c.1) Necropsy and Histopathological Examinations
After necropsy of the pigeons, collected systemic tissue samples were fixed in 10% neutral formalin (pH 7.4) and processed according to routine tissue processing procedures (Leica TP1020). After embedding in paraffin wax, tissue sections were cut at 5 μm thickness from paraffin blocks and stained with Haematoxylin-Eosin (H&E) (Luna, 1968). The histopathological changes of the lesioned organs were semiquantitatively scored and their photomicrographs were taken (Olympus BX51, DP25 digital camera).