Molecular detection and pathological changes in crossbred pigs infected with classical swine fever virus

Abstract

Classical Swine Fever (CSF) remains a major transboundary disease affecting pig production, particularly in endemic regions like India. Understanding clinical progression and host response following infection is essential for disease characterisation and control. In this study, three crossbred pigs were experimentally challenged with a virulent CSFV strain under controlled conditions. Clinical evaluation revealed typical symptoms, including pyrexia, dullness, anorexia, and conjunctivitis from 3-4 days post-infection, accompanied by significant elevation in rectal temperature. Gross post-mortem examination showed characteristic lesions such as splenomegaly with infarctions, intestinal hemorrhages, and “turkey egg” appearance of kidneys, confirming the vascular and immunopathological impact of CSFV. Molecular diagnosis through PCR targeting the conserved 5′ untranslated region (5′UTR) produced specific amplicons in infected samples, verifying active viral replication. These findings collectively demonstrate the clinical, pathological, and molecular features of CSFV infection in crossbred pigs and provide baseline data for future investigations on host-virus interactions and genetic determinants of disease susceptibility.