RESUMO.-Este trabalho teve por objetivo realizar um levantamento sobre as plantas tóxicas para ruminantes e equídeos na Mesorregião Norte do Piauí. Foram feitas 71 entrevistas a médicos veterinários, engenheiros agrôno-mos, técnicos agrícolas e produtores de 16 municípios, entrevistando pelo menos quatro pessoas por município. As plantas comprovadamente tóxicas que foram apontadas com maior frequência na região estudada foram Ipomoea asarifolia, que causa intoxicações em pequenos ruminantes em todas as áreas visitadas. Stryphnodendron coriaceum pelas mortes que ocasiona é, aparentemente, a planta que causa maiores perdas econômicas na me- The objective of this study was to survey toxic plants for ruminants and equidae in northern Piauí. Seventy one persons were interviewed, including farmers, veterinary practitioners, agronomists, and agrarian technicians from 16 municipalities, performing at least four interviews in each municipality. The most common plant mentioned as a cause of poisoning was Ipomoea asarifolia, which is a well known cause of tremogenic disease in ruminants. Stryphnodendron coriaceum which causes digestive signs was referred as a common cause of death, and is probably the plant that causes most cattle deaths in the region. Enterolobium contortisiliquum was also mentioned as a frequent cause of digestive signs, abortion and photosensitization in cattle. Outbreaks of nephrosis caused by Thiloa glaucocarpa are frequent at the beginning of the raining season. Poisoning by the cyanogenic plants Manihot spp. e Piptadenia macrocarpa are a cause of peracute deaths. Other plants mentioned as toxic were Buchenavia tomentosa, Caesalpinia sp., Brunfelsia sp., Luetzelburgia sp., Hybantus ipecaconha, Phisalys angulata, and Spondias luta. Farmers report that goats are poisoned by the ingestion of the pods of Luetzelburgia sp., which causes digestive signs and death. The ingestion of the fruits of Buchenavia tomentosa is associated with digestive signs and and abortion in ruminants. Brunfelsia sp. is mentioned as a cause of nervous signs at the start of the raining season and donkeys are apparently more affected. The consumption of the fruits of Spondias luta are associated with diarrhea in goats. Recent unpublished experiments demonstrated the toxicity of Brunfelsia sp. as a cause of nervous signs and of Luetzelburgia sp. as a cause of digestive signs in goats. Experiments with other plants are necessary to confirm their toxicity.

"Quantitative Buffy Coat" (QBC) is a direct and fast fluorescent method used for the identification of blood parasites. Since Leishmania chagasi circulates in blood, we decided to test it in American visceral leishmaniasis (AVL). Bone marrow (BM) and peripheral blood (PB) of 49 persons and PB of 31 dogs were analyzed. QBC was positive in BM of 11/11 patients with AVL and in 1/6 patients with other diseases. Amastigotes were identified in PB of 18/22 patients with AVL and in none without AVL. The test was positive in 30 out of the 31 seropositive dogs and in 28/28 dogs with Leishmania identified in other tissues. QBC is a promising method for diagnosis of human AVL, and possibly for the exam of PB of patients with AVL/AIDS, for the control of the cure and for the identification of asymptomatic carriers. Because it is fast and easy to collect and execute, QBC should be evaluated for programs of reservoir control.

Farmers report that the pods of Luetzelburgia auriculata cause digestive signs and death when ingested by goats. To demonstrate the toxicity of the pods of this plant 12 goats were divided into 4 groups of 3 goats each. Groups 1, 2, 3 and 4 were administered 2.5, 1, 0.5 and nil g of pods per kg body weight, respectively. Goats in Groups 1 and 2 developed decreased ruminal movements followed by anorexia, depression and soft feces or diarrhea. Goats in Group 1 died 59-106 h after first showing clinical signs. Goats in Group 2 also regurgitated rumen content, but all recovered 65-90 h after first showing clinical signs. The only clinical sign shown by goats in Group 3 was regurgitation of rumen content, and all goats recovered 5.5-24 h after first regurgitating. All goats in Group 4 remained normal. The goats that died were necropsied and found to have a reddish mucosa of the forestomachs that detached easily from the underlying tissues. Other lesions included diffuse reddening of the mucosa of the abomasum and intestine. Histological examination of the mucosa of the forestomachs showed diffuse ballooning degeneration of keratinocytes, with necrosis and vesicle and pustule formation in the epithelium. In some areas there was sloughing of the ruminal epithelium. These results demonstrate that the pods of L. auriculata are toxic and responsible for field outbreaks of poisoning in goats in the state of Piaui.

Farmers in the State of Piauí in northeastern Brazil reported nervous signs in ruminants and donkeys after ingestion of Brunfelsia uniflora at the start of the rainy season when the plant is flowering. Leaves of the plant, collected at the start or at the end of the rainy season, were administered in single doses of 5-20 g/kg body weight to 8 sheep and 3 donkeys. Two sheep and 1 donkey that ingested 10 g/kg of the plant in November at the start of the rainy season, when the plant was flowering, developed severe convulsions and diarrhea. One sheep was euthanized and autopsied, and no significant lesions were found. The other sheep and the donkey recovered. Four sheep and one donkey that ingested 10 or 20 g/kg of leaves collected in April, at the end of the rainy season, did not show clinical signs. One donkey that ingested 5 g/kg of leaves collected in November developed diarrhea and recovered. These results demonstrate the toxicity of B. uniflora for livestock and suggest that the plant is toxic at these doses only during the start of the rainy season.