A QUANTITATIVE ASSESSMENT OF HEMOSIDEROSIS IN WILD AND CAPTIVE BIRDS USING IMAGE-ANALYSIS

An experimental model of haemosiderosis, using the chicken, was developed to examine the distribution of iron in the liver following an injection of iron dextran and to allow calibration of image analysis readings. Image analysis was used as a tool to quantify the stainable iron present in hepatic tissue obtained from wild and captive birds presented for necropsy. A retrospective study of 180 necropsy cases, representing 40 different species of bird, is described. Statistical evaluation of the amount and distribution of stainable iron in the liver tissue of birds from different taxonomic orders indicated that the concentration of iron measured in liver tissue was significantly different in different species of bird. The results of the study showed that hepatic haemosiderosis is a common histological finding in most avian species examined. Although not necessarily associated with overt liver disease, it is often associated with concurrent malignant and infectious diseases. The presence of excess stainable iron in the liver is probably a reflection of an altered iron metabolism associated with increased turnover of tissue iron. This alteration may occur following starvation or trauma.