PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Montanha F.P., Galeb L.A.G., Mikos J.D., Ganeco L.N., Pereira T.P., Tanaka A., Kirschnik P.G. & Pimpão C.T. 2012. Pyrethroid toxicity in silver catfish, Rhamdia quelen. Pesquisa Veterinária Brasileira 32(12):1297-1303. Laboratório de Pesquisa e Piscicultura, Pontifícia Universidade Católica do Paraná, Rodovia BR 376 Km 14, Bairro Costeira, São José dos Pinhais, PR 83010-500, Brazil. E-mail: chicopm28@yahoo.com.br This study aimed to determine both the lethal and sublethal concentrations of Cypermethrin in young Silver Catfish (Brazilian “Jundiá”, Rhamdia quelen) on aquatic environment during 96 hours, as well as to determine the Cypermethrin and Deltamethrin sublethal concentrations during the initial embryonic development period of Rhamdia quelen, and to verify their respective rates of fertilization, hatching and survival. Pyrethroid nowadays is a widely used insecticide, which presents a high toxicity to fish. In order to determine lethal and sublethal concentrations, 120 silver catfish were used; each one had an average weight of 59.58±4.50g and an average size of 20.33±2.34cm. Concentrations used were 0, 1.0, 1.5, 2.0, 2.5, 3.0, 5.0, 10.0, 15.0 and 20.0mg of Cypermethrin per liter of water (mg/L). Fish were exposed to the product in 30-liter fish tanks. In each fish tank there were four fishes and the product was applied three times, i.e., a total of twelve fish were exposed to the product at each application, and a total of 120 fish during the entire experiment (n=120). In order to determine the Cypermethrin and Deltamethrin sublethal concentrations during the initial embryonic development, ovulation induction was performed on female fishes using hormones, and then and egg collection was performed. The eggs were then hydrated and fertilized in Cypermethrin and Deltamethrin in different concentrations: 0.001, 0.01, 0.1, 1.0 and 10.0mg/L of Cypermethrin and 0.001, 0.01, 0.1, 0.5 and 1.0mg/L of Deltamethrin, in addition to the control group (0mg/L). After fertilization, the eggs were kept in containers with the respective pesticides of Cypermethrin and Deltamethrin until hatching, when hatching rate was verified. Then the alevins, from the hatching, were kept on their respective concentrations of Cypermethrin and Deltamethrin so that the survival rate could be analyzed regarding the tested insecticides, during both 12-hour and 24-hour periods. Concerning the sublethal and lethal concentrations, Silver Catfish was sensitive to the tested concentrations of Cypermethrin, showing symptoms of poisoning, such as loss of balance, swimming alteration, dyspnea (they kept their mouths and opercula open), upright swimming and sudden spiral swimming movements. The intensity of such symptoms varied in proportion to the concentration used. The concentrations above 3.0mg/L were considered lethal to the species, since every animal exposed to concentrations between 3.0 and 20.0mg/L had died, while concentrations between 1.0 and 2.5mg/L were considered sublethal. Lethal concentration of Cypermethrin to Silver catfish, in 96 hours, was 1.71 milligram per liter of water. Concerning the sublethal concentration of Cypermethrin and Deltamethrin during the initial embryonic development, the results show that both pyrethroids had significantly decreased the analyzed parameters when comparing them with the control group. It was concluded that, even with the fish being more resistant to pyrethroids in comparison with other species, both the young animals and the ones in stage of embryonic development were susceptible to the effects of these pesticides.

• Pyrethroid toxicity catfish Rhamdia quelen piretróides Jundiás Rhamdia quelen

Abstract in Portuguese:

RESUMO.- Montanha F.P., Galeb L.A.G., Mikos J.D., Ganeco L.N., Pereira T.P., Tanaka A., Kirschnik P.G. & Pimpão C.T. 2012. Pyrethroid toxicity in silver catfish, Rhamdia quelen. Pesquisa Veterinária Brasileira 32(12):1297-1303. Laboratório de Pesquisa e Piscicultura, Pontifícia Universidade Católica do Paraná, Rodovia BR 376 Km 14, Bairro Costeira, São José dos Pinhais, PR 83010-500, Brazil. E-mail: chicopm28@yahoo.com.br O presente estudo teve o objetivo de determinar a concentração letal e subletal da cipermetrina por via hídrica em 96 horas em jundiás (Rhamdia quelen) jovens, determinar a concentração subletal da cipermetrina e da deltametrina durante o período inicial do desenvolvimento embrionário do Rhamdia quelen e verificar suas respectivas taxas de fertilização, eclosão e sobrevivência. Os piretróides são inseticidas amplamente utilizados atualmente e apresentam alta toxicidade para peixes. Para determinação da concentração letal e subletal foram utilizados 120 jundiás com peso médio de 59,58±4,50g e comprimento médio de 20,33±2,34cm. As concentrações utilizadas foram 0; 1,0; 1,5; 2,0; 2,5; 3,0; 5,0; 10,0; 15,0 e 20,0mg de cipermetrina por litro de água (mg/L). Os peixes foram expostos ao produto dentro de aquários com capacidade para 30 litros. Em cada aquário foram colocados quatro peixes e cada tratamento teve três repetições, totalizando doze peixes por tratamento. Para determinar a concentração subletal da cipermetrina e deltametrina na fase de desenvolvimento embrionário foi realizada a indução da ovulação em fêmeas de jundiá através de hormônios, com posterior coleta dos ovos. Os ovos foram hidratados e fertilizados em soluções de cipermetrina e deltametrina em diferentes concentrações, sendo estas: 0,001; 0,01; 0,1; 1,0 e 10,0mg/L para cipermetrina e 0,001; 0,01; 0,1; 0,5 e 1,0mg/L para deltametrina, além do grupo controle (0mg/L). Após a fertilização, os ovos permaneceram em recipientes com os respectivos pesticidas até o momento da eclosão onde foi analisada a taxa de eclosão. Em seguida as larvas, a partir da eclosão dos ovos, foram mantidas nas respectivas concentrações de cipermetrina e deltametrina para analisar a taxa de sobrevivência frente aos inseticidas testados, durante 12 e 24 horas. Em relação as concentrações letais e subletais de jundiás jovens, estes apresentaram-se sensíveis à cipermetrina nas concentrações testadas, apresentando sinais de intoxicação como perda de equilíbrio, alteração na natação, dispnéia mantendo a boca e os opérculos abertos, nados verticais e movimentos súbitos de natação em forma de espiral. A intensidade destes sinais variou proporcionalmente a concentração utilizada. As concentrações acima de 3,0mg/L foram consideradas letais para a espécie em 96 horas, pois todos os animais expostos a concentrações entre 3,0 e 20,0mg/L vieram a óbito, enquanto que as concentrações entre 1,0 e 2,5mg/L são subletais. A CL50 96 horas da cipermetrina para o jundiá foi 1,71mg/L. Em relação aos efeitos da cipermetrina e deltametrina sobre a fase de desenvolvimento embrionário, os resultados mostraram que ambos os piretróides diminuíram significativamente os parâmetros analisados em comparação com o grupo controle. Conclui-se que mesmo o jundiá mostrando ser mais resistente aos piretróides em comparação com outras espécies, tanto animais jovens como animais em fase de desenvolvimento embrionário mostraram-se sensíveis aos efeitos destes pesticidas.

Abstract in English:

ABSTRACT.- Vilela S.M.O., Pinheiro Júnior J.W., Silva J.S.A., Pace F., Silveira W.D., Saukas T.N., Reis E.M.F. & Mota R.A. 2012. Research of Salmonella spp. and evaluation of pathogenicity, cytotoxicity of Escherichia coli isolates proceeding from sparrows (Passer domesticus). Pesquisa Veterinária Brasileira 32(9):931-935. Departamento de Medicina Veterinária, Universidade Federal Rural de Pernambuco, Rua Dom Manuel de Medeiros s/n, Recife, PE 52171-900, Brazil. E-mail: rinaldo.mota@hotmail.com The aim of this study was to research the occurrence of Salmonella spp. and Escherichia coli in feces samples of sparrows, as well as to identify the pathogenicity, cytotoxicity and sensitivity profile of the isolates to antimicrobial use. Two hundred and twenty eight sparrows were captured in eight farms. The in vitro pathogenicity test was performed by the isolates culture on congo red-magnesium oxalate Agar, whilst the in vivo pathogenicity test was performed in one day-old chicks. In order to study the cytotoxic effects of indicators, samples were inoculated into Vero cells. The results obtained for Escherichia coli isolation confirmed the presence of this microorganism in 30 (13.2%) of the evaluated samples. Out of those isolates, 10 (33.3%) presented the capacity of absorbing ongo red. As for in vivo pathogenicity a 68.0% of mortality rate of the evaluated samples was observed. Out of 20 isolates tested for cytotoxin production, none of them presented cytotoxic effect in the Vero cells. The Salmonella spp was isolated only in one sample (0.04%), and it was identified as Salmonella enterica subspecies houtenae. Results obtained through this research indicate the need for new studies to identify other virulence factors of E. coli samples and to delineate the phylogenetic profile of the isolates in order to establish a relation with colibacillosis outbreaks in chickens and broilers in the studied region, as well as to analyze the critical points in the aviculture productive chain to identify the source of Salmonella enterica subspecies houtenae.

• Salmonella spp. escherichia coli passer domesticus

Abstract in Portuguese:

RESUMO.- Vilela S.M.O., Pinheiro Júnior J.W., Silva J.S.A., Pace F., Silveira W.D., Saukas T.N., Reis E.M.F. & Mota R.A. 2012. Research of Salmonella spp. and evaluation of pathogenicity, cytotoxicity of Escherichia coli isolates proceeding from sparrows (Passer domesticus). Pesquisa Veterinária Brasileira 32(9):931-935. Departamento de Medicina Veterinária, Universidade Federal Rural de Pernambuco, Rua Dom Manuel de Medeiros s/n, Recife, PE 52171-900, Brazil. E-mail: rinaldo.mota@hotmail.com Objetivou-se com este estudo pesquisar a ocorrência de Salmonella spp. e Escherichia coli em amostras de fezes de pardais, além de avaliar a patogenicidade, citotoxicidade e perfil de sensibilidade dos isolados frente a antimicrobianos. Foram capturados 228 pardais em oito granjas. O teste de patogenicidade in vitro foi realizado por meio do cultivo dos isolados em ágar oxalato de magnésio acrescido de vermelho de congo, enquanto o teste de patogenicidade in vivo foi realizado em pintos de um dia. Para o estudo dos indicadores dos efeitos citotóxicos, as amostras foram inoculadas em células Vero. Os resultados obtidos quanto ao isolamento de Escherichia coli confirmaram a presença deste microorganismo em 30 (13,2%) amostras analisadas. Destes isolados, dez (33,3%) apresentaram capacidade de absorção do vermelho congo. Quanto à patogenicidade in vivo observou-se uma taxa de mortalidade de 68,0% das amostras analisadas. Dos 20 isolados testados quanto à produção de citotoxina, nenhum apresentou efeito citotóxico nas células Vero. Obteve-se o isolamento de Salmonella spp. em apenas uma amostra (0,04%), sendo tipificada em Salmonella enterica subespécie houtenae. Os resultados obtidos nesta pesquisa indicam a necessidade da realização de novos estudos para identificar outros fatores de virulência das amostras de E. coli e traçar o perfil filogenético dos isolados para estabelecer uma relação com surtos de colibacilose em galinhas e frango de corte na região estudada, além de analisar os pontos críticos na cadeia produtiva da avicultura para identificar a origem da Salmonella enterica subespécie houtenae.

Abstract in English:

ABSTRACT.- Raymundo D.L., Bezerra Jr P.S., Bandarra P.M., Dalto A.G.C., Soares M.P., Cruz C.E.F. & Driemeier D. 2012. Perreyia flavipes larvae toxicity. Pesquisa Veterinária Brasileira 32(8):735-738. Setor de Patologia Veterinária, Departamento de Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 95320-000, Brazil. E-mail: djeison.raymundo@dmv.ufla.br Fresh or thawed Perreyia flavipes larvae were ground and mixed with water and orally administered to sheep. At 5mg/kg, neither clinical nor enzymatic changes were observed. Unique doses of 7.5 and 10mg/kg induced characteristic clinical signs of Perreyia sp. larvae poisoning, increased GGT and AST values, and decreased glycemic curves. However, doses of 5, 10, and 15mg/kg repeated at 30 or 15 days intervals caused no disease and mild disease followed by death, respectively. These findings indicate that these animals probably developed some degree of tolerance to the toxins in P. flavipes larvae. Ultrastructural examination of liver revealed proliferation of the smooth endoplasmic reticulum in the hepatocytes, which may be associated with an increased ability to metabolize toxins and could consequently lead to the tolerance observed in the present study. Further investigations may elucidate whether such tolerance effects could be applied as a control measure for P. flavipes poioning or other hepatotoxic diseases. In addition, clinicopathological findings were discussed.

• Perreyia flavipes

Abstract in Portuguese:

RESUMO.- Raymundo D.L., Bezerra Jr P.S., Bandarra P.M., Dalto A.G.C., Soares M.P., Cruz C.E.F. & Driemeier D. 2012. Perreyia flavipes larvae toxicity. Pesquisa Veterinária Brasileira 32(8):735-738. Setor de Patologia Veterinária, Departamento de Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 95320-000, Brazil. E-mail: djeison.raymundo@dmv.ufla.br Larvas frescas ou descongeladas de Perreyia flavipes foram moídas e misturadas com água e administradas de forma oral a ovinos. Com 5mg/kg, não foram observados achados clínicos ou enzimáticos. Doses únicas de 7,5 e 10mg/kg induziram a sinais clínicos característicos de intoxicação pelas larvas de Perreyia sp., os níveis de GGT e AST estavam aumentados e as curvas glicêmicas estavam diminuídas. Entretanto, doses de 5, 10 e 15mg/kg repetidas em intervalos de 30 ou 15 dias não causou doença ou causou doença discreta seguida de morte, respectivamente. Estes achados indicam que estes animais provavelmente desenvolveram algum grau de tolerância para as toxinas presentes nas larvas de P. flavipes. O exame ultraestrutural do fígado revelou proliferação do retículo endoplasmático liso de hepatócitos, o que pode ser associado a um aumento na capacidade de metabolizar toxinas e conseqüentemente levar à tolerância observada no presente estudo. Outras investigações poderão esclarecer se os efeitos de tal tolerância poderiam ser aplicados como medida de controle da intoxicação por P. flavipes ou outras doenças hepatotóxicas. Além disso, os resultados clínico-patológicos foram discutidos.

Abstract in English:

ABSTRACT.- Ramírez-Duarte W.F., Rondón-Barragán I.S. & Eslava-Mocha P.R. 2008. Acute toxicity and histopathological alterations of Roundup® herbicide on “cachama blanca” (Piaractus brachypomus). Pesquisa Veterinária Brasileira 28(11):547-554. Insti-tuto de Acuicultura, Universidad de los Llanos, Apartado Aéreo 110, Km 4 vía Puerto López, vereda Barcelona, Villavicencio, Meta, Colombia. E-mail: wramirezduarte@yahoo.com.mx Acute toxicity of the glyphosate -N (phosphonomethyl) glycine- herbicide, Roundup®, in juveniles of cachama blanca, (Piaractus brachypomus), was evaluated and the histo-pathological lesions were assessed. The 96 h lethal concentration 50 was 97.47mg.L-1 (P<0.05). In the gill, necrotic and proliferative lesions were detected. In the liver, congestion, degenerative foci, hyaline droplets and lipidic vacuolization of the hepatocytes were observed. In the stomach mild hyperplasia of mucous cells was detected, which was also observed in the skin. In this latter tissue, a large increase in the thickness of the epidermis with necrotic lesions, infiltration of leukocytes and melanin pigment were observed. In the brain, degenerative foci of neuronal bodies in the telencephalon associated with gliosis and infiltration of eosinophilic granule cells/mast cells were shown. In conclusion, gills, liver, skin and brain are susceptible to Roundup®. Moreover, effects on the central nervous system could affect olfaction as well as individual and group behavior, the reproductive performance of the fish and hence have repercussions at the population level.

• Roundup® glyphosate acute toxicity histopathology Piaractus brachypomus

Abstract in Portuguese:

ABSTRACT.- Ramírez-Duarte W.F., Rondón-Barragán I.S. & Eslava-Mocha P.R. 2008. Acute toxicity and histopathological alterations of Roundup® herbicide on “cachama blanca” (Piaractus brachypomus). Pesquisa Veterinária Brasileira 28(11):547-554. Insti-tuto de Acuicultura, Universidad de los Llanos, Apartado Aéreo 110, Km 4 vía Puerto López, vereda Barcelona, Villavicencio, Meta, Colombia. E-mail: wramirezduarte@yahoo.com.mx Acute toxicity of the glyphosate -N (phosphonomethyl) glycine- herbicide, Roundup®, in juveniles of cachama blanca, (Piaractus brachypomus), was evaluated and the histo-pathological lesions were assessed. The 96 h lethal concentration 50 was 97.47mg.L-1 (P<0.05). In the gill, necrotic and proliferative lesions were detected. In the liver, congestion, degenerative foci, hyaline droplets and lipidic vacuolization of the hepatocytes were observed. In the stomach mild hyperplasia of mucous cells was detected, which was also observed in the skin. In this latter tissue, a large increase in the thickness of the epidermis with necrotic lesions, infiltration of leukocytes and melanin pigment were observed. In the brain, degenerative foci of neuronal bodies in the telencephalon associated with gliosis and infiltration of eosinophilic granule cells/mast cells were shown. In conclusion, gills, liver, skin and brain are susceptible to Roundup®. Moreover, effects on the central nervous system could affect olfaction as well as individual and group behavior, the reproductive performance of the fish and hence have repercussions at the population level.

Abstract in English:

ABSTRACT.- Araujo J.A.S., Riet-Correa F., Medeiros R.M.T., Soares M.P., Oliveira D.M. & Carvalho F.K.L. 2008. [Experimental poisoning by Ipomoea asarifolia (Convolvulaceae) in goats and sheep.] Intoxicação experimental por Ipomoea asarifolia (Convolvulaceae) em caprinos e ovinos. Pesquisa Veterinária Brasileira 28(10):488-494. Hospital Veterinário, CSTR, Campus de Patos, Universidade Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: franklin.riet@pq.cnpq.br Ipomoea asarifolia causes a tremogenic syndrome in sheep, goats, cattle and buffaloes. The objectives of the experiments were (1) to determine the toxicity to goats of fresh I. asarifolia collected during the raining and the dry season, and the toxicity of the dried plant, and (2) to determine the toxicity of the plant to sheep, and if the active principle is eliminated through the milk. In the first experiment the plant collected in the dry season and in the raining season was fed to 16 goats. The plant collected during the dry season caused clinical signs at the daily doses of 5g and 10g/kg body weight. The plant collected during the raining season was toxic at daily doses of 20g and 30g/kg, indicating that the plant is more toxic during the dry season. The plant collected in the dry season and dried was fed to 9 goats at doses of 1.7g, 2.0g, 3.4g, and 5.1g per kg. Daily doses of 3.0g, 4.0g and 5.1g/kg caused clinical signs, showing that the plant maintains its toxicity after being dried. In the second experiment the fresh plant collected in the dry and in the raining season was fed to 10 sheep. The plant collected in the dry season was toxic at the dose of 5g/kg, and the plant collected in the raining season was toxic at the doses of 10g and 20g/kg. The experimental results suggest that sheep are more susceptible to the poisoning than goats. As some farmers mentioned that suckling non-grazing lambs are poisoned by milk ingestion, I. asarifolia was fed at daily doses of 2.5g, 5.0g and 10g/kg for variable periods to 5 sheep from the day of parturition (2 sheep), after the last day of pregnancy (1 sheep) and 60 days before parturition (2 sheep). The sheep but not the lambs showed clinical signs of intoxication suggesting that the active principle is not eliminated through the milk at doses toxic for the lambs. In one euthanized sheep no gross or histologic lesions were detected. The main ultra-structural findings were found in Purkinje cell dendrites and included swelling, decrease or absence of dendritic spines, decrease or absence of neurotubules and neurofilaments and vacuolation of the dendroplasm. Swelling of the smooth endoplasmic reticulum and granular eletrondense inclusions in dendroplasm was observed. Swelling of astrocyte foot processes was conspicuous. It is suggested that these alterations are a result of continuous tremors induced by the plant with liberation of glutamate causing excitotoxicity, which probably constitutes a neuronal mechanism of defense.

• Toxic plants Ipomoea asarifolia goats sheep plant poisoning Purkinje cells swollen dendrites exitotoxicity tremogenic toxins

Abstract in Portuguese:

ABSTRACT.- Araujo J.A.S., Riet-Correa F., Medeiros R.M.T., Soares M.P., Oliveira D.M. & Carvalho F.K.L. 2008. [Experimental poisoning by Ipomoea asarifolia (Convolvulaceae) in goats and sheep.] Intoxicação experimental por Ipomoea asarifolia (Convolvulaceae) em caprinos e ovinos. Pesquisa Veterinária Brasileira 28(10):488-494. Hospital Veterinário, CSTR, Campus de Patos, Universidade Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: franklin.riet@pq.cnpq.br Ipomoea asarifolia causes a tremogenic syndrome in sheep, goats, cattle and buffaloes. The objectives of the experiments were (1) to determine the toxicity to goats of fresh I. asarifolia collected during the raining and the dry season, and the toxicity of the dried plant, and (2) to determine the toxicity of the plant to sheep, and if the active principle is eliminated through the milk. In the first experiment the plant collected in the dry season and in the raining season was fed to 16 goats. The plant collected during the dry season caused clinical signs at the daily doses of 5g and 10g/kg body weight. The plant collected during the raining season was toxic at daily doses of 20g and 30g/kg, indicating that the plant is more toxic during the dry season. The plant collected in the dry season and dried was fed to 9 goats at doses of 1.7g, 2.0g, 3.4g, and 5.1g per kg. Daily doses of 3.0g, 4.0g and 5.1g/kg caused clinical signs, showing that the plant maintains its toxicity after being dried. In the second experiment the fresh plant collected in the dry and in the raining season was fed to 10 sheep. The plant collected in the dry season was toxic at the dose of 5g/kg, and the plant collected in the raining season was toxic at the doses of 10g and 20g/kg. The experimental results suggest that sheep are more susceptible to the poisoning than goats. As some farmers mentioned that suckling non-grazing lambs are poisoned by milk ingestion, I. asarifolia was fed at daily doses of 2.5g, 5.0g and 10g/kg for variable periods to 5 sheep from the day of parturition (2 sheep), after the last day of pregnancy (1 sheep) and 60 days before parturition (2 sheep). The sheep but not the lambs showed clinical signs of intoxication suggesting that the active principle is not eliminated through the milk at doses toxic for the lambs. In one euthanized sheep no gross or histologic lesions were detected. The main ultra-structural findings were found in Purkinje cell dendrites and included swelling, decrease or absence of dendritic spines, decrease or absence of neurotubules and neurofilaments and vacuolation of the dendroplasm. Swelling of the smooth endoplasmic reticulum and granular eletrondense inclusions in dendroplasm was observed. Swelling of astrocyte foot processes was conspicuous. It is suggested that these alterations are a result of continuous tremors induced by the plant with liberation of glutamate causing excitotoxicity, which probably constitutes a neuronal mechanism of defense.

Abstract in English:

ABSTRACT.- Rozza D.B., Corrêa A.M.R., Leal J.S., Bandarra P.M., Guagnini F.S. & Djeison Lutier Raymundo D.L. & Driemeier D. 2007. [Experimental monensin poisoning in water buffaloes (Bubalus bubalis) and cattle.] Intoxicação experimental por monensina em búfalos e bovinos. Pesquisa Veterinária Brasileira 27(4):172-178. Departamento de Patologia Clínica Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br Monensin is widely used as a feed additive to improve performance of livestock; however accidental poisoning by this ionophore compound has been reported in a number of animal species. Typical clinical signs and lesions of monensin poisoning were induced in water buffaloes dosed with single dosages of 15, 10, 7.5, and 5mg/kg of the compound. Only buffaloes dosed with 2.5 mg/kg (1 day) and 1mg/kg (7 days) survived. Clinical signs initiated about 6 h post-dosing and included apathy, anorexia, diarrhea, drooling, muscular weakness, locomotion disorders, dyspnea, tachycardia, jugular distension and pulse, recumbency and death. The creatine kinase (CK) levels were highly augmented in blood samples of buffaloes dosed with monensin. Most prominent gross changes were ascites, hydrothorax, hydropericardium, cardiomegaly, hepatomegaly, and focal pale areas in the myocardium and in skeletal muscles. Degeneration and necrosis of myofibers were the principal histopathological findings. Conversely, no evidence of disease, neither change in CK levels were observed in the beef cattle steers dosed with same doses, confirming preliminary findings that buffaloes are more susceptible to monensin than cattle. In addition, this communication presents the minimal toxic dosage of monensin to buffaloes and suggests that CK tests may serve as health monitoring tools in the management of buffalo herds supplemented with monensin.

• Buffaloes cattle CK levels degenerative myopathy monensin toxicity monensin tolerance

Abstract in Portuguese:

ABSTRACT.- Rozza D.B., Corrêa A.M.R., Leal J.S., Bandarra P.M., Guagnini F.S. & Djeison Lutier Raymundo D.L. & Driemeier D. 2007. [Experimental monensin poisoning in water buffaloes (Bubalus bubalis) and cattle.] Intoxicação experimental por monensina em búfalos e bovinos. Pesquisa Veterinária Brasileira 27(4):172-178. Departamento de Patologia Clínica Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br Monensin is widely used as a feed additive to improve performance of livestock; however accidental poisoning by this ionophore compound has been reported in a number of animal species. Typical clinical signs and lesions of monensin poisoning were induced in water buffaloes dosed with single dosages of 15, 10, 7.5, and 5mg/kg of the compound. Only buffaloes dosed with 2.5 mg/kg (1 day) and 1mg/kg (7 days) survived. Clinical signs initiated about 6 h post-dosing and included apathy, anorexia, diarrhea, drooling, muscular weakness, locomotion disorders, dyspnea, tachycardia, jugular distension and pulse, recumbency and death. The creatine kinase (CK) levels were highly augmented in blood samples of buffaloes dosed with monensin. Most prominent gross changes were ascites, hydrothorax, hydropericardium, cardiomegaly, hepatomegaly, and focal pale areas in the myocardium and in skeletal muscles. Degeneration and necrosis of myofibers were the principal histopathological findings. Conversely, no evidence of disease, neither change in CK levels were observed in the beef cattle steers dosed with same doses, confirming preliminary findings that buffaloes are more susceptible to monensin than cattle. In addition, this communication presents the minimal toxic dosage of monensin to buffaloes and suggests that CK tests may serve as health monitoring tools in the management of buffalo herds supplemented with monensin.

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:

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.

• Poisonous plants plant poisoning photosensitization Lantana camara Verbenaceae pathology cattle Plantas tóxicas intoxicação por planta fotossensibilização patologia bovinos.

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.

Abstract in English:

Two outbreaks of Amaranthus spp. poisoning occurring in young pigs in Southern Brazil in late summer and early autumn are described. In both instances large amounts of freshly harvested Amaranthus spp. in its seeding stage were fed to the pigs. In one farm the Amaranthus was identified as A. viridis. Fourteen out of 25 pigs (56%) in one farm and 17 out of 100 07%) in another died. Clinical sigos included anorexia, depression, incoordinated gait; muscle stiffness, lateral recumbency, followed by death which occurred from 4 to 48 hours after clinical sigos were observed. Necropsy findings included perirenal edema and edema of other sites such as ascites; hydrotorax, hydropericardium, of the mesentery and the subcutaneous tissue of the ventral abdominal wall. The kidneys were pale and soft with subcapsular petechiae. In one of the three cases submitted for post-mortem examination there was marked edema of the renal papilla. Main histopathological findings were toxic tubular nephrosis affecting mainly the proximal convoluted tubules and mild tubular regeneration. In one case few refringent crystals were seen in the lumina of proximal tubules and in two cases the degenerative renal lesions were associated with moderate mononuclear interstitial inflitrate. Extra-renal lesions consisting of fibrinonecrotic glossitis and esophagitis were found in one pig and attributed to uremia.

• Poisonous plants Amaranthus viridis Amaranthaceae diseases of pigs pathology nephrotoxicity

Abstract in Portuguese:

São descritos dois surtos de intoxicação por Amaranthus spp. em suínos jovens no fim do verão e início do outono, no Estado do Rio Grande do. Sul. Em ambos os estabelecimentos onde ocorreram os surtos, os suínos eram alimentados com grandes quantidades de Amaranthus spp. em frutificação, recém-colhido. Em um dos estabelecimentos o Amaranthus foi identificado como A. viridis. No estabelecimento 1, morreram 14 suínos de um lote de 25 (56%) e no estabelecimento 2 morreram 17 de um total de 100 suínos (17%). Os sinais clínicos incluíam anorexia, apatia, andar incoordenado, rigidez muscular, decúbito lateral e morte, que ocorria de 4 a 48 horas após a observação dos sinais clínicos. Os achados de necropsia incluíam edema perirrenal e edemas em vários outros locais, como ascite, hidrotórax, hidropericárdio, mesentério e tecido subcutâneo da parede abdominal ventral. Os rins estavam pálidos e macios, com petéquias na superfície subcapsular. Em um caso havia marcado edema das papilas renais. Os principais achados histopatológicos foram nefrose tubular tóxica afetando principalmente os túbulos contorcidos proximais e regeneração tubular discreta. Em um dos três casos foram observados cristais refringentes na luz dos túbulos proximais e, em dois casos, as lesões renais degenerativas estavam associadas a moderado inflitrado mononuclear intersticial. Lesões extra-renais consistindo de glossite e esofagite fibrinonecróticas foram encontradas em um suíno e atribuídas à uremia.

• Plantas tóxicas Amaranthus viridis Amaranthaceae doenças de suínos patologia nefrotoxicidade

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.

• Poisonous plants experimental plant poisoning Baccharis coridifolia Compositae "mio-mio" pathology rabbit trichothecenes

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.

• Plantas tóxicas intoxicação experimental por plantas Baccharis coridifolia Compositae "mio-mio" patologia coelhos tricotecenos.