M. K. RAHMAN1*, M. M. RAHMAN1 and M. R. AKHTER1
1=Dr. Md. Khalesur Rahman, Lecturer, Department of Microbiology, 2Dr. Md. Mostafizer Rahman, Professor, Department of Microbiology and 3Dr. Mir Rowshan Akhter, Associate Professor, Department of Microbiology, Hajee Mohammad Danesh Science & Technology University, Dinajpur, Bangladesh.
*Corresponding author’s Email: khalesur.hstu@yahoo.com
ABSTRACT
The study was conducted at the Laboratory, Department of Microbiology, Hajee Mohammad Danesh Science & Technology University, Dinajpur, Bangladesh during July to December 2012 to isolation and identification of infectious bursal disease virus from an outbreak was based on clinico-postmortem investigation and indirect ELISA test. The samples were collected from at small scale commercial poultry farm in Dinajpur district. The clinical manifestations of the affected flocks were found anorexia, depression, ruffled feathers, diarrhoea and death. During postmortem examination swollen, soft and edematous with yellowish discoloration of bursa of fabricious was observed. Petechial and echymotic haemorrhages were also observed in the leg and breast muscles. From the affected bursa of fabricious inoculum was prepared. For isolation and propagation 0.2ml of the inoculum was inoculated through the CAM route of 10 days old 15 embryonated indigenous chicken eggs then incubated and mortality was observed. Mortality of the one embryo was observed as early as 48 hours post infection .While mortality of the other embryos occurred between 3 to 6 days of inoculation. This indicated that IBDV causes mortality in inoculated embryo through CAM route. For identification serum was separated from collected blood samples of the affected farms and then performed indirect ELISA. ELISA revealed 72.22% were sero-positive for IBDV infection. For more confirmation experimental infection was done by inoculation of 0.2 ml inoculum through intranasal, intraocular and intracloacal route of experimental birds of 21 days belonging to the group-A and B, whereas group-C was kept as control (fifteen day-old-chicks grouped as A, B and C were reared up to 28 days in an isolated poultry shed). At day 3 post infection chickens belonging to group-A and B were showed clinical sign similar to that of naturally infected chickens. Chickens of group-A and C were sacrificed and observed postmortem lesions. Chickens of group-A showed postmortem lesions are similar to that of naturally infected chickens but in group-C no changes were observed. At day 28 post inoculation of chickens of Group-B showed sero-positive by indirect ELISA.
Keywords: Infectious Bursal Disease Virus (IBDV), Enzyme Linked Immunosorbent Assay (ELISA) and Chorioallantoic membrane (CAM) route.