RESUMO
A disease of the nervous system was observed in goats from two farms of the semiarid of the state of Paraíba, northeastern Brazil. Ipomoea sericophylla was found in one farm and I. riedelii in the other. Both plants were administered experimentally to five goats each. Both plants induced clinical signs similar to those observed in spontaneous cases. Two goats died spontaneously and five were euthanatized. Three goats recovered after the withdrawal of the plants. Histological examination showed that all goats that died spontaneously or were euthanized had diffuse vacuolation of neurons, macrophages of lymphatic tissues, and epithelial cells of pancreas, thyroid, renal tubules and liver. On electron microscopy of Purkinje cells, numerous dilated membrane bordered vacuoles were identified as lysosomes. On lectin-histochemical analysis, cerebellar cells gave positive reactions to Concanavalia ensiformis, Triticum vulgaris, and succinylated-T. vulgaris, which indicate the storage of alpha-D-mannose, alpha-D-glucose, beta-D-N-acetyl-glucosamine, and acetyl-neuraminic acid. The chemical analysis of I. sericophylla and I. riedelii showed 0.11 and 0.14% of swainsonine, respectively. The latter also contained calystegines B1, B2 and C1. It is concluded that I. sericophylla and I. riedelli cause a lysosomal storage disease.
Assuntos
Ipomoea/toxicidade , Doenças do Sistema Nervoso/etiologia , Intoxicação por Plantas/fisiopatologia , Alcaloides/análise , Animais , Brasil , Cabras , Doenças do Sistema Nervoso/patologia , Doenças do Sistema Nervoso/fisiopatologia , Extratos Vegetais/análise , Intoxicação por Plantas/patologia , Swainsonina/análise , TropanosRESUMO
Green leaves of Ipomoea asarifolia were dosed to 10 goats. Nine goats ingesting 5-37 g/kg bw daily had clinical signs in 4-38 days. One goat ingesting 2.5 g/kg bw daily during 125 days and two control goats had no clinical signs. Clinical signs were characteristic for a tremorgenic syndrome. Five goats recovered in 4-9 days after the withdrawal of the plant. Two goats died spontaneously and three were euthanased for histologic and ultrastructural studies. No significant lesions were observed at necropsies or on the histologic and ultrastructural studies. Samples of the plant analyzed for enzymatic inhibitors were negative for calystegines and contained an almost undetectable amount of swainsonine (less than 0.001%). It is concluded that I. asarifolia causes a tremorgenic syndrome due to an unknown tremorgenic phytotoxins or mycotoxins.