 (MSP5). In addition, hematological and biochemical parameters were measured to indicate the effect of the disease on blood profile, mineral status, and liver and kidney functions.

Results

Enzyme-linked immunosorbent assay analysis and microscopic examination revealed that 115/260 (44.23%) and 87 (33.46%) camels were positive for Anaplasma spp., respectively. The MSP5 gene, which is unique to A. marginale, was amplified. The results of hematological analysis indicated a significant decrease in total red blood cells, hemoglobin, and packed cell volume and a significant increase in mean corpuscular volume in infected camels, but no difference in mean corpuscular hemoglobin concentration. Moreover, there was a significant increase in total white blood cells count, lymphocytes, erythrocyte sedimentation rate, and platelets. The results of biochemical analysis indicated a significant increase in the levels of aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase, blood urea nitrogen, creatinine, and iron and a decrease in copper in infected camels. Cholesterol and triglyceride showed no significant variations between healthy and diseased camels.

Conclusion

To the best of our knowledge, this is the first molecular study to demonstrate the presence of A. marginale in dromedary camels in Iraq. The MSP5 gene is a valuable and unique diagnostic target for identifying A. marginale.

Proportion and seasonality of blood parasites in animals in Mosul using the Veterinary Teaching Hospital Lab data

Several local studies have examined evidence of blood parasites in different animals in Mosul; however, information about the most prevalent parasite and the seasonality of the infection remains limited. The objective of the study conducted here was to investigate the proportion and seasonality of blood parasites in animals in Mosul using the Veterinary Teaching Hospital Lab data. Laboratory records for a period of 25 months were used for data retrieval. In all included animals, Giemsa-stained blood smears were examined by an attending clinical pathologist for the presence of parasites. Seasons were assigned on a basis of examination date, and the seasonality was quantified by estimating season-to-season ratio. The results indicated that 61.77% of examined animals were tested positive for blood parasites. The most evident parasites were Trypanosoma spp., Theileria spp., Babesia spp., and then Anaplasma spp., with evidence of mixed infection. The odds of the infection did not significantly vary in different age groups. There was a marked linear pattern in the seasonality of the infection with Trypanosoma spp. and Anaplasma spp. An increase of the infection during spring and autumn with Theileria spp. and Babesia spp. was also evident. In conclusion, infection with blood parasites in different animals in Mosul is common with substantial burden, the effect of age-related infection is negligible, and the seasonality of the infection is evident.

Molecular Investigation on Tick-Borne Hemoparasites and Coxiella burnetii in Dromedary Camels (Camelusdromedarius) in Al Dhafra Region of Abu Dhabi, UAE

Camels represent an important resource for inhabitants of the most arid regions of the world and their survival is mainly related to environment conditions including the risk of parasitic diseases, which may represent a significant cause of losses in livestock production of these areas. Camels may be parasitized by several hematophagous arthropods, which can be vectors of several diseases including zoonosis. This study aimed to investigate in dromedary camels and their ticks the importance of tick-borne hemoparasites that might be responsible for a recent and obscure morbidity of camels in Al Dhafra region of Abu Dhabi, UAE. Blood samples and ticks from 93 naturally infected camels belonging to 36 herds, affected by variable acute clinical syndromes lasting from 3 to 5 days, were analyzed through molecular techniques for specific DNA presence of different blood pathogens: Anaplasmamarginale/Anaplasmaovis, Anaplasma phagocytophilum, Coxiella burnetii,Babesia spp., and Theileria spp. DNA. All the 72 ticks collected belonged to the Hyalomma dromedarii species and were negative for blood pathogens. n = 15 camels (16.1%) were found positive to the following tick-borne hemoparasites: A. phagocytophilum 11 (11.8%), Coxiella burnetii 3 (3.2%), and Babesia/Theileria spp. 2 (2.1%). One singular camel showed coinfection of C. burnetii and A. phagocytophiulm. Genetic profile of C. burnetii showed a high phylogenetic relatedness to European, Asian and African C. burnetii strains. This is the first laboratory investigation on tick-borne pathogens in camels in UAE, and the first report of A. phagocytophilum and C. burnetii. Moreover, since the detected pathogens are recognized pathogens for humans, this study highlights the zoonotic risk for humans working in camel husbandry.