PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

Amorim S.L., Medeiros R.M.T. & Riet-Correa F. 2005. [Experimental poisoning by Manihot glaziovii (Euphorbiaceae) in goats.] Intoxicação experimental por Manihot glaziovii (Euphorbiaceae) em caprinos. Pesquisa Veterinária Brasileira 25(3):179-187. Centro de Saúde e Tecnologia Rural, UFCG, Campus de Patos, 58700-000 Patos, PB, Brazil. E-mail: rmtmed@cstr.ufcg.edu.br Samples of fresh, dried and partially dried leaves of Manihot glaziovii Muell. Arg. were administered orally to Moxotó goats in single doses up to 12g/kg body weight (bw). The cyanide content of the plant samples was determined by the picrosodic paper test. The plant was collected from January to June 2004. When the goats with clinical signs were in lateral recumbency, they were treated intravenously with 50ml/100kg/bw of a 20% aqueous solution of sodium tiosulfate. Three experiments were performed. In Experiment 1, the plant was given immediately after collection to six goats; two ingested the plant after been ground and four ingested the plant without having been ground. In Experiment 2, the plant was maintained in the shade, in open air or inside plastic bags. The plastic bags were changed daily. The plant kept in plastic bags was given to 18 goats, 4, 8, 12, 16, 20, 24, 48, 72, 96 and 120 hours after collection. The plant kept in the open air was given to 13 goats, 4, 24, 48, 72 and 96 hours and 9, 10, 23 and 30 days after collection. In Experiment 3, the previously ground plant kept in the open air or inside plastic bags was administered 4, 8, 12, 16, 20, 24, 48, 72 and 96 hours after collection. Seventeen goats received the plant kept in plastic bags, and 16 goats the plant left in the open air. In Experiments 2 and 3, two or three goats were used for each period after collection, and the plant was given until the loss of its toxicity. Forty goats were used as controls for evaluation of the cardiac and respiratory frequencies. In Experiment 1, the ground and not ground plant had similar toxicity. In Experiment 2, the plant kept in the open air maintained its toxicity during the whole experiment (30 days), and the plant kept inside the plastic bags was toxic until 96 hours after collection. In Experiment 3, the ground plant, left in the open air or kept inside plastic bags, was toxic for 72 hours after collection. In all experiments clinical signs were characteristic of cyanide poisoning. All poisoned goats were treated successfully. In conclusion, Manihot glaziovii, which is used as forage in northeastern Brazil, should be ground and left for at least 96 hours in the open air before feeding to animals. The plant for preparing hay should be previously ground, and the hay should be given to animals also only 96 hours after its preparation.

• Poisonous plants plant poisoning Manihot glaziovii Euphorbiaceae cyanogenic plants hydrocyanic acid goats.

Abstract in Portuguese:

Amorim S.L., Medeiros R.M.T. & Riet-Correa F. 2005. [Experimental poisoning by Manihot glaziovii (Euphorbiaceae) in goats.] Intoxicação experimental por Manihot glaziovii (Euphorbiaceae) em caprinos. Pesquisa Veterinária Brasileira 25(3):179-187. Centro de Saúde e Tecnologia Rural, UFCG, Campus de Patos, 58700-000 Patos, PB, Brazil. E-mail: rmtmed@cstr.ufcg.edu.br Samples of fresh, dried and partially dried leaves of Manihot glaziovii Muell. Arg. were administered orally to Moxotó goats in single doses up to 12g/kg body weight (bw). The cyanide content of the plant samples was determined by the picrosodic paper test. The plant was collected from January to June 2004. When the goats with clinical signs were in lateral recumbency, they were treated intravenously with 50ml/100kg/bw of a 20% aqueous solution of sodium tiosulfate. Three experiments were performed. In Experiment 1, the plant was given immediately after collection to six goats; two ingested the plant after been ground and four ingested the plant without having been ground. In Experiment 2, the plant was maintained in the shade, in open air or inside plastic bags. The plastic bags were changed daily. The plant kept in plastic bags was given to 18 goats, 4, 8, 12, 16, 20, 24, 48, 72, 96 and 120 hours after collection. The plant kept in the open air was given to 13 goats, 4, 24, 48, 72 and 96 hours and 9, 10, 23 and 30 days after collection. In Experiment 3, the previously ground plant kept in the open air or inside plastic bags was administered 4, 8, 12, 16, 20, 24, 48, 72 and 96 hours after collection. Seventeen goats received the plant kept in plastic bags, and 16 goats the plant left in the open air. In Experiments 2 and 3, two or three goats were used for each period after collection, and the plant was given until the loss of its toxicity. Forty goats were used as controls for evaluation of the cardiac and respiratory frequencies. In Experiment 1, the ground and not ground plant had similar toxicity. In Experiment 2, the plant kept in the open air maintained its toxicity during the whole experiment (30 days), and the plant kept inside the plastic bags was toxic until 96 hours after collection. In Experiment 3, the ground plant, left in the open air or kept inside plastic bags, was toxic for 72 hours after collection. In all experiments clinical signs were characteristic of cyanide poisoning. All poisoned goats were treated successfully. In conclusion, Manihot glaziovii, which is used as forage in northeastern Brazil, should be ground and left for at least 96 hours in the open air before feeding to animals. The plant for preparing hay should be previously ground, and the hay should be given to animals also only 96 hours after its preparation.

Abstract in English:

ABSTRACT.- Tokarnia C.H., Peixoto P.V, Brito M.F., Duarte M.D. & Brust L.A.C. 1999. [Experimental studies in cattle with cyanogenic plants.] Estudos experimentais em bovinos com plantas cianogênicas. Pesquisa Veterinária Brasileira 19(2):84-90. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23851-970, Brazil. These studies were performed in arder to obtain additional data on Brazilian cyanogenic plants. Three animals, severely poisoned by Piptadenia macrocarpa ( =Anadenanthera macrocarpa), recovered readilywhen treated intravenously with 660 mg/kg of sodium hyposulphite (sodium thiosulphate) plus 30 g dissolved in water given by stomach tube. Fresh leaves (in the sprouting phase), fed in October, were more poisonous than mature leaves fed in March. Dried leaves slowly lost their toxicity within a few months. Both the fresh and dried leaves of Piptadenia viridiflora showed similar toxic effects to P. macrocarpa. As this was also readily reversed by the administration of sodium hyposulphite in two animals, P. viridiflora can be included in the group of toxic cyanogenic plants. Four animals severely poisoned by the leaves of Holocalyx glaziovii ( =Holocalyx balansae) also recovered readily after receiving sodium hyposulphite. The dried leaves of H. glaziovii also slowly lost their toxicity within a few months. Two animals severely poisoned by the leaves of Manihot glaziovii also recovered readily with sodium hyposulphite. However, dried leaves were no longer poisonous. The leaves of H. glaziovii and of M. glaziovii always gave a quick (in less than 5 minutes) positive reaction to the picrate test for cyanide. Those of P. macrocarpa and P. viridiflora reacted more slowly (after 15 and 10 to 30 minutes respectively) when in the sprouting stage, and even slower when the leaves were mature. The slower reactions seen with Piptadenia spp indicate a slower breakdown of the hidrocyanic glycosides and this also explains the longer course of poisoning seen in cattle fed these species. The dried leaves of Piptadenia spp and also of H. glaziovii gave slower reactions than the fresh leaves. These data permit the conclusion that the picrate test for cyanide is of relative value when evaluating the amount of cyanogenic glycosides in plants.

• Poisonous plants hydrocyanic poisoning Piptadenia macrocarpa Anadenanthera macrocarpa Piptadenia viridiflora Holocalyx glaziovii Manihot glaziovii cattle Plantas tóxicas intoxicação cianídrica bovinos.

Abstract in Portuguese:

RESUMO.- Tokarnia C.H., Peixoto P.V, Brito M.F., Duarte M.D. & Brust L.A.C. 1999. [Experimental studies in cattle with cyanogenic plants.] Estudos experimentais em bovinos com plantas cianogênicas. Pesquisa Veterinária Brasileira 19(2):84-90. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23851-970, Brazil. O presente estudo experimental foi realizado com a finalidade de preencher lacunas no conhecimento sobre algumas plantas cianogênicas no Brasil. Observou-se que três bovinos gravemente intoxicados por Piptadenia macrocarpa (=Anadenanthera macrocarpa), desenvolveram o clássico quadro de intoxicação cianídrica, mas se recuperaram de imediato quando tratados pela aplicação endovenosa de 660 mg/kg de hipossulfito (tiossulfato) de sódio, associada à administração de 30 g da mesma substância, dissolvidos na água, por sonda esofagiana. Verificou-se ainda que as folhas dessa planta são mais tóxicas em outubro (fase de brotação) do que em março (folhas maduras) e que as folhas dessecadas perdem lentamente em toxidez, no decorrer de meses. As folhas frescas, e também a dessecadas, de Piptadenia viridiflora produziram quadro clínico-patológico muito semelhante ao observado na intoxicação por P. macrocarpa, também rapidamente reversível, em dois bovinos, pela administração de hipossulfito de sódio, o que permite inseri-la entre as plantas cianogênicas. Quatro bovinos gravemente intoxicados pelas folhas de Holocalyx glaziovii se recuperaram prontamente após a administração de hipossulfito de sódio; verificou-se que as folhas dessecadas dessa planta perdem lentamente em toxidez, no decorrer de meses. Dois bovinos gravemente intoxicados pelas folhas de Manihot glaziovii se recuperaram de imediato pelo tratamento com hiposulfito de sódio. As folhas dessecadas desta planta perderam a sua toxidez. Com Holocalyx glaziovii e Manihot glaziovii, as reações positivas pelo teste do papel picro-sódico foram sempre muito rápidas (dentro de 5 minutos), enquanto que com Piptadenia macrocarpa e Piptadenia viridiflora as reações foram mais lentas (dentro de 15 minutos e de 10 a 30 minutos respectivamente) para a brotação, e ainda mais retardàdas para as folhas maduras. A·reação mais lenta, observada no teste do papel picro-sódico com as folhas de Piptadenia spp., indica·um desdobramento mais vagaroso do glicosídeo cianogênico e está de acordo com a evolução mais longa observada na intoxicação por essas plantas. As folhas dessecadas de Piptadenia spp e também de H. glaziovii forneceram reações mais lentas que as folhas frescas. Esses dados permitem concluir que o teste do papel picro-sódico tem valor apenas relativo na avaliação das concentrações de glicosídeos cianogênicos em material vegetal.