Spontaneous poisoning of cattle by onion (Allium cepa) in Brazil

The state of Santa Catarina is the largest national producer of onions. The consumption of onion (Allium cepa) by domestic animals can cause hemolytic anemia and hyperhemoglobinemia of Heinz bodies in erythrocytes. The epidemiological data and the pathological clinical picture were obtained during a visit to the property where the disease occurred. A herd of 54 beef cattle from a property in the municipality of Bom Retiro/SC, was placed in an onion crop, which had not been completely harvested because it was outside the desired standard for trade. The animals remained in this field for eight days. At the end of this period, all of them presented apathy, anorexia, brown urine and mucous membranes and an onion odor on expiration. The macroscopic changes observed were pale mucous membranes, blood with decreased viscosity and increased clotting time, liver with an evident lobular pattern and remains of onion in the rumen. The carcass gave off a strong onion odor. By histological analysis, there was central lobular coagulation necrosis in bridging in the liver. In the kidneys, there were intracytoplasmic hyaline droplets in tubular epithelial cells and a deposit of eosinophilic material in the lumen of the tubules. For the diagnosis of onion poisoning, epidemiological data associated with clinical signs, such as pale mucous membranes with evidence of hemoglobin pigmentation (brown mucosa) and hemoglobinuria, should be taken into account. This article seems to be the first report of onion poisoning in cattle in Brazil. RESUMO: O estado de Santa Catarina é o maior produtor nacional de cebola. O consumo de cebola (Allium cepa) por animais domésticos pode causar anemia hemolítica, hiper-hemoglobinemia de corpúsculos de Heinz nos eritrócitos. Os dados epidemiológicos e o quadro clínico-patológico foram obtidos em visita à propriedade onde a enfermidade ocorreu. Um rebanho de 54 bovinos de corte de uma propriedade localizada no município de Bom Retiro/SC, foi colocado em uma lavoura de cebola, a qual não havia sido completamente colhida por estar fora do padrão desejado para o comércio. Os animais permaneceram por um período de oito dias nesta lavoura e, ao final deste período, todos apresentaram apatia, anorexia, urina e mucosas de coloração marrom e odor de cebola na expiração. As alterações macroscópicas observadas foram mucosas pálidas, sangue com viscosidade diminuída e aumento do tempo de coagulação, fígado com padrão lobular evidente e restos de cebola no rúme