Abstract
Introduction: Ticks are the obligate blood-feeding parasites responsible for transmitting various pathogens to domestic animals and humans. Ticks and tick-borne diseases are a continuous threat to livestock development in tropical and subtropical areas of the globe. To the best of our knowledge, this was the first study on the microbiome population of Hyalomma spp. infesting livestock in Pakistan.
Methods: Ticks were collected from hemo-parasite-positive cattle and were identified using standard entomological keys. Then, selected ticks were kept in the biochemical oxygen demand (BOD) incubator for egg laying and hatching at optimum temperature and humidity. A total of 16 (saliva and gut) samples were amplified through the reverse line blotting (RLB) primer of which 9 out of 16 were positive. Out of 9 positive samples, 4 samples of saliva and 5 samples of gut showed a polymerase chain reaction (PCR) product of 390 bp on 1.5% agarose gel stained with cyber green safe gel dye. Similarly, all 16 samples were amplified through the PCR by applying primers specific to the genus Anaplasma. Out of 16 amplified samples (8 saliva and 8 gut), 9 samples exhibited a positive amplification of 345 bp on 1.5% Agarose gel. After the identification of the genus, all 16 samples were subjected to species identification through PCR by applying primers specific to Theileria annulata, Babesia bovis, and Babesia bigemina.
Results: The results indicated that 9 out of 16 samples are positive for Theileria, showing a PCR product of 460 bp on Agarose gel, while none of the single samples was positive for B. bovis and B. bigemina, respectively. Overall, 16 samples were subjected to metagenomics analysis within the saliva and gut of Hyalomma ticks, and consequently, Anaplasma and T. annulata were identified. Hence, it was found that the Hyalomma tick reported in Pakistan is responsible for the transmission of T. annulata and Anaplasma spp., and both parasites are responsible for causing theileriosis and anaplasmosis in cattle.
Conclusion: It can be concluded that Hyalomma anatolicum transmits both T. annulata and Anaplasma species but not Babesia species in cattle. Thus, H. anatolicum ticks are potent vectors for T. annulata and Anaplasma species.