PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Antoniassi N.A.B., Ferreira E.V., Santos C.E.P., Campos J.L.E., Nakazato L. & Colodel E.M. 2007. [Spontaneous Ipomoea carnea subsp. fistulosa (Convolvulaceae) poisoning of cattle in the Brazilian Pantanal.] Intoxicação espontânea por Ipomoea carnea subsp. fistulosa (Convol-vulaceae) em bovinos no Pantanal Matogrossense. Pesquisa Veterinária Brasileira 27(10):415-418. Departamento de Clínica Médica Veterinária, Faculdade de Agronomia e Medicina Veterinária, Universidade Federal de Mato Grosso, Cuiabá, MT 78068-900, Brazil. E-mail: moleta@ufmt.br A spontaneous Ipomoea carnea subsp. fistulosa (canudo, algodoeiro) poisoning of cattle in the county of Poconé, Brazilian Pantanal, is reported. The investigation began after 12 cattle had died from a flock of 500 animals maintained in an extensive area intensely infested by I. carnea subsp. fistulosa with scarce availability of other fodder plants. The deaths occurred from June to September of 2006. Clinical signs were loss of weight and neurological deficits with hypermetry and incoordination. No significant gross lesions were observed at postmortem examination of one bovine. Histological changes comprised widespread cytoplasmic vacuolation of neurons, cells of the thyroid, kidney and pancreas. Cattle with similar clinical picture, that had been removed from the area invaded by I. carnea subsp. fistulosa and placed into areas with native and Brachiaria sp. pasture, recovered clinically within 15 days.

• Poisonous plants Ipomoea carnea subsp. fistulosa plant poisoning storage diseases cattle

Abstract in Portuguese:

ABSTRACT.- Antoniassi N.A.B., Ferreira E.V., Santos C.E.P., Campos J.L.E., Nakazato L. & Colodel E.M. 2007. [Spontaneous Ipomoea carnea subsp. fistulosa (Convolvulaceae) poisoning of cattle in the Brazilian Pantanal.] Intoxicação espontânea por Ipomoea carnea subsp. fistulosa (Convol-vulaceae) em bovinos no Pantanal Matogrossense. Pesquisa Veterinária Brasileira 27(10):415-418. Departamento de Clínica Médica Veterinária, Faculdade de Agronomia e Medicina Veterinária, Universidade Federal de Mato Grosso, Cuiabá, MT 78068-900, Brazil. E-mail: moleta@ufmt.br A spontaneous Ipomoea carnea subsp. fistulosa (canudo, algodoeiro) poisoning of cattle in the county of Poconé, Brazilian Pantanal, is reported. The investigation began after 12 cattle had died from a flock of 500 animals maintained in an extensive area intensely infested by I. carnea subsp. fistulosa with scarce availability of other fodder plants. The deaths occurred from June to September of 2006. Clinical signs were loss of weight and neurological deficits with hypermetry and incoordination. No significant gross lesions were observed at postmortem examination of one bovine. Histological changes comprised widespread cytoplasmic vacuolation of neurons, cells of the thyroid, kidney and pancreas. Cattle with similar clinical picture, that had been removed from the area invaded by I. carnea subsp. fistulosa and placed into areas with native and Brachiaria sp. pasture, recovered clinically within 15 days.

Abstract in English:

ABSTRACT.- Lucioli J., Furlan F.H., Mezaroba S., Traverso S. D. & Gava A. 2007. [Spontaneous and experimental poisoning by Eupatorium tremulum (Asteraceae) in cattle.] Intoxicação espon-tânea e experimental por Eupatorium tremulum (Asteraceae) em bovinos. Pesquisa Veterinária Brasi-leira 27(10):442-445. Departamento de Clínica e Patologia, Centro de Ciências Agroveterinárias, Univer-sidade do Estado de Santa Catarina, Lages, SC 88520-000, Brazil. E-mail: a2ag@cav.udesc.br The spontaneous and experimental poisoning by Eupatorium tremulum in cattle is described. Spontaneous cases were diagnosed in a herd of 19 cattle in the municipality of Lages, Santa Catarina, Brazil. Three of the animals were found dead after having been transferred to a pasture with abundant quantities of E. tremulum. On two of them postmortem examination was performed and several internal organs were sampled for histological examination. Green leaves of E. tremulum were force-fed orally to 5 calves in single doses of 23-32g/kg body weight. Three calves showed clinical signs and two died. The main clinical signs included anorexia, apathy, absence of rumen movements, diarrhea and a flabby abdominal wall. Gross changes were restricted to the fore stomachs and were identical to those observed in the cases of natural poisoning. Rumen and reticulum were slightly reddish from outside; the corneal layer of their internal lining was loosely attached to a markedly red mucosa. The histological examination of rumen and reticulum from spontaneous and experimental cases revealed necrosis and vesicle formation in the epithelium; in some segments of the ruminal mucosa there was detachment of the epithelial covering and infiltration by neuthophils. Poisoning by E. tremulum has clinical course, gross lesions and histopathology very similar to those observed in poisoning caused by ingestion of the plants Baccharidastrum triplinervium, Baccharis coridifolia and Baccharis megapotamica var. weirii. The diagnosis of the spontaneous cases here described was confirmed by epidemiological data and the experimental reproduction of characteristic gross lesions and histopathology.

• Poisonous plants plant poisoning Eupatorium tremulum Asteraceae diseases of cattle digestive tract

Abstract in Portuguese:

ABSTRACT.- Lucioli J., Furlan F.H., Mezaroba S., Traverso S. D. & Gava A. 2007. [Spontaneous and experimental poisoning by Eupatorium tremulum (Asteraceae) in cattle.] Intoxicação espon-tânea e experimental por Eupatorium tremulum (Asteraceae) em bovinos. Pesquisa Veterinária Brasi-leira 27(10):442-445. Departamento de Clínica e Patologia, Centro de Ciências Agroveterinárias, Univer-sidade do Estado de Santa Catarina, Lages, SC 88520-000, Brazil. E-mail: a2ag@cav.udesc.br The spontaneous and experimental poisoning by Eupatorium tremulum in cattle is described. Spontaneous cases were diagnosed in a herd of 19 cattle in the municipality of Lages, Santa Catarina, Brazil. Three of the animals were found dead after having been transferred to a pasture with abundant quantities of E. tremulum. On two of them postmortem examination was performed and several internal organs were sampled for histological examination. Green leaves of E. tremulum were force-fed orally to 5 calves in single doses of 23-32g/kg body weight. Three calves showed clinical signs and two died. The main clinical signs included anorexia, apathy, absence of rumen movements, diarrhea and a flabby abdominal wall. Gross changes were restricted to the fore stomachs and were identical to those observed in the cases of natural poisoning. Rumen and reticulum were slightly reddish from outside; the corneal layer of their internal lining was loosely attached to a markedly red mucosa. The histological examination of rumen and reticulum from spontaneous and experimental cases revealed necrosis and vesicle formation in the epithelium; in some segments of the ruminal mucosa there was detachment of the epithelial covering and infiltration by neuthophils. Poisoning by E. tremulum has clinical course, gross lesions and histopathology very similar to those observed in poisoning caused by ingestion of the plants Baccharidastrum triplinervium, Baccharis coridifolia and Baccharis megapotamica var. weirii. The diagnosis of the spontaneous cases here described was confirmed by epidemiological data and the experimental reproduction of characteristic gross lesions and histopathology.

Abstract in English:

ABSTRACT.- Schons S.V., Kommers G.D., Pereira G.M., Raffi M.B. & Schild A.L. 2007. [Microscopic, immunohistochemical, and ultra-structural study of the lesions experimentaly induced by Ramaria flavo-brunnescens (Clavariaceae) in cattle.] Estudo histológico, imuno-histoquímico e ultra-estrutural das lesões induzidas experimentalmente por Ramaria flavo-brunnescens (Clavariaceae) em bovinos. Pesquisa Veterinária Brasileira 27(7):269-276. Laboratório Regional de Diagnóstico, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br The objective of this study was to investigate the pathogenesis of the lesions observed in cattle experimentally poisoned by Ramaria flavo-brunnescens. The mushroom was given to three 9 to10-month-old Jersey calves immediately after harvesting. Daily doses were around 20g/kg of body weight during 7 (Calf 1) or 13 days (Calves 2-3), and the total doses of mushroom given were 140, 268, and 261g/kg of body weight, respectively. One calf (Calf 4) with same age and breed was used as control. Clinical signs were characterized by prostration, anorexia, hyperemia of oral mucosa, and loosening of long hairs of the tail tip under mild traction. The calves were submitted to euthanasia and necropsied on days 8 (Calf 1) and 15 (Calves 2-4) after the beginning of the experiment. Microscopically, there was smoothness of dorsal epithelium of tongue with absence of filiform papillae, vacuolation of keratinocytes, and loosening of the keratin layer. In the hooves, there was vacuolation and irregular keratinization of the laminar epidermis and hyperplasia of keratinocytes. Hyperkeratosis, vacuolation of the external root sheath, thickening of tricholemal keratin, and inflammatory infiltration around hair follicles were observed on the skin of the tail tip. Immunohistochemical results with anti-pancytoceratin and anti-Ki67 (cell proliferation marker) antibodies showed no differences between the tongue dorsal epithelium of the control and experimental calves. Ultrastructural study demonstrated decrease in tonofilaments and increased intercellular spaces of the spinous layer of the tongue dorsal epithelium. The results of this study favor the hypothesis of an interference with the epithelial keratinization mechanisms by the toxic principles of Ramaria flavo-brunnescens.

• Ramaria flavo-brunnecens mushroom poisoning cattle diseases pathology

Abstract in Portuguese:

ABSTRACT.- Schons S.V., Kommers G.D., Pereira G.M., Raffi M.B. & Schild A.L. 2007. [Microscopic, immunohistochemical, and ultra-structural study of the lesions experimentaly induced by Ramaria flavo-brunnescens (Clavariaceae) in cattle.] Estudo histológico, imuno-histoquímico e ultra-estrutural das lesões induzidas experimentalmente por Ramaria flavo-brunnescens (Clavariaceae) em bovinos. Pesquisa Veterinária Brasileira 27(7):269-276. Laboratório Regional de Diagnóstico, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br The objective of this study was to investigate the pathogenesis of the lesions observed in cattle experimentally poisoned by Ramaria flavo-brunnescens. The mushroom was given to three 9 to10-month-old Jersey calves immediately after harvesting. Daily doses were around 20g/kg of body weight during 7 (Calf 1) or 13 days (Calves 2-3), and the total doses of mushroom given were 140, 268, and 261g/kg of body weight, respectively. One calf (Calf 4) with same age and breed was used as control. Clinical signs were characterized by prostration, anorexia, hyperemia of oral mucosa, and loosening of long hairs of the tail tip under mild traction. The calves were submitted to euthanasia and necropsied on days 8 (Calf 1) and 15 (Calves 2-4) after the beginning of the experiment. Microscopically, there was smoothness of dorsal epithelium of tongue with absence of filiform papillae, vacuolation of keratinocytes, and loosening of the keratin layer. In the hooves, there was vacuolation and irregular keratinization of the laminar epidermis and hyperplasia of keratinocytes. Hyperkeratosis, vacuolation of the external root sheath, thickening of tricholemal keratin, and inflammatory infiltration around hair follicles were observed on the skin of the tail tip. Immunohistochemical results with anti-pancytoceratin and anti-Ki67 (cell proliferation marker) antibodies showed no differences between the tongue dorsal epithelium of the control and experimental calves. Ultrastructural study demonstrated decrease in tonofilaments and increased intercellular spaces of the spinous layer of the tongue dorsal epithelium. The results of this study favor the hypothesis of an interference with the epithelial keratinization mechanisms by the toxic principles of Ramaria flavo-brunnescens.

Abstract in English:

ABSTRACT.- Oliveira K.D., França T.N., Nogueira V.A. & Peixoto P.V. 2006. [Diseases associated with selenium poisoning in animals.] Enfermidades associadas à intoxicação por selênio em animais. Pesquisa Veterinária Brasileira 27(4):125-136. Departamento de Nutrição Animal e Pastagem, Instituto de Zootecnia, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: krishna.oliveira@uvv.br Trough a critical literature review, the main data of selenium poisoning in domestic animals are presented. Epidemiological, clinical, anatomic and histopathological aspects attributed to Alkali Disease, Blind Staggers, acute poisoning and focal symmetrical poliomielomalacia of swine are discussed. The main objective of the paper is to clarify obscure points of selenium poisoning, as well to point out the risks that supplementation with this element can represent.

• Selenium poisoning alkali disease blind staggers focal symmetrical poliomielomalacia

Abstract in Portuguese:

ABSTRACT.- Oliveira K.D., França T.N., Nogueira V.A. & Peixoto P.V. 2006. [Diseases associated with selenium poisoning in animals.] Enfermidades associadas à intoxicação por selênio em animais. Pesquisa Veterinária Brasileira 27(4):125-136. Departamento de Nutrição Animal e Pastagem, Instituto de Zootecnia, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: krishna.oliveira@uvv.br Trough a critical literature review, the main data of selenium poisoning in domestic animals are presented. Epidemiological, clinical, anatomic and histopathological aspects attributed to Alkali Disease, Blind Staggers, acute poisoning and focal symmetrical poliomielomalacia of swine are discussed. The main objective of the paper is to clarify obscure points of selenium poisoning, as well to point out the risks that supplementation with this element can represent.

Abstract in English:

ABSTRACT.- Lucioli J., Furlan F.H., Mezaroba S., Bechtold S.L., Gava A. & Traverso S.D. 2007. [Acute sodium fluorsilicate poisoning in cattle in the state of Santa Catarina.] Intoxicação aguda por fluorsilicato de sódio em bovinos no Estado de Santa Catarina. Pesquisa Veterinária Brasileira 27(1):49-52. Laboratório de Patologia Animal, Departamento de Clínica e Patologia, Faculdade de Veterinária, UDESC, Avenida Luís de Camões 2090, Lages, SC 88520-000, Brazil. E-mail: a2sdt@cav.udesc.br An acute poisoning with sodium fluorsilicate in six cattle is reported, as well as the experimental reproduction by oral administration of the compound to two bovines. Clinical manifestations of the natural poisoning include muscle tremors, hypersalivation, groaning and rapid death. In the experimental poisoning lateral recumbency, dyspnea, tetanic spasms and paddling was also observed. The main necropsy findings were reddening, edema and ulceration of the ruminal and abomasal mucosa. Histopathological findings were necrosis of the epithelium of the forestomachs with polymorphonuclear infiltration of the submucosal and muscular layers. Tubular renal necrosis, liver portal necrosis and necrosis of the lymphoid tissues was also noted. The sodium fluorsilicate caused clinical signs at a dose of 300mg/kg, and death from 400mg/kg on.

• Sodium fluorsilicate poisoning cattle pathology

Abstract in Portuguese:

ABSTRACT.- Lucioli J., Furlan F.H., Mezaroba S., Bechtold S.L., Gava A. & Traverso S.D. 2007. [Acute sodium fluorsilicate poisoning in cattle in the state of Santa Catarina.] Intoxicação aguda por fluorsilicato de sódio em bovinos no Estado de Santa Catarina. Pesquisa Veterinária Brasileira 27(1):49-52. Laboratório de Patologia Animal, Departamento de Clínica e Patologia, Faculdade de Veterinária, UDESC, Avenida Luís de Camões 2090, Lages, SC 88520-000, Brazil. E-mail: a2sdt@cav.udesc.br An acute poisoning with sodium fluorsilicate in six cattle is reported, as well as the experimental reproduction by oral administration of the compound to two bovines. Clinical manifestations of the natural poisoning include muscle tremors, hypersalivation, groaning and rapid death. In the experimental poisoning lateral recumbency, dyspnea, tetanic spasms and paddling was also observed. The main necropsy findings were reddening, edema and ulceration of the ruminal and abomasal mucosa. Histopathological findings were necrosis of the epithelium of the forestomachs with polymorphonuclear infiltration of the submucosal and muscular layers. Tubular renal necrosis, liver portal necrosis and necrosis of the lymphoid tissues was also noted. The sodium fluorsilicate caused clinical signs at a dose of 300mg/kg, and death from 400mg/kg on.

Abstract in English:

ABSTRACT.- Nóbrega Jr J.E., Riet-Correa F., Medeiros R.M.T. & Dantas A.F.M. 2006. [Poisoning by Sorghum halepense (Poaceae) in cattle in the Brazilian semiarid.] Intoxicação por Sorghum halepense em bovinos no semi-árido. Pesquisa Veterinária Brasileira 26(4):201-204. Hospital Veterinário, CSTR, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, PB, Brazil. E-mail: franklin.riet@pesquisador.com.br An outbreak of poisoning by Sorghum halepense (L.) Pers. in cattle in the Brazilian semiarid is reported. Nine cattle were introduced 15 days after the first rains into a paddock where the plant was sprouting and had 25-30cm high. Clinical signs of dyspnea, anxiety, muscular tremors and incoordination appeared 15 minutes after the animals began to graze. Two of them died within about 3 hours. The others recovered. Cyanotic mucosa, dark muscles, lung edema and hemorrhages, and leaves of the plant in the rumen were observed at necropsy. The plant was positive for the picrosodic paper test. S. halepense from another farm of occurrence of the poisoning was transplanted into two pots. The picrosodic paper test was performed fortnightly in the plants growing in one of them. The plant was positive for cyanide in all growth stages; during the first 45 days the test was positive within 1 minute, but after day 60 within 3 minutes. Thirty days after the plant had been transplanted into one of the pots, it was administered to a goat at a dose of 11.8g/kg, causing clinical signs of HCN poisoning. The animal recovered after the intravenous administration of 5mL/10kg body weight of a 20% sodium thiosulfate solution. In the Brazilian semiarid S. halepense is frequently found invading the border of ponds and irrigated crops, and is used as forage during the dry season.

• Poisonous plants Sorghum halepense cyanogenic glycosides plant poisoning cattle

Abstract in Portuguese:

ABSTRACT.- Nóbrega Jr J.E., Riet-Correa F., Medeiros R.M.T. & Dantas A.F.M. 2006. [Poisoning by Sorghum halepense (Poaceae) in cattle in the Brazilian semiarid.] Intoxicação por Sorghum halepense em bovinos no semi-árido. Pesquisa Veterinária Brasileira 26(4):201-204. Hospital Veterinário, CSTR, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, PB, Brazil. E-mail: franklin.riet@pesquisador.com.br An outbreak of poisoning by Sorghum halepense (L.) Pers. in cattle in the Brazilian semiarid is reported. Nine cattle were introduced 15 days after the first rains into a paddock where the plant was sprouting and had 25-30cm high. Clinical signs of dyspnea, anxiety, muscular tremors and incoordination appeared 15 minutes after the animals began to graze. Two of them died within about 3 hours. The others recovered. Cyanotic mucosa, dark muscles, lung edema and hemorrhages, and leaves of the plant in the rumen were observed at necropsy. The plant was positive for the picrosodic paper test. S. halepense from another farm of occurrence of the poisoning was transplanted into two pots. The picrosodic paper test was performed fortnightly in the plants growing in one of them. The plant was positive for cyanide in all growth stages; during the first 45 days the test was positive within 1 minute, but after day 60 within 3 minutes. Thirty days after the plant had been transplanted into one of the pots, it was administered to a goat at a dose of 11.8g/kg, causing clinical signs of HCN poisoning. The animal recovered after the intravenous administration of 5mL/10kg body weight of a 20% sodium thiosulfate solution. In the Brazilian semiarid S. halepense is frequently found invading the border of ponds and irrigated crops, and is used as forage during the dry season.

Abstract in English:

ABSTRACT.- Carvalho N.M., Alonso L.A., Cunha T.G., Ravedutti J., Barros C.S.L. & Lemos R.A.A. 2006. [Poisoning of cattle by Tetrapterys multiglandulosa in Mato Grosso do Sul, Brazil.] Intoxicação de bovinos por Tetrapterys multiglandulosa (Malpighiaceae) em Mato Grosso do Sul. Pesquisa Veterinária Brasileira 26(3):139-146. Departamento de Medicina Veterinária, Universidade Federal de Mato Grosso do Sul, Avenida Senador Filinto Müller 2443, Caixa Postal 549, Campo Grande, MS 79070-900, Brazil. E-mail: eqrural@nin.ufms.br Two outbreaks of poisoning by Tetrapterys multiglandulosa in cattle and the experimental reproduction of the toxicosis in sheep are described. Both outbreaks occurred on the same farm in the municipality of Bataiporã, state of Mato Grosso do Sul, Brazil. The first outbreak occurred in July-October 2004 and involved a cattle population at risk of 290 pregnant cows, which were introduced into a 60 hectare pasture with a legal reservation area heavily infested by T. multiglandulosa. Of these, 230 cows (79.3%) aborted, had stillbirths or delivered weak calves that died few days after birth. Seven cows died, and one cow and a 10-day-old calf were necropsied. The second outbreak occurred in September-October 2005, 40 days after 285 2-year-old heifers were introduced into the same pasture infested by T. multiglandulosa and where the first outbreak had occurred in the previous year. Nine heifers got sick and died, and three of then were necropsied. Clinical signs of affected cattle, including a 10-day-old calf, were marked lethargy, loss of weight with distension of the abdomen (ascites), subcutaneous dependant edema, distended and pulsating jugular veins, dyspnea and cardiac arrhythmia. Necropsy findings included a round and dilated heart with whitish and firm areas in the myocardium, and changes related to cardiac failure such as cavitary edema, nutmeg liver, pulmonary edema, a large blood clot in the left ventricle. Histopathological changes included necrosis and fibrosis in the myocardium, chronic passive hepatic centrolobular congestion, pulmonary edema, and spongy degeneration in the white matter of the brain. Experimental sheep died 29 (Sheep 1) and 35 (Sheep 2) days after being fed average daily doses of T. multiglandulosa corresponding to 14g/kg (Sheep 1) and 7,5 g/kg (Sheep 2) per day. Clinical signs were observed from the 7th day (Sheep1) and the 4th day (Sheep 2) of the experiment and included tachycardia, arrhythmia, lethargy and head pressing. Necropsy and histopathologic findings in both experimental sheep were very similar to those observed in affected cattle of the two spontaneous outbreaks.

• Poisonous plants Tetrapterys multiglandulosa Malpighiaceae plant poisoning cardiomiopathy abortion diseases of cattle pathology

Abstract in Portuguese:

ABSTRACT.- Carvalho N.M., Alonso L.A., Cunha T.G., Ravedutti J., Barros C.S.L. & Lemos R.A.A. 2006. [Poisoning of cattle by Tetrapterys multiglandulosa in Mato Grosso do Sul, Brazil.] Intoxicação de bovinos por Tetrapterys multiglandulosa (Malpighiaceae) em Mato Grosso do Sul. Pesquisa Veterinária Brasileira 26(3):139-146. Departamento de Medicina Veterinária, Universidade Federal de Mato Grosso do Sul, Avenida Senador Filinto Müller 2443, Caixa Postal 549, Campo Grande, MS 79070-900, Brazil. E-mail: eqrural@nin.ufms.br Two outbreaks of poisoning by Tetrapterys multiglandulosa in cattle and the experimental reproduction of the toxicosis in sheep are described. Both outbreaks occurred on the same farm in the municipality of Bataiporã, state of Mato Grosso do Sul, Brazil. The first outbreak occurred in July-October 2004 and involved a cattle population at risk of 290 pregnant cows, which were introduced into a 60 hectare pasture with a legal reservation area heavily infested by T. multiglandulosa. Of these, 230 cows (79.3%) aborted, had stillbirths or delivered weak calves that died few days after birth. Seven cows died, and one cow and a 10-day-old calf were necropsied. The second outbreak occurred in September-October 2005, 40 days after 285 2-year-old heifers were introduced into the same pasture infested by T. multiglandulosa and where the first outbreak had occurred in the previous year. Nine heifers got sick and died, and three of then were necropsied. Clinical signs of affected cattle, including a 10-day-old calf, were marked lethargy, loss of weight with distension of the abdomen (ascites), subcutaneous dependant edema, distended and pulsating jugular veins, dyspnea and cardiac arrhythmia. Necropsy findings included a round and dilated heart with whitish and firm areas in the myocardium, and changes related to cardiac failure such as cavitary edema, nutmeg liver, pulmonary edema, a large blood clot in the left ventricle. Histopathological changes included necrosis and fibrosis in the myocardium, chronic passive hepatic centrolobular congestion, pulmonary edema, and spongy degeneration in the white matter of the brain. Experimental sheep died 29 (Sheep 1) and 35 (Sheep 2) days after being fed average daily doses of T. multiglandulosa corresponding to 14g/kg (Sheep 1) and 7,5 g/kg (Sheep 2) per day. Clinical signs were observed from the 7th day (Sheep1) and the 4th day (Sheep 2) of the experiment and included tachycardia, arrhythmia, lethargy and head pressing. Necropsy and histopathologic findings in both experimental sheep were very similar to those observed in affected cattle of the two spontaneous outbreaks.

Abstract in English:

ABSTRACT.- Barbosa J.D., Oliveira C.M.C., Tokarnia C.H. & Peixoto P.V. 2006. [Hepatogenous photosensitization in horses caused by Brachiaria humidicola (Gramineae) in the State of Pará.] Fotossensibilização hepatógena em eqüinos pela ingestão de Brachiaria humidicola (Gramineae) no Estado do Pará. Pesquisa Veterinária Brasileira 26(3):147-153. Escola de Medicina Veterinária, Campus Castanhal, Universidade Federal do Pará, Rua Maximino Porpino 1000, Castanhal, PA 68743-080, Brazil. E-mail: diomedes@ufpa.br Data on the clinical-pathological aspects and on the epidemioloy of a disease in horses, characterized by phototsensitization, which occurs in northeastern of Pará, Brazil, are presented. Of a total of 40 horses examined clinically, post-mortem examination was performed on seven. Due to the characteristic lesions found on the non-pigmented skin, the macroscopic and histological alterations in the liver, and knowing that Brachiaria grasses contain saponins with toxic properties, which cause liver lesions and photosensitization in cattle and sheep, it is concluded that this disease in horses is caused by grassing exclusively Brachiaria humidicola.

• Poisonous plants Brachiaria humidicola plant poisoning photosensitization saponins horses

Abstract in Portuguese:

ABSTRACT.- Barbosa J.D., Oliveira C.M.C., Tokarnia C.H. & Peixoto P.V. 2006. [Hepatogenous photosensitization in horses caused by Brachiaria humidicola (Gramineae) in the State of Pará.] Fotossensibilização hepatógena em eqüinos pela ingestão de Brachiaria humidicola (Gramineae) no Estado do Pará. Pesquisa Veterinária Brasileira 26(3):147-153. Escola de Medicina Veterinária, Campus Castanhal, Universidade Federal do Pará, Rua Maximino Porpino 1000, Castanhal, PA 68743-080, Brazil. E-mail: diomedes@ufpa.br Data on the clinical-pathological aspects and on the epidemioloy of a disease in horses, characterized by phototsensitization, which occurs in northeastern of Pará, Brazil, are presented. Of a total of 40 horses examined clinically, post-mortem examination was performed on seven. Due to the characteristic lesions found on the non-pigmented skin, the macroscopic and histological alterations in the liver, and knowing that Brachiaria grasses contain saponins with toxic properties, which cause liver lesions and photosensitization in cattle and sheep, it is concluded that this disease in horses is caused by grassing exclusively Brachiaria humidicola.

Abstract in English:

ABSTRACT.- Seixas J.N., Peixoto P.V., Armién A.G., Jabour F.F. & Brito M.F. 2006. [Clinical and pathogenetic aspects of abamectin poisoning in calves.] Aspectos clínicos e patogenéticos da intoxicação por abamectina em bezerros. Pesquisa Veterinária Brasileira 26(3):161-166. Pro-jeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23890-000, Brazil. E-mail: josiseixas@ufrrj.br Clinic-pathological aspects and the pathogenesis of experimental abamectin poisoning were studied, after subcutaneous administration of different abamectin doses in 9 calves, as well as the clini-cal and pathological aspects of 74 cases of the iatrogenic poisoning with this drug in cattle, which occurred in the states of Rio Grande do Sul, Pará, Maranhão, Paraíba and Mato Grosso do Sul. From the 9 calves submitted to experimental administration of single doses, 5 calves died (4 calves received doses 6-10 times higher than recommended, and one received the therapeutic daily dose during 11 days). Abamectin poisoning induces neurological dysfunctions, characterized by an initial phase of hyperexcitability, followed by widespread muscular hypotony and progressive depression. No macroscopic or microscopic alterations were observed in the central nervous system or in any other organ. It is concluded that abamectin is an antihelmintic which should be used with restriction, because of the risks leading to death when used in young calves, even in therapeutic doses.

• Abamectin poisoning neurological alterations calves

Abstract in Portuguese:

ABSTRACT.- Seixas J.N., Peixoto P.V., Armién A.G., Jabour F.F. & Brito M.F. 2006. [Clinical and pathogenetic aspects of abamectin poisoning in calves.] Aspectos clínicos e patogenéticos da intoxicação por abamectina em bezerros. Pesquisa Veterinária Brasileira 26(3):161-166. Pro-jeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23890-000, Brazil. E-mail: josiseixas@ufrrj.br Clinic-pathological aspects and the pathogenesis of experimental abamectin poisoning were studied, after subcutaneous administration of different abamectin doses in 9 calves, as well as the clini-cal and pathological aspects of 74 cases of the iatrogenic poisoning with this drug in cattle, which occurred in the states of Rio Grande do Sul, Pará, Maranhão, Paraíba and Mato Grosso do Sul. From the 9 calves submitted to experimental administration of single doses, 5 calves died (4 calves received doses 6-10 times higher than recommended, and one received the therapeutic daily dose during 11 days). Abamectin poisoning induces neurological dysfunctions, characterized by an initial phase of hyperexcitability, followed by widespread muscular hypotony and progressive depression. No macroscopic or microscopic alterations were observed in the central nervous system or in any other organ. It is concluded that abamectin is an antihelmintic which should be used with restriction, because of the risks leading to death when used in young calves, even in therapeutic doses.

Abstract in English:

ABSTRACT.- Jabour F.F., Seixas J.N., Tokarnia C.H. & Brito M.F. 2006. [Variation of the toxicity of Arrabidaea bilabiata (Bignoniaceae) in rabbits.] Variação da toxidez de Arrabidaea bilabiata (Bignoniaceae) em coelhos. Pesquisa Veterinária Brasileira 26(3):171-176. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23.890-000, Brazil. E-mail: flaviajabour@bol.com.br The dried and powdered mature leaves and sprouts of Arrabidaea bilabiata (fam. Bignoniaceae), a liana or scandent shrub, were administered by stomach tube to 15 rabbits at doses of 0.25-6.0g/kg. The lowest dose of the sprouts collected in October (End of the dry season) causing death was 0.5g/kg, whilst the lowest lethal dose of sprouts collected in May (End of the rainy season) was 1.0g/kg. With the mature leaves collected in October the lowest lethal dose was of 4.0g/kg, and the lowest lethal dose of the mature leaves collected in May was 6.0g/kg. The clinical course of the poisoning was peracute. The rabbits all of a sudden fell down with struggling movements, difficult and spaced breathing, and died. At necropsy, significant alterations were not observed and histopatological examination showed, as the more important changes, vacuolar hydropic degeneration of epithelial cells of the distal convoluted renal tubules, diffuse vacuolation of the cytoplasm and necrosis of hepatocytes, presence of eosinophilic sphaerules in the sinusoids, groups of heart muscle fibers with increased eosinophilia, besides congestion in the kidneys, liver, heart and lungs. It was concluded that the toxicity of A. bilabiata varies according to the season of the year and the growth stage of the plant. The plant was most toxic in October and the sprouts were more toxic than the mature leaves, confirming the data previously obtained in experiments with cattle and buffalos.

• Poisonous plants Arrabidaea bilabiata Bignoniaceae plant poisoning rabbit pathology

Abstract in Portuguese:

ABSTRACT.- Jabour F.F., Seixas J.N., Tokarnia C.H. & Brito M.F. 2006. [Variation of the toxicity of Arrabidaea bilabiata (Bignoniaceae) in rabbits.] Variação da toxidez de Arrabidaea bilabiata (Bignoniaceae) em coelhos. Pesquisa Veterinária Brasileira 26(3):171-176. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23.890-000, Brazil. E-mail: flaviajabour@bol.com.br The dried and powdered mature leaves and sprouts of Arrabidaea bilabiata (fam. Bignoniaceae), a liana or scandent shrub, were administered by stomach tube to 15 rabbits at doses of 0.25-6.0g/kg. The lowest dose of the sprouts collected in October (End of the dry season) causing death was 0.5g/kg, whilst the lowest lethal dose of sprouts collected in May (End of the rainy season) was 1.0g/kg. With the mature leaves collected in October the lowest lethal dose was of 4.0g/kg, and the lowest lethal dose of the mature leaves collected in May was 6.0g/kg. The clinical course of the poisoning was peracute. The rabbits all of a sudden fell down with struggling movements, difficult and spaced breathing, and died. At necropsy, significant alterations were not observed and histopatological examination showed, as the more important changes, vacuolar hydropic degeneration of epithelial cells of the distal convoluted renal tubules, diffuse vacuolation of the cytoplasm and necrosis of hepatocytes, presence of eosinophilic sphaerules in the sinusoids, groups of heart muscle fibers with increased eosinophilia, besides congestion in the kidneys, liver, heart and lungs. It was concluded that the toxicity of A. bilabiata varies according to the season of the year and the growth stage of the plant. The plant was most toxic in October and the sprouts were more toxic than the mature leaves, confirming the data previously obtained in experiments with cattle and buffalos.