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Intravascular hemolysis releases hemoglobin (Hb) from red blood cells under specific conditions, yet the effect of hemolysis in aquaculture systems remain poorly understood. In this study, a continuous hemolysis model for grass carp was established by injection of phenylhydrazine (PHZ) to investigate the mechanistic impacts of sustained hemolysis. PHZ-induced hemolysis altered liver color, and subsequent hematoxylin and eosin staining revealed substantial Hb accumulation in the head kidney, accompanied by inflammatory cell infiltration and vacuolization in liver tissue. Quantitative real-time PCR and western blotting confirmed that PHZ treatment significantly upregulated Real-time fluorescence quantitative PCR and Western blot confirmed that PHZ treatment significantly up-regulated the expression of iron metabolism-related genes and proteins, including transferrin (Tf), ferritin, ferroportin 1 (FPN1), transferrin receptor 1 (TfR1), nuclear receptor coactivator 4 (NCOA4), divalent metal transporter 1 (DMT1), and six-transmembrane epithelial antigen of prostate 3 (STEAP3). Further investigation of PHZ-induced hemolysis effects on tissues showed that inflammation- and antioxidant enzyme-related genes in the liver and head kidney were significantly upregulated, indicating that hemolysis activated the antioxidant system and intensified inflammatory responses. Perls' staining revealed iron deposition in the head kidney and liver at ten and fourteen days post-PHZ injection. Moreover, β-galactosidase staining and transmission electron microscopy showed increased cellular senescence and mitochondrial damage, respectively, as a result of PHZ-induced hemolysis. In vitro assays with hemin treatment demonstrated increased Fe2+ content in CIK and L8824 cells, which induced oxidative stress, upregulated iron metabolism and inflammatory genes, and ultimately led to cell death. These findings suggest that excessive Hb release during sustained hemolysis leads to iron overload, elevates reactive oxygen species production, disrupts antioxidant balance, and ultimately causes cellular damage., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024. Published by Elsevier Ltd.)

Importance: Hemochromatosis is rare in domestic animals, and iron-induced myopathy has not been reported in veterinary medicine. This case is the first report of iron-overload myopathy owing to hemochromatosis in a dog., Case Presentation: A 9-year-old spayed female Donggyeong dog presented with severe forelimb lameness. Necropsy revealed an enlarged liver and hemorrhagic lesions in the forelimb muscle. Microscopy showed iron components accumulation in multiple organs, including the liver, forelimb skeletal muscle, spleen, lymph node, and kidney. Prussian blue staining identified iron deposits in both macrophages and parenchymal cells, indicating that the iron accumulation was acquired rather than hereditary. Furthermore, iron components were observed within muscle fibers, accompanied by severe atrophy and myositis., Conclusions and Relevance: Severe necrosis and mild fibrosis were observed in the liver and forelimb skeletal muscles. Based on histological analysis, we diagnosed iron overload myopathy by secondary hemochromatosis. Secondary hemochromatosis with severe muscle atrophy and myositis is very rare, and this is the first report of iron-overload myopathy in a dog., Competing Interests: The authors declare no conflicts of interest., (© 2025 The Korean Society of Veterinary Science.)

While iron overload disorder (IOD) and related disease states are not considered a common occurrence in domestic equids, these issues appear prevalent in black rhinoceroses under human care. In addressing IOD in black rhinos, altering dietary iron absorption and excretion may be the most globally practical approach. A main option for treatment used across other species such as humans, is chelation therapy using iron-specific synthetic compounds. As horses may serve as an appropriate digestive model for the endangered rhinoceros, we evaluated the potential use of the oral iron chelator N,N-bis(2-hydroxybenzyl)ethylenediamine-N,N-diacetic acid (HBED) in horses for safety and efficacy prior to testing in black rhinoceros. Health and iron digestibility and dynamics were assessed in horses (n = 6) before, and after treatment with HBED (50 mg/kg body weight) for 8 days using a crossover design with serum, faecal and urine collection. A preliminary pharmacokinetic trial was also performed but no trace of HBED was found in serially sampled plasma through 8 h post-oral dosing. HBED increased urinary iron output in horses compared to control by 0.7% of total iron intake (p < 0.01), for an average of 27 mg urinary iron/day, similar to human chelation goals. Blood chemistry, blood cell counts and overall wellness were not affected by treatment. As healthy horses are able to regulate iron absorption, the lack of change in iron balance is unsurprising. Short-term HBED administration appeared to be safely tolerated by horses, therefore it was anticipated it would also be safe to administer to black rhinos for the management of iron overload., (© 2022 The Authors. Journal of Animal Physiology and Animal Nutrition published by Wiley-VCH GmbH.)

The current treatments applied in aquaculture to limit disease dissemination are mostly based on the use of antibiotics, either as prophylactic or therapeutic agents, with vaccines being available for a limited number of fish species and pathogens. Antimicrobial peptides are considered as promising novel substances to be used in aquaculture, due to their antimicrobial and immunomodulatory activities. Hepcidin, the major iron metabolism regulator, is found as a single gene in most mammals, but in certain fish species, including the European sea bass ( Dicentrarchus labrax ), two different hepcidin types are found, with specialized roles: the single type 1 hepcidin is involved in iron homeostasis trough the regulation of ferroportin, the only known iron exporter; and the various type 2 hepcidins present antimicrobial activity against a number of different pathogens. In this study, we tested the administration of sea bass derived hepcidins in models of infection and iron overload. Administration with hamp2 substantially reduced fish mortalities and bacterial loads, presenting itself as a viable alternative to the use of antibiotics. On the other hand, hamp1 seems to attenuate the effects of iron overload. Further studies are necessary to test the potential protective effects of hamp2 against other pathogens, as well as to understand how hamp2 stimulate the inflammatory responses, leading to an increased fish survival upon infection., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Barroso, Carvalho, Nunes, Gonçalves, Rodrigues and Neves.)

Iron plays an essential role in preventing iron deficiency anemia and ensuring the healthy growth of animals. The special physiological condition of piglets is the main cause of iron deficiency. Iron metabolism in the intestine is the basis for understanding the effects of iron on the health of piglets. In order to scientifically evaluate dietary iron supplementation doses, it is necessary to recognize the effects of iron deficiency and iron overload on piglet intestinal health. Besides, iron as a cofactor is essential for the growth of microorganisms, and microorganisms compete with the host to absorb iron. Under the stress of iron deficiency and iron overload, various control schemes (such as precise nutrition, element balance, elimination of oxidation, etc.) are effective measures to eliminate adverse effects. In this review, we comprehensively review recent findings on the effects of iron deficiency and iron overload on intestinal health. This review will provide a rational design strategy to achieve a reasonable iron supplement, which will guide the use of iron in animal husbandry.

Background: Hyperinsulinemia associated with equine metabolic syndrome and pituitary pars intermedia dysfunction is a risk factor for laminitis. Research in other species has shown elevated body iron levels as both a predictor and consequence of insulin resistance. In humans, this is known as dysmetabolic hyperferritinemia., Aim: To explore the relationship between equine hyperinsulinemia and body iron levels., Methods: We reviewed case histories and laboratory results from an open access database maintained by the Equine Cushing's and Insulin Resistance Group Inc. (ECIR). We identified 33 horses with confirmed hyperinsulinemia and laboratory results for serum iron, total iron binding capacity, and ferritin. Pearson correlation was used to test the relationship between insulin and iron indices. Additionally, we performed a secondary analysis of a previously reported controlled trial that was originally designed to test the correlation between iron status and the insulin response in horses. Here, we used a t -test to compare the mean values of insulin and ferritin between horses we categorized as normal or hyperinsulinemic based on their response to an oral challenge., Results: Serum ferritin exceeded published reference range in 100% of the horses identified from the ECIR database. There were no statistically significant associations between insulin indices (RISQI, log insulin) and iron indices (log serum iron, log TSI%, log ferritin). There were trends for a negative association between RISQI and log iron [ r (31) = -0.33, p = 0.058] and a positive association between age and ferritin [ r (30) = 0.34, p = 0.054]. From the secondary data analysis of published data, we found significantly elevated ferritin ( p = 0.05) in horses considered hyperinsulinemic by dynamic insulin testing compared to horses with a normal response., Conclusion: These results suggest the potential for iron overload in hyperinsulinemic horses, a feature documented in other species and should stimulate further study into the relationship between insulin and iron dysregulation in the horse.

Background: Iron toxicosis is rarely reported in horses and chronic excessive oral iron intake has not been reported to cause clinical symptoms in equids., Objectives: This case series describes 21 genetically unrelated horses and one donkey with chronic iron overload causing haemochromatosis and hepatopathy., Study Design: Case series., Methods: All equids showing clinical signs compatible with chronic liver disease presented to Utrecht University and diagnosed with iron overload and haemochromatosis based on histopathological evaluation of liver tissue and/or blood transferrin saturation levels of >80% and proof of excess dietary iron intake due to excess iron content in drinking water were included., Results: This study included 22 equids. All tested animals (n = 19) had transferrin saturation >80% and 21 of 22 had increased gamma-glutamyltransferase (γGT). Ultrasonography revealed rounded liver margins in five out of six horses and increased echogenicity in 4/6. Histological examination of liver tissue of 12 animals showed hepatitis, fibrosis and haemosiderin accumulation in macrophages and hepatocytes. Post-mortem examination also revealed haemosiderin accumulation in other organs in all seven examined animals. High iron content in drinking water was identified as the source of iron overload in all cases. All animals were housed under the same conditions for a minimum of 9 years prior to diagnosis of haemochromatosis. Of 22 animals, 13 survived until 1 January 2018, ranging from 17 to 79 months post diagnosis., Main Limitations: Histology of liver tissue was not available for 10 of 22 cases., Conclusions: Chronic iron overload can lead to haemochromatosis and hepatopathy in equids. Development of disease is slow and clinical signs are nonspecific. Long-term excessive iron intake in equids should be avoided. If animals drink from natural water sources, it is important to test the water for iron content. The Summary is available in Spanish - see Supporting Information., (© 2018 EVJ Ltd.)

Background: Iron oversupplementation in healthy term infants may adversely affect growth and cognitive development., Objective: We hypothesized that early-life iron excess causes systemic and central nervous system iron overload, and compromises social behavior., Methods: The nursing pig was used as a translational model in a completely randomized study. On postnatal day (PD) 1, 24 pigs (1.57 ± 0.28 kg mean ± standard deviation body wt) were assigned to the following treatment groups: 1) nonsupplemented iron-deficient group (NON); 2) control group (CON), intramuscularly injected with iron dextran (100 mg Fe) on PD2; 3) moderate iron group (MOD), orally administered ferrous sulfate at 10 mg Fe · kg body wt-1 · d-1; and 4) high iron group (HIG), orally administered ferrous sulfate at 50 mg Fe · kg-1 · d-1. Piglets were nursed by sows during the study from PD1 to PD21. Tissue iron was analyzed by atomic absorption spectrophotometry. Messenger RNA and protein expression of iron regulator and transporters were analyzed by quantitative reverse transcriptase-polymerase chain reaction and Western blot. A sociability test was performed on PD19-20., Results: Both MOD and HIG treatments (5.51 and 9.85 µmol/g tissue), but not CON (0.54 µmol/g), increased hepatic iron as compared with NON (0.25 µmol/g, P < 0.05). Similarly, the hippocampal iron concentrations in the MOD and HIG groups were 14.9% and 31.8% higher than that of NON, respectively (P < 0.05). In comparison with NON, MOD and HIG treatment repressed DMT1 in duodenal mucosa by 4- and 46-fold, respectively (P < 0.05); HIG drastically induced HAMP in liver by 540-fold (P < 0.05); iron-supplemented groups reduced TFRC in the hippocampus by <1-fold (P < 0.05). However, duodenal expression of ferroportin, the predominant transporter in basal membrane, was not affected by treatment. Despite normal sociability, the MOD and HIG pigs displayed deficits in social novelty recognition (P = 0.004)., Conclusions: Duodenal ferroportin was hyporesponsive to iron excess (MOD and HIG), which caused hippocampal iron overload and impaired social novelty recognition in nursing pigs., (© 2019 American Society for Nutrition.)

Background and Objective: Iron is an essential element that involved in many vital physiological functions in fish, while excess iron concentration causes many toxic effects. Curcumin is a natural popular spice that used as a dietary supplementation and has iron chelating properties. This study was conducted to evaluate the effect of curcumin on iron toxicity in catfish (Clarias gariepinus). Also this study assess the antibacterial effect of curcumin against Vibrio anguillarum infection., Materials and Methods: Clarias gariepinus were orally exposed to low and high doses of curcumin (40, 80 mg kg-1 fish) for 3 weeks. Fish were then exposed to 25 mg L-1 of ferric chloride as a source of iron toxicity for another 3 weeks. Some hematological parameters (Total and differential white blood cells count, total red blood cells count, hemoglobin concentration and hematocrit %) and biochemical parameters (Serum ferritin, transferrin, ALT, AST, protein and albumin) were assessed before and after exposure to iron. Iron residues in gills, spleen, liver, kidney, abdominal fats, gonads and muscles were also determined. Moreover the determination of fish survivability after bacterial challenge with Vibrio anguillarum was recorded., Results: Iron caused decrease in total white blood cells count (WBCs), increase in ferritin level and elevation in liver function enzymes (ALT and AST). However, the pretreatment of fish with curcumin significantly increased WBCs, lymphocyte percentage, ferritin level and protein and albumin concentrations with significantly decreased transferrin, ALT and AST levels. Also there were significant decreases in iron concentration in serum, kidney, gonads and muscle in both low and high curcumin pretreated groups compared to Fe group., Conclusion: Results indicated a modulatory effect of curcumin against iron toxicity in catfish, also curcumin had an immune-stimulant effect against Vibrio anguillarum infection.

Iron overload has been described in various wild species. The majority of cases involve captive animals, often associated with increased dietary iron uptake. Here a case of idiopathic iron overload in a female adult harbor seal under human care is presented. The animal displayed a progressive anorexia, apathy, and increased serum iron levels. Radiographs showed radiopaque foreign bodies in the stomach. The seal died during an elective laparotomy. Twenty-five coins and two metal rings were removed from the stomach. Histopathologic examination revealed iron storage without cellular damage in liver, spleen, kidney, and pulmonary and mesenteric lymph nodes. Atomic absorption spectrophotometry analysis for iron revealed values thirty times above the reference ranges in spleen and liver; however, the coins only contain minor levels (parts per million) of iron. The etiology of the iron overload in this animal remains unclear. A multifactorial process cannot be excluded.

Iron though an essential cofactor for many proteins including haemoglobin and cytochromes, when in excess (>1 ppm in water and 100 ppm in fish tissue) elicits toxicity via Fenton reaction inducing oxidative stress. The present study aimed to evaluate the efficacy of dietary Spirulina (Arthrospira platensis) supplementation on waterborne-iron induced oxidative stress in the tissues of Notopterus notopterus. Juvenile fishes were divided randomly into 4 groups, namely, Group-I: control fed with commercial diet only, Group-II, III and IV treated with 0.75 ppm FeCl 3 where Group-II fed with commercial diet only, Group-III with 10% (w/w) Spirulina supplemented commercial diet and Group-IV with 100% (w/w) Spirulina diet only; for 7 and 28 days (n = 6 per group). Tissue oxidative stress biomarkers like lipid peroxidation (LPx), protein carbonylation (PC) and protein thionylation (protein and nonprotein-SH content); antioxidant defence (superoxide dismutase: SOD; catalase; CAT; glutathione peroxidase/reductase: GPx/GR; glutathione s-transferase: GST; metalothionine: MT and reduced glutathione: GSH) and iron accumulation in the gill, liver and muscles tissue were analysed. The augmented oxidative predominance in the tissues with respect to LPx and PC along with decline in antioxidant defence (SOD, CAT, GPx, GR, GST, MT, PSH, NPSH and GSH) by iron was neutralized by Spirulina supplementation in the diet in a dose and duration dependent manner where 100% Spirulina diet for 28 days completely ameliorated iron-induced oxidative stress in fish tissues. Thus, Spirulina can be used as a dietary supplement for fishes cultured in water bodies with iron overload., (Copyright © 2018. Published by Elsevier B.V.)

Iron overload disorder (IOD) can lead to organ dysfunction and may exacerbate other diseases in the critically endangered black rhinoceros ( Diceros bicornis). It is important to develop methods for monitoring the progression of iron storage (hemosiderosis), diagnosing the disease, and evaluating treatments in this species. Traditionally, an equine enzyme immunoassay (EIA) was used to measure rhinoceros ferritin, a serum protein correlated to iron stores. The goal of this study was to validate a rhinoceros-specific assay and investigate factors potentially associated with ferritin concentrations in black rhinoceros. A ferritin EIA developed for Sumatran rhinoceros was validated for black rhinoceros via Western blot analysis of liver ferritin and confirmed parallelism of serum samples to the EIA standard curve and used to analyze serum samples ( n = 943) collected from 36 black rhinoceros (<1-33 yr) at 14 U.S. institutions. Mean (±SEM) serum ferritin concentration was 6,738 ± 518 ng/ml (range: 85-168,451 ng/ml). Concentrations differed among individuals with eastern black rhinoceros (7,444 ± 1,130 ng/ml) having a higher mean ferritin than southern black rhinoceros (6,317 ± 505 ng/ml; P < 0.05) and higher mean values in wild-born (11,110 ± 1,111 ng/ml) than captive-born individuals (3,487 ± 293 ng/ml; P < 0.05). Ferritin concentrations did not differ between young rhinoceros (<5 yr old; 2,163 ± 254 ng/ml) and adults (7,623 ± 610 ng/ml) and were not correlated with age ( r = 0.143) or time in captivity ( r = 0.146, wild born; r = 0.104, all animals). Ferritin concentration was not impacted by sex (female: 2,086 ± 190 ng/ml; male: 8,684 ± 717 ng/ml), date, month, or season of collection ( P > 0.05). Data indicate ferritin concentrations are variable and not necessarily associated with IOD; ferritin is not recommended for diagnosing or monitoring IOD in black rhinoceros.

The aim of this study was to determine if ferritin is a reliable biomarker of iron overload disorder (IOD) progression and hemochromatosis in the Sumatran rhinoceros (Dicerorhinus sumatrensis) by developing a species-specific ferritin assay and testing historically banked samples collected from rhinos that did and did not die of hemochromatosis. Ferritin extracted from Sumatran rhino liver tissue was used to generate antibodies for the Enzyme Immunoassay. Historically banked Sumatran rhino serum samples (n = 298) obtained from six rhinos in US zoos (n = 290); five rhinos at the Sumatran Rhino Conservation Centre in Sungai Dusun, Malaysia (n = 5); and two rhinos in Sabah, Malaysia (n = 3) were analyzed for ferritin concentrations. Across all US zoo samples, serum ferritin concentrations ranged from 348 to 7,071 ng/ml, with individual means ranging from 1,267 (n = 25) to 2,604 ng/ml (n = 36). The ferritin profiles were dynamic, and all rhinos exhibited spikes in ferritin above baseline during the sampling period. The rhino with the highest mean ferritin concentration did not die of hemochromatosis and exhibited only mild hemosiderosis postmortem. A reproductive female exhibited decreases and increases in serum ferritin concurrent with pregnant and nonpregnant states, respectively. Mean (±SD) serum ferritin concentration for Sumatran rhinos in Malaysia was high (4,904 ± 4,828 ng/ml) compared to that for US zoo rhinos (1,835 ± 495 ng/ml). However, those in Sabah had lower ferritin concentrations (1,025 ± 52.7 ng/ml) compared to those in Sungai Dusun (6,456 ± 4,941 ng/ml). In conclusion, Sumatran rhino serum ferritin concentrations are dynamic, and increases often are not associated with illness or hemochromatosis. Neither a specific pattern nor the individual's overall mean ferritin concentration can be used to accurately assess IOD progression or diagnose hemochromatosis in this rhino species.

Iron overload disorder (IOD) is a significant health issue for captive black rhinoceros ( Diceros bicornis ). Measurement of serum ferritin with a validated rhinoceros ferritin ELISA has been used extensively to detect animals in U.S. zoos that are at risk of developing IOD. However, there is limited information on serum ferritin levels in free-ranging black rhinoceros using this same assay. Serum ferritin, iron, and gamma-glutamyl transpeptidase (GGT) were determined in 194 black rhinoceros from southern Africa. Mean ferritin in free-ranging black rhinoceros (290.54 ±247.4 ng/ml) was significantly higher than in free-ranging white rhinoceros (64.0 ± 102.4 ng/ml) sampled in this study from Kruger National Park, South Africa. However, there were no significant differences between genders or age groups. Ferritin values varied with geographical location of the black rhinoceros, although this was not clinically significant. Serum iron values were also higher in black rhinoceros (40.4 ± 19.1 μmol/L) compared to white rhinoceros (29.7 ± 10.7 μmol/L). There was no association between ferritin and GGT. This study provides serum ferritin, iron, and GGT values from free-ranging black rhinoceros that can be used for as comparative target values for captive animals.

The African black rhinoceros (Diceros bicornis) has adapted to a low iron diet during evolution and is thus prone to iron overload in captivity, which is associated with a number of serious disorders. A S88T polymorphism in the HFE gene has been suggested as a potential genetic basis of increased iron uptake in the black rhinoceros, while the Indian rhinoceros is thought to be unaffected by iron overload in captivity. In the present study, the histopathology and distribution of iron accumulations in five black rhinoceroses with iron overload syndrome were characterized and compared with three Indian rhinoceroses (Rhinoceros unicornis) and one African white rhinoceros (Ceratotherium simum). At necropsy examination, iron storage in black rhinoceroses was not associated with gross lesions. Microscopically, the most consistent and highest degree of iron load was found in the spleen, liver, small intestine and lung. There was minimal fibrosis and single cell necrosis in the liver. Endocrine organs, lymph nodes, heart and kidney were less often and less markedly affected. Unexpectedly, Indian rhinoceroses also showed iron load in the spleen and smaller amounts in organs similar to the black rhinoceros except for in the heart, while the white rhinoceros had only minor detectable iron storage in intestine, liver and lung. Sequence analysis confirmed the HFE S88T polymorphism in black but not in Indian rhinoceroses. The results indicate that Indian rhinoceroses may also be affected by iron storage in captivity, although in a milder form than the black rhinoceros, and therefore challenge the relevance of the S88T polymorphism in the HFE gene of black rhinoceroses as the underlying cause for iron overload., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Iron overload disorder afflicts captive rhinoceros but has not been documented in the wild. The specific cause for the disorder has not been identified but is likely associated with diet and management. Compared with wild counterparts, captive rhinoceros eat diets containing more iron, have greater fat stores, and exercise less. It has been suggested that the problem may be linked to development of insulin resistance in the captive population. Given that controlled experiments with sufficient numbers of rhinoceros are logistically not possible, an equine model was used to look for a relationship between iron status and insulin resistance; the nutritional requirements of horses are used as a guide for rhinoceros, because they have similar gastrointestinal tracts. Sixteen horses were tested to determine blood insulin responses to an oral drench of dextrose (0.25 g/kg bodyweight) and a meal of pelleted corn (1.5 g/kg bodyweight). Fasting blood samples were taken 30 and 0 min before administration. Further blood samples were taken every 30 min for 4 hr after administration to determine peak insulin and total area under the insulin curve (AUC). Fasting samples were tested for serum ferritin concentrations. Correlations were determined between ferritin and peak insulin concentrations and insulin AUC after administration of oral dextrose and pelleted corn. The strongest correlation was between ferritin and insulin AUC after dextrose administration (r = 0.61; P = 0.01) followed by AUC after feeding a meal of pelleted corn (r = 0.60; P = 0.01), with the correlation for peak insulin being 0.53 (P = 0.03) after dextrose administration and 0.56 (P = 0.02) after pelleted corn. When evaluating responses by gender, a significant correlation existed only for females, influenced by one insulin resistant individual. These data suggest a potential link between insulin resistance and body stores of iron and also suggest that approaches to reduce the susceptibility to insulin resistance should be incorporated into management of captive browsing rhinoceros.

Case Description: 3 hornbills (2 Papua hornbills [Aceros plicatus] and 1 longtailed hornbill [Tockus albocristatus]) were evaluated because of general listlessness and loss of feather glossiness., Clinical Findings: Because hepatic iron storage disease was suspected, liver biopsy was performed and formalin-fixed liver samples were submitted for histologic examination and quantitative image analysis (QIA). Additional frozen liver samples were submitted for chemical analysis. Birds also underwent magnetic resonance imaging (MRI) under general anesthesia for noninvasive measurement of liver iron content. Serum biochemical analysis and analysis of feed were also performed. Results of diagnostic testing indicated that all 3 hornbills were affected with hepatic iron storage disease., Treatment and Outcome: The iron chelator deferiprone was administered (75 mg/kg [34.1 mg/lb], PO, once daily for 90 days). During the treatment period, liver biopsy samples were obtained at regular intervals for QIA and chemical analysis of the liver iron content and follow-up MRI was performed. In all 3 hornbills, a rapid and large decrease in liver iron content was observed. All 3 methods for quantifying the liver iron content were able to verify the decrease in liver iron content., Clinical Relevance: Orally administered deferiprone was found to effectively reduce the liver iron content in these 3 hornbills with iron storage disease. All 3 methods used to monitor the liver iron content (QIA, chemical analysis of liver biopsy samples, and MRI) had similar results, indicating that all of these methods should be considered for the diagnosis of iron storage disease and monitoring of liver iron content during treatment.

Iron is an essential element for nearly all living organisms and disruption of iron homeostasis can lead to a number of clinical manifestations. Iron is used in the formation of both hemoglobin and myoglobin, as well as numerous enzyme systems of the body. Disorders of iron in the body include iron deficiency anemia, anemia of inflammatory disease, and iron overload. This article reviews normal iron metabolism, disease syndromes of iron imbalance, diagnostic testing, and treatment of either iron deficiency or excess. Recent advances in diagnosing iron deficiency using reticulocyte indices are reviewed.

Case Description: 3 adult (24- to 43-year-old) Atlantic bottlenose dolphins (Tursiops truncatus) with chronic episodic malaise and inappetence associated with high serum aminotransferase (alanine aminotransferase and aspartate aminotransferase) activities, high serum iron concentration, and serum transferrin saturation > 80% were evaluated., Clinical Findings: Results of histologic examination of liver biopsy specimens revealed hemosiderosis in all 3 dolphins. Except for chronic lymphocytosis in 1 dolphin, results of extensive diagnostic testing revealed no other abnormalities. For each dolphin, a diagnosis of iron overload of unknown origin was made., Treatment and Outcome: Phlebotomy treatment was implemented to reduce body stores of iron. Each phlebotomy procedure removed 7% to 17% (1 to 3 L) of estimated blood volume. Treatment consisted of an induction phase of weekly phlebotomy procedures for 22 to 30 weeks, which was complete when serum iron concentration and aminotransferase activities were within reference ranges and serum transferrin saturation was < or = 20% or Hct was < or = 30%. Total amount of iron removed from each dolphin was 53 to 111 mg/kg (24.1 to 50.5 mg/lb) of body weight. One dolphin required maintenance procedures at 8- to 12-week intervals when high serum iron concentration was detected., Clinical Relevance: Although the cause of the iron overload and high serum aminotransferase activities remained unknown, phlebotomy treatment successfully resolved the clinicopathologic abnormalities, supporting a role of iron overload in the hepatopathy of the 3 dolphins.

Hepcidin, an antimicrobial and iron-regulating peptide, is a key molecule of the innate immune system of bony fish. In this study, four isoforms of hepcidin genes were characterized from a marine Perciform fish, rockbream (Oplegnathus fasciatus), and the transcriptional modulations of these isoforms in response to different biological stimulations were also examined. All rockbream hepcidin isoform genes exhibited a tripartite structure and their promoter regions displayed typical binding motifs for the transcription factors including C/EBP, HNF, AP, NF-kbeta, GATA, USF and/or STAT. Hepcidin transcripts in juvenile or fingerling tissues were dramatically induced during experimental challenges with various bacterial species, iron overload and rockbream iridovirus infection. The transcription ofhepcidins was regulated in an isoform- and tissue-specific fashion. In addition, we identified for the first time that partially processed hepcidin transcripts were significantly elevated during bacterial infection and iron overload. Results from this study provide a good basis to better understand the isoform-specific role of hepcidin in the fish innate immune system.

Deferiprone is a bidentate oral iron chelator used for the treatment of iron overload in people. The purpose of this study was to determine the pharmacokinetic disposition of deferiprone in the domestic pigeon (Columba livia) and to compare the results with a previous study in the white leghorn chicken. Deferiprone (DFP) was administered orally as a suspension at a single dose of 50 mg/kg to 10 iron-loaded (IL-DFP) pigeons and 10 non--iron-loaded controls (NIL-DFP). Six NIL-DFP birds were also administered deferiprone intravenously to determine the bioavailability of the drug after a 30-day washout period. To evaluate if deferiprone induces its own metabolism, the pharmacokinetic disposition of the drug was also studied in the IL-DFP group after oral therapy with deferiprone at a dosage of 50 mg/kg q12h for 30 days. For each phase, collected blood was analyzed for deferiprone by high-performance liquid chromatography to develop a plasma concentration versus time curve. Deferiprone was rapidly absorbed from the gastrointestinal tract, with plasma concentrations effective for iron chelation maintained for at least 8 hours after administration in iron-loaded birds. The half-life (mean +/- SD) for deferiprone given orally to the IL-DFP and NIL-DFP groups was 2.98 +/- 0.85 hours and 3.26 +/- 1.25 hours, respectively, and when intravenously administered was 3.79 +/- 1.23 hours. The half-life after 30 days of treatment was 3.42 +/- 1.18 hours. Oral bioavailability was 44%. This study demonstrated that oral absorption of deferiprone is acceptable, it does not induce its own metabolism, and the drug was widely distributed in the pigeon, as it was in the chicken, with a longer half-life than that reported in mammals. Minor interspecies variations in the pharmacokinetics of deferiprone exist between chickens and pigeons.

Deferiprone is a bidentate oral iron chelator used for the treatment of transfusional iron overload in people. The purpose of this study was to determine the pharmacokinetic disposition of deferiprone in the white leghorn chicken as a potential model upon which to base therapeutic regimens for the treatment of iron storage disease (hemochromatosis) in affected avian species. A suspension of deferiprone (DFP) was administered orally at a single dose of 50 mg/kg to 10 birds that were iron-loaded (IL-DFP) and 10 non--iron-loaded control birds (NIL-DFP). After a 30-day washout period, 5 birds from the NIL-DFP group were used for a bioavailability study of deferiprone administered intravenously at the same dose. Blood samples were collected at varying intervals over a 24-hour period and were analyzed for deferiprone by high-performance liquid chromatography, then plasma concentration versus time curves were developed. Deferiprone was rapidly absorbed from the gastrointestinal tract of the chicken, with plasma concentrations effective for iron chelation in humans (>20 micromol/L) maintained for at least 8 hours after oral dosing. The half-life (mean +/- SD) of the orally administered deferiprone in the IL-DFP and NIL-DFP groups was 2.91 +/- 0.78 hours and 3.61 +/- 0.90 hours, respectively, and was 2.42 +/- 0.24 hours for deferiprone administered intravenously. The mean oral bioavailability was 93%. Deferiprone is well absorbed and widely distributed in the chicken, with a longer half-life than reported in mammals.

Two-year-old whitefish (Coregonus lavaretus) were exposed for 30 days to episodic iron overload in iron-rich humic water (5%) supplemented with inorganic iron (5 mg FeL(-1)). Two parallel laboratory exposures were performed, one under conditions simulating winter and the other under conditions simulating spring. After exposure, some of the fish were subjected to acute handling stress in the form of a short air challenge to reveal possible modification of the primary and secondary stress responses. In whitefish sampled without additional handling, iron accumulated in the liver (under spring conditions) and gills (under winter and spring conditions); plasma catecholamine and beta-estradiol (both winter and spring groups) as well as blood hematocrit (winter group only) levels were depressed; blood glucose (winter group only) and red blood cell (RBC) Na+ levels (spring group only) were increased. In handled whitefish, liver glycogen phosphorylase (GPase), RBC, and blood glucose stress responses were impaired by the applied exposure conditions, which reflected natural iron-rich humic water. Exposure also removed some physiological effects of the applied ambient conditions: plasma catecholamines and beta-estradiol, gill Na+/K+ -ATPase, and RBC K+ concentration were not different in two iron-exposed fish groups, whereas there was a difference in reference fish. Thus, the physiological effects of this type of subchronic exposure, together with alterations in the acute stress response, can lead to incorrect conclusions being drawn from the results, if the effects of time-dependent stress response are ignored. In conclusion, waterborne iron overload may impair the optimal capacity of whitefish to carry out their normal physiological functions such as responding to external threats.

The clinical use of oral Fe chelators for the treatment of Fe-storage disease in birds requires evaluation. In this study, the efficacy of the Fe chelator deferiprone in reducing hepatic Fe stores, its effects on hematologic, biochemical, and plasma Fe parameters, and its potential toxicity during a 30-day treatment period were investigated in a controlled setting using two model species, the white leghorn chicken (Gallus gallus f. domestica) and the domestic pigeon (Columba livia). A second phase of the study investigated deferiprone-related Fe elimination in the excreta. Deferiprone, administered orally at a dosage of 50 mg/kg twice daily to birds that had been experimentally Fe loaded, significantly reduced hepatic Fe concentrations compared with levels in Fe-loaded and non-Fe-loaded controls. There were no significant alterations in routine clinical hematologic or biochemical parameters, although decreased transferrin saturation was noted in both species. Side effects associated with deferiprone administration were decreased weight gain and significant decreases in plasma Zn concentrations. No mortalities occurred in the pigeons, but there were three deaths in the deferiprone-treated group of Fe-loaded chickens, most likely associated with acute reduction of Fe required for normal enzymatic processes. Histologic changes associated with deferiprone treatment were not noted. Deferiprone caused a dose-dependent increase of Fe in the excreta at oral dosages of 50 and 75 mg/kg once daily in both species. Deferiprone is a promising, orally active Fe chelator for the treatment of Fe overload in birds, although its potential side effects need to be considered.

Iron overload is a very frequent finding in several animal species and a genetic predisposition is suggested. In one of the most commonly reported species with susceptibility for iron overload (mynah bird), it was recently shown that the cause of this pathophysiology is high uptake and retention of dietary iron. Here we compare susceptible (mynahs) with non-susceptible avian species (chickens) by evaluating iron uptake at the intestinal absorptive cell level. Enterocytes from mynahs and chickens were isolated and uptake of Fe(II) and Fe(III) was studied in vitro. It was found that Fe(III) uptake is much lower than Fe(II) uptake for both species. Although liver iron, present only in hepatocytes, was at least 10-fold higher in mynahs than chickens, enterocyte Fe(II) uptake was considerably higher in mynahs. Fe(II) uptake showed saturation at the studied concentrations in both species. Kinetic studies revealed a three-fold increase in Vmax for mynahs. Calculated values for the uptake kinetics of the probable membrane transporter suggest that mynah bird enterocytes have a significantly higher limiting uptake rate, due to the possible increase in the number of transporters when compared with chicken enterocytes. The susceptibility of this species is due to intestinal iron uptake despite hepatic iron accumulation, implicating a 'mis-sensing' of body iron similarly to human hereditary haemochromatosis.

Objective: To investigate the possibility that excessive maternal iron (overload) may contribute to development of congenital leukoencephalomalacia in captive black rhinoceroses., Sample Population: Tissue specimens and serum samples from 18 rhinoceroses in 2 kindreds harboring 4 (possibly 5) affected female calves., Procedure: Fresh and archival sera and necropsy tissue specimens were evaluated to determine the nature and extent of iron overload in captive and wild black rhinoceroses as well as other rhinoceros species., Results: Quantitative serum and tissue assays of iron and iron analytes, corroborated by histopathologic findings, indicated that these kindreds carried the greatest body burdens of iron yet found among captive black rhinoceroses. Fourteen of 18 rhinoceroses had the highest serum ferritin concentrations measured among 64 black rhinoceroses in captivity in the United States. Dams of affected calves had serum ferritin concentrations 2 orders of magnitude higher than clinically normal humans, equids, or free-ranging rhinoceroses. A neonatal serum sample from 1 affected female calf had a high ferritin concentration (approx 100-fold increase), but a male sibling of another affected female did not, suggesting a possible sex disparity in fetal response to maternal iron overload. Morphologic hallmarks of hemochromatosis were prominent in dams and grandams of affected calves., Conclusions and Clinical Relevance: Excessive maternal iron may affect female fetuses more than males, possibly inducing leukoencephalomalacia by catalyzing production of highly toxic hydroxyl free radicals during crucial periods of in utero development. Reduction of maternal iron overload may decrease the probability of developing leukoencephalomalacia and some other disorders commonly affecting rhinoceroses in captivity.

When rhinoceros species that are browsers in the wild are fed in captivity they become iron overloaded. Presumably, their iron-absorptive mechanisms have evolved to become highly efficient. In humans, mutations of the HFE gene cause increased iron absorption. To determine whether the HFE gene of rhinoceroses has undergone mutation as an adaptive mechanism to improve iron absorption from iron-poor diets, we have sequenced the entire coding region of the HFE genes of four species of rhinoceros. Two of these were browsing species and two were grazing species. Although the HFE gene has been well preserved across species, numerous nucleotide differences were found between rhinoceros and human or mouse, some of which changed deduced amino acids. Of these mutations, only one found in the black rhinoceros appears to be a viable candidate mutation that might adversely affect HFE function. This mutation, S88T, is in a highly conserved region that is involved in the interaction between transferrin receptor and HFE., (Copyright 2001 Academic Press.)