Excessive iron storage in captive omnivores? The case of the coati (Nasua spp.)

We collated necropsy reports for 13 coatis (Nasua spp.), revealing four cases of moderate and six cases of massive iron deposition in liver tissue. This survey corroborates an earlier report that noted a high frequency of iron deposits in coatis at necropsy. A comparison of the reported natural diet of coatis and the usually fed captive diets revealed that whereas vertebrate products (dog/cat food, prey items) represent the staple diet items for captive individuals, free-ranging coatis only rarely consume vertebrate prey; their natural diet is dominated by wild fruits and invertebrates. This discrepancy should be reflected in high levels of readily available heme iron in captive diets, with little or no heme iron in the natural diets. Therefore, it could be hypothesized that the use of vertebrate products in animals not adapted to such high levels of readily available heme iron could be a cause for dietary iron overload. Further studies on the relevance of excessive iron storage in omnivores/insectivores, and their etiopathology, are indicated.