Clinico-pathological and necropsy findings in a 4-month old mixed-breed pup with canine parvovirus-2 infection and its genetic characterization

A four-month-old male mixed breed dog was presented with a complaint of continuous vomition, bloody diarrhea, anorexia since last five days. Physical examination revealed hypothermia, pale conjunctival mucus membrane, tachycardia, eupnea and poor body condition on the day of presentation. Fecal sample examination using commercial kit confirmed the presence of canine parvovirus-2. Viral DNA was isolated from fecal sample followed by PCR confirmation, cloning, sequencing and phylogenetic analysis which revealed it as CPV-2a variant. Hematology revealed anemia, leukopenia, decreased segmented neutrophil counts with increase in the band neutrophil counts. Plasma biochemistry revealed hypercholesterolemia with increased activities of aspartate aminotransferase, creatinine kinase and lactate dehydrogenase whereas decreased levels of amylase and chloride. In spite of aggressive therapy, the dog succumbed to its injuries on the day of presentation and hence, necropsy was performed with owner’s consent. Gross necropsy changes of the small intestine revealed blood-tinged foul hemorrhagic fluid. There were focal round to ovoid ulcerative lesions with punched-out Peyer’s patches which were slightly depressed and covered with yellowish thick exudates. The liver was enlarged, soft, friable and showed icteric change with distended gall bladder. The spleen was enlarged and congested. The lung showed consolidation and hemorrhages in diaphragmatic lobes. The kidney was found to be congested. The urinary bladder showed thickened wall and hemorrhagic lesions on the mucosal surface. Histopathology of intestinal tissue revealed complete loss of villi, crypts \u0026 columnar cells with severe inflammation of the submucosa.