PESQUISA VETERINÁRIA BRASILEIRA

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.

• Poisonous plants plant poisoning Lantana spp Verbenaceae sheep cattle pathology.

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.

Abstract in English:

Colodel E.M., Seitz A.L., Schmitz M., Borba M.R., Raymundo D.L. & Driemeier D. 2004. [Poisoning by Erythroxylum deciduum (Erythroxylaceae) in sheep.] Intoxicação por Erythroxylum deciduum (Erythroxylaceae) em ovinos. Pesquisa Veterinária Brasileira 24(3):165-168. Setor de Patologia Veterinária, Depto Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Cx. Postal 15094, Porto Alegre, RS 91540-000, Brazil. E- mail: moleta@terra.com.br. The epidemiological, clinical and pathological aspects of natural poisoning caused by Erythroxylum deciduum fruits in sheep are reported. The outbreak occurred from January to March of 2004, in Lagoa Vermelha county, state of Rio Grande do Sul, Brazil. The poisoning was experimentally reproduced by oral administration of E. deciduum fruits to 5 sheep.Three of them developed neurological signs and died. Poisoning was caused with a single dose of 60g/kg or when the dosage was fractioned into at least 4 doses of 17 g/kg given every 12 hours. The main clinical signs in natural and experimentally poisoned sheep were ataxia, hyperexcitability and muscular tremors which where more pronounced when the animals were moved. At the final stage, dyspnea with abdominal breathing and cyanosis was observed. The most significant alterations found at necropsy were pronounced edema, lung congestion and presence of the fruits or seeds of E. deciduum in the ruminal content of all animals. Histologically, except edema and pulmonary congestion, there were no other significant changes observed.

• Poisonous plants plant poisoning experimental plant poisoning Erythroxylum deciduum Erythroxylaceae sheep.

Abstract in Portuguese:

Colodel E.M., Seitz A.L., Schmitz M., Borba M.R., Raymundo D.L. & Driemeier D. 2004. [Poisoning by Erythroxylum deciduum (Erythroxylaceae) in sheep.] Intoxicação por Erythroxylum deciduum (Erythroxylaceae) em ovinos. Pesquisa Veterinária Brasileira 24(3):165-168. Setor de Patologia Veterinária, Depto Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Cx. Postal 15094, Porto Alegre, RS 91540-000, Brazil. E- mail: moleta@terra.com.br. The epidemiological, clinical and pathological aspects of natural poisoning caused by Erythroxylum deciduum fruits in sheep are reported. The outbreak occurred from January to March of 2004, in Lagoa Vermelha county, state of Rio Grande do Sul, Brazil. The poisoning was experimentally reproduced by oral administration of E. deciduum fruits to 5 sheep.Three of them developed neurological signs and died. Poisoning was caused with a single dose of 60g/kg or when the dosage was fractioned into at least 4 doses of 17 g/kg given every 12 hours. The main clinical signs in natural and experimentally poisoned sheep were ataxia, hyperexcitability and muscular tremors which where more pronounced when the animals were moved. At the final stage, dyspnea with abdominal breathing and cyanosis was observed. The most significant alterations found at necropsy were pronounced edema, lung congestion and presence of the fruits or seeds of E. deciduum in the ruminal content of all animals. Histologically, except edema and pulmonary congestion, there were no other significant changes observed.

Abstract in English:

Rech R.R, Fighera R.A., Oliveira F.N. & Barros C.S.L. 2004. [Granulomatous meningoencephalitis in cattle grazing vetch (Vicia spp).] Meningoencefalite granulomatosa em bovinos em pastoreio de ervilhaca (Vicia spp). Pesquisa Veterinária Brasileira 24(3): 169-172. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Granulomatous meningoencephalitis was observed in 7 out of 8 adult dairy cows affected by vetch-associated systemic granulomatous disease, although there was no neurological signs associated with the condition. The cellular inflammatory infiltrates were located in the leptomeninges and as perivascular cuffings within the brain and consisted of epithelioid macrophages, lymphocytes, plasm cells and eosinophils. These inflammatory changes varied from mild to severe from animal to animal and among different brain regions of the same animal. Perivascular cuffings were usually more marked than the leptomeningeal infiltrates. Affected brain regions, in decreasing order of intensity, included diencephalon through the level of massa intermedia, mesencephalon at the level of rostral colliculi, pons and cerebellar peduncles, medulla at the level of obex, frontal lobe at the level of the genu of the corpus callosum, and cerebellum. The character and the distribution of the inflammatory changes are emphasized regarding the differential diagnosis with other diseases and lesions of the bovine central nervous system in the context of the Brazilian surveillance program for bovine spongiform encephalopath.

• Diseases of cattle diseases of the central nervous system meningoencephalitis plant poisoning Vicia spp pathology.

Abstract in Portuguese:

Rech R.R, Fighera R.A., Oliveira F.N. & Barros C.S.L. 2004. [Granulomatous meningoencephalitis in cattle grazing vetch (Vicia spp).] Meningoencefalite granulomatosa em bovinos em pastoreio de ervilhaca (Vicia spp). Pesquisa Veterinária Brasileira 24(3): 169-172. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Granulomatous meningoencephalitis was observed in 7 out of 8 adult dairy cows affected by vetch-associated systemic granulomatous disease, although there was no neurological signs associated with the condition. The cellular inflammatory infiltrates were located in the leptomeninges and as perivascular cuffings within the brain and consisted of epithelioid macrophages, lymphocytes, plasm cells and eosinophils. These inflammatory changes varied from mild to severe from animal to animal and among different brain regions of the same animal. Perivascular cuffings were usually more marked than the leptomeningeal infiltrates. Affected brain regions, in decreasing order of intensity, included diencephalon through the level of massa intermedia, mesencephalon at the level of rostral colliculi, pons and cerebellar peduncles, medulla at the level of obex, frontal lobe at the level of the genu of the corpus callosum, and cerebellum. The character and the distribution of the inflammatory changes are emphasized regarding the differential diagnosis with other diseases and lesions of the bovine central nervous system in the context of the Brazilian surveillance program for bovine spongiform encephalopath.

Abstract in English:

Tokarnia C.H., Barbosa J.D., Oliveira C.M.C., Brito M.F., Oliveira R.B. & Barbas L.A. 2004. [Comparative epidemiological, clinical and pathological aspects of poisoning by Arrabidaea bilabiata (Bignoniaceae) in buffalo and cattle.] Aspectos epidemiológicos e clínico-patológicos comparados da intoxicação por Arrabidaea bilabiata (Bignoniaceae) em búfalos e bovinos. Pesquisa Veterinária Brasileira 24(2):74-79. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, Rio de Janeiro 23890-000, Brazil. E-mail: tokarnia@ufrrj.br Experiments showed that the clinical and pathological pictures were essentially the same, but the buffalo was at least twice more resistant than the bovine to the toxic effect of Arrabidaea bilabiata (Sprague) Sandw. It was also shown that the young leaves are twice (October, end of the dry season) or one and a half (May, end of the rainy season) more toxic than the mature leaves, and that the plant is more toxic in October. These data indicate that the smaller incidence of poisoning by plants of the group that causes sudden death in buffaloes in the Amazon Region is, in part, due to the greater resistance of this animal species to the toxic action of the plant. Also important seems to be the coincidence of the preferential habitat of the buffalo (flooded areas) with the habitat of A. bilabiata, less toxic than Palicourea marcgravii St.Hil. which is a plant of the non-flooded areas, the preferential habitat of cattle.

• Plant poisoning Arrabidaea bilabiata Bignoniaceae toxicity buffalo cattle.

Abstract in Portuguese:

Tokarnia C.H., Barbosa J.D., Oliveira C.M.C., Brito M.F., Oliveira R.B. & Barbas L.A. 2004. [Comparative epidemiological, clinical and pathological aspects of poisoning by Arrabidaea bilabiata (Bignoniaceae) in buffalo and cattle.] Aspectos epidemiológicos e clínico-patológicos comparados da intoxicação por Arrabidaea bilabiata (Bignoniaceae) em búfalos e bovinos. Pesquisa Veterinária Brasileira 24(2):74-79. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, Rio de Janeiro 23890-000, Brazil. E-mail: tokarnia@ufrrj.br Experiments showed that the clinical and pathological pictures were essentially the same, but the buffalo was at least twice more resistant than the bovine to the toxic effect of Arrabidaea bilabiata (Sprague) Sandw. It was also shown that the young leaves are twice (October, end of the dry season) or one and a half (May, end of the rainy season) more toxic than the mature leaves, and that the plant is more toxic in October. These data indicate that the smaller incidence of poisoning by plants of the group that causes sudden death in buffaloes in the Amazon Region is, in part, due to the greater resistance of this animal species to the toxic action of the plant. Also important seems to be the coincidence of the preferential habitat of the buffalo (flooded areas) with the habitat of A. bilabiata, less toxic than Palicourea marcgravii St.Hil. which is a plant of the non-flooded areas, the preferential habitat of cattle.

Abstract in English:

Cattani C.S.O., Colodel E.M., Traverso S.D., Correa A.M.R., & Driemeier D. 2004. [Experimental poisoning by Dodonea viscosa (Sapindaceae) in cattle.] Intoxicação experimental por Dodonea viscosa (Sapindaceae) em bovinos. Pesquisa Veterinária Brasileira 24(1):31-34. Depto Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Bairro Agronomia, Cx. Postal 15094, Porto Alegre, RS 91540-000, Brazil. E-mail: moleta@terra.com.br The leaves of Dodonea viscosa were force fed to five bovines. Four received the leaves in fresh green stage and the fifth dried ones. Clinical signs were observed in four of the bovines that died; the fifth did not show signs of poisoning. The fresh green plant was proved to be toxic from a dose of 25g/kg on. Dried leaves fed at the dose of 30 g/kg were also toxic. All the animals that died showed clinical signs from 13h30min to 45h after the ingestion of the plant and and death followed within about 48h. The clinical course lasted for about 8h30min until death. The main symptoms where apathy, anorexia, slight tenesmus, muscle trembling, difficulties to keep consciousness, pressing the head against obstacles, lateral recumbency, paddling movements, coma and death. The most significant macroscopic alterations were observed in the liver, with accentuation of the lobular pattern, dark-red areas interspersed with yellowish areas. Petechiae were found in serosal membranes of the abdominal and thoracic organs as well as the intestines. The main microscopic change was hepatic centrolobular coagulative necrosis, associated with congestion and hemorrhages.

• Dodonea viscosa diseases of cattle plant poisoning hepatocellular necrosis.

Abstract in Portuguese:

Cattani C.S.O., Colodel E.M., Traverso S.D., Correa A.M.R., & Driemeier D. 2004. [Experimental poisoning by Dodonea viscosa (Sapindaceae) in cattle.] Intoxicação experimental por Dodonea viscosa (Sapindaceae) em bovinos. Pesquisa Veterinária Brasileira 24(1):31-34. Depto Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Bairro Agronomia, Cx. Postal 15094, Porto Alegre, RS 91540-000, Brazil. E-mail: moleta@terra.com.br The leaves of Dodonea viscosa were force fed to five bovines. Four received the leaves in fresh green stage and the fifth dried ones. Clinical signs were observed in four of the bovines that died; the fifth did not show signs of poisoning. The fresh green plant was proved to be toxic from a dose of 25g/kg on. Dried leaves fed at the dose of 30 g/kg were also toxic. All the animals that died showed clinical signs from 13h30min to 45h after the ingestion of the plant and and death followed within about 48h. The clinical course lasted for about 8h30min until death. The main symptoms where apathy, anorexia, slight tenesmus, muscle trembling, difficulties to keep consciousness, pressing the head against obstacles, lateral recumbency, paddling movements, coma and death. The most significant macroscopic alterations were observed in the liver, with accentuation of the lobular pattern, dark-red areas interspersed with yellowish areas. Petechiae were found in serosal membranes of the abdominal and thoracic organs as well as the intestines. The main microscopic change was hepatic centrolobular coagulative necrosis, associated with congestion and hemorrhages.

Abstract in English:

ABSTRACT.- Bonel-Raposoj., Driemeier D., Barros S.S. & Gevehr~Fernandes C. 2003. [Histological and ultrastructural evolution of liver lesions in experimental Myoporum laetum poisoning of sheep and cattle.] Evolução das lesões histológicas e ultra-estruturais no fígado de ovinos e bovinos experimentalmente intoxicados por Myoporum laetum. Pesquisa Veterinária Brasileira 23(4):149-155. Depto Patologia Animal, Faculdade de Veterinária, UFPel, Pelotas, RS 96010-900, Brazil. E-mail: bonel-raposo@brturbo.com Green leaves of Myoporum laetum were collected during spring and summer, and administered to five sheep and six steers at dosages of 20 and 30 g/kg. Liver biopsies were taken before (Controls) and 1, 3 and 7 days after dosage. ln sheep, the clinicai signs were depression, rumen hypomotility, dried feces, tenesmus, teeth grinding, dyspnea and typical lesions of photosensitization. ln cattle, the clinicai picture was much less pronounced. The main histological findings in sheep were vacuolization of hepatocytes, portal ftbrosis, bile duct proliferation and necrosis of periportal hepatocytes; the ultrastructural examination revealed hyperplasia of the smooth endoplasmic reticulum, hepatocellular hydropic degeneration, presence of crystals and severa! other degenerative changes. ln cattle both, the histological and the ultrastructural findings, were less evident.

• Poisonous plants plant poisoning Myoporum laetum sheep cattle Plantas tóxicas intoxicação por plantas ovinos bovinos.

Abstract in Portuguese:

RESUMO.- Bonel-Raposoj., Driemeier D., Barros S.S. & Gevehr~Fernandes C. 2003. [Histological and ultrastructural evolution of liver lesions in experimental Myoporum laetum poisoning of sheep and cattle.] Evolução das lesões histológicas e ultra-estruturais no fígado de ovinos e bovinos experimentalmente intoxicados por Myoporum laetum. Pesquisa Veterinária Brasileira 23(4):149-155. Depto Patologia Animal, Faculdade de Veterinária, UFPel, Pelotas, RS 96010-900, Brazil. E-mail: bonel-raposo@brturbo.com Amostras de Myoporum laetum foram colhidas durante a primavera e verão e administradas a cinco ovinos e seis bovinos em doses únicas de 20 e 30 g/kg. Biópsias hepáticas foram colhidas antes (controles) e 1, 3 e 7 dias após a dosagem da planta. Estas biópsias foram analisadas histológica e ultraestruturalmente. Os sinais clínicos, em ovinos, caracterizaramse, especialmente; pordepressão, diminuição dos movimentos ruminais, fezes ressequidas, tenesmo, ranger de dentes, dispnéia e lesões típicas de fotossensibilização. Em bovinos, o quadro clínico foi discreto. Os principais achados histológicos, em ovinos, incluíram vacuolização de hepatócitos, fibrose portal, proliferação de duetos biliares e necrose de hepatócitos periportais. Os estudos ultra-estruturais, em ovinos, revelaram hiperplasia do retículo endoplasmático liso, tumefação de hepatócitos, degranulação e vesiculação do retículo endoplasmático rugoso, presença de cristais aciculares, retenção biliar, tumefação de mitocôndrias e várias outras alterações degenerativas. Em bovinos, tanto os achados histológicos, quanto os ultra-estruturais foram menos evidentes.

Abstract in English:

ABSTRACT.- Barbosa]. D., Oliveira C. M. C., Tokarnia C. H. & Riet-Correa E 2003. [Comparison of the sensibility of cattle and buffaloes to poisoning by Palicourea marcgravii (Rubiaceae).] Comparação da sensibilidade de bovinos e búfalos à intoxicação por Palicourea marcgravii (Rubiaceae). Pesquisa Veterinária Brasileira 23(4): 167-172. Escola de Medicina Veterinária, Campus Castanhal, Universidade Federal do Pará, Rua Maximino Porpino 1000, Castanhal, PA 68743- 080, Brazil. E-mail: diomedes@ufpa.br In order to verify if buffaloes are more resistant than cattle to poisoning by Palicourea marcgravii, the plant was given per os simultaneously to buffaloes and cattle. Seven buffaloes and three head of cattle were used. Doses of 0.5, 1.0 and 2.0 g/kg did not cause signs of poisoning in buffaloes; but doses of 3.0, 4.0 and 6.0 g/kg caused death. In cattle 0.25 g/kg did not cause symptoms; but 0.5 and 2.0 g/kg were lethal. The influence of exercise on the onset of symptoms, the time which elapsed from the beginning of the administration of the plant to the appearance of symptoms, and the symptoms themselves, were similar in the two animal species. The clinical course was longer in buffaloes; whilst in cattle the period between the onset of severe symptoms and death lasted 9 to 17 minutes; in buffaloes it varied from 10 minutes to 1 hour 28 minutes. It can be concluded, that buffaloes are about six times more resistant than cattle to the toxic action of P. maracgravii. The lower incidence of deaths in buffaloes by poisonous plants in the Amazon region is, at least in part, due the lower sensibility of buffaloes to poisoning by this plant. Another factor responsible for the smaller number of buffaloes which die due to plant poisoning in the Amazon region, is possibly that buffaloes prefer the Jowlands, e.g. temporarily flooded areas, which are the habitat of Arrabidaea bilabiata, the second most important poisonous plant of the Amazon region. This plant is less poisonous than P. marcgravii, and its habitat are the higher not flooded areas. So it would be safer, in order to diminish losses, to breed buffaloes instead of cattle in areas where P. marcgravii occurs. The reason for the greater resistance of buffaloes should be further investigated as a possible prophylactic measure to avoid poisoning by P. marcgravii in cattle. On the other hand, Australian investigators modified genetically the ruminai bacteria Butyrivibrio fibrisolvens by introducing a gene, isolated from a Moraxella sp, which codifies a dehalogenase, capable of hydrolyzing fluoroacetate, the poisonous principle of P. marcgravii. Transferring the genetically modified B. fibrisolvens into the rumen of animal, which consume plants that contain fluoroacetate, would be a viable method to control that poisoning through a ruminal detoxifying process for the toxin. Through preliminary contacts, the director of the consorcium in Australia, responsible for the modification of the bacteria, declared that he is interested to sell the technology to our country, but it would be necessary to know if it is permitted to introduce into Brazil the genetically modified bacteria. If allowed, it would be necessary to perform investigations on the viability and the methodology for using this bacteria to control P. marcgravii poisoning in our country.

• Poisonous plants plant poisoning Palicourea marcgravii Rubiaceae cattle buffaloes prophylaxis Butyrivibrio fibrisolvens genetically modified bactéria Intoxicação por planta Rubiaceae bovinos búfalos profilaxia bactérias geneticamente modificadas.

Abstract in Portuguese:

RESUMO.- Barbosa]. D., Oliveira C. M. C., Tokarnia C. H. & Riet-Correa E 2003. [Comparison of the sensibility of cattle and buffaloes to poisoning by Palicourea marcgravii (Rubiaceae).] Comparação da sensibilidade de bovinos e búfalos à intoxicação por Palicourea marcgravii (Rubiaceae). Pesquisa Veterinária Brasileira 23(4): 167-172. Escola de Medicina Veterinária, Campus Castanhal, Universidade Federal do Pará, Rua Maximino Porpino 1000, Castanhal, PA 68743- 080, Brazil. E-mail: diomedes@ufpa.br O presente estudo foi realizado para verificar se búfalos são mais resistentes do que bovinos à ação tóxica de Palicourea marcgravii, mediante a administração da planta por via oral, simultaneamente, a bovinos e a búfalos. Foram usados sete búfalos e três bovinos. Verificou-se que em búfalos doses de 0,5 g/kg, 1,0 g/kg e 2,0 g/kg não causaram sintomas de intoxicação. As doses de 3,0 g/kg, 4,0 g/kg e 6,0 g/kg causaram a morte dos búfalos. Em bovinos, a dose de 0,25g/kg não causou sinais clínicos de intoxicação, enquanto que doses de 0,5 g/kg e 2,0 g/kg causaram a morte. A influência do exercício sobre o aparecimento dos sintomas, o prazo decorrido desde o começo da administração da planta até o início de sintomas, e os próprios sintomas, foram semelhantes nas duas espécies animais. O curso clínico foi mais longo nos búfalos. Enquanto nos bovinos o período entre o aparecimento dos sintomas graves e a morte foi de 9 a 17 minutos, nos búfalos variou de 10 minutos a 1 hora e 28 minutos. Pode se concluir que os bubalinos são aproximadamente seis vezes mais resistentes do que os bovinos à ação tóxica de P. marcgravii. O menor índice de mortes pela ação de plantas tóxicas na Amazônia em búfalos é, pelo menos em parte, devido à maior resistência do búfalo à intoxicação por essa planta. Outro fator responsável pelo menor número de mortes em búfalos pela intoxicação por plantas, na Amazônia, poderia ser que os búfalos preferem a várzea, que é o habitat de Arrabidaea bilabiata, a segunda planta tóxica mais importante da Amazônia, menos tóxica do que P. marcgravii, e com habitat na terra firme. Em áreas onde ocorre P. marcgravii seria mais prudente, para diminuir os prejuízos, criar búfalos em lugar de bovinos. A causa dessa maior resistência do búfalo merece ser investigada para a eventual elaboração de métodos profiláticos da intoxicação por P. marcgravii em bovinos. Por outro lado, pesquisadores australianos modificaram geneticamente a bactéria ruminal Butyrivibrio fibrisolvens, mediante a introdução de um gene, isolado de Moraxella sp, que codifica uma dehalogenase, capaz de hidro-lizar fluoroacetato. A transferência de B.fibrisolvens geneticamente modificado para o rúmen de animais ingerindo plantas que contêm fluoroacetato, como é o caso de P. marcgravii, seria um método viável para o controle da intoxicação mediante a detoxificação ruminal do princípio ativo. Em contatos preliminares o diretor responsável do consórcio na Austrália responsável pela modificação da bactéria, declarou o interesse em vender a tecnologia ao nosso país, porém seria necessário saber se é possível importar essa bactéria geneticamente modificada no Brasil. Caso positivo, seria indispensável realizar pesquisas sobre a viabilidade e a metodologia para o uso dessa bactéria em nosso meio.

Abstract in English:

ABSTRACT.- Peixoto P.V., Brust L.A.C., Brito M.F., França T.N., Cunha B.R.M. & Andrade G.B. 2003. [Amaranthus spinosus (Amaranthaceae) poisoning in sheep in southern Brazil.] Intoxicação natural por Amaranthus spinosus (Amaranthaceae) em ovinos no Sudeste do Brasil. Pesquisa Veterinária Brasileira 23(4):179-184. Depto Nutrição Animal e Pastagem, Inst Zootecnia, UFRRJ, Seropédica, RJ 23835-000, Brazil. An outbreak of acute poisoning caused by Amaranthus spinosus is described in ewes of Southern Brazil. The clinical signs were characterized by uremic halitosis, loss of ruminal motility, dispnoea and abortion. Grossly in the kidneys there were pale red spots, white streaks extending from cortex to medulla, and congestion. Histologically there was a severe acute tubular nephrosis, dispersed foci of coagulative necrosis in the tiver, areas of coagulative necrosis in the myocardium and acute incipient interstitial pneumonia as well as secondary bronchopneumonia. Myocardial coagulative necrosis observed in seven sheep was attributed to hyperkalemia secondary to renal insufficiency. No references to spontaneous A. spinosus poisoning in sheep was found in the literature. Attempt to reproduce the poisoning by administration·of the plant to sheep was insuccessful, probably because A. spinosus used was not from fertilized areas.

• Poisonous plants plant poisononig Amaranthus spinosus Amaranthaceae sheep pathology Plantas tóxicas intoxicação por plantas ovino patologia.

Abstract in Portuguese:

RESUMO.- Peixoto P.V., Brust L.A.C., Brito M.F., França T.N., Cunha B.R.M. & Andrade G.B. 2003. [Amaranthus spinosus (Amaranthaceae) poisoning in sheep in southern Brazil.] Intoxicação natural por Amaranthus spinosus (Amaranthaceae) em ovinos no Sudeste do Brasil. Pesquisa Veterinária Brasileira 23(4):179-184. Depto Nutrição Animal e Pastagem, Inst Zootecnia, UFRRJ, Seropédica, RJ 23835-000, Brazil. No Estado do Rio de janeiro descreve-se um surto de intoxicação aguda por Amaranthus spinosus em 12 ovelhas, caracterizado clinicamente por hálito urêmico, ausência de movimentos ruminais, dispnéia e aborto. Os animais foram colocados em um pasto adubado e severamente invadido pela planta. A necropsia realizada em seis ovinos revelou rins pálidos, em geral, com estriações esbranquiçadas desde o córtex até a medula; em um animal verificaram-se diversos infartos sob forma de figuras geométricas no córtex. O fígado apresentava-se mais claro, por vezes com lobulação evidente. Em um animal verificaram- se áreas pálidas no miocárdio. Os pulmões congestos, algo mais pesados e consistentes, por vezes evidenciavam áreas de hepatização vermelha e cinzenta na porção cranial. Petéquias, equimoses e sufusões foram observadas em serosas, na mucosa do tubo digestório e em outros órgãos. Ao exame histológico verificaram-se acentuada nefrose tubular tóxica, focos aleatórios de necrose coagulativa no fígado, áreas de necrose coagulativa no miocárdio e pneumonia intersticial aguda incipiente acompanhada por áreas de broncopneumonia. Na literatura não foram encontradas referências à intoxicação natural por A. spinosus em ovinos. Tentativas de reprodução da intoxicação coma planta em ovinos, não foram bem sucedidas, provavelmente porque, nos experimentos, não se utilizou A. spinosus proveniente de áreas adubadas. A necrose do miocárdio encontrada, ao exame microscópico do coração de diversos animais foi atribuída a hipercalemia secundária à insuficiência renal, ao passo que a gênese dos infartos renais verificados em um ovino permanece obscura.

Abstract in English:

ABSTRACT.- Duarte M.D., Peixoto P. V., Bezerra P. S., Oliveira K. D., Loretti A. P. & Tokarnia C.H. 2003. [Natural and experimental poisoning by amitraz in horses and donkey: Clinical aspects.) Intoxicações natural e experimental por amitraz em eqüídeos: aspectos clínicos. Pesquisa Veterinária Brasileira 23(3):105-118. Hospital Veterinário, Setor Grandes Animais, Universidade Federal Rural do Rio de Janeiro, Seropédica. RJ 23835-000, Brazil. E-mail: marcos @webcem.com.br Poisoning by amitraz was experimentally reproduced in 17 horses and a donkey. First symptoms were observed between 15 min. and 2 h 5 min. after oral administration, and between 6 h 28 min. and 8 h 38 min. after spraying with amitraz. The course of poisoning after oral administration was 4 to 9 days, and after spraying 5 to 6 days. Death of experimental animais occurred only after oral administration. One animal was euthanized after spraying. Doses of 5.5 mg/kg (1 administration), 5.8 mg/kg (2 administrations) and doses which varied between 7.2 and 36.4 mg/kg (5 administrations) were used when amitraz was given by mouth, ali causing symptoms of poisoning. When the administration of amitraz was by spraying, poisoning was reproduced with solutions of 0.1 and 0.2 %. Regarding the nervous system, the main signs observed were recumbency, somnolence, palpebral and auriculár ptosis, difficulties in apprehension, chewing and swallowing of food, dragging of the hooves, exposure of the penis, diminished or absent cutaneous sensibility, instability, abduction of the legs, lowering of the head, incoordination, jawning, labial flacity, exposure of the tongue, crossing of the legs when walking, diminished postural response after crossing or abducting the legs, diminished/absent reflex of the upper lip, palatal, tongue, flexor and swallowing reflex, diminished auricular, palpebral and menace reflex. The ambulatory response was diminished when tested by walking in circles of small radius. Regarding the digestive system, the signs were mainly intestinal hypomotility/atony, edema of the lips, abdominal distention, frequente lying down and standing up, rolling on the ground, looking at the flancs, groaning and impaction of the large bowel. Regarding the circulatory system, the main clinical signs were tachycardia, increase of the refilling time of capillaries, congested mucosa and splitting of the cardiac sounds. Regarding the respiratory system, stridor, tachypnoea, dyspnoea, nasal discharge, bradypnoea and abdominal respiration was observed. Beside these signs, there were alterations of the general condition, as apathy and hypothermia. Ali natural cases occurred after spraying with amitraz. First symptoms were seen 2 to 3 days after the application of amitraz. The course was 6, 7 and 17 days. One animal showed mainly the nervous signs as seen in the experiments, with exception of the signs of crossing the legs when walking, yawning and exposure of the penis. Another animal had only digestive symptoms as rolling, pawing, intestinal hypomotility/atony and impaction of the large bowel. A third animal initially showed digestive symptoms characterized by pawing, rolling, intestinal atony and impaction of the Iarge bowel, followed by laminitis; in the final stage this animal showed severe nervous signs as pressing the head against obstacles, incoordination with crossing the legs when walking and reluctance to move. Possible Iocation of lesions in the nervous system according to the clinical signs are suggested.

• Poisoning horses donkey amitraz Intoxicações eqüídeos amitraz.

Abstract in Portuguese:

RESUMO.- Duarte M.D., Peixoto P. V., Bezerra P. S., Oliveira K. D., Loretti A. P. & Tokarnia C.H. 2003. [Natural and experimental poisoning by amitraz in horses and donkey: Clinical aspects.) Intoxicações natural e experimental por amitraz em eqüídeos: aspectos clínicos. Pesquisa Veterinária Brasileira 23(3):105-118. Hospital Veterinário, Setor Grandes Animais, Universidade Federal Rural do Rio de Janeiro, Seropédica. RJ 23835-000, Brazil. E-mail: marcos @webcem.com.br A administração oral e a aspersão com amitraz reproduziram experimentalmente em 17eqüinos e uin asinino um quadro de intoxicação muito similar a outro que vinha ocorrendo em cavalos no Estado do Rio de Janeiro. O início dos sintomas após a administração oral variou entre 15min. e 2h05min., na aplicação por aspersão variou entre 6h28min. e 8h38min. A evolução nos casos de administração oral foi de 4 a 9 dias, nos de aspersão de 5 a 6 dias. Somente morreram animais que receberam a administração oral. Um animal aspergido com o amitraz foi sacrificado. Por via oral foram usadas dosagens de 5,5 mg/kg (uma administração), 5,8 mg/kg (duas administrações) e num terceiro animal, doses que variaram entre 7,2 e 36,4 mg/kg (cinco administrações). Nas aplicações por aspersão, a intoxicação foi reproduzida com soluções nas concentrações de O, 1 e 0,2%. Com relação ao sistema nervoso, os principais sinais observados foram apatia, sonolência, ptoses palpebral e auricular, dificuldade de apreensão, mastigação e· deglutição do alimento, arrastar das pinças dos cascos no solo, exposição do pênis, sensibilidade cutânea diminuída/ausente, instabilidade em estação, abdução dos membros, cabeça baixa, incoordenação, bocejos, flacidez labial, exposição da língua, cruzamento dos membros ao caminhar, resposta postural diminuída após cruzar e abduzir os membros, reflexos do lábio superior, palatal, lingual, de deglutição e flexor diminuídos/ausentes, reflexos auricular, palpebral e de ameaça diminuídos e resposta ambulatória diminuída ao teste de girar em círculo de pequeno raio. No que se refere ao sistema digestivo, foram evidenciados, principalmente, hipomotilidade/atonia intestinal, edema dos lábios, distensão abdominal, deitar e levantar com freqüência, rolar no solo, olhar para o flanco, gemer e impactação do intestino grosso. Observaram-se ainda taquicardia, aumento do tempo de preenchimento capilar e mucosas congestas, estridor, taquipnéia, dispnéia, secreção nasal, bradipnéia e respiração abdominal. Todos os três casos naturais ocorreram após aspersão do amitraz. Os primeiros sintomas foram observados 2 e 3 dias após o banho. A evolução foi de 6, 7 e 17 dias. Um animal manifestou a maioria dos sinais referentes ao sistema nervoso observados nos experimentos, com exceção dos sinais de cruzamento dos membros ao caminhar, bocejos, lábios flácidos e exposição do pênis. Outro animal, intoxicado espontaneamente, manifestou somente sintomas digestivos como rolar, "patear", hipomotilidade/atonia intestinal e impactação do intestino grosso. Um terceiro animal, inicialmente manifestou sintomas digestivos caracterizados por patear, rolar, atonia intestinal e impactação do intestino grosso, com consequente desenvolvimento de laminite; na fase final exibiu acentuada sintomatologia nervosa mostrando compressão da cabeça contra obstáculos, incoordenação motora com cruzamento dos membros ao caminhar e relutância em se movimentar. Baseados no quadro clínico observado, são sugeridos possíveis locais de lesão no sistema nervoso.

Abstract in English:

ABSTRACT.- Medeiros R.M.T., Riet-Correa F., Tabosa I.M., Silva Z.A., Barbosa R.C., Marques A.V.M.S. & Nogueira F.R.B. 2003. [Nitrate and nitrite poisoning in cattle caused by the ingestion of Echinochloa polystachya and Pennisetum purpureum in the semiarid region of the state of Paraíba.] Intoxicação por nitratos e nitritos em bovinos por ingestão de Echinochloa polystachya (capim-mandante) e Pennisetum purpureum (capim-elefante) no sertão da Paraíba. Pesquisa Veterinária Brasileira 23(1):17-20. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, PB, Brazil. E-mail: rmtmed@cstr.ufpb.br Three outbreaks ofnitrate poisoning are reported from the semiarid region ofthe state of Paràíba, northeastem Brazil. One outbreak caused by Echinochloa polystachya (capim-mandante) and two others caused by Pennisetum purpureum (capim-elefante) occurred at the end ofthe dry season, after the first raios. ln one ofthe outbreaks caused by Pennisetum purpureum part of the pasture had been fertilized with cattle manure. Five out of 11 cattle died on one farm, 27 out of81 on another, and 3 out of9 on a third one. Clinicai sigos were anorexia, respiratory distress, teeth grinding, depression or hyperexitability, tremors, abdominal contractions, salívation, nasal discharge, uncoordinated gait, cyanosis, and finally recumbency. Nitrates and nitrites in the blood of affected cattle and pastures were determined by the diphenylamine test. It is suggested that the main reason for nitrate accumulation in the grasses was the prolonged draught followed by rain. ln one ofthe outbreaks caused by Pennisetum purpureum, another reason was probably the fertilization of the soil with cattle manure.

• Nitrate poisoning Echinochloa polystachya Pennisetum purpureum capim-elefante capim-mandante Intoxicação por nitratos.

Abstract in Portuguese:

RESUMO.- Medeiros R.M.T., Riet-Correa F., Tabosa I.M., Silva Z.A., Barbosa R.C., Marques A.V.M.S. & Nogueira F.R.B. 2003. [Nitrate and nitrite poisoning in cattle caused by the ingestion of Echinochloa polystachya and Pennisetum purpureum in the semiarid region of the state of Paraíba.] Intoxicação por nitratos e nitritos em bovinos por ingestão de Echinochloa polystachya (capim-mandante) e Pennisetum purpureum (capim-elefante) no sertão da Paraíba. Pesquisa Veterinária Brasileira 23(1):17-20. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, PB, Brazil. E-mail: rmtmed@cstr.ufpb.br Descrevem-se três surtos de intoxicação por nitratos e nitritos em bovinos na região semi-árida do estado da Paraíba, nordeste do Brasil. O primeiro surto foi causado por Echinochloa polystachya (capim-mandante) e os demais por Pennisetum purpureum (capim-elefante) e ocorreram após um período prolongado de seca, após o início das primeiras chuvas. Em um dos surtos causado por Pennisetum purpureum, uma parte da área onde estava o pasto que continha níveis altos de nitratos havia sido fertilizada com esterco de bovino. No primeiro surto morreram 5 bovinos de um total de 11, no segundo morreram 21 de um total de 81 e no terceiro morreram 3 de um total de 19 bovinos. Os sinais clínicos se caracterizaram por anorexia, dispnéia, ranger de dentes, depressão ou hiperexitabilidade, tremores, contrações abdominais, salivação, corrimento nasal, andar cambaleante, mucosas cianóticas e, finalmente, decúbito. A presença de nitratos e nitritos foi detectada no sangue dos animais e nos pastos por meio da prova de difenilamina. Parece que o principal fator que determinou a concentração de altos níveis de nitratos nas plantas foi a ocorrência de chuvas depois de um longo período de seca. Outro fator importante no surto causado por Pennisetum purpureum foi a fertilização do solo com esterco.