HISTOLOGICAL ANALYSIS OF THE INTESTINAL TRACT OF Caracara plancus (Miller, 1777)

Abstract The Southern Crested Carcara is a bird with a recognized ecological role in the population control of small birds and mammals, feeding on live prey as much as on decaying animals. The objective of this study was to analyze the histology of Carcara`s intestinal tract of five Carcaras from the Wild Animal Screening Center of Pernambuco were euthanized to remove their intestines and cloacae. The tissues were stained with Hematoxylin/Eosin, Alcian Blue pH 1.0, and Periodic Acid Schiff. The villi of the small and large intestines are lined with a simple columnar epithelium with microvilli membranes and goblet cells. The lamina contains lymphocytes and form lymphatic follicles within some of the villi. The mucosal muscle is arranged in a longitudinal direction. The submucosal layer was only observed in the cloaca and the muscle layer has transverse and longitudinal fibers. The serous membrane lines the whole intestinal tract and is composed of mesothelium and submesothelial connective tissue. Longitudinal folds were found in the large intestine. The conclusion is that the Carcara`s intestine exhibits an overall structure compatible with the histological pattern observed in other species of birds; however, Paneth cells and the submucosal layer were not observed. Lymph follicles were found inside the villi and a high number of goblet cells at the end of the ileum and large intestine.