Histologic comparison of hepatic iron overload in managed care and free-ranging Egyptian rousette bats ( Rousettus aegyptiacus )

Abstract

Iron overload is a leading cause of morbidity and mortality in Egyptian rousette bats (ERBs; Rousettus aegyptiacus) within managed care settings. We compared hepatic iron accumulation and tissue damage in samples collected from managed care bats in a zoo setting, a research colony, and a free-ranging population with the goal of determining if iron overload was a potential cause of morbidity for free-ranging ERBs. Livers from 20 zoo bats, 8 research colony bats, and 69 free-ranging bats were histologically evaluated for fibrosis, necrosis, and iron accumulation in hepatocytes and Kupffer cells. Hemochromatosis was identified only in the zoo population, with hemosiderosis identified in all research colony bats and many free-ranging bats. There were statistically significant associations between age classification, population, and diagnosis and between Marburg virus infection status and histologic liver iron scores. In addition, there were positive associations with statistical significance between age class (juvenile, adult) and histologic iron scores and between population type (zoo bats > research colony bats > free-ranging bats) and histologic iron scores. Excessive hepatic iron storage does not appear to be a source of morbidity within free-ranging ERB populations.