Pathology and molecular characterization of field isolates of chicken anaemia virus circulating in commercial poultry in and around Punjab Andrabi Syedah Asma1*, Kimi Laltlan2, Deka Dipak3, Gupta Kuldip1, Singh Amarjit1 1Department of Veterinary Pathology, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana – 141004, Punjab 2Department of Veterinary Pathology, College of Veterinary and Animal Husbandry Central Agricultural University, Jalukie, Peren District, Nagaland – 797110 3Department of Veterinary Biotechnology, College of Veterinary Science, Khanapara, Assam Agricultural University, Guwahati Campus, Guwahati-781022, Assam, India. Address for Correspondence Dr. Syedah Asma Andrabi, Department of Veterinary Pathology, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana-141004, Punjab, India, E-mail: syedahasmaandrabi@gmail.com
Abstract The present study was undertaken to investigate the presence of chicken anaemia viruses (CAVs) in commercial poultry flocks and molecular characterization of circulating CAVs to determine their pathogenic potential. Study was conducted in 100 poultry birds from four poultry farms located in and around Punjab. After thorough post mortem examination of birds, tissue samples from lymphoid organs (thymus, spleen and bursa) showing lesions were collected in 10% neutral buffered formalin for histopathological changes and a part of each tissue sample was also stored at -20oC for molecular studies. By using Polymerase chain reaction (PCR), twenty-six (26) cases were found positive for CAV by at least one primer set, out of the three primer sets i.e. VP1, VP2 and VP3, yielding a product size of 1390bp, 713bp and 367bp, respectively. Three CAV positive samples from three different poultry farms were sent for sequencing of VP1, VP2 and VP3 genes. The bioinformatics analysis of genes and protein sequencing indicated that the local CAVs under study were highly pathogenic due to mutation at position 394 of amino acid sequence in VP1 gene, which is the major genetic determinant of pathogenicity and were closely related with each other as well as with a previously reported CAV strains of Punjab and Guwahati. Phylogenetic analysis based on the nucleotide sequence alignment revealed that the Punjab CAVs did not form any group with the already known genotypes, rather they formed a distinct and separate group indicating distinct genetic identities of the local viral strains. Further, details on characterization of the circulating CAVs will be required to understand the molecular epidemiology which may help in adaptation of suitable disease control and prevention measures. Top Keywords Chicken anaemia virus (CAV), Histopathology molecular characterization, Phylogenetic analysis, Polymerase chain reaction (PCR), Poultry. Top |