DETERMINATION OF SERUM ANTIBODY TITER WITH CLINICO-PATHOLOGICAL INVESTIGATION AGAINST INFECTIOUS BURSAL DISEASE VIRUS IN DIFFERENT SMALL SCALE COMMERCIAL BROILERS

Abstract

This study was carried out to evaluate the seroprevalence of Infectious Bursal Disease Virus (IBDV) antibody with clinico-pathological investigation in different small scale commercial broilers in Dinajpur. The clinical manifestations of the affected flocks were anorexia, depression, ruffled feathers, diarrhoea and death. Swollen, soft and edematous with yellowish discoloration bursa of fabricious were observed in pathological investigarion. Petechial and ecchymotic haemorrhages were also observed in the leg and breast muscles. Bursae of fabricius were collected aseptically and were used for histopathological investigation. Mild to heavy necrosis and depletion of bursal follicle and inflammation of follicular septa were found on histopathological investigation. Inoculum were inoculated on the CAM route of 10 days old, 10 embryonated chicken eggs. Mortality of the one embryo was observed as early as 48 hours post infection .While mortality of the other embryos occurred between days 3 to 6 of inoculation. This indicated that IBDV causes mortality in inoculated embryo through CAM route. A total of 90 broilers were randomly sampled for sera collection. The indirect Enzyme Linked Immunosorbent Assay (ELISA) was the technique used for antibody detection. The result showed the presence of IBDV antibody in 25 (27.78 %) of birds evaluated while 65 (72.22%) were negative. Most of birds show seronegative but the antibody level is very low that’s might be unvaccinated or ineffective vaccine used resulting protective antibody level is not increased. So the birds might be infected any time with IBDV and shows high mortality.