RESUMEN
Chicken Infectious Anaemia Virus (CIAV) is one of the potent immunosuppressive and economically important agents affecting poultry industry worldwide. Recent reports indicate the emergence of this virus in the poultry flocks of the country. The present study aimed to investigate the pathogenic potential of a recent isolate of CIAV obtained from poultry flock of Uttaranchal State, India. Twenty first day-old age Specific Pathogen Free (SPF) chicks were inoculated intramuscularly with 10(4.5) median tissue culture infective dose (TCID50) of CIAV passaged in the Marek's disease virus transformed chicken splenic T lymphocyte (MDCC-MSB 1) cell line while 15 chicks were kept as control. The CIAV isolate produced consistent clinical signs, loss in body weight gain, anaemia, low haematocrit values, bone marrow aplasia and generalized lymphoid atrophy. Mean Packed Cell Volume (PCV) value of the infected chicks was significantly low (18.22±2.22) compared to control group (34.12±4.72) at 14 day post infection (dpi). The establishment of virus infection in chicks was confirmed both at molecular and antigenic levels by Polymerase Chain Reaction (PCR) and Indirect Immunofluorescent Test (IIFT), respectively. Characteristic apoptotic pattern was also detected in the affected organs and the virus was re-isolated successfully in MDCC-MSB1 cell cultures. The present results revealed that the virus circulating in poultry flocks of Uttaranchal state is both pathogenic and immunosuppressive in nature. Extensive epidemiological studies are suggested in the poultry flocks of the country along with adaptation of appropriate diagnostic, prevention and control strategies so as to prevent economic losses caused by this important poultry pathogen.