Diagnosis of pulmonary aspergillosis in geese by histopathological and microbiological methods

In this study, we aimed to determine the presence of pulmonary aspergillosis by histopathological and microbiological methods in geese that are economically grown in Kars region of Turkey. Totally 150 lung tissue samples of geese, an average age of 9 weeks, which died between 2013 and 2020 and were brought to our department were included in the study. Following the systemic necropsy paraffin blocks were prepared from the tissue samples and stained with Hematoxylin & Eosin (H&E) in order to detect histopathological changes. In order to reveal the presence of Aspergillus fungi, Periodic acid–Schiff (PAS) staining was applied to the sections as suggested by Facepath company. The microbiological examination of the tissue samples was carried out by the standard mycological culture technique on Sabouraud Dextrose Agar and by the phenotypical characterization of the emerged cultures. Various clinical symptoms such as difficulties in breathing, wheezing, weakness, anorexia, depression, diarrhea and nervous signs were recorded in geese. We observed large and small multifocal yellowish-white nodular structures in the lungs and air sacs macroscopically. In the histopathological examination of the lung tissues, we detected granulomatous structures with varying numbers and sizes. We diagnosed the Aspergillus agents in 20 (13.33%) of the tissue samples by detecting structures resembling typical tree branches in the middle of granulomatous structures with PAS staining. An identical positivity was obtained by the microbiological method and the emerged agent was solely identified as Aspergillus fumigatus with the growth pattern and macroscopic and microscopic morphological features. In conclusion, we found the presence of aspergillosis as 13.33% by histopathological and microbiological methods in geese which were brought to our department between 2013-2020. Based on these data, we concluded that aspergillosis is one of the most important infectious diseases among the goose deaths in Kars region of Turkey