Molecular Detection and Isolation of Chicken Astrovirus from Commercial Chicken Flocks of Kerala, India

Reduced productivity due to enteric infections in chickens is a very common challenge in the poultry industry of India. Various studies associated Chicken astrovirus (CAstV) as a common pathogen in commercial flocks exhibiting poor weight gain, stunted growth and visceral gout. However, no published report documented the detection of the virus from Kerala so far. Hence, this study was done to investigate the presence of CAstV in 50 broiler flocks from different parts of Kerala with clinical signs such as retarded growth, diarrhoea, and a mortality of 5 to 10 %. Out of the 50, five flocks were found positive for the virus by using the Reverse Transcriptase – Polymerase Chain Reaction (RT-PCR) method with the primers targeting the partial ORF1b gene of the viral nucleic acid. The viral presence was confirmed by isolation using embryonated chicken eggs (ECE), which produced notable alteration to the infected embryos. Nucleotide sequencing of the isolates revealed a high identity of up to 100 % with the other CAstV sequences retrieved from the NCBI database. The study confirms the first report of molecular detection and isolation of CAstV from the state of Kerala.