Investigation of an Outbreak of Low Pathogenic Avian Influenza in Poultry in Bangladesh

摘要: Since March 2007, an epidemic of highly pathogenic avian influenza have been devastating in backyard and commercial poultry Bangladesh. The agents were pathotyped as H5N1. This investigation reports the result a retrospective outbreak low H9N2 parent stock chickens that occurred 2006. morbidity mortality 50% 3%, respectively during 2–3 months. egg production decreased to 36% hatchability reduced 10%. clinical signs included less feed water intake, nasal ocular discharges severe respiratory distress. On postmortem, samples including larynx, trachea lungs collected 10% neutral buffered formalin tracheal swabs, larynx tissues Falcon tube containing glycerin with antibiotic stored frozen at -70 °C. Histopathology was conducted using routine procedure. RNA extraction RT-PCR done Qiagen one step kits. Grossly, hemorrhage septum, sinuses, eyelids, found. Lungs congested. Histologically, loss mucosal epithelium, hemorrhages mononuclear cells infiltration lamina propria, blood tinged exudates laryngeal lumen observed. In few cases, goblet hypertrophied glands prominent formed cystic spaces. confirmed presence 245 bp product matrix protein gene 488 fragment H9 subtype specific haemagglutinin well 244 fragments N2 suspected samples.The study proved virus introduced Bangladesh before detection H5N1 viruses.