Cellular immune response in broiler chicks inoculated with chicken embryo liver cell culture passaged inclusion body hepatitis virus

With a view to assess cellular immune response, 10 day old broiler chicks were inoculated with chick embryo liver cell culture propagated inclusion body hepatitis virus, which was passaged up to 50th passage levels. The cellular immune response in broilers as assessed by lymphocyte transformation test (LTT) using peripheral blood leucocytes (PBLs) from the group of chick to non-specific T cell mitogen ConA. The mean stimulation index (SI) value was recorded as 1.014 0.011on 7th day post inoculation which was slightly raised to the level of 1.019 0.021 on 14th day post inoculation. The higher SI value of 1.297 0.029 was recorded on day 21st post inoculation. On 2nd day post challenge infection, the SI value was decreased to the level of 1.019 0.014, however on 7th day post challenge the maximum SI value 1.324 0.022 was recorded. The increase in SI values of 50th passage level clearly indicates a better stimulation of CMI response after immunization. Where as booster effect was clearly observed after challenge.