Acute aflatoxicosis outbreak in rheas (Rhea americana) in Brazil: Case report.

Aflatoxins are mycotoxins capable of contaminating food, and can cause toxic effects, teratogenicity, mutagenicity, carcinogenicity, and immune system depression. The presence of fungi which produce this metabolite in ingredients that compose the animal feed increased the risk of the emergence of aflatoxicosis. The objective of this study was to report an aflatoxicosis outbreak in rheas (Rhea americana) from a farm in Teresina, PI, Brazil, fed with commercial feed. After the deaths of four animals, epidemiological data were collected and complementary examinations were performed, including necropsy, histopathology, parasitology, blood culture, in addition to the analysis of the presence of toxins in the birds' feed. The diagnosis was based on the acute clinical signs, necropsy findings, which included carcass jaundice, an oedematous, yellowish, friable liver of increased size, and histopathological findings of moderate to severe congestion in all organs. The parasitological and microbiological tests performed were negative, not indicating systemic infectious causes. The analysis of the presence of mycotoxins revealed the existence of Aflatoxins B1, B2 and G1 in the commercial feed supplied, constituting a total of 66.89 μg/kg. This amount of aflatoxin exceeds the maximum level allowed by the Brazilian legislation. To our knowledge this is the first report of aflatoxicosis in rheas, and emphasizes the importance of the diagnosis, control, and prevention of mycotoxins in the quality of food provided to animals kept ex situ.