Molecular detection of Ehrlichia canis and Anaplasma phagocytophilum and hematological changes of infected dogs

Abstract

Ehrlichiosis and anaplasmosis are tick-borne diseases caused by bacteria of the genera Ehrlichia and Anaplasma. Since clinical manifestations are varied and nonspecific, the diagnosis in clinical practice, remains a challenge for veterinarians. Furthermore, the distribution of these infections includes areas where its tick vector, Rhipicephalus sanguineus is present. This study was designed to evaluate the prevalence and factors associated with the presence of Ehrlichia canis and Anaplasma phagocytophilum in dogs from the central area of Tamaulipas. PCR screened 384 canine blood samples obtained from different veterinary clinics and a shelter. The data were analyzed using the Chi-square test (P level <0.05 for statistical significance). The results showed that 103 (26.8\%) out of 384 samples were positive for E. canis, while A. phagocytophilum was not detected. Statistical analysis did not show relationship between E. canis and variables like gender, breed, and origin (P.0.05). Nonetheless, there was a statistically significant difference between infected adult dogs (15-84 months) compared to other age groups evaluated (p<0.05). Regarding hematocrit, platelets count, plasma protein, total and differential white blood cells counts, none of these parameters were significantly different (P>0.05).