Article

Iron storage disease (haemosiderosis) in Blue-masked (Chloropsis venusta) and Lesser Green Leafbirds (Chloropsis cyanopogon)

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Abstract

Two Blue-masked Leafbirds (Chloropsis venusta) were presented in the Clinic for Exotic Pets, Reptiles and Birds Hanover with clinical signs of apathy, reduced food intake, weight loss, dyspnoea and abdominal swelling (visible hepatomegaly). One Blue-masked Leafbird and one Lesser Green Leafbird (Chloropsis cyanopogon) were presented for necropsy after being found dead without clinical signs. The pathological examination showed a discolored and enlarged liver in all four birds. The Lesser Green Leafbird had a poorly calcified broken egg in its shell gland (suspected of egg binding) and stones from the ground of the aviary in Its gizzard. The histopathologlcal examinations of the liver from all four birds revealed large amounts of granular pigment in the hepatocytes and mononuclear cells, which stained positive for haemosiderin with Berlin blue stain. The iron content of the livers from one of the Blue-masked Leafbirds and from the Lesser Green Leafbird was 6061 and 25266 mg/kg dry matter, respectively. Iron storage disease (hepatic hemosiderosis) was diagnosed based on the histopathological findings and the iron levels of the livers in all four leafbirds. An analysis of the main food components showed very high quantities of iron in the dried insects (2347 mg/kg dry matter), whereas the iron content of the commercial nectar preparation and the fruit fed to the birds was low (< 40 mg/kg dry matter). In the case of the Lesser Green Leafbird, the bird had used earth and stones from the ground of its aviary as a source of calcium. This behavior resulted in a very high iron intake and the bird developed hemosiderosis.

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