Based on sensitive immunohistochemical methods, the ceca of three owl species (
Tyto alba,
Strix aluco,
Asio otus) were studied for the presence of important Ca-transport proteins [Ca-channel (α2-subunit), calbindin D-28K, vitamin D
3 receptor) and one mitochondrial energy marker (succinate dehydrogenase (subunit A)]. Additionally, some information is given
on basic ceca morphology, general histology, and goblet cells. The results obtained demonstrated that the enterocytes of the
ceca are regularly involved in calcium transport and that this phenomenon is generally associated with high energy demands.
The positive reactions for Ca-transport proteins were normally located in the apical cell membrane and/or cytoplasm but sometimes
also in the basal cell membrane of the enterocytes. In the crypts, this cell type generally reacted weaker for the Ca-transport
markers than in the epithelial layer of the intestinal villi; however, there were no differences between the cecal localizations
(basis, corpus, apex) studied.
Keywords Owls - Calcium transport - Ceca - Enterocytes
Communicated by W. Lutz