ISOLATION AND IDENTIFICATION OF INFECTIOUS BURSAL DISEASE VIRUS FROM AN OUTBREAK OF GUMBORO DISEASE AND PRODUCTION OF INFECTION IN EXPERIMENTAL BIRDS

Abstract

Isolation and identification of infectious bursal disease virus (IBDV) from an outbreak was based on clinico-postmortem investigation and serological test. The clinical manifestations of the affected flocks were anorexia, depression, ruffled feathers, diarrhoea and death. During postmortem examination swollen, soft and edematous with yellowish discoloration bursa of fabricious was observed. Petechial and ecchymotic haemorrhages were also observed in the leg and breast muscles. Bursae of fabricius were collected aseptically and macerated seperately in sterilized pestle and mortar to prepare a 10% (w/v) suspension in sterile PBS. Inocultion of 10% bursal homogenate @ 100 ul through intranasal, intraocular and intracloacal route of experimental birds (group-A and group-B). Group-C was kept as uninoculated control. At day 3 post infection chickens belonging to group-A and Group-B were showed clinical and postmortem lesion similar to that of naturally infected birds. Morbidity was almost 100% and mortality was 40-60% due to experimental infection. Experimental birds of Group-C were remaining normal. The antibody titer of the experimentally infected chickens at day 28-post infection was determined by indirect ELISA technique. At day 28 post inoculation chicken showed a significant antibody response as in vaccinated birds. This indicated that birds were infected by IBDV. 0.2ml of the 10% bursal suspension was inoculated on the CAM route of 10 days old embryonated indigenous 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.