First report of Trypanosoma vivax outbreak in dairy cattle in São Paulo state, Brazil

Esta é a primeira descrição de um surto de Trypanosomavivax ocorrido no Estado de São Paulo, no município de Lins. Animais acometidos apresentaram febre, icterícia, diminuição da produção de leite, perda de peso, diarreia profusa, abortos, anemia, leucocitose e hiperfibrigenemia. Foram registrados 31 óbitos de vacas e bezerros em 1.080 bovinos no total. Três vacas apresentaram sintomatologia nervosa, como dismetria, ataxia e fraqueza muscular, além de ptialismo, aumento de linfonodos e edema submandibular. Hemoparasitas flagelados foram observados em esfregaços sanguíneos, e a espécie de tripanossomo foi diagnosticada como T.vivax por PCR. A cepa de T. vivax mostrou ser resistente ao tratamento com aceturato de diaminozeno e a infecção disseminou rapidamente no rebanho. Pelo ELISA, observou-se que 98,36% (599) das amostras de soro colhidas apresentaram títulos positivos para IgG anti-T.vivax. O surto ocorreu em condições de baixa precipitação pluviométrica, fato que indica que outros fatores estavam envolvidos na ocorrência desse surto, como a ausência de tabanídeos e a grande presença de Haematobia irritans e Stomoxys calcitrans, cujo aumento populacional pode ser devido ao uso de resíduos de usinas de açúcar e álcool nos canaviais que circundavam a granja leiteira.

Spontaneous poisoning by Hovenia dulcis in dairy cattle in Southwest Parana, Brazil

Livestock poisoning by plants is a frequent occurrence which determines severe losses, such as the fall in the milk and meat production, the cost of expensive treatments, the state of immunosuppression, or even the animal's death. Cattle ingest toxic plants only when there is food shortage, when they cannot select what they eat, or when they ingest food for preference, which is the case of Hovenia dulcis fruits, very rich in sucrose. This plant is widely distributed in the southern and southeastern Brazilian regions. In literature, there are some cases of severe human liver injury associated with a long-term of H. dulcis leaf and fruit tea intake, and only one report regarding spontaneous poisoning of goats caused by this plant ingestion. However, its toxic effects associated with spontaneous ingestion by cattle have never been reported. This paper reports the first case of spontaneous poisoning in cattle by H. dulcis, which occurred in a dairy farm in southwest Paraná, Brazil. Three cattle individuals showed anorexia, ruminal atony, severe diarrhea and neurological tournament, head pressing, blindness, ataxia, and circling. The necropsy of the animals was done, and the remaining alterations were restricted to the digestive system and brain. The clinical signs presented by the animals are characteristic of polioencephalomalacia (PEM), caused by changes in the thiamine metabolism. Furthermore, clinical signs, gross, and microscopic lesions as well as the large amount of the plant throughout the digestive segment led to a diagnosis.