Resultado da pesquisa (9)
Termo utilizado na pesquisa toxidez
#1 - Study about the sensitivity of goats to the toxicity of crotalarias poisonous for cattle aiming their use for prophylactic measures, 35(6):501-512
Abstract in English:
ABSTRACT.- Pires A.P.C., Oliveira M.C., Braga K.M., Malafaia P., Barros J.P.N., Tokarnia C.H. & Brito M.F. 2015. [Study about the sensitivity of goats to the toxicity of crotalarias poisonous for cattle aiming their use for prophylactic measures.] Estudo sobre a sensibilidade dos caprinos à toxidez de crotalárias tóxicas para bovinos visando a sua utilização na profilaxia. Pesquisa Veterinária Brasileira 35(6):501-512. Curso de Pós-Graduação em Medicina Veterinária, Universidade Federal Rural do Rio de Janeiro, BR-465 Km 7, Seropédica, RJ 23890-000, Brazil. E-mail: anap.castropires@gmail.com
Plant poisoning is known to be one of the most important causes of death of adult cattle in Brazil. As there are not many possibilities for treatment, all efforts must focus on application of alternative prophylactic measures, among them the use of a less sensitive animal species in areas of the occurrence of certain plants. This study aimed to ascertain the sensibility of goats to crotalarias (Crotalaria spectabilis and Crotalaria juncea), so that this animal species could be used as a prophylactic measure against those plants poisonous for cattle. Single or daily doses of seeds of Crotalaria spectabilis and Crotalaria juncea were given to eight young adult goats of both sexes divided randomly in two groups of four goats, e.g. one group for each plant. None of the four goats that received seeds of Crotalaria juncea developed clinical sings of poisoning or showed changes in the biochemistry examination. Out of the four goats that received seeds of Crotalaria spectabilis, three died. One goat received a 20g/kg single dose of seeds and developed signs of acute poisoning. Postmortem and histopathological examination revealed marked centrilobular hemorrhagic necrosis. The other two goats developed chronic poisoning by the administration of 2g/kg daily doses of seeds for 35 and 150 days respectively. One goat showed severe interstitial pneumonia and mild hepatic lesions, while the other goat presented only chronic hepatic lesions. Both goats showed transient changes in the biochemistry examination. The fourth goat received a 10g/kg single dose of seeds and did not develop significant clinical or biochemical changes. The results of the present study showed that goats are not indicated to be used as a prophylactic measure against poisoning by Crotalaria spectabilis, but can be recommended as a prophylactic measure against poisoning by Crotalaria juncea.
Abstract in Portuguese:
RESUMO.- Pires A.P.C., Oliveira M.C., Braga K.M., Malafaia P., Barros J.P.N., Tokarnia C.H. & Brito M.F. 2015. [Study about the sensitivity of goats to the toxicity of crotalarias poisonous for cattle aiming their use for prophylactic measures.] Estudo sobre a sensibilidade dos caprinos à toxidez de crotalárias tóxicas para bovinos visando a sua utilização na profilaxia. Pesquisa Veterinária Brasileira 35(6):501-512. Curso de Pós-Graduação em Medicina Veterinária, Universidade Federal Rural do Rio de Janeiro, BR-465 Km 7, Seropédica, RJ 23890-000, Brazil. E-mail: anap.castropires@gmail.com
A intoxicação por plantas é sabidamente uma das principais causas de morte de bovinos adultos no Brasil. Uma vez que pouco pode ser feito no que diz respeito ao tratamento destas intoxicações, os esforços devem se concentrar na adoção de medidas profiláticas alternativas, como a utilização de uma espécie menos sensível no local de ocorrência de determinadas plantas. Objetivou-se com esse trabalho verificar a sensibilidade de caprinos às crotalárias (Crotalaria spectabilis e Crotalaria juncea) para que estes possam ser utilizados na profilaxia da intoxicação por essas plantas em bovinos. Sementes de C. spectabilis e C. juncea foram fornecidas em doses únicas ou diárias a oito caprinos adultos jovens, de ambos os sexos, divididos aleatoriamente em dois grupos de quatro animais (um grupo para cada planta). Dos quatro caprinos que receberam as sementes de C. juncea, nenhum desenvolveu sinais clínicos de intoxicação ou apresentou alterações significativas no exame bioquímico. Entre os quatro caprinos que receberam sementes de C. spectabilis três morreram. Um animal recebeu uma dose única de 20g/kg de sementes da planta e desenvolveu sinais de intoxicação aguda, caracterizadas macro e microscopicamente por necrose hemorrágica centrolobular. Os outros dois caprinos desenvolveram um quadro de intoxicação crônica pela administração de doses diárias de 2g/kg de sementes da planta por 35 e 150 dias respectivamente. Um animal apresentou uma marcada pneumonia intersticial e lesões hepáticas leves, enquanto no outro caprino observaram-se apenas lesões hepáticas crônicas. Ambos os animais apresentaram alterações transitórias ao exame bioquímico. O quarto caprino recebeu a dose única de 10g/kg, sobreviveu e não apresentou alterações clínicas ou da bioquímica sanguínea significativas. Os resultados do trabalho mostraram que não se deve usar caprinos como medida profilática na intoxicação por C. spectabilis, mas que pode se recomendar esta espécie na profilaxia da intoxicação por C. juncea.
#2 - Variação da toxidez de Arrabidaea bilabiata (Bignoniaceae) em coelhos
Abstract in English:
ABSTRACT.- Jabour F.F., Seixas J.N., Tokarnia C.H. & Brito M.F. 2006. [Variation of the toxicity of Arrabidaea bilabiata (Bignoniaceae) in rabbits.] Variação da toxidez de Arrabidaea bilabiata (Bignoniaceae) em coelhos. Pesquisa Veterinária Brasileira 26(3):171-176. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23.890-000, Brazil. E-mail: flaviajabour@bol.com.br
The dried and powdered mature leaves and sprouts of Arrabidaea bilabiata (fam. Bignoniaceae), a liana or scandent shrub, were administered by stomach tube to 15 rabbits at doses of 0.25-6.0g/kg. The lowest dose of the sprouts collected in October (End of the dry season) causing death was 0.5g/kg, whilst the lowest lethal dose of sprouts collected in May (End of the rainy season) was 1.0g/kg. With the mature leaves collected in October the lowest lethal dose was of 4.0g/kg, and the lowest lethal dose of the mature leaves collected in May was 6.0g/kg. The clinical course of the poisoning was peracute. The rabbits all of a sudden fell down with struggling movements, difficult and spaced breathing, and died. At necropsy, significant alterations were not observed and histopatological examination showed, as the more important changes, vacuolar hydropic degeneration of epithelial cells of the distal convoluted renal tubules, diffuse vacuolation of the cytoplasm and necrosis of hepatocytes, presence of eosinophilic sphaerules in the sinusoids, groups of heart muscle fibers with increased eosinophilia, besides congestion in the kidneys, liver, heart and lungs. It was concluded that the toxicity of A. bilabiata varies according to the season of the year and the growth stage of the plant. The plant was most toxic in October and the sprouts were more toxic than the mature leaves, confirming the data previously obtained in experiments with cattle and buffalos.
Abstract in Portuguese:
ABSTRACT.- Jabour F.F., Seixas J.N., Tokarnia C.H. & Brito M.F. 2006. [Variation of the toxicity of Arrabidaea bilabiata (Bignoniaceae) in rabbits.] Variação da toxidez de Arrabidaea bilabiata (Bignoniaceae) em coelhos. Pesquisa Veterinária Brasileira 26(3):171-176. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23.890-000, Brazil. E-mail: flaviajabour@bol.com.br
The dried and powdered mature leaves and sprouts of Arrabidaea bilabiata (fam. Bignoniaceae), a liana or scandent shrub, were administered by stomach tube to 15 rabbits at doses of 0.25-6.0g/kg. The lowest dose of the sprouts collected in October (End of the dry season) causing death was 0.5g/kg, whilst the lowest lethal dose of sprouts collected in May (End of the rainy season) was 1.0g/kg. With the mature leaves collected in October the lowest lethal dose was of 4.0g/kg, and the lowest lethal dose of the mature leaves collected in May was 6.0g/kg. The clinical course of the poisoning was peracute. The rabbits all of a sudden fell down with struggling movements, difficult and spaced breathing, and died. At necropsy, significant alterations were not observed and histopatological examination showed, as the more important changes, vacuolar hydropic degeneration of epithelial cells of the distal convoluted renal tubules, diffuse vacuolation of the cytoplasm and necrosis of hepatocytes, presence of eosinophilic sphaerules in the sinusoids, groups of heart muscle fibers with increased eosinophilia, besides congestion in the kidneys, liver, heart and lungs. It was concluded that the toxicity of A. bilabiata varies according to the season of the year and the growth stage of the plant. The plant was most toxic in October and the sprouts were more toxic than the mature leaves, confirming the data previously obtained in experiments with cattle and buffalos.
#3 - Estudo comparativo da toxidez de Palicourea juruana (Rubiaceae) para búfalos e bovinos
Abstract in English:
Oliveira C.M.C., Barbosa J.D., Macedo R.S.C., Brito M.F., Peixoto P.V. & Tokarnia C.H. 2004. [A comparative study of the toxicity of Palicourea juruana (Rubiaceae) to buffalo and cattle.] Estudo comparativo da toxidez de Palicourea juruana (Rubiaceae) para búfalos e bovinos. Pesquisa Veterinária Brasileira 24(1):27-30. Escola de Medicina Veterinária, Campus Castanhal, Universidade Federal do Pará, Rua Maximino Porpino 1000, Castanhal, PA 68743-080, Brazil. E-mail: tokarnia@ufrrj.br
An experimental study was performed to establish the toxicity of Palicourea juruana for buffaloes and to add new data on the toxicity of this plant for cattle. The clinical and pathological pictures were similar, but a comparison of the lethal doses for buffaloes (1-2g/kg) and cattle (0.25g/kg) shows that the buffalo is at least 4 times more resistant. In experiments performed 10 years earlier with the fresh leaves - collected on the same farm in July, at the beginning of the dry season, only 2 months later than in this second experimental series - the lethal dose for cattle was 2 g/kg. No explanation was found for the extremely high toxicity of the plant observed in the present study.
Abstract in Portuguese:
Oliveira C.M.C., Barbosa J.D., Macedo R.S.C., Brito M.F., Peixoto P.V. & Tokarnia C.H. 2004. [A comparative study of the toxicity of Palicourea juruana (Rubiaceae) to buffalo and cattle.] Estudo comparativo da toxidez de Palicourea juruana (Rubiaceae) para búfalos e bovinos. Pesquisa Veterinária Brasileira 24(1):27-30. Escola de Medicina Veterinária, Campus Castanhal, Universidade Federal do Pará, Rua Maximino Porpino 1000, Castanhal, PA 68743-080, Brazil. E-mail: tokarnia@ufrrj.br
An experimental study was performed to establish the toxicity of Palicourea juruana for buffaloes and to add new data on the toxicity of this plant for cattle. The clinical and pathological pictures were similar, but a comparison of the lethal doses for buffaloes (1-2g/kg) and cattle (0.25g/kg) shows that the buffalo is at least 4 times more resistant. In experiments performed 10 years earlier with the fresh leaves - collected on the same farm in July, at the beginning of the dry season, only 2 months later than in this second experimental series - the lethal dose for cattle was 2 g/kg. No explanation was found for the extremely high toxicity of the plant observed in the present study.
#4 - A toxidez de diversas lantanas para bovinos e ovinos no Brasil
Abstract in English:
Brito M.F., Tokarnia C.H. & Döbereiner J. 2004. [The toxicity of diverse lantanas for cattle and sheep in Brazil.] A toxidez de diversas lantanas para bovinos e ovinos no Brasil. Pesquisa Veterinária Brasileira 24(3):153-159. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23890-000, Brazil. E-mail: tokarnia@ufrrj.br
Experiments on the toxicity of Lantana spp for cattle and sheep revealed a similar situation as is reported from Australia. Neither all Lantana species nor all varieties which occur in Brazil are poisonous. Lantana samples collected at Boa Vista (Roraima), Castanhal (Pará), Cáceres (Mato Grosso), Serra Talhada (Pernambuco), Cabo Frio and Quatis (Rio de Janeiro), and Canoinhas (Santa Catarina) were toxic. All the other Lantana samples, collected at Cruzeiro do Sul (Acre), Castanhal (Pará), Chapada dos Guimarães and Lambari d’Oeste (Mato Grosso), Jaguaribe (Ceará), Vitória da Conquista and Wanderley (Bahia), Vitória (Espírito Santo), Vassouras, Parati and Itaguaí (Rio de Janeiro) revealed experimentally as non-toxic at a dose of 40g/kg. In all cases the lethal dose was 40 g/kg, with two exceptions: the sample collected at Canoinha (Santa Catarina) was much more toxic (10g/kg) and the one from Serra Talhada (Pernambuco) was much less toxic, as this last sample caused lethal poisoning only at a dosage of 40g/kg/day given during 30 days. Histories about the observation of photosensitization in cattle due to the ingestion of Lantana spp were obtained at Serra Talhada (Pernambuco), Cáceres (Mato Grosso), Cabo Frio and Quatis (Rio de Janeiro), and Canoinhas (Santa Catarina). No correlation could be established between the colour of the flowers of Lantana spp and the toxicity of the plants. This confirms reports from Australia that the toxic potential of the Lantana species is not necessarily related to the colour of their flowers.
Abstract in Portuguese:
Brito M.F., Tokarnia C.H. & Döbereiner J. 2004. [The toxicity of diverse lantanas for cattle and sheep in Brazil.] A toxidez de diversas lantanas para bovinos e ovinos no Brasil. Pesquisa Veterinária Brasileira 24(3):153-159. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23890-000, Brazil. E-mail: tokarnia@ufrrj.br
Experiments on the toxicity of Lantana spp for cattle and sheep revealed a similar situation as is reported from Australia. Neither all Lantana species nor all varieties which occur in Brazil are poisonous. Lantana samples collected at Boa Vista (Roraima), Castanhal (Pará), Cáceres (Mato Grosso), Serra Talhada (Pernambuco), Cabo Frio and Quatis (Rio de Janeiro), and Canoinhas (Santa Catarina) were toxic. All the other Lantana samples, collected at Cruzeiro do Sul (Acre), Castanhal (Pará), Chapada dos Guimarães and Lambari d’Oeste (Mato Grosso), Jaguaribe (Ceará), Vitória da Conquista and Wanderley (Bahia), Vitória (Espírito Santo), Vassouras, Parati and Itaguaí (Rio de Janeiro) revealed experimentally as non-toxic at a dose of 40g/kg. In all cases the lethal dose was 40 g/kg, with two exceptions: the sample collected at Canoinha (Santa Catarina) was much more toxic (10g/kg) and the one from Serra Talhada (Pernambuco) was much less toxic, as this last sample caused lethal poisoning only at a dosage of 40g/kg/day given during 30 days. Histories about the observation of photosensitization in cattle due to the ingestion of Lantana spp were obtained at Serra Talhada (Pernambuco), Cáceres (Mato Grosso), Cabo Frio and Quatis (Rio de Janeiro), and Canoinhas (Santa Catarina). No correlation could be established between the colour of the flowers of Lantana spp and the toxicity of the plants. This confirms reports from Australia that the toxic potential of the Lantana species is not necessarily related to the colour of their flowers.
#5 - Complementary studies on the toxicity of Lantana camara (Verbenaceae) in cattle, 19(3/4):128-132
Abstract in English:
ABSTRACT.- Tokarnia C.H., Armién A.G., Barros S.S., Peixoto P.V. & Döbereiner J. 1999. [Complementary studies on the toxicity of Lantana camara (Verbenaceae) in cattle.] Estudos complementares sobre a toxidez de Lantana camara (Verbenaceae) em bovinos. Pesquisa Veterinária Brasileira 19(3/4):128-132. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ, 23851-970, Brazil.
An outbreak of poisoning by Lantana camara var. aculeata in cattle was diagnosed in the county of Quatis, State of Rio de Janeiro. The animals, after travelling by foot, were put, hungry, for a few days, on a pasture highly infested by the plant. The toxicity of the plant was proved experimentally in cattle; also experiments to see how far the plant has cumulative properties, were performed. The plant caused Iethal poisoning when given as a single dose of 40 g/kg; 20 g/kg caused severe poisoning, 10 g/kg slight or no poisoning and 5 g/kg failed to provoke symptoms. A lethal result was produced also when 10 g/kg per day was given over 4 days. The administration of 5 g/kg per day caused severe poisoning when fed over 5 days to two calves. The dose of 2.5 g/kg fed daily over 7 or 9 days also produced severe poisoning in two calves; in another calf, severe symptoms were produced only after feeding 2.5 g/kg per day for 19 days; still another calf showed no symptoms after 32 days of feeding 2,5 g/kg per day, although twice the lethal dose had been fed by this time. A dose of 1.25 g/kg per day over . 34 days also failed to produce any symptoms.
Abstract in Portuguese:
RESUMO.- Tokarnia C.H., Armién A.G., Barros S.S., Peixoto P.V. & Döbereiner J. 1999. [Complementary studies on the toxicity of Lantana camara (Verbenaceae) in cattle.] Estudos complementares sobre a toxidez de Lantana camara (Verbenaceae) em bovinos. Pesquisa Veterinária Brasileira 19(3/4):128-132. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ, 23851-970, Brazil.
Descreve-se, no município de Quatis, RJ, a ocorrência de um surto de intoxicação por Lantana camara var. aculeata em bovinos, caracterizado por acentuada icterícia, lesões de fotossensibilização, constipação e edema subcutâneo dos membros. A reprodução experimental da doença, com êxito letal, através da administração de dose única de 40 g/kg de L. camara var. aculeata, confirmou a planta como causa do surto; doses únicas de 20 g/kg, 10 g/kg e 5 g/kg causaram respectivamente, grave intoxicação, leve intoxicação e ausência de sintomas. Experimentos com doses repetidas permitem concluir que essa planta apresenta efeito acumulativo, quando ingerida em doses diárias de 10 g/kg (1/4 da dose letal); a administração de quatro doses de 5 g/kg (1/8 da dose letal) ou de oito doses de 2,5 g/kg (1/16 da dose letal) reproduziram o quadro grave de intoxicação. Subdoses menores, de 1,25 g/kg (1/32 da dose letal), administradas durante 34 dias, não produziram quaisquer sinais clínicos. Os exames histológicos dos casos naturais e experimentais revelaram, além de bilestase, alterações regressivas nos hepatócitos e no epitélio dos túbulos renais.
#6 - Experiments on the to:xicity of some ornamental plants in cattle
Abstract in English:
Due to inquiries about the toxicity of ornamental plants to farm animals, and the few data available in the literature on this subject, feeding experiments were performed in cattle with the following plants: Allamanda cathartica, Nerium oleander and Tbevetia peruvíana of the Apocinaceae family, Codiaeum sp., Euphorbia cotinifolia, Euphorbia pulcherrima and Euphorbia tirucalli of the Euphorbiaceae family, Datura arborea of the Solanaceae family, Colocasia antiquoruni, Dieffenbachia picta, Monstera deliciosa, Philodendron hastatum, Philodendron selloum ( = P. sellowii) and Scindapsus aureus ( = Epipremnum aureum) of the Araceae family, Rhododendron ledifolium and Rhododendron indicum of the Ericaceae family, and Malvaviscus arboreus of the Malvaceae family. The only plants which caused lethal poisoning were Allamanda cathartica, Neríum oleander, Tbevetia peruviana and Rhododendron indicum. The letal dose for A. catártica was 30 g/kg (causing death of 2 of 3 bovines which received this dose), for N. oleanderit varied from 0,25 to 0,5 g/kg (0,25 killed 1 of 4 and 0,5 the 2 bovines which received this dose); T. peruviana caused death of 3 bovines with doses of 14,4 g/kg or more (out of 7 bovines which received these doses), and R. indicum caused death of the animal which received the highest dose which could be given, this is 29,39 g/kg, whilst a second bovine which received 29 g/kg suffered only severe poisoning. Other plants that caused severe poisoning without lethal outcome were Euphorbia pulcherríma, in doses of 16,4 and 30 g/kg, Rhododendron ledifolium in one bovine which ingested 20 g/kg, the highest dose of this plant administered. Moderate poisoning was caused by Datura arborea in one bovine which ingested 40 g/kg, by Colocasia antiquorum in 2 bovines which ingested 4 and 5,9 g/kg and by Dieffenbachia picta in 2 bovines, which ingested 3, 7 and 4,8 g/kg of the respective plants. The other plants did not cause poisoning or only slight symptoms. Allamanda cathartica caused mainly manifestations of colic and the most importante post-mortem and histopathological findings were severe oedema of all parts of the wall of the rumen and reticulum, and congestion of the mucosa of the remaining digestive tract. Nerium oleander caused severe cardiac arrhythmia and severe diarrhoea, sometimes with blood. The post-mortem findings were generalized hemorrhages and the main histological lesion was necrosis of heart fibres. Tbevetia peruviana also caused heart arrhythmia and diarrhoea. Post-mortem and histopathological findings were negative with exception of one of the bovines which had diarrhoea, in which the contents of the rumen were putrid and those of the intestine were liquid. Euphorbia pulchenima caused severe weakness. Datura arborea caused the symptoms of atropine poisoning. Rhododendron spp. caused mainly regurgitation without or with vomits, sialorrhoea, manifestations of colic, diarrhoea and instability. Post-mortem and histopathological findings in the only bovine that died, were negative. The plants of the Araceae family caused sialorrhoea and sublingual and submandibular oedema. It is concluded, that the rarity of the poisoning in cattle under natural conditions by these plants is due to its low palatability and the fact that normally these plants are not available to bovines, and yet that most of these plants have to oe ingested in large amounts to cause poisoning. An exception is Nerium oleander, whose lethal dose is low. It is practically the only ornamental plant of those tested in this study, which according to the data in the literature has caused cases of poisoning in cattle.
Abstract in Portuguese:
Em virtude de consultas sobre a toxidez de algumas plantas ornamentais em relação aos animais de fazenda, e os escassos dados na literatura sobre esse assunto, foram efetuados experimentos em bovinos com as seguintes plantas: Allamanda cathartica ("alamanda"), Nerium oleander ("espirradeira") e Thevetia peruviana ("chapeu-de-Napoleão") da família Apocinaceaé, Codiaeum sp. ("croton"), Euphorbia cotinifolia ("aiapana", "maleiteira"), Euphorbia pulchemma ("bico-de-papagaio") e Euphorbia tirucalli ("a veloz") da família Euphorbiaceae, Datura arborea ("trombeteira") da família Solanaceae, Colocasia antiquorum ("orelha-de-elefante"), Dieffenbachia picta ("comigo-ninguém-pode"), Monstera deliciosa ("costela-de-Adão"), Philodendron hastatum ("filodendron"), Philodendron selloum (=P sellowii) ("bananade-macaco") e Scindapsus aureus ( = Epipremnum aureum) ("jibóia, "jibóia-dourada") da família Araceae, Rhododendron ledifolium e Rhododedron indicum ("azaléia", "rododendron") da família Ericaceae, Malvaviscus arboreus ("papoula", "graxa-de-estudante", "chupetinha") da família Malvaceae. Verificou-se que as únicas plantas que causaram intoxicação grave com êxito letal, foram Allamanda cathartica, Nerium oleander, Tbevetia peruviana e Rhododendron indicum. A dose letal para A. cathartica foi de 30 g/kg, que matou 2 dos 3 bovinos que a receberam nesta dose, para N oleander foi de 0,25 a 0,5 g/kg (0,25 matou 1 de 4 e 0,5 g/kg os 2 bovinos que a receberam nessas doses); Tpenwiana causou a morte de 3 bovinos em doses a partir de 14,4 g/kg, entre 7 bovinos que a receberam nessas doses, e R. indicum causou a morte do bovino que ingeriu a maior dose que se conseguiu administrar, isto é 29,39 g/kg, enquanto um segundo que recebeu 29 g/kg adoeceu gravemente. Causaram intoxicação grave ainda, sem êxito letal, Euphorbia pulchemma, em doses de 16,4 e 30 g/kg, e Rhododendron ledifolium em um bovino que ingeriu 20 g/kg, a maior dose administrada desta planta. Intoxicação de intensidade moderada foi causada por Datura arbórea em um bovino que ingeriu 40 g/kg, por Colocasia antiquorum em 2 bovinos que ingeriram 4 e 5,9 g/kg e por Dieffenbachia picta em 2 bovinos que ingeriram 3,7 e 4,8 g/kg das respectivas plantas. As outras plantas não causaram intoxicação ou somente leves sintomas. Allamanda cathartica causou cólica como principal manifestação clínica e os achados de necropsia e histopatológicos mais importantes foram edema acentuado de todas as camadas da parede do rúmen e do retículo, além de congestão da mucosa do restante do tubo digestivo. Nerium oleander causou grave arritmia cardíaca e ainda acentuada diarréia, às vezes com sangue. Os achados de necropsia foram hemorragias generalizadas e a principal alteração histopatológica foi necrose de fibras cardíacas. Tbevetia peruviana também causou arritmia cardíaca e diarréia. Não foram verificadas alterações à necropsia e nos exames histopatológicos, a não ser em um dos bovinos que teve diarréia, em que o conteúdo do rúmen estava com cheiro pútrido e o de todo intestino estava líquido. Euphorbia pulchemma causou grande debilidade. Datura arborea causou sintomas de intoxicação por atropina. Rhododendron spp. provocaram principalmente regurgitamento sem ou com vômito, sialorréia, cólica, diarreia e perturbações de equilíbrio. Os achados de necropsia e histopatológicos no único bovino que morreu foram negativos. As plantas da família Araceae causaram sialorréia e edemas sublingual e submandibular. Conclui-se, que a raridade de casos de intoxicação por essas plantas, sob condições naturais em bovinos, deve estar ligada a dois fatores: à sua baixa palatabilidade e à falta de acesso dos bovinos a essas plantas de uma maneira geral, ainda mais que da maioria delas quantidades elevadas têm que ser ingeridas para causar quadro de intoxicação. Exceção constitui Nerium oleander; da qual doses pequenas das folhas já são letais. É praticamente a única planta ornamental das testadas nesse trabalho, sobre a qual há registros na literatura de casos de intoxicação natural em bovinos.
#7 - Factors which influence the toxicity of Baccharis coridifolia (Compositae): an experimental study in rabbits
Abstract in English:
Experimental studies were performed on Baccharis coridifolia D.C. (Compositae), a small shrub with the popular name "mio-mio", one of the more important poisonous plants of southern Brazil, Uruguay, Argentina and Paraguay, in arder to find out possible variations in toxicity due to its origin, sex, plant parts and annual variability. Doses which varied from 0.085 to 5.44 g/kg of the dried powdered aerial parts of B. coridifolia were administered in aqueous suspension by stomach tube to 49 adult rabbits. The plant material was collected in five different localities, from four sites in Brazil and one in Uruguay, in the flowering/seeding stage and separated by sex; in some regions collections were made in two successive years. From three of the sites additionally only the leaves of female plants were used for the experiments. Sixteen animals died and one that showed severe symptoms was euthanized together with the contral animal. Nineteen animals that showed slight to severe symptoms, recovered. First symptoms after the administration of the plant were seen, in the fatal cases from 6h32min to 1 day 6h15min, and in the non-fatal cases from 4h03min to 24h00min, after ingestion. The clinical course, in the fatal cases, varied from approximately 6h00min to 4 days 20h23min and, in the non-fatal cases, from 9h25min to 11 days 3h45min. The length of time from first administration of the plant till death varied from 14h20min to 5 clays 2h55min. The lethal dose varied from 0.17 to 5.44 g/kg. The main symptoms were anorexia, modifications in the form, size and consistency of the faeces and hair loss. The main post-mortem alterations were found in the stomach, caecum and liver. There was red colouration of the stomach mucosa. ln the caecum the surface of the mucosa was rough and red and the wall was oedematous. The liver was clearer than normal with perceptible lobulation. Histopathologically these lesions correspond to 1) coagulative necrosis associated with haemorrhages and oedema of the stomach mucosa, 2) haemorrhagic necrosis of the mucosa and oedema and/or haemorrhages of the submucosa of the caecum and 3) cloudy swelling and/or vacuolization of the liver. Greater toxicity of B. coridifolia was associated with more southerly sites of collection in Brazil. The female plant was up to 32 times more poisonous than the male plant; the whole aerial pa1ts of the plant were up to 16 times more poisonous when compared with only the leaves. There was up to a fourfold variation in toxicity from year to year. These differences can be explained by variations in the type and the amount of macrocyclic trichothecenes accumulated in the different parts of the plant, which are believed to be absorbed from the soil fungus Myrothecium verrucaria which produces them. B. coridifolia was compared with B. megapotamica var. weirii, which does not show these variations.
Abstract in Portuguese:
Foram realizados estudos experimentais com Baccharis coridifolia D.C. (Compositae), subarbusto, vulgarmente conhecido como "mio-mio", uma das plantas tóxicas mais importantes no sul do Brasil, Uruguai, Argentina e Paraguai, com a finalidade de verificar possíveis variações na sua toxidez de acordo com sua procedência, sexo, as diversas partes da planta e de um ano para outro. Foram administradas, a 49 coelhos adultos, em suspensão aquosa, via intragástrica, doses variando de 0,085 a 5,44 g/kg, das partes aéreas dessecadas e pulverizadas de B. coridifolia coletada em quatro procedências do sul do Brasil e uma do Uruguai, em floração/frutificação, separada por sexo e, de parte das regiões, em dois anos consecutivos; com a planta do sexo feminino de três destas procedências, realizaram-se, ainda, experimentos em que se administraram somente as folhas. Dezesseis animais morreram, um adoeceu acentuadamente sendo sacrificado junto com o controle e 19 adoeceram discreta a acentuadamente, recuperando-se. O prazo entre a administração da planta e o início dos sintomas, nos casos fatais, variou de 6h32min a 1 dia 6h15min e para os animais que sobreviveram, de 4h03min a 24h00min. A evolução clínica, nos casos fatais, variou de aproximadamente 6h00min. A 4 dias 20h23min e a recuperação, dos que sobreviveram, de 9h25min a 11 dias 3h45min. O prazo entre a administração da planta e a morte dos animais variou de aproximadamente 14h20min a 5 dias 2h55min. A dose letal variou de 0,17 a 5,44 g/kg. Os principais sintomas consistiram em anorexia, alteração na forma, tamanho e consistência das fezes e perda de pêlos. Os principais achados de necropsia ocorreram no estômago, ceco e fígado, consistindo em avermelhamento da mucosa estomacal, mucosa com superfície rugosa e de cor vermelha e edema da parede do ceco e fígado mais claro e com lobulação perceptível. Estas lesões corresponderam histopatologicamente à necrose de coagulação associada a hemorragias e edema da mucosa estomacal, à necrose hemorrágica da mucosa e edema e/ou hemorragia da submucosa do ceco e à tumefação e/ou vacuolização hepáticas. B. coridifolia mostrou-se mais tóxica quanto mais para o sul do Brasil; a planta feminina foi até 32 vezes mais tóxica do que a masculina; as partes aéreas da planta, folhas, flores e caule finos juntos, foram até 16 vezes mais tóxicas, quando comparadas com somente as folhas; mostrou-se com maior ou menor toxidez de um ano para outro, com diferença na dose letal de até quatro vezes. Tais variações podem ser explicadas por diferenças no tipo e quantidade de tricotecenos macrocíclicos acumulados nas suas diversas partes, que parecem ser absorvidos do fungo do solo Myrothecium verrucaria, que os produz. B. coridifolia foi comparada com B. megapotamica var. weirii, que não apresenta tais variações.
#8 - A comparative study on the toxicity of Lantana camara var. aculeata (Verbenaceae) in bovines and ovines
Abstract in English:
In experiments performed in 10 sheep the dried Lantana camara var. aculeata collected at Quatis, State of Rio de Janeiro, was shown not to have lost its toxicity at least up to one year after the plant had been harvested and kept in cloth sacs at room temperature, Both the fresh and the dried plant caused severe disease characterized by photosensitization and death of all animals at the dose of 40 g/kg, given at once; doses of 10 g/kg/day given during 4 following days, also caused severe disease of 4 out of 5 animals, but 2 of the severely diseased animals recovered. A comparison with the experimental poisoning in bovines with the plant collected from the sarne place showed that sheep were as sensible as caule, which are the main victims of the natural poisoning by L. camara. These experimental results are very useful for the survey on the toxicity of the many lantanas (species and taxa) which exist in Brazil, because samples of these plants may be collected in the different regions of Brazil independently of distance and difficulties in the ready performance of the experiments, and because sheep could be used instead of bovines in the experimentation.
Abstract in Portuguese:
Em experimentos realizados em 10 ovinos foi demonstrado que Lantana camara var. aculeata procedente do município de Quatis, no Estado do Rio de Janeiro, não perdeu em toxidez pela dessecagem e a manteve pelo menos durante um ano após a sua coleta, quando guardada em sacos de pano à temperatura ambiente. Tanto a planta fresca como a dessecada causaram doença grave com fotossensibilização e morte de todos os ovinos na dosagem única de 40 g/kg; a dosagem de 10 g/kg/dia durante 4 dias seguidos também causou doença grave em 4 dos 5 animais, mas 2 dos 4 animais severamente afetados se recuperaram. Uma comparação com a intoxicação experimental em bovinos com a planta da mesma procedência, mostrou que os ovinos têm a mesma sensibilidade que os bovinos, as principais vítimas da intoxicação natural por lantanas. Estes dados facilitarão o levantamento sobre a toxidez das muitas espécies e taxa de Lantana existentes no Brasil, pois permitem a coleta das amostras nas diversas regiões, independentemente de distâncias e dificuldades de pronta utilização, e o uso de ovinos em vez de bovinos na experimentação.
#9 - Experiments on the toxicity of some ornamental plants in sheep
Abstract in English:
For determinations of possible toxic effects of ornamental plants for sheep the following plant species were tested: Allamanda cathartica and Tbevetia peruviana of the Apocinaceae family, Codiaeum variegatum, Codiaeum sp., Euphorbia cotinifolia, Euphorbia pulcherrima and Euphorbia turucalli of the Euphorbiaceae family, Datura arborea of the Solanaceae family, and Caladium bicolor, Alocasia antiquorum, Dieffenbachia picta, Monstera deliciosa, Philodendron hastatum and Philodendron sp. of the Araceae family. The aerial parts without flowers or fruits of these plants were hand fed at the largest possible doses. In these amounts and under the conditions of these experiments the above mentioned plants did not cause or caused only slight non-specific symptoms of poisoning, with the exception of some species of the Araceae famliy, which provoked quite specific symptoms of moderate intensity.
Abstract in Portuguese:
Em função das dúvidas que se tem levantado sobre a toxidez de algumas plantas ornamentais para animais de fazenda, foram efetuados experimentos em ovinos, com as seguintes plantas: Allamanda catbartica ("alamanda") e Tbevetia peru.viana ("chapéu-de-Napoleão") da família Apocinaceae, Codiaeum variegatum ("cróton"), Codiaeum sp. ("cróton"), Euphorbia cotinifolia ("aiapana", "maleiteira"), Euphorbia pulcherrima ("bico-de-papagaio") e Euphorbia turucalli ("avelós") da família Euphorbiaceae, Datura arborea ("trombeteira") da família Solanaceae, e Caladium bicolor ("tajá", "tinhorâo", "coração-sangrento"), Alocasia antiquorum ("orelha-de-elefante"), Dieffenbachia picta ("comigo-ninguém-pode"), Monstera deliciosa ("costela-de-Adão"), Philodendron hastatum ("filodendron") e Philodendron sp. da família Araceae. A administração das partes aéreas frescas recém-coletadas sem flores e frutos dessas plantas foi feita manualmente, por via oral, nas maiores doses únicas possíveis. Verificou-se que as plantas nestas dosagens e condições não causaram sintomas de intoxicação ou apenas leves sintomas, não específicos, com exceção de algumas plantas da família Araceae, que produziram quadro clínico bastante típico, de intensidade moderada.
