PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

Lima E.F., Riet-Correa F., Castro R.S., Gomes A.A.B. & Lima F.S. 2005. [Clinical signs, distribution of the lesions in the central nervous system and epidemiology of rabies in northeastern Brazil.] Sinais clínicos, distribuição das lesões no sistema nervoso e epidemiologia da raiva em herbívoros na região Nordeste do Brasil. Pesquisa Veterinária Brasileira 25(4):250-264. Centro de Saúde e Tecnologia Rural, Campus de Patos, Universidade Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: riet@cstr.ufcg.br Twenty four outbreaks of rabies in cattle, 4 in horses, 2 in sheep, and 2 in goats are reported in northeastern Brazil. All outbreaks occurred in the state of Paraíba, except one in horses that occurred in the state of Rio Grande do Norte. All outbreaks, except one in sheep, were probably transmitted by vampire-bats, but the transmission by foxes (Dusicyon vetulus) is also possible. Clinical signs were characteristic for distribution of the lesions in the central nervous system (CNS). In cattle, signs were mainly of the paralytic form of rabies, caused by lesions on the spinal cord, brain stem and cerebellum; but some animals showed also depression, excitation and other signs due to cerebral lesions. In 3 out of 5 horses, the main clinical signs were due to lesions in the cerebrum, and 2 had the paralytic form. From 4 sheep and 2 goats affected, 4 showed clinical signs of the paralytic form; but in 1 goat and 1 sheep the main clinical signs were caused by cerebral lesions. All affected animals, except 1 goat, had a clinical manifestation period of 2-8 days. The only gross lesions were distention of the urinary bladder in 4 cattle and distention of the rectum in 2 others. Two horses had skin lesions due to traumatic injury. Histologic lesions were diffuse non-suppurative encephalomyelitis and meningitis. In the horses, and in one goat with a clinical manifestation period of 35 days, the lesions were more severe, with neuronal necrosis, neuronophagia, and presence of axonal spheroids. Negri bodies were found in 87% (20/23) of the cattle cases examined histologically. In small ruminants Negri bodies were found in 83% (5/6) of the cases. In sheep, goats and cattle, Negri bodies were more frequent in the cerebellum, but they were found also in brain stem, spinal cord and cerebrum. In horses, Negri bodies were found in small amounts only in the cortex of one animal, and in the cortex and hippocampus of another. Histologic lesions and Negri bodies in the trigeminal ganglia were less frequent than in the CNS. These results show that in rabies of herbivores, clinical signs and distribution of lesions in the CNS are variable, so that for the diagnosis and adequate clinical evaluation and the histologic study of different areas of the CNS are necessary. This also suggests that when the fluorescent antibody test and mouse inoculation test are negative, they should be repeated with samples from different areas of the brain and spinal cord. Frequency data of diseases from 4 diagnostic laboratories were used to estimate cattle deaths due to rabies in 3 Brazilian states. In Paraíba, with a population of 918,262 cattle, the annual death rate is estimated in 8,609 heads. In Mato Grosso do Sul, with a population of 23 millions cattle, deaths caused by rabies are estimated in 149,500 heads, and in Rio Grande do Sul, with a cattle population of 13 millions, cattle deaths due to rabies are estimated in 13,000 to 16,250 heads. If these data are used to estimate cattle losses in Brazil, with a cattle population of 195 millions, it can be estimated that 842,688 deaths are caused annually by rabies.

• Rabies cattle sheep goats horses pathology clinical signs economical impact.

Abstract in Portuguese:

Lima E.F., Riet-Correa F., Castro R.S., Gomes A.A.B. & Lima F.S. 2005. [Clinical signs, distribution of the lesions in the central nervous system and epidemiology of rabies in northeastern Brazil.] Sinais clínicos, distribuição das lesões no sistema nervoso e epidemiologia da raiva em herbívoros na região Nordeste do Brasil. Pesquisa Veterinária Brasileira 25(4):250-264. Centro de Saúde e Tecnologia Rural, Campus de Patos, Universidade Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: riet@cstr.ufcg.br Twenty four outbreaks of rabies in cattle, 4 in horses, 2 in sheep, and 2 in goats are reported in northeastern Brazil. All outbreaks occurred in the state of Paraíba, except one in horses that occurred in the state of Rio Grande do Norte. All outbreaks, except one in sheep, were probably transmitted by vampire-bats, but the transmission by foxes (Dusicyon vetulus) is also possible. Clinical signs were characteristic for distribution of the lesions in the central nervous system (CNS). In cattle, signs were mainly of the paralytic form of rabies, caused by lesions on the spinal cord, brain stem and cerebellum; but some animals showed also depression, excitation and other signs due to cerebral lesions. In 3 out of 5 horses, the main clinical signs were due to lesions in the cerebrum, and 2 had the paralytic form. From 4 sheep and 2 goats affected, 4 showed clinical signs of the paralytic form; but in 1 goat and 1 sheep the main clinical signs were caused by cerebral lesions. All affected animals, except 1 goat, had a clinical manifestation period of 2-8 days. The only gross lesions were distention of the urinary bladder in 4 cattle and distention of the rectum in 2 others. Two horses had skin lesions due to traumatic injury. Histologic lesions were diffuse non-suppurative encephalomyelitis and meningitis. In the horses, and in one goat with a clinical manifestation period of 35 days, the lesions were more severe, with neuronal necrosis, neuronophagia, and presence of axonal spheroids. Negri bodies were found in 87% (20/23) of the cattle cases examined histologically. In small ruminants Negri bodies were found in 83% (5/6) of the cases. In sheep, goats and cattle, Negri bodies were more frequent in the cerebellum, but they were found also in brain stem, spinal cord and cerebrum. In horses, Negri bodies were found in small amounts only in the cortex of one animal, and in the cortex and hippocampus of another. Histologic lesions and Negri bodies in the trigeminal ganglia were less frequent than in the CNS. These results show that in rabies of herbivores, clinical signs and distribution of lesions in the CNS are variable, so that for the diagnosis and adequate clinical evaluation and the histologic study of different areas of the CNS are necessary. This also suggests that when the fluorescent antibody test and mouse inoculation test are negative, they should be repeated with samples from different areas of the brain and spinal cord. Frequency data of diseases from 4 diagnostic laboratories were used to estimate cattle deaths due to rabies in 3 Brazilian states. In Paraíba, with a population of 918,262 cattle, the annual death rate is estimated in 8,609 heads. In Mato Grosso do Sul, with a population of 23 millions cattle, deaths caused by rabies are estimated in 149,500 heads, and in Rio Grande do Sul, with a cattle population of 13 millions, cattle deaths due to rabies are estimated in 13,000 to 16,250 heads. If these data are used to estimate cattle losses in Brazil, with a cattle population of 195 millions, it can be estimated that 842,688 deaths are caused annually by rabies.

Abstract in English:

Zafalon L.F., Nader Filho A., Oliveira J.V. & Resende F.D. 2005. [Electrical conductivity and chloride concentration of milk as auxiliary diagnostic methods in bovine subclinical mastitis.] Comportamento da condutividade elétrica e do conteúdo de cloretos do leite como métodos auxiliares de diagnóstico na mastite subclínica bovina. Pesquisa Veterinária Brasileira 25(3):159-163. Depto Medicina Veterinária Preventiva e Reprodução Animal, FACVJ, Unesp - Campus de Jaboticabal, Via de Acesso Prof. Paulo Donato Castellane s/no, Jaboticabal, SP 14884-900, Brazil. E-mail: zafalon@iz.sp.gov.br Electrical conductivity measured by a hand-held meter and chloride concentration of milk were studied as auxiliary methods for diagnosis of bovine subclinical mastitis in the identification of affected mammary quarters where Staphylococcus aureus and Corynebacterium sp were later isolated. Tests were made during 2 years in Holstein cows of a dairy farm producing type C milk, where milking was performed once a day. Sensitivities of electrical conductivity and chloride concentration tests from mammary quarters, where Corynebacterium sp was isolated (65.3% and 78.3%, respectively), were superior to the found in mammary quarters where S. aureus was identified (55.4% and 68.2%, respectively). The efficacies of the two diagnostic tests were similar. Statistical significance was demonstrated with regression analysis of both tests of healthy mammary quarters and subclinical mastitis quarters infected with Staphylococcus aureus.

• Bovine subclinical mastitis electric conductivity chloride level Staphylococcus aureus Corynebacterium sp.

Abstract in Portuguese:

Zafalon L.F., Nader Filho A., Oliveira J.V. & Resende F.D. 2005. [Electrical conductivity and chloride concentration of milk as auxiliary diagnostic methods in bovine subclinical mastitis.] Comportamento da condutividade elétrica e do conteúdo de cloretos do leite como métodos auxiliares de diagnóstico na mastite subclínica bovina. Pesquisa Veterinária Brasileira 25(3):159-163. Depto Medicina Veterinária Preventiva e Reprodução Animal, FACVJ, Unesp - Campus de Jaboticabal, Via de Acesso Prof. Paulo Donato Castellane s/no, Jaboticabal, SP 14884-900, Brazil. E-mail: zafalon@iz.sp.gov.br Electrical conductivity measured by a hand-held meter and chloride concentration of milk were studied as auxiliary methods for diagnosis of bovine subclinical mastitis in the identification of affected mammary quarters where Staphylococcus aureus and Corynebacterium sp were later isolated. Tests were made during 2 years in Holstein cows of a dairy farm producing type C milk, where milking was performed once a day. Sensitivities of electrical conductivity and chloride concentration tests from mammary quarters, where Corynebacterium sp was isolated (65.3% and 78.3%, respectively), were superior to the found in mammary quarters where S. aureus was identified (55.4% and 68.2%, respectively). The efficacies of the two diagnostic tests were similar. Statistical significance was demonstrated with regression analysis of both tests of healthy mammary quarters and subclinical mastitis quarters infected with Staphylococcus aureus.

Abstract in English:

Rissi D.R., Rech R.R., Fighera R.A., Cagnini D.Q., Kommers G.D. & Barros C.S.L. 2005. [Spontaneous Baccharis coridifolia poisoning in cattle.] Intoxicação espontânea por Baccharis coridifolia em bovinos. Pesquisa Veterinária Brasileira 25(2):111-114. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Two outbreaks of Baccharis coridifolia poisoning in cattle in southern Brazil are described. Cases occurred when stressed, hungry and thirsty cattle brought from pastures free of B. coridifolia were placed into pastures heavily infested by this poisonous plant. In the two outbreaks morbidity was 21.73% and 22.51% and lethality was virtually 100%. Clinical signs included mild bloat, instability of hind limbs, muscle tremors, dry muzzle, dry feces or diarrhea, polydipsia and restlessness. Consistent necropsy findings included dehydration, large amounts of ruminal fluid, reddening and erosions of the mucosae of the forestomachs. Degeneration and necrosis of the lining epithelium of the forestomachs and of lymphoid tissue were the main histopathological changes encountered.

• Poisonous plants Baccharis coridifolia Asteraceae diseases of cattle pathology.

Abstract in Portuguese:

Rissi D.R., Rech R.R., Fighera R.A., Cagnini D.Q., Kommers G.D. & Barros C.S.L. 2005. [Spontaneous Baccharis coridifolia poisoning in cattle.] Intoxicação espontânea por Baccharis coridifolia em bovinos. Pesquisa Veterinária Brasileira 25(2):111-114. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Two outbreaks of Baccharis coridifolia poisoning in cattle in southern Brazil are described. Cases occurred when stressed, hungry and thirsty cattle brought from pastures free of B. coridifolia were placed into pastures heavily infested by this poisonous plant. In the two outbreaks morbidity was 21.73% and 22.51% and lethality was virtually 100%. Clinical signs included mild bloat, instability of hind limbs, muscle tremors, dry muzzle, dry feces or diarrhea, polydipsia and restlessness. Consistent necropsy findings included dehydration, large amounts of ruminal fluid, reddening and erosions of the mucosae of the forestomachs. Degeneration and necrosis of the lining epithelium of the forestomachs and of lymphoid tissue were the main histopathological changes encountered.

Abstract in English:

França T.N., Ribeiro C.T., Cunha B.M. & Peixoto P.V. 2005. [Porcine Circovirosis: a review.] Circovirose Suína. Pesquisa Veterinária Brasileira 25(2):59-72. Universidade Estácio de Sá, Curso de Medicina Veterinária, Disciplina de Anatomia Patológica, Estrada Boca do Mato 850, Vargem Pequena, RJ 22783-320, Brazil. E-mail: ticianaf@uol.com.br The literature of Porcine Circovirosis, including the main data on epidemiology and clinical, macroscopic and microscopic alterations of the infection of swine by Porcine Circovirus type 2 (PCV-2), is reviewed. There are various forms of infection: the [Porcine] Postweaning Multisystemic Wasting Syndrome (PMWS), Porcine Congenital Tremor, Porcine Dermatitis and Nephropathy Syndrome, and other associated or correlated diseases as the Porcine Reproductive and Respiratory Syndrome, Proliferative Necrotizing Pneumonia, and reproductive disorders. As PMWS already has been reported from southern Brazil and from the state of Rio de Janeiro, the objective of this review is to draw attention to the implications of this virosis for swine production in Brazil and its economical importance.

• Porcine Circovirosis Porcine Circovirus type 2 Porcine Postweaning Multisystemic Wasting Syndrome Porcine Congenital Tremor Porcine Dermatitis and Nephropathy Syndrome Proliferative Necrotizing Pneumonia reproductive disorders of swine.

Abstract in Portuguese:

França T.N., Ribeiro C.T., Cunha B.M. & Peixoto P.V. 2005. [Porcine Circovirosis: a review.] Circovirose Suína. Pesquisa Veterinária Brasileira 25(2):59-72. Universidade Estácio de Sá, Curso de Medicina Veterinária, Disciplina de Anatomia Patológica, Estrada Boca do Mato 850, Vargem Pequena, RJ 22783-320, Brazil. E-mail: ticianaf@uol.com.br The literature of Porcine Circovirosis, including the main data on epidemiology and clinical, macroscopic and microscopic alterations of the infection of swine by Porcine Circovirus type 2 (PCV-2), is reviewed. There are various forms of infection: the [Porcine] Postweaning Multisystemic Wasting Syndrome (PMWS), Porcine Congenital Tremor, Porcine Dermatitis and Nephropathy Syndrome, and other associated or correlated diseases as the Porcine Reproductive and Respiratory Syndrome, Proliferative Necrotizing Pneumonia, and reproductive disorders. As PMWS already has been reported from southern Brazil and from the state of Rio de Janeiro, the objective of this review is to draw attention to the implications of this virosis for swine production in Brazil and its economical importance.

Abstract in English:

França T.N., Peixoto P.V., Brito M.F., Driemeier D., Mores N. & Zanella J. 2005. [Outbreak of Circovirosis (Porcine Postweaning Multisystemic Wasting Syndrome) in the state of Rio de Janeiro, Brazil.] Surto de Circovirose (Síndrome Definhante Multissistêmica de Suínos Desmamados) no estado do Rio de Janeiro. Pesquisa Veterinária Brasileira 25(1):39-53. Universidade Estácio de Sá, Curso de Medicina Veterinária, Disciplina de Anatomia Patológica, Estrada Boca do Mato 850, Vargem Pequena, RJ 22783-320, Brazil. E-mail: ticianaf@uol.com.br The first outbreak of Postweaning Multisystemic Wasting Syndrome (PMWS) in swine, which occurred in southeastern Brazil, in the state of Rio de Janeiro, is described. The disease, which affects mainly weaned about 4 month-old pigs, caused the death of at least 14 animals. The property, where the outbreak occurred, had inadequate sanitary and management conditions. Clinically the disease was characterized by wasting, poor development, cough, tachypnoea, dispnoea, diarrhoea, ataxia, tremors after stimulation, decubitus and convulsions. The course of the disease was acute or subacute. The most important post-mortem findings were enlarged lymphnodes, non-collapsed lungs, with consolidated areas mainly in the cranial lobes. Histological lesions consisted mainly of lymphohistiocytic infiltration with multinucleate giant cells in lymph nodes, spleen, Peyer’s patches, kidney, lung and liver, depletion or lymphoid hyperplasia, as well as lymphohistiocytic interstitial pneumonia and areas of secondary bronchopneumonia. The diagnosis was established through observations of the symptoms and typical lesions, and was confirmed by immunohistochemical examination and PCR. The objective of this study was to characterize the epidemiological, clinical and pathological aspects of the outbreak of PMWS, because of the severe direct or indirect economical losses caused by the disease to the world pig industry.

• Postweaning multisystemic wasting syndrome porcine circovirus type 2 pathology immunohistochemistry PCR.

Abstract in Portuguese:

França T.N., Peixoto P.V., Brito M.F., Driemeier D., Mores N. & Zanella J. 2005. [Outbreak of Circovirosis (Porcine Postweaning Multisystemic Wasting Syndrome) in the state of Rio de Janeiro, Brazil.] Surto de Circovirose (Síndrome Definhante Multissistêmica de Suínos Desmamados) no estado do Rio de Janeiro. Pesquisa Veterinária Brasileira 25(1):39-53. Universidade Estácio de Sá, Curso de Medicina Veterinária, Disciplina de Anatomia Patológica, Estrada Boca do Mato 850, Vargem Pequena, RJ 22783-320, Brazil. E-mail: ticianaf@uol.com.br The first outbreak of Postweaning Multisystemic Wasting Syndrome (PMWS) in swine, which occurred in southeastern Brazil, in the state of Rio de Janeiro, is described. The disease, which affects mainly weaned about 4 month-old pigs, caused the death of at least 14 animals. The property, where the outbreak occurred, had inadequate sanitary and management conditions. Clinically the disease was characterized by wasting, poor development, cough, tachypnoea, dispnoea, diarrhoea, ataxia, tremors after stimulation, decubitus and convulsions. The course of the disease was acute or subacute. The most important post-mortem findings were enlarged lymphnodes, non-collapsed lungs, with consolidated areas mainly in the cranial lobes. Histological lesions consisted mainly of lymphohistiocytic infiltration with multinucleate giant cells in lymph nodes, spleen, Peyer’s patches, kidney, lung and liver, depletion or lymphoid hyperplasia, as well as lymphohistiocytic interstitial pneumonia and areas of secondary bronchopneumonia. The diagnosis was established through observations of the symptoms and typical lesions, and was confirmed by immunohistochemical examination and PCR. The objective of this study was to characterize the epidemiological, clinical and pathological aspects of the outbreak of PMWS, because of the severe direct or indirect economical losses caused by the disease to the world pig industry.

Abstract in English:

Karam F.S.C., Soares M.P., Haraguchi M., Riet-Correa F., Méndez M.C. & Jarenkow J.A. 2004. [Epidemiological aspects of seneciosis in southern Rio Grande do Sul, Brazil.] Aspectos epidemiológicos da seneciose na região sul do Rio Grande do Sul, Brasil. Pesquisa Veterinária Brasileira 24(4):191-198. Laboratório de Toxicologia, Faculdade de Medicina Veterinária, URCAMP, Bagé, RS 96400-110, Brazil. E-mail: fernando@alternet.com.br Seneciosis is the main cause of livestock mortality due to poisonous plants in the State of Rio Grande do Sul, Brazil. This paper presents epidemiological data of 24 outbreaks in cattle and one in horses, diagnosed by the Regional Diagnostic Laboratory at Pelotas University in southern Rio Grande do Sul, from 1998 to 2000. Additionally, data of 54 outbreaks which occurred in 1978-1997 were analyzed. The farms where outbreaks occurred in 1998-2000 were visited to obtain clinical and epidemiological data and to verify the presence of Senecio spp. Eleven outbreaks (45.83%) affected cattle up to 3 years of age, and 13 (54.16%) cattle over 3 years. Nine (37.5%) outbreaks affected females and 15 (62.5%) males. Ten (41.66%) outbreaks occurred in spring, 4 (16.66%) in summer, 5 (20.83%) in autumn, and 5 (20.83%) in winter. Morbidity rate was estimated with 4.92% and case fatality with 95.59%. The predomionating Senecio species were S. brasiliensis on 12 farms (57.14%), S. selloi on 10 (47.61%), S. oxyphyllus on 6 (28.57%), S. heterotrichius on 3 (14.28%), and S. leptolobus on 1 farm (4.76%). The main clinical signs were progressive emaciation, incoordination, diarrhea, tenesmus, rectal prolapse and aggressiveness. The clinical manifestation periods of affected cattle observed during the farm visits, or of cattle sent for post-mortem examination,were 24-96 hours in 4 outbreaks (16.66%), 4-7 days in 7 (29.16%), 1-2 weeks in 4 (16.66%), 2-3 weeks in 2 (8.33%), 1-2 months in 2 (8.33%), and 2-3 months in 1 outbreak (4.16%). In 4 outbreaks (16.66%) the clinical manifestation period was not established. In outbreaks with longer clinical manifestation periods some animals showed photosensitization. The main necropsy findings were a hard and enlarged liver, distended gall bladder, edema of the mesenterium and abomasum, and increased amount of liquid in the cavities. Histopathological findings were fibroplasia, megalocytosis and biliary ductal proliferation of the liver, and spongy degeneration of the cerebral white matter. Samples of different Senecio species, in different seasons, were analyzed for detection of pyrrolizidine alkaloids (PAs) by thin layer chromatography. Retrorsine was found in Senecio brasiliensis, S. heterotrichius, S. selloi and S. oxyphyllus. In S. brasiliensis and S. heterotrichius one and two more non-identified PAs were detected, respectively. The total PAs concentration by spectrophotometric method was 0.25% for S. brasiliensis, 0.19% for S. heterotrichius, 0.03% for S. oxyphyllus, and 0.03% for S. selloi. The highest PAs concentration occurred in winter (June/July). No alkaloids were found in samples of S. leptolobus. These results show that S. brasiliensis is the most important cause of seneciosis in southern Rio Grande do Sul. Additional data obtained dealt with 54 outbreaks of PAs poisoning in 1978-1997. During this period, 7 outbreaks (12.96%) affected cattle up to 3 years of age, 39 (72.22%) cattle over 3 years, and 3 outbreaks (5.55%) affected cattle of different ages. In 5 outbreaks (9.25%) the age was not informed. Seven outbreaks (12.96%) affected males, 39 (72.22%) females, 3 (5.55%) both sexes, and in 5 outbreaks (9.25%) the sex was not informed. Twenty-three outbreaks (42.59%) occurred in spring, 9 (16.66%) in summer, 9 (16.66%) in autumn, and 13 (24.07%) in winter. The greater number of outbreaks during 1998-2000 (24 outbreaks in 3 years) in regard to 1978-1997 (54 outbreaks in 20 years) is probably due to a decrease of more than 50% in the number of sheep in the region.

• Seneciosis epidemiology poisonous plants Senecio spp Asteraceae pyrrolizidine alkaloids cattle.

Abstract in Portuguese:

Karam F.S.C., Soares M.P., Haraguchi M., Riet-Correa F., Méndez M.C. & Jarenkow J.A. 2004. [Epidemiological aspects of seneciosis in southern Rio Grande do Sul, Brazil.] Aspectos epidemiológicos da seneciose na região sul do Rio Grande do Sul, Brasil. Pesquisa Veterinária Brasileira 24(4):191-198. Laboratório de Toxicologia, Faculdade de Medicina Veterinária, URCAMP, Bagé, RS 96400-110, Brazil. E-mail: fernando@alternet.com.br Seneciosis is the main cause of livestock mortality due to poisonous plants in the State of Rio Grande do Sul, Brazil. This paper presents epidemiological data of 24 outbreaks in cattle and one in horses, diagnosed by the Regional Diagnostic Laboratory at Pelotas University in southern Rio Grande do Sul, from 1998 to 2000. Additionally, data of 54 outbreaks which occurred in 1978-1997 were analyzed. The farms where outbreaks occurred in 1998-2000 were visited to obtain clinical and epidemiological data and to verify the presence of Senecio spp. Eleven outbreaks (45.83%) affected cattle up to 3 years of age, and 13 (54.16%) cattle over 3 years. Nine (37.5%) outbreaks affected females and 15 (62.5%) males. Ten (41.66%) outbreaks occurred in spring, 4 (16.66%) in summer, 5 (20.83%) in autumn, and 5 (20.83%) in winter. Morbidity rate was estimated with 4.92% and case fatality with 95.59%. The predomionating Senecio species were S. brasiliensis on 12 farms (57.14%), S. selloi on 10 (47.61%), S. oxyphyllus on 6 (28.57%), S. heterotrichius on 3 (14.28%), and S. leptolobus on 1 farm (4.76%). The main clinical signs were progressive emaciation, incoordination, diarrhea, tenesmus, rectal prolapse and aggressiveness. The clinical manifestation periods of affected cattle observed during the farm visits, or of cattle sent for post-mortem examination,were 24-96 hours in 4 outbreaks (16.66%), 4-7 days in 7 (29.16%), 1-2 weeks in 4 (16.66%), 2-3 weeks in 2 (8.33%), 1-2 months in 2 (8.33%), and 2-3 months in 1 outbreak (4.16%). In 4 outbreaks (16.66%) the clinical manifestation period was not established. In outbreaks with longer clinical manifestation periods some animals showed photosensitization. The main necropsy findings were a hard and enlarged liver, distended gall bladder, edema of the mesenterium and abomasum, and increased amount of liquid in the cavities. Histopathological findings were fibroplasia, megalocytosis and biliary ductal proliferation of the liver, and spongy degeneration of the cerebral white matter. Samples of different Senecio species, in different seasons, were analyzed for detection of pyrrolizidine alkaloids (PAs) by thin layer chromatography. Retrorsine was found in Senecio brasiliensis, S. heterotrichius, S. selloi and S. oxyphyllus. In S. brasiliensis and S. heterotrichius one and two more non-identified PAs were detected, respectively. The total PAs concentration by spectrophotometric method was 0.25% for S. brasiliensis, 0.19% for S. heterotrichius, 0.03% for S. oxyphyllus, and 0.03% for S. selloi. The highest PAs concentration occurred in winter (June/July). No alkaloids were found in samples of S. leptolobus. These results show that S. brasiliensis is the most important cause of seneciosis in southern Rio Grande do Sul. Additional data obtained dealt with 54 outbreaks of PAs poisoning in 1978-1997. During this period, 7 outbreaks (12.96%) affected cattle up to 3 years of age, 39 (72.22%) cattle over 3 years, and 3 outbreaks (5.55%) affected cattle of different ages. In 5 outbreaks (9.25%) the age was not informed. Seven outbreaks (12.96%) affected males, 39 (72.22%) females, 3 (5.55%) both sexes, and in 5 outbreaks (9.25%) the sex was not informed. Twenty-three outbreaks (42.59%) occurred in spring, 9 (16.66%) in summer, 9 (16.66%) in autumn, and 13 (24.07%) in winter. The greater number of outbreaks during 1998-2000 (24 outbreaks in 3 years) in regard to 1978-1997 (54 outbreaks in 20 years) is probably due to a decrease of more than 50% in the number of sheep in the region.

Abstract in English:

Silva L.A.F., Fioravanti M.C.S., Trindade B.R., Silva O.C., Eurides D., Cunha P.H.J., Silva M.L. & Moura M.I. 2004.[Foot diseases in dairy cows: association with clinical mastitis, metrites and predisposing factors.] Enfermidades digitais em vacas de aptidão leiteira: associação com mastite clínica, metrites e aspectos epidemiológicos. Pesquisa Veterinária Brasileira 24(4):217-222. Escola de Veterinária, Universidade Federal de Goiás, Cx. Postal 131, Goiânia, GO 74001-970, Brazil. E-mail: lafranco@vet.ufg.br With the objective to investigate a possible association between foot diseases, clinical mastitis and/or metritis and predisposing factors for foot diseases, 5300 dairy cows from 80 intensive and semi-intensive farms were used. In 325 (6.13%) cows only foot disease was diagnosed, in 35 (0.66%) foot disease and clinical mastitis, in 52 (0.98%) foot disease and metritis, in 28 (0.53%) foot disease, clinical mastitis and metritis, in 128 (2.42%) only metritis, in 165 (3.11%) only clinical mastitis, and in 89 (1.68%) cows metritis and clinical mastitis. Rapid changes in the diet, high exposure time of hoof horn to slurry and wet conditions, concrete floors, use of footbaths, low frequency of claw trimming, irregular quarantine, and no attention to health aspects during acquisition of the animals were considered as major risk factors for the occurrence of those diseases. The McNemar test for dependent samples showed significant statistical differences between the occurrence of foot disease, clinical mastitis and metritis, in spite of the poor association between those diseases. It was concluded that there was no expressive relationship between foot diseases, clinical mastitis and metritis in lactent cows.

• Foot diseases mastitis metritis epidemiological factors.

Abstract in Portuguese:

Silva L.A.F., Fioravanti M.C.S., Trindade B.R., Silva O.C., Eurides D., Cunha P.H.J., Silva M.L. & Moura M.I. 2004.[Foot diseases in dairy cows: association with clinical mastitis, metrites and predisposing factors.] Enfermidades digitais em vacas de aptidão leiteira: associação com mastite clínica, metrites e aspectos epidemiológicos. Pesquisa Veterinária Brasileira 24(4):217-222. Escola de Veterinária, Universidade Federal de Goiás, Cx. Postal 131, Goiânia, GO 74001-970, Brazil. E-mail: lafranco@vet.ufg.br With the objective to investigate a possible association between foot diseases, clinical mastitis and/or metritis and predisposing factors for foot diseases, 5300 dairy cows from 80 intensive and semi-intensive farms were used. In 325 (6.13%) cows only foot disease was diagnosed, in 35 (0.66%) foot disease and clinical mastitis, in 52 (0.98%) foot disease and metritis, in 28 (0.53%) foot disease, clinical mastitis and metritis, in 128 (2.42%) only metritis, in 165 (3.11%) only clinical mastitis, and in 89 (1.68%) cows metritis and clinical mastitis. Rapid changes in the diet, high exposure time of hoof horn to slurry and wet conditions, concrete floors, use of footbaths, low frequency of claw trimming, irregular quarantine, and no attention to health aspects during acquisition of the animals were considered as major risk factors for the occurrence of those diseases. The McNemar test for dependent samples showed significant statistical differences between the occurrence of foot disease, clinical mastitis and metritis, in spite of the poor association between those diseases. It was concluded that there was no expressive relationship between foot diseases, clinical mastitis and metritis in lactent cows.

Abstract in English:

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

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

Abstract in Portuguese:

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

Abstract in English:

Portiansky E.L., Quiroga M.A., Machuca M.A. & Perfumo C.J. 2004. Mycoplasma suis in naturally infected pigs: an ultrastructural and morphometric study. Pesquisa Veterinária Brasileira 24(1):1-5. Instituto de Patología, Faculdad de Ciencias Veterinarias, Universidad Nacional de La Plata, Calle 60 y 118, C.C. 296, (1900) La Plata, Buenos Aires, Argentina. E-mail: elporti@fcv.unlp.edu.ar Swine eperythrozoonosis is a haemotrophic disease caused by Eperythrozoon suis, actually called Mycoplasma suis, an extracellular bacterial organism that apparently adheres to pig erythrocyte membrane, inducing its deformation and damage. Since little is known about the ultrastructural and morphometrical aspects of this microorganism, the present work aimed to deal with these issues. The ultrastructural study revealed the presence of structures corresponding to tubules disseminated throughout the soma of M. suis. A variable separation between the microorganism membrane and that of the erythrocyte was also observed. The structural and positional attitude of M. suis could allow speculation about its mechanism of action.

• Eperythrozoonosis Mycoplasma suis ultrastructure morphometry pathogenesis.

Abstract in Portuguese:

Portiansky E.L., Quiroga M.A., Machuca M.A. & Perfumo C.J. 2004. Mycoplasma suis in naturally infected pigs: an ultrastructural and morphometric study. Pesquisa Veterinária Brasileira 24(1):1-5. Instituto de Patología, Faculdad de Ciencias Veterinarias, Universidad Nacional de La Plata, Calle 60 y 118, C.C. 296, (1900) La Plata, Buenos Aires, Argentina. E-mail: elporti@fcv.unlp.edu.ar Swine eperythrozoonosis is a haemotrophic disease caused by Eperythrozoon suis, actually called Mycoplasma suis, an extracellular bacterial organism that apparently adheres to pig erythrocyte membrane, inducing its deformation and damage. Since little is known about the ultrastructural and morphometrical aspects of this microorganism, the present work aimed to deal with these issues. The ultrastructural study revealed the presence of structures corresponding to tubules disseminated throughout the soma of M. suis. A variable separation between the microorganism membrane and that of the erythrocyte was also observed. The structural and positional attitude of M. suis could allow speculation about its mechanism of action.

Abstract in English:

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

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

Abstract in Portuguese:

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