Pathology and molecular diagnosis of classical swine fever in Mizoram

AIM: Clinical histopathological and molecular diagnosis of classical swine fever disease in pigs of Mizoram. MATERIALS AND METHODS: Totally, 31 clinically suspected pigs from 6 districts of Mizoram were examined, and clinical symptoms were recorded. Detailed post mortem examination of all the 31 dead animals was conducted, and gross changes were recorded. Tissue samples were collected for histopathological examination and molecular diagnosis. The collected tissues (tonsil, lymph nodes, spleen) were also processed for RNA extraction. Reverse transcription polymerase chain reaction (RT-PCR) was performed to detect the specific gene fragments of classical swine fever virus (CSFV). RESULTS: Clinical examination of all the 31 suspected pigs revealed typical clinical signs of CSF. All the animals also showed typical gross and microscopic lesions of CSF. RT-PCR on tissue samples amplified the 421bp, 449bp and 735bp region of 5´NCR, non-structural protein 5B and E(rns) gene regions of CSFV, respectively. Nested PCR for internal region of E2 gene also amplified the expected product of 271bp using PCR product of whole E2 region as template DNA. CONCLUSION: CSF is highly endemic disease in Mizoram. The viral strains circulating in this region are highly virulent. The disease can be diagnosed specifically using RT-PCR.