Indeed, the amount of time under managed care correlated with iron accumulation in BR. Based on consistently elevated iron biomarkers and virtually every necropsy in BR under managed care in the past 60 years indicating moderate to massive iron deposition in multiple organs, BR are susceptible to excessive accumulation of iron. Furthermore, a predisposition to iron overload in BR may be due to genetic mutations affecting iron regulation and red blood cell (RBC) fragility. Under managed care, BR consume more iron than would be available in the wild, and we cannot duplicate the complexity of African browse species, including chemical properties such as iron-binding capacity. Additionally, there are possible genetic and physiological factors. The generally accepted etiology of IOD in BR is that the natural environment and diet of this browser species cannot be replicated. Why and How Do We Know BR Have Problems Accumulating Iron?īR under human care are inevitably housed differently than their wild counterparts, which impacts homeostasis (i.e., physiological regulation and stability) through diet, environment, and management of social and behavioral interactions. This report also integrates evidence from human medicine ( Figure 1), as iron overload is a common clinical problem, and the management of the disorder has been studied extensively thus, we use these learnings to supplement our strategies in BR under human care.ġ.1. Strategies and recommendations build on the collective expertise of colleagues and empirical data from experiences in BR nutrition, clinical veterinary medicine, husbandry, and operant conditioning. Specifically, as representatives of the Center for the Study of Iron in Rhinos (CSI-R), the authors will provide specific practical recommendations to treat this disorder in BR. The aim of this report is to highlight accumulated evidence supporting the successful management of this disorder to ensure optimal animal health, welfare, and longevity. IOD is a multi-factorial disease process requiring an evidence-based and integrative approach for successful prevention and treatment. A lack of acute clinical symptoms in this species is not an honest marker of animal health nor iron balance. BR can live many years with IOD and typically do not show overt signs of illness until late in disease progression resulting in a shortened life span and reduced fecundity in this endangered species. Iron overload is an abnormal and chronic imbalance of iron metabolism with iron accumulation occurring over the course of years, saturating iron transport proteins and leading to organ damage and failure (reviewed in ). Over the last 30 years, BR have been documented with diseases that have either been induced by or exacerbated by IOD, prompting significant efforts in diagnostic, treatment, and prevention strategies. Poaching has reduced the wild population by >90% since 1970, and ~240 individuals are managed under human care with ~87 individuals in North America. BR are native to eastern and central Africa and are Critically Endangered. The aim is to use evidence to support the successful management of this disorder to ensure optimal animal health, welfare, and longevity for a sustainable black rhinoceros population.īlack rhinoceroses (BR Diceros bicornis) under human care are predisposed to non-hemochromatosis Iron Overload Disorder (IOD see Section 1.3 How does IOD work in BR?) with laboratory and histopathologic evidence of cellular injury, necrosis, and clinical signs similar to human iron overload disorders. This report includes sections on (1) background on how iron functions in comparative species and how Iron Overload Disorder appears to work in black rhinos, (2) practical recommendations for known diagnostics, (3) a brief review of current investigations on inflammatory and other potential biomarkers, (4) nutrition knowledge and advice as prevention, and (5) an overview of treatment options including information on chelation and details on performing large volume voluntary phlebotomy.
We aim to address the black rhino caretaker community at multiple perspectives (keeper, curator, veterinarian, nutritionist, veterinary technician, and researcher) to describe approaches to Iron Overload Disorder in black rhinos and share learnings. Black rhinoceros under human care are predisposed to Iron Overload Disorder that is unlike the hereditary condition seen in humans.