Molecular Detection and Pathotyping of Newcastle Disease Virus in Pigeons from Karnataka, India

Abstract

Background: Newcastle disease (ND) is most important devastating diseases of poultry and it causes huge economic losses to poultry farmers throughout the world. One of the limiting factors in controlling the disease’s spread is the wide host range. While pigeons are highly susceptible and produce neurological signs of the disease. ND was suspected in five dead pigeons and detection of Avian Paramyxovirus-1 (APMV-1) in pigeons (Columba livia domestica) was confirmed by Reverse Transcriptase PCR (RT-PCR). Methods: Spleen, lung and trachea were collected and lysates were propagated in allantoic fluids for haemagglutination (HA) by chicken erythrocytes and pigeon convalescent serum inhibited haemagglutination (antibody titers greater than 1/16). Result: A 356 bp product was amplified from infected allantoic fluid by targeting a partial Fusion protein gene, including its cleavage site. Pigeon sample isolates were grown in specific pathogen Free (SPF) embryonated chicken eggs (ECE) showed virulent pathotype based on embryonic mean death time (MDT) of 42 hours and the intra-cerebral pathogenicity index (ICPI) in day-old chicks was 1.8. This is the first instance of APMV-1 identification in Karnataka with the possibility of a disease spillover in pigeons. In this scenario, more epidemiological works are suggested for surveillance of NDV in pigeons in this area of work along with implementation of suitable prevention and control measures.