Vol. 7, Issue 11 (2018)

Author(s):
Pooja Kundu, Gulshan Narang, Sushma Kajal, Pravesh Kumari and Babu Lal Jangir

Abstract:
An experiment was planned to study the effect of live infectious bursal disease vaccines in broiler chickens. One hundred and fifty day old broiler chicks were reared for 45 days and divided into A, B1, B2, C1, C2 group. Chicks of group A were acted as control. Chicks of group B1, B2 were vaccinated with commercially available intermediate plus vaccine P while in chicks of group C1, C2 vaccine Q was used. Chicks were vaccinated on 17 days of age as decided by maternal antibody titer. Booster vaccination was done in group B2 and C2 with respective vaccines P and Q. Bursal index and histopathological changes were studied in Bursa of Fabricius on 1,7, 14 days of age and 7, 14, 21, 28 days post vaccination (DPV). Histopathology showed lymphoid depletion, medullary necrosis with cyst formation, fibrous connective tissue proliferation in vaccinated groups which was initiated earlier with vaccine Q. Bursal index was comparable with control in case of birds vaccinated with vaccine P at 7 DPV only. However, it was reduced significantly in birds vaccinated with vaccine Q at 7 DPV itself. Later the bursal index was significantly lower in all the vaccinated groups vaccinated with either of the vaccine at 14, 21, 28 DPV. The present study revealed that vaccine Q seemed to be little more invasive as compared to vaccine P as it induces the immunosuppressive changes in bursa at 7 DPV itself.