PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Maran N.B., Caldas S.A., Prado J.S., Gomes A.D., Tokarnia C.H. & Brito M.F. 2012. [Experimental poisoning of rabbits by Metternichia princeps (Solanaceae).] Intoxicação experimental por Metternichia princeps (Solanaceae) em coelhos. Pesquisa Veterinária Brasileira 32(9):872-880. Setor de Anatomia Patológica, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: marilene@ufrrj.br Metternichia princeps, a tree that belongs to the Solanaceae family, occurs in the Atlantic Forest of Brazil, from the state of Rio de Janeiro to Bahia. In the county of Itaguaí, state of Rio de Janeiro, M. princeps was suspected to cause a lethal kidney disease in goats. The poisoning was experimentally reproduced in goats confirming the suspicion. Experiments were then performed in rabbits. Leaves of M. princeps were collected in the county of Itaguaí, where the poisoning in goats occurred. Eleven rabbits received the dried plant material, ten received the fresh plant and one rabbit served as control. The dehydrated leaves were ground and mixed with water. Initially the suspension was administered by stomach tube to nine rabbits and caused death of seven of them at doses from 0.125g/kg on. Two rabbits that got sick, but survived at doses of 0.0625g/kg and 0.125g/kg, received doses of 0.5 and 0.25g/kg respectively, two months later and died, indicating that no tolerance to the plant poisoning effects developed. Additionally the dried leaves administered six months after collection to two rabbits at doses of 0.5 and 1g/kg respectively, caused death only of the rabbit that received the dose of 1g/kg, indicating that the stored leaves lost toxicity. Fresh sprouts caused death in three of six rabbits at doses of 1.55g/kg to 3g/kg. Fresh mature leaves caused death in one of four rabbits at the dose of 2g/kg, what suggests that there is no difference in toxicity between mature leaves and sprouts. The dried leaves caused death of rabbits at smaller doses than fresh leaves, what can be explained by the way of administration of the plant; dried leaves were given within a few minutes, whilst fresh leaves were ingested during one or two days, a fact that may influence absorption of the toxic principle. In all experiments with the dried and fresh leaves (sprouts and mature leaves) of M. princeps, liver and heart lesions predominated. The course of the poisoning was peracute to acute. The rabbits became apathetic with pale and cyanotic mucosae and cold ears; they fell down with struggling movements, vocalization and spaced breathing and died. At postmortem examination, the liver was pale with marked hepatic lobules; the other organs were congested and blood vessels were ingurgitated. The histopathological examination revealed as the more important changes in the liver, intense, especially centrilobular congestion, severe swelling of the hepatocytes, and foci of incipient necrosis of hepatocytes. In the heart, beside congestion, small groups of eosiophilic cardiac fibers, with nuclear picnosis and vacuolation were found. In the kidney, congestion and swelling of epithelial cells was seen. The performed experiments show that rabbits are susceptible to poisoning with dried and fresh leaves of M. princeps. It is suggested that the toxic principle of M. princeps, responsible for the clinical and pathological picture in rabbits, may not be the same compound that causes poisoning in goats or that the rabbit reacts differently as react goats; rabbits showed liver and heart lesions whilst goats had kidney lesions.

• Poisonous plants metternichia princeps solanaceae plantas tóxicas intoxicação

Abstract in Portuguese:

RESUMO.- Maran N.B., Caldas S.A., Prado J.S., Gomes A.D., Tokarnia C.H. & Brito M.F. 2012. [Experimental poisoning of rabbits by Metternichia princeps (Solanaceae).] Intoxicação experimental por Metternichia princeps (Solanaceae) em coelhos. Pesquisa Veterinária Brasileira 32(9):872-880. Setor de Anatomia Patológica, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: marilene@ufrrj.br Metternichia princeps, árvore que pertence à família Solanaceae, ocorre na Mata Atlântica desde o estado do Rio de Janeiro até a Bahia. É conhecida popularmente com os nomes de “café-do-mato”, “trombeteira” e “jasmin-do-morro”. Em um estabelecimento no município de Itaguaí, RJ, suspeitou-se que M. princeps era responsável por doença renal letal em caprinos. A intoxicação foi reproduzida experimentalmente nessa espécie, confirmando a suspeita. Foram então realizados experimentos em coelhos. Folhas de M. princeps foram coletadas no município de Itaguaí/RJ, local onde foi diagnosticada a intoxicação em caprinos. Onze coelhos receberam a planta dessecada, dez receberam a planta fresca e um coelho serviu como controle. As folhas dessecadas de M. princeps foram trituradas e misturadas com água. Inicialmente, a suspensão foi administrada por via intragástrica através de sonda a nove coelhos e causou a morte de sete coelhos nas doses a partir de 0,125g/kg. Dois coelhos que adoeceram mas sobreviveram às doses de 0,0625 e de 0,125g/kg, dois meses mais tarde receberam doses de 0,5 e 0,25g/kg, respectivamente, e morreram, o que indica que não houve desenvolvimento de tolerância à toxidez da planta. Adicionalmente, a planta dessecada, administrada a dois coelhos nas doses de 0,5 e 1g/kg seis meses após a coleta, causou a morte somente do coelho que recebeu a dose de 1g/kg, indicando que a planta armazenada perde em toxidez. Os brotos frescos causaram a morte de três dos seis coelhos, nas doses de 1,55g/kg a 3g/kg. As folhas maduras frescas causaram a morte de um dos quatro coelhos, na dose de 2g/kg, o que sugere que não há diferença na toxidez entre a brotação e as folhas maduras. As folhas dessecadas causaram a morte dos coelhos em doses menores que as folhas frescas, o que talvez possa ser explicado pelo modo de administração da planta; as folhas dessecadas eram administradas em poucos minutos, enquanto que as folhas frescas eram ingeridas durante um a dois dias, o que influenciaria a rapidez da absorção do princípio tóxico da planta. Tanto nos experimentos com as folhas dessecadas quanto com as folhas frescas (brotos e folhas maduras), predominaram no quadro clínico-patológico alterações relativas ao coração e ao fígado. A evolução da intoxicação foi superaguda a aguda. Os coelhos tornaram-se apáticos, com mucosas pálidas a cianóticas e orelhas frias, até que subitamente se debatiam na gaiola, faziam movimentos de pedalagem, vocalizavam, apresentavam acentuada dispneia e morriam. À necropsia, o fígado apresentava-se com evidenciação da lobulação; os demais órgãos estavam congestos e os vasos sanguíneos ingurgitados. À histopatologia, as lesões mais relevantes foram: no fígado, intensa congestão, especialmente centrolobular, tumefação acentuada dos hepatócitos e focos de necrose incipiente de hepatócitos; no coração, além de congestão, fibras cardíacas com aumento de eosinofilia, com picnose nuclear, fibras cardíacas com vacuolização, e no rim, congestão e tumefação de células epiteliais. Esses experimentos demonstram que o coelho é sensível à intoxicação pelas folhas dessecadas e frescas de M. princeps. Sugere-se que o princípio tóxico responsável pelo quadro clínico-patológico da intoxicação por M. princeps em coelhos não seja o mesmo princípio responsável pela intoxicação nos caprinos, ou que os coelhos reagem de maneira diferente dos caprinos; nos coelhos predominam alterações cardíacas e hepáticas enquanto que em caprinos as lesões são renais.

Abstract in English:

ABSTRACT.- Costa E.A., Bastianetto E., Vasconcelos A.C., Bomfim M.R.Q., Fonseca F.G., Gomes A.D., Leite R.C. & Resende M. 2009. An outbreak of malignant catarrhal fever in Murrah buffaloes in Minas Gerais, Brazil. Pesquisa Veterinária Brasileira 29(5):395-400. Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Belo Horizonte, MG 31270-901, Brazil. E-mail: lvc@icb.ufmg.br An outbreak of Malignant Catarrhal Fever (MCF) resulted in death of five female buffaloes and one domestic cow from the same farm. Four buffaloes died 10-15 days after the appearance of clinical signs, while the fifth was euthanized in extremis, after similar clinical signs. Histopathological lesions included multifocal histiolymphocytic epicarditis, myocarditis and lymphocytic interstitial pneumonia, which are commonly seen in cases of MCF in buffaloes. Furthermore, lymphocytic vasculitis centered in the adventitia, with occasional fibrinoid necrosis in the muscular layer, was found in the kidneys, liver, spleen, lymph nodes and brain. Nucleotide sequencing of DNA fragments from the central nervous system amplified by PCR revealed 98% similarity with known OHV-2 sequences from Genbank. Additionally, PCR analysis also revealed the presence of OHV-2 DNA in the peripheral mononuclear blood cells of two clinically healthy buffaloes. The diagnosis of MCF was based on epidemiological, clinical, gross and histopathological findings and on the results of a semi-nested PCR followed by nucleotide sequencing.

• Diseases of buffaloes doenças de búfalos gammaherpesviruses gammaherpesvirus malignant catarrhal fever

Abstract in Portuguese:

ABSTRACT.- Costa E.A., Bastianetto E., Vasconcelos A.C., Bomfim M.R.Q., Fonseca F.G., Gomes A.D., Leite R.C. & Resende M. 2009. An outbreak of malignant catarrhal fever in Murrah buffaloes in Minas Gerais, Brazil. Pesquisa Veterinária Brasileira 29(5):395-400. Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Belo Horizonte, MG 31270-901, Brazil. E-mail: lvc@icb.ufmg.br An outbreak of Malignant Catarrhal Fever (MCF) resulted in death of five female buffaloes and one domestic cow from the same farm. Four buffaloes died 10-15 days after the appearance of clinical signs, while the fifth was euthanized in extremis, after similar clinical signs. Histopathological lesions included multifocal histiolymphocytic epicarditis, myocarditis and lymphocytic interstitial pneumonia, which are commonly seen in cases of MCF in buffaloes. Furthermore, lymphocytic vasculitis centered in the adventitia, with occasional fibrinoid necrosis in the muscular layer, was found in the kidneys, liver, spleen, lymph nodes and brain. Nucleotide sequencing of DNA fragments from the central nervous system amplified by PCR revealed 98% similarity with known OHV-2 sequences from Genbank. Additionally, PCR analysis also revealed the presence of OHV-2 DNA in the peripheral mononuclear blood cells of two clinically healthy buffaloes. The diagnosis of MCF was based on epidemiological, clinical, gross and histopathological findings and on the results of a semi-nested PCR followed by nucleotide sequencing.

Abstract in English:

ABSTRACT.- Anjos B.L., Irigoyen L.F., Fighera R.A., Gomes A.D., Kommers G.D & Barros C.S.L. 2008. [Acute poisoning by bracken fern (Pteridium aquilinum) in cattle in central Rio Grande do Sul, Brazil.] Intoxicação aguda por samambaia (Pteridium aquilinum) em bovinos na Região Central do Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(10):501-507. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Cases of acute poisoning by bracken fern (Pteridium aquilinum) in cattle from 10 small farms of seven municipalities of the Central Region of Rio Grande do Sul State, Brazil, were reviewed. The study encompassed 6,256 necropsies of cattle considering a 43-year period and included 15 necropsies of cattle dying from acute bracken poisoning. Morbidity and mortality were 17.9% and lethality was virtually 100%. In 40% of the farms the disease occurred in small outbreaks affecting several cattle per farm and in 60% only one bovine was affected in each farm. Main clinical signs include fever (40-42°C), apathy, drooling, and hemorrhages; the latter were mainly from the gums, nostrils, and gastrointestinal tract. Multiple petechiae were observed in several mucosae and in the skin. Occasionally hematuria and blood in the milk were reported. The disease was invariably fatal after a course of approximately two days. Hematological changes included severe neutropenia, non-regenerative normocytic normochromic anemia and thrombocytopenia. Necropsy findings include hemorrhages o varying degrees in several organs and infarcts in the liver. Both hemorrhages and hepatic infarcts were confirmed histologically; clusters of bacterial rods and thrombosed vessels were associated with the infarcts. Marked bone marrow aplasia was a consistent finding in the four cases in which the marrow was evaluated.

• Diseases of cattle poisonous plants Pteridium aquilinum bracken fern hemorrhagic disorders pathology

Abstract in Portuguese:

ABSTRACT.- Anjos B.L., Irigoyen L.F., Fighera R.A., Gomes A.D., Kommers G.D & Barros C.S.L. 2008. [Acute poisoning by bracken fern (Pteridium aquilinum) in cattle in central Rio Grande do Sul, Brazil.] Intoxicação aguda por samambaia (Pteridium aquilinum) em bovinos na Região Central do Rio Grande do Sul. Pesquisa Veterinária Brasileira 28(10):501-507. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Cases of acute poisoning by bracken fern (Pteridium aquilinum) in cattle from 10 small farms of seven municipalities of the Central Region of Rio Grande do Sul State, Brazil, were reviewed. The study encompassed 6,256 necropsies of cattle considering a 43-year period and included 15 necropsies of cattle dying from acute bracken poisoning. Morbidity and mortality were 17.9% and lethality was virtually 100%. In 40% of the farms the disease occurred in small outbreaks affecting several cattle per farm and in 60% only one bovine was affected in each farm. Main clinical signs include fever (40-42°C), apathy, drooling, and hemorrhages; the latter were mainly from the gums, nostrils, and gastrointestinal tract. Multiple petechiae were observed in several mucosae and in the skin. Occasionally hematuria and blood in the milk were reported. The disease was invariably fatal after a course of approximately two days. Hematological changes included severe neutropenia, non-regenerative normocytic normochromic anemia and thrombocytopenia. Necropsy findings include hemorrhages o varying degrees in several organs and infarcts in the liver. Both hemorrhages and hepatic infarcts were confirmed histologically; clusters of bacterial rods and thrombosed vessels were associated with the infarcts. Marked bone marrow aplasia was a consistent finding in the four cases in which the marrow was evaluated.