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

An experimental model of haemosiderosis, using the chicken, was develo ped to examine the distribution of iron in the liver following an inje ction of iron dextran and to allow calibration of image analysis readi ngs. Image analysis was used as a tool to quantify the stainable iron present in hepatic tissue obtained from wild and captive birds present ed for necropsy. A retrospective study of 180 necropsy cases, represen ting 40 different species of bird, is described. Statistical evaluatio n of the amount and distribution of stainable iron in the liver tissue of birds from different taxonomic orders indicated that the concentra tion of iron measured in liver tissue was significantly different in d ifferent 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 diseas e, it is often associated with concurrent malignant and infectious dis eases. The presence of excess stainable iron in the liver is probably a reflection of an altered iron metabolism associated with increased t urnover of tissue iron. This alteration may occur following starvation or trauma.