Histopathological investigation of gastrointestinal system parasites in storks: Cathaemasia hians

Intestinal parasites are commonly reported in free-ranging birds and play an important role in maintaining a healthy and balanced ecosystem and causing zoonotic diseases. The aim of this work was to reveal the presence and histological findings of digestive system parasites in storks, as well as the histopathological changes caused by C. hians isolated from storks. A total of four storks, an adult black stork and three adult white storks that were brought to the pathology laboratory were used in the study. Histopathological findings of the intestines of black and white storks were determined using hematoxylin and eosin staining. During necropsy, numerous nodules were observed in the serosa of the intestines of black stork. A parasitic infection was only observed along the oesophagus. Histopathologically, in the intestines of the black stork, degeneration, necrosis and desquamation, heterophil and mononuclear cell infiltrations, parasite sections and parasite eggs, ulcerated areas, and regeneration with fibrosis were detected. Histopathologically, no parasitic infections were found in the white storks' oesophagus or proventriculus. Degeneration, necrosis, and desquamation were observed in the intestinal epithelium of white storks. This study was the first to define histopathological changes in the intestines of storks and showed severe nodular inflammation caused by C. hians in Türkiye.