Resultado da pesquisa (3)
Termo utilizado na pesquisa steroidal saponins
#1 - Protodioscin levels in Brachiaria spp. in a sheep production system and a brief review of the literature of Brachiaria spp. poisoning in ruminants
Abstract in English:
Plants of the genus Brachiaria, used in several countries as forage, are poisonous to some livestock species. Their toxic principle is protodioscin, and the main form of clinical presentation of the toxicosis is hepatogenous photosensitization. Here we compare protodioscin levels in B. decumbens and B. brizantha and review the literature on the concentrations and methodologies of collection and analysis of the toxic principle in Brachiaria spp. and the risk of contamination of pastures by more toxic species that may facilitate poisoning by plants of this genus in sheep. The experiment was conducted in pastures originally formed by B. brizantha, with many B. decumbens invasion points. The occurrence of cases of poisoning by Brachiaria spp. was the criterion for confirming pasture toxicity. The forage samples were collected at ten random points every 28 days through manual grazing simulation. The samples were analyzed for protodioscin by high-performance liquid chromatography (HPLC) with light scattering by evaporation (ELSD) after being dried and crushed. In the flock of 69 sheep, five poisoning cases occurred, three sheep died, and two recovered. The protodioscin levels found in the evaluated pastures ranged from 0.70 to 0.45%; higher levels appeared in B. decumbens (7.09%) compared to 1.04% in B. brizantha. We suggest that Brachiaria spp. should be avoided in pastures where sheep are grazing.
Abstract in Portuguese:
Plantas do gênero Brachiaria, utilizadas em vários países como forragem, são tóxicas para várias espécies pecuárias. Seu princípio tóxico é a protodioscina, e a principal forma de apresentação clínica da toxicose é a fotossensibilização hepatógena. Este estudo teve como objetivo comparar os níveis de protodioscina em B. decumbens e B. brizantha e revisar a literatura sobre as concentrações e metodologias de coleta e análise do princípio tóxico em Brachiaria spp. e o risco de contaminação das pastagens por espécies mais tóxicas que podem facilitar a intoxicação por plantas desse gênero em ovinos. O experimento foi conduzido em pastagens originalmente formadas por B. brizantha, com diversos pontos de invasão por B. decumbens. Ocorrência de casos de intoxicação por Brachiaria spp. foi o critério para confirmação da toxicidade da pastagem. As amostras de forragem foram coletadas a cada 28 dias em dez pontos aleatórios por meio de simulação de pastejo manual. As amostras foram analisadas para protodioscina por cromatografia líquida de alta eficiência (HPLC) com dispersão de luz por evaporação (ELSD) após serem secadas e trituradas. No rebanho de 69 ovelhas, cinco desenvolveram a intoxicação, três morreram e duas se recuperaram. Os níveis de protodioscina encontrados nas pastagens avaliadas variaram de 0,70 a 0,45%; níveis mais elevados apareceram em B. decumbens (7,09%) em comparação com 1,04% em B. brizantha. Sugerimos que Brachiaria spp. deve ser evitada no pasto de ovelhas em pastejo.
#2 - Sheep poisoning by Panicum dichotomiflorum in northeastern Brazil, p.94-98
Abstract in English:
ABSTRACT. Riet-Correa F., Haraguchi M., Dantas A.F., Burakovas R.G., Yokosuka A., Mimaki Y., Medeiros R.M.T. & Matos P.F. 2009. Sheep poisoning by Panicum dichotomiflorum in northeastern Brazil. Pesquisa Veterinária Brasileira 29(1):94-98. Hospital Veterinário, Centro de Saúde e Tecnologia Rural, Universidades Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: franklin.riet@pq.cnpq.br
Different species of Panicum, including P. dichotomiflorum, have been reported as a cause of photosensitization in sheep, horses, cattle and goats. An outbreak of hepatogenous photosensitization occurred in 3 flocks of hair sheep in the Brazilian semiarid region. Eighty one out of 365 sheep were affected and 39 died. The main affected animals were nursing lambs and sheep younger than one year old. Donkeys, goats and cattle grazing in the same pasture were not affected. Clinical signs were edema of the head, followed by dermatitis, mainly in the face, ears, and croup, ocular discharge, corneal opacity with blindness, and redness of the coronary band and hoof. At necropsy of one affected lamb the liver was yellowish. Upon histologic examination scattered necrotic hepatocytes were observed in the liver and focal areas of necrosis of myocytes appeared in the heart. Samples of P. dicotomiflorum were analyzed by TLC and those containing saponins were isolated by HPLC using RP-C18 column and eluted with a mixture of MeOH and H2O. The isolated compounds were submitted to 1H and 13C NMR spectroscopy. Reactions were positive to furostanol saponins with the same Rf of the standard protodioscin (0.21) and methylprotodioscin (0.32). The spectroscopic results indicated a mixture of (25R)- and (25S)-protodioscin isomers in a proportion of 3:1, and methylprotodioscin.
Abstract in Portuguese:
ABSTRACT. Riet-Correa F., Haraguchi M., Dantas A.F., Burakovas R.G., Yokosuka A., Mimaki Y., Medeiros R.M.T. & Matos P.F. 2009. Sheep poisoning by Panicum dichotomiflorum in northeastern Brazil. Pesquisa Veterinária Brasileira 29(1):94-98. Hospital Veterinário, Centro de Saúde e Tecnologia Rural, Universidades Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: franklin.riet@pq.cnpq.br
Different species of Panicum, including P. dichotomiflorum, have been reported as a cause of photosensitization in sheep, horses, cattle and goats. An outbreak of hepatogenous photosensitization occurred in 3 flocks of hair sheep in the Brazilian semiarid region. Eighty one out of 365 sheep were affected and 39 died. The main affected animals were nursing lambs and sheep younger than one year old. Donkeys, goats and cattle grazing in the same pasture were not affected. Clinical signs were edema of the head, followed by dermatitis, mainly in the face, ears, and croup, ocular discharge, corneal opacity with blindness, and redness of the coronary band and hoof. At necropsy of one affected lamb the liver was yellowish. Upon histologic examination scattered necrotic hepatocytes were observed in the liver and focal areas of necrosis of myocytes appeared in the heart. Samples of P. dicotomiflorum were analyzed by TLC and those containing saponins were isolated by HPLC using RP-C18 column and eluted with a mixture of MeOH and H2O. The isolated compounds were submitted to 1H and 13C NMR spectroscopy. Reactions were positive to furostanol saponins with the same Rf of the standard protodioscin (0.21) and methylprotodioscin (0.32). The spectroscopic results indicated a mixture of (25R)- and (25S)-protodioscin isomers in a proportion of 3:1, and methylprotodioscin.
#3 - Patogênese, sinais clínicos e patologia das doenças causadas por plantas hepatotóxicas em ruminantes e eqüinos no Brasil, p.1-14
Abstract in English:
ABSTRACT.- Santos J.C.A., Riet-Correa F., Simões S.V.D. & Barros C.S.L. 2008. [Pathogenesis, clinical signs and pathology of diseases caused by hepatotoxic plants in ruminants and horses in Brazil.] Patogênese, sinais clínicos e patologia das doenças causadas por plantas hepatotóxicas em ruminantes e eqüinos no Brasil. Pesquisa Veterinária Brasileira 28(1):1-14. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: franklin.riet@pq.cnpq.br
Plants causing hepatic lesions in ruminants and horses constitute one important group of poisonous plants in Brazil. These plants can be placed in three major groups: plants causing acute liver necrosis; plants causing liver fibrosis; and plants causing hepatogenous photosensitization. For some of these plants the toxic principles are known. Cestrum parqui and Xanthium cavanillesi that cause acute liver necrosis contain carboxy-atractylosides. Senecio spp., Crotalaria spp., and Echium plantagineum that cause liver fibrosis contain pyrrolizidine alkaloids. As for the group of plants causing hepatogenous photosensibilization, Myoporum spp. contain furanosesquiterpenes, Lantana spp contain triterpenes, and Brachiaria spp. and Panicum spp. contain steroidal saponins. The clinical and pathologic features of the toxicosis caused by these phytotoxins, general mechanisms of production for the production of the clinical signs and the methods for diagnosis of hepatic failure in farm animals are reviewed.
Abstract in Portuguese:
ABSTRACT.- Santos J.C.A., Riet-Correa F., Simões S.V.D. & Barros C.S.L. 2008. [Pathogenesis, clinical signs and pathology of diseases caused by hepatotoxic plants in ruminants and horses in Brazil.] Patogênese, sinais clínicos e patologia das doenças causadas por plantas hepatotóxicas em ruminantes e eqüinos no Brasil. Pesquisa Veterinária Brasileira 28(1):1-14. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: franklin.riet@pq.cnpq.br
Plants causing hepatic lesions in ruminants and horses constitute one important group of poisonous plants in Brazil. These plants can be placed in three major groups: plants causing acute liver necrosis; plants causing liver fibrosis; and plants causing hepatogenous photosensitization. For some of these plants the toxic principles are known. Cestrum parqui and Xanthium cavanillesi that cause acute liver necrosis contain carboxy-atractylosides. Senecio spp., Crotalaria spp., and Echium plantagineum that cause liver fibrosis contain pyrrolizidine alkaloids. As for the group of plants causing hepatogenous photosensibilization, Myoporum spp. contain furanosesquiterpenes, Lantana spp contain triterpenes, and Brachiaria spp. and Panicum spp. contain steroidal saponins. The clinical and pathologic features of the toxicosis caused by these phytotoxins, general mechanisms of production for the production of the clinical signs and the methods for diagnosis of hepatic failure in farm animals are reviewed.
