Feed as cause of aspergillosis in flock of Turkey poults

Abstract

Aspergillosis is frequent fungal disease of different avian and mammal species, caused by fungi of genus Aspergillus. The disease is characterized by inflammatory changes in the respiratory system and sometimes has generalized onset when more organ systems are affected. These fungi are well known aflatoxin producers which, besides other microorganisms, can also be found in feed raw materials. However, the presence of fungi is not a proof of mycotoxins contamination, because they are produced in specific conditions. In this paper are presented results of examination of a flock of turkey poults, 21 days old, at one farm in Serbia. Clinical signs of central nervous system disorder were observed. After necropsy, in ten out of twelve necropsied turkey poults multiple yellowish-white granulomas on lungs were found. In nine out of twelve necropsied turkey poults solitary yellowishwhite granuloma on sagital section of the cerebrum or cerebellum were found. Mycological finding revealed fungi Aspergillus fumigatus. Two stain methods were used: haematoxylin-eosin (HE) and Grocott methenamine silver (GMS). Histopathological analysys of lung and brain has revealed the presence of granulomatous foci and caseous necrosis with surrounding region of proliferation including giant cells, macrophages, heterophils and lymphocytes and outer capsule of connective tissue. The fungal hyphae were hardly visible or not in HE stained sections, while septed and arborized hyphae were easily demonstrated by GMS method predominantly in central parts of granuloma. Mycological examination of feed showed the presence of Aspergillus fumigatus and Aspergillus flavus, as well as ELISA detectable level of aflatoxins (3.00 μg/kg).