Haematological and Biochemical Profiles of Dogs with PCR-Detected Canine Monocytic Ehrlichiosis Compared with Apparently Healthy Dogs in Hisar, India

Background: Canine monocytic ehrlichiosis (CME) is associated with variable haematological and serum biochemical abnormalities. This hospital-based study compared laboratory measurements in dogs positive for an Ehrlichia canis p28-target polymerase chain reaction (PCR) assay with those of apparently healthy dogs. Methods: Between May 2024 and February 2025, 50 dogs presenting with signs suggestive of CME at the Veterinary Clinical Complex, Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, India, underwent thin blood-smear examination and conventional PCR. Nineteen PCR-positive dogs (G1) and six apparently healthy dogs (G2) were included in comparative haematological and biochemical analyses; values were summarised as means ± standard errors. Results: PCR positivity was 19/50 (38%), whereas morula-like inclusions were seen in 2/50 (4%). Mean haemoglobin was 7.27 ± 0.40 versus 12.27 ± 0.32 g/dL, packed cell volume was 24.92 ± 1.43% versus 38.27 ± 0.80%, and platelet count was 93.58 ± 11.06 versus 306.00 ± 27.70 × 10³/mm³ in G1 and G2, respectively. Albumin was lower (1.84 ± 0.09 vs 3.31 ± 0.15 g/dL), globulin was higher (4.55 ± 0.29 vs 2.44 ± 0.32 g/dL), and the albumin:globulin ratio was lower (0.44 ± 0.04 vs 1.45 ± 0.16). Blood urea nitrogen was higher (50.76 ± 12.19 vs 4.82 ± 2.19 mg/dL) and random glucose lower (84.74 ± 4.89 vs 111.30 ± 3.82 mg/dL) in G1; the original unadjusted comparisons identified these differences at the nominal p < .05 threshold. Conclusion: In this selected clinical sample, PCR-detected CME was accompanied by lower erythrocyte indices and platelet counts, altered serum protein fractions, and differences in selected metabolic measurements. The small control group and incomplete information on disease stage, possible co-infections, and statistical assumptions limit the strength of causal or prognostic inferences.