Risk Factors Analysis for Haemoparasitic Infections and Evaluation of Detection Methods for Ehrlichiosis in Dogs

The frequency of occurrence of canine haemoparasitic diseases was analysed in relation to associated risk factors by examining the Leishman-stained thin blood smears of 400 dogs (pet 352 and stray 48) from the Ludhiana district of Punjab state, India. To compare the effectiveness of classic-immuno-molecular techniques, 50 samples suspected of ehrlichiosis were tested by buffy coat smear examination, Immuno-chromatographic lateral flow assay (LFA-Ec) and Polymerase chain reaction (Ec-PCR) based diagnosis by amplification of a fragment of the E. canis virB9. The occurrence of haemoparasites was 6.00% with the highest prevalence of B. gibsoni (3.75%), followed by H. canis (1.25%), E. canis (0.5%), B. canis (0.25%) and Trypanosoma evansi (0.25%) with higher prevalence of haemoparasites in stray dogs (8.33%) than pet dogs (5.68%). Exercise intolerance and fever were significantly (p≤0.01) associated with occurrence of haemoparasites. The kappa value revealed “slight” and “fair” strength of agreement for LFA-Ec & Ec-PCR with buffy coat smear examination. A sensitivity of 100% and specificity of 4.26% & 68.09% was observed respectively for LFA-Ec & Ec-PCR when compared with buffy coat smear examination. The complete sequence of the virB9 gene of E. canis showed the closest homology with the isolates obtained from the USA strain. This study underscores the importance of accurate diagnostic techniques and the influence of various risk factors on the prevalence of haemoparasitic diseases in dogs.