PATHOLOGICAL INVESTIGATION OF INFECTIOUS BURSAL DISEASE (IBD) IN SONALI CHICKEN AT DINAJPUR DISTRACT

Abstract

The study was designed to investigate the prevalence and pathology of Infectious Bursal Disease (IBD) of Sonali chicken at different upazilas in Dinajpur district in a short six month duration starting from July to December 2018. Eight Sonali chickens farms with sum of 7750 birds of various age group from four different upazila like Sadar, Chirirbandar, Parbatipur, Birol, were suspected for Infectious Bursal Disease (IBD). On the basis of detail about farm history, clinical signs, and postmortem investigation of infected chicks, the prevalence of IBD was 8.95%, 36.5%, 49.16% and 35.45% in Sadar, Chirirbandar, Parbatipur and Birol of Dinajpur District respectively. On the basis of age group, the prevalence of IBD was 41.90%, 33.11%, 28.38% and 28.24% at the age of 3rd, 4th, 5th and 6 th week of age (table 3), respectively. The prevalence of IBD in Sonali chickens was the highest 41.90% at the 3rd week of age and the lowest 28.24% at 6th week of age. No sonali chick was identified as positive for IBD in their first two weeks of age. The prevalence of vaccinated birds was 25.29% and non vaccinated birds were 49.16%. The necropsy findings of infected chick’s revealed were hemorrhages in the breast muscle and thigh muscles. The main changes were enlarged, edematous and swollen bursa of Fabricius. Histopathological study revealed the findings are destruction of normal architecture and reducing size of the follicle. Thickening of the intermolecular space. Therefore, it was concluded that susceptibility of chicks to IBD is influenced by its age, ruffled feather, depression, whitish diarrhoea with haemorrhagic muscles and inflamed, edematous, hyperemic Bursa of Fabricious is attributable to Infectious Bursal Disease.