ABSTRACT
Com o objetivo de avaliar a toxicidade de diferentes concentrações das favas de Stryphnodendron fissuratum em vacas prenhes, as favas desta árvore foram moídas, misturadas à ração comercial e fornecidas a oito vacas nas doses totais de 6,5g/kg, 7,5g/kg, 9g/kg e 10g/kg. Os animais que receberam doses de 6,5g/kg pariram bezerros normais e aqueles que receberam 7,5g/kg pariram bezerros fracos que não sobreviveram. Doses de 9g/kg resultaram no nascimento de um bezerro imaturo e de outro bezerro com distiquíase, opacidade congênita das córneas e microftalmia. Ambas as vacas que ingeriram 10g/kg morreram, porém uma vaca abortou antes de morrer. Nas vacas que morreram, as lesões macroscópicas e histológicas do sistema digestivo e fígado foram semelhantes às descritas anteriormente na intoxicação por S. fissuratum. Nos bezerros e no feto abortado não foram observadas lesões macroscópicas ou histológicas significantes. A análise fitoquímica dos extratos metanólicos das favas de S. fissuratum revelou a presença de taninos hidrossolúveis, proantocianidinas, leucoantocianidinas e da saponina triterpénica β-amirina. Saponinas triterpénicas têm sido associadas com a toxicidade das favas de Stryphnodendron spp. e Enterolobium spp., que causam sinais clínicos semelhantes aos observados na intoxicação por S. fissuratum. Esta pesquisa confirmou a toxicidade das favas de S. fissuratum para bovinos, no entanto não foram confirmados os efeitos abortivos das mesmas, pois o aborto e as mortes neonatais observadas podem ser decorrentes dos efeitos tóxicos da planta nas mães. Novas pesquisas são necessárias para pesquisar se as favas da planta causam malformações semelhantes às observas em um dos bezerros nascidos vivos.
To evaluate the toxicity of different concentrations of pods of Stryphnodendron fissuratum to pregnant cows, the pods of this tree were grounded, mixed in a commercial food and given to eight pregnant cows in total doses of 6.5g/kg, 7.5g/kg, 9g/kg and 10g/kg. The animals that received doses of 6.5g/kg delivered normal calves and those that received 7.5g/kg delivered weak calves that did not survive. Doses of 9g/kg resulted in the birth of an immature calf and another with congenital bilateral distichiasis, corneal opacity, and microphthalmia. Both cows that ingested 10g/kg died, and one of these aborted before death. In the dead cows, the gross and histological lesions of the digestive system and liver were similar to those previously described in S. fissuratum poisoning. No significant lesions were observed in the calves and in the aborted fetus. The phytochemical analysis of methanol extracts from pods of S. fissuratum revealed the presence of soluble tannins, proanthocyanidins, leucoanthocyanidins and the triterpenoid saponin β-amyrin. Triterpenoid saponins had been associated with the toxicity of Stryphnodendron spp. and Enterolobium spp., which cause clinical signs similar to those observed in the poisoning by S. fissuratum. The results presented herein confirmed the toxicity of S. fissuratum to bovines. However, the abortive effects of this plant was not confirmed; thus because the abortion and neonatal deaths could be due to the toxicity of the pods to the cows. New research should be done to demonstrate if S. fissuratum is a cause of malformations similar to those observed in one of the calves born from the treated cows.
Subject(s)
Animals , Female , Pregnancy , Cattle/metabolism , Fabaceae/toxicity , Pregnancy, Animal , Plants, Toxic/toxicity , Digestive System , LiverABSTRACT
Three outbreaks of primary photosensitization caused by Froelichia humboldtiana are reported in the semiarid region of the states of Pernambuco and Paraíba, in northeastern Brazil. The disease occurred from March to June 2011, affecting 27 bovines out of a total of 70. The main lesions consisted of dermatitis of the white skin, with edema and necrosis. All the bovines recovered after removal from the areas invaded by F. humboldtiana. To produce the disease experimentally, one bovine with white skin was placed for 14 days into an area with F. humboldtiana as the sole forage. This bovine presented photodermatitis on the third day of consumption. The serum concentrations of total, indirect, and conjugated bilirubin and the serum activities of gamma-glutamyl transferase (GGT) and aspartate-aminotransferase (AST) in the spontaneously affected cattle and in the experimental cattle remained within normal ranges. It is concluded that F. humboldtiana causes primary photosensitization in cattle in northeastern Brazil.
