Detection of Rickettsia amblyommatis in Amblyomma mixtum and Rhipicephalus microplus Ticks Collected from Cattle in Tamaulipas, Mexico.

Background: Rickettsia spp. are obligate intracellular bacteria of utmost importance for public health and the economy since their presence can generate significant losses in livestock production, affecting the health of animals, the quality of the meat, milk, and other products derived from affected animals. Therefore, prevention of the transmission of these pathogens, their early identification and timely treatment are essential to mitigate their impact on public health and animal production. Materials and Methods: In the present work, hard ticks were collected from infested Bos indicus cattle in Aldama, Tamaulipas, Mexico. They were identified by morphology using dichotomous keys and by sequencing and analyzing of a fragment of the mitochondrial 16S. PCR was performed using specific primers targeting Rickettsia sp. gltA. Phylogenetic analyses were performed, aligning the amino acid sequences with Muscle, and a phylogenetic tree was generated using PhyML. Results and Conclusions: Amblyomma mixtum and Rhipicephalus microplus ticks infesting the cattle were identified. Using molecular techniques, the presence of Rickettsia amblyommatis was identified in the cohort of analyzed ticks, suggesting a circulation of this pathogen in livestock in this region and granting further research in this area.