Pathological observations in experimental pasteurellosis in Kuttanad ducks

Pasteurella multocida was inoculated in one month old ducklings via two different routes - subcutaneous and intranasal. The symptoms, mortality pattern, gross and histopathological changes of the inoculated birds were compared daily for a period of 30 days. Reisolation studies were also performed from the vital organs. The results obtained showed that the route of entry of organism played a significant role in the progression of infection, onset of mortality, number of deaths, expression of symptoms and lesions. The parentral (subcutaneous) inoculation featured more acute pattern of infection and mortality whereas the expression of symptoms and lesions were of higher degree in intranasaly inoculated birds. The immunosuppression and resultant high morbidity in duck cholera were well evidenced as there was depletion, necrosis and cystic changes in the lymphoid organs.